Merge branch 'fix/gb/encrypt-runners-tokens-ee' into 'master'

Encrypt runners tokens / EE

See merge request gitlab-org/gitlab-ee!8638

app/models/application_setting.rb

@@ -7,7 +7,7 @@ class ApplicationSetting < ActiveRecord::Base
   include IgnorableColumn
   include ChronicDurationAttribute
 
-  add_authentication_token_field :runners_registration_token
+  add_authentication_token_field :runners_registration_token, encrypted: true, fallback: true
   add_authentication_token_field :health_check_access_token
 
   DOMAIN_LIST_SEPARATOR = %r{\s*[,;]\s*     # comma or semicolon, optionally surrounded by whitespace

app/models/ci/runner.rb

@@ -8,6 +8,10 @@ module Ci
     include RedisCacheable
     include ChronicDurationAttribute
     include FromUnion
+    include TokenAuthenticatable
+
+    add_authentication_token_field :token, encrypted: true, migrating: true
+
     enum access_level: {
       not_protected: 0,
       ref_protected: 1
@@ -38,7 +42,7 @@ module Ci
 
     has_one :last_build, ->() { order('id DESC') }, class_name: 'Ci::Build'
 
-    before_validation :set_default_values
+    before_save :ensure_token
 
     scope :active, -> { where(active: true) }
     scope :paused, -> { where(active: false) }
@@ -144,10 +148,6 @@ module Ci
       end
     end
 
-    def set_default_values
-      self.token = SecureRandom.hex(15) if self.token.blank?
-    end
-
     def assign_to(project, current_user = nil)
       if instance_type?
         self.runner_type = :project_type

app/models/concerns/token_authenticatable.rb

@@ -9,24 +9,18 @@ module TokenAuthenticatable
     private # rubocop:disable Lint/UselessAccessModifier
 
     def add_authentication_token_field(token_field, options = {})
-      @token_fields = [] unless @token_fields
-      unique = options.fetch(:unique, true)
-
-      if @token_fields.include?(token_field)
+      if token_authenticatable_fields.include?(token_field)
         raise ArgumentError.new("#{token_field} already configured via add_authentication_token_field")
       end
 
-      @token_fields << token_field
+      token_authenticatable_fields.push(token_field)
 
       attr_accessor :cleartext_tokens
 
-      strategy = if options[:digest]
-                   TokenAuthenticatableStrategies::Digest.new(self, token_field, options)
-                 else
-                   TokenAuthenticatableStrategies::Insecure.new(self, token_field, options)
-                 end
+      strategy = TokenAuthenticatableStrategies::Base
+        .fabricate(self, token_field, options)
 
-      if unique
+      if options.fetch(:unique, true)
         define_singleton_method("find_by_#{token_field}") do |token|
           strategy.find_token_authenticatable(token)
         end
@@ -54,5 +48,9 @@ module TokenAuthenticatable
         strategy.reset_token!(self)
       end
     end
+
+    def token_authenticatable_fields
+      @token_authenticatable_fields ||= []
+    end
   end
 end

app/models/concerns/token_authenticatable_strategies/base.rb

@@ -2,6 +2,8 @@
 
 module TokenAuthenticatableStrategies
   class Base
+    attr_reader :klass, :token_field, :options
+
     def initialize(klass, token_field, options)
       @klass = klass
       @token_field = token_field
@@ -22,6 +24,7 @@ module TokenAuthenticatableStrategies
 
     def ensure_token(instance)
       write_new_token(instance) unless token_set?(instance)
+      get_token(instance)
     end
 
     # Returns a token, but only saves when the database is in read & write mode
@@ -36,6 +39,36 @@ module TokenAuthenticatableStrategies
       instance.save! if Gitlab::Database.read_write?
     end
 
+    def fallback?
+      unless options[:fallback].in?([true, false, nil])
+        raise ArgumentError, 'fallback: needs to be a boolean value!'
+      end
+
+      options[:fallback] == true
+    end
+
+    def migrating?
+      unless options[:migrating].in?([true, false, nil])
+        raise ArgumentError, 'migrating: needs to be a boolean value!'
+      end
+
+      options[:migrating] == true
+    end
+
+    def self.fabricate(model, field, options)
+      if options[:digest] && options[:encrypted]
+        raise ArgumentError, 'Incompatible options set!'
+      end
+
+      if options[:digest]
+        TokenAuthenticatableStrategies::Digest.new(model, field, options)
+      elsif options[:encrypted]
+        TokenAuthenticatableStrategies::Encrypted.new(model, field, options)
+      else
+        TokenAuthenticatableStrategies::Insecure.new(model, field, options)
+      end
+    end
+
     protected
 
     def write_new_token(instance)
@@ -65,9 +98,5 @@ module TokenAuthenticatableStrategies
     def token_set?(instance)
       raise NotImplementedError
     end
-
-    def token_field_name
-      @token_field
-    end
   end
 end

app/models/concerns/token_authenticatable_strategies/encrypted.rb

+# frozen_string_literal: true
+
+module TokenAuthenticatableStrategies
+  class Encrypted < Base
+    def initialize(*)
+      super
+
+      if migrating? && fallback?
+        raise ArgumentError, '`fallback` and `migrating` options are not compatible!'
+      end
+    end
+
+    def find_token_authenticatable(token, unscoped = false)
+      return if token.blank?
+
+      if fully_encrypted?
+        return find_by_encrypted_token(token, unscoped)
+      end
+
+      if fallback?
+        find_by_encrypted_token(token, unscoped) ||
+          find_by_plaintext_token(token, unscoped)
+      elsif migrating?
+        find_by_plaintext_token(token, unscoped)
+      else
+        raise ArgumentError, 'Unknown encryption phase!'
+      end
+    end
+
+    def ensure_token(instance)
+      # TODO, tech debt, because some specs are testing migrations, but are still
+      # using factory bot to create resources, it might happen that a database
+      # schema does not have "#{token_name}_encrypted" field yet, however a bunch
+      # of models call `ensure_#{token_name}` in `before_save`.
+      #
+      # In that case we are using insecure strategy, but this should only happen
+      # in tests, because otherwise `encrypted_field` is going to exist.
+      #
+      # Another use case is when we are caching resources / columns, like we do
+      # in case of ApplicationSetting.
+
+      return super if instance.has_attribute?(encrypted_field)
+
+      if fully_encrypted?
+        raise ArgumentError, 'Using encrypted strategy when encrypted field is missing!'
+      else
+        insecure_strategy.ensure_token(instance)
+      end
+    end
+
+    def get_token(instance)
+      return insecure_strategy.get_token(instance) if migrating?
+
+      encrypted_token = instance.read_attribute(encrypted_field)
+      token = Gitlab::CryptoHelper.aes256_gcm_decrypt(encrypted_token)
+
+      token || (insecure_strategy.get_token(instance) if fallback?)
+    end
+
+    def set_token(instance, token)
+      raise ArgumentError unless token.present?
+
+      instance[encrypted_field] = Gitlab::CryptoHelper.aes256_gcm_encrypt(token)
+      instance[token_field] = token if migrating?
+      instance[token_field] = nil if fallback?
+      token
+    end
+
+    def fully_encrypted?
+      !migrating? && !fallback?
+    end
+
+    protected
+
+    def find_by_plaintext_token(token, unscoped)
+      insecure_strategy.find_token_authenticatable(token, unscoped)
+    end
+
+    def find_by_encrypted_token(token, unscoped)
+      encrypted_value = Gitlab::CryptoHelper.aes256_gcm_encrypt(token)
+      relation(unscoped).find_by(encrypted_field => encrypted_value)
+    end
+
+    def insecure_strategy
+      @insecure_strategy ||= TokenAuthenticatableStrategies::Insecure
+        .new(klass, token_field, options)
+    end
+
+    def token_set?(instance)
+      raw_token = instance.read_attribute(encrypted_field)
+
+      unless fully_encrypted?
+        raw_token ||= insecure_strategy.get_token(instance)
+      end
+
+      raw_token.present?
+    end
+
+    def encrypted_field
+      @encrypted_field ||= "#{@token_field}_encrypted"
+    end
+  end
+end

app/models/group.rb

@@ -55,7 +55,7 @@ class Group < Namespace
 
   validates :two_factor_grace_period, presence: true, numericality: { greater_than_or_equal_to: 0 }
 
-  add_authentication_token_field :runners_token
+  add_authentication_token_field :runners_token, encrypted: true, migrating: true
 
   after_create :post_create_hook
   after_destroy :post_destroy_hook

app/models/project.rb

@@ -86,7 +86,7 @@ class Project < ActiveRecord::Base
   default_value_for :snippets_enabled, gitlab_config_features.snippets
   default_value_for :only_allow_merge_if_all_discussions_are_resolved, false
 
-  add_authentication_token_field :runners_token
+  add_authentication_token_field :runners_token, encrypted: true, migrating: true
 
   before_validation :mark_remote_mirrors_for_removal, if: -> { RemoteMirror.table_exists? }
 

changelogs/unreleased/fix-gb-encrypt-runners-tokens.yml

+---
+title: Encrypt runners tokens
+merge_request: 23412
+author:
+type: security

config/settings.rb

@@ -120,6 +120,14 @@ class Settings < Settingslogic
       Gitlab::Application.secrets.db_key_base[0..31]
     end
 
+    def attr_encrypted_db_key_base_32
+      Gitlab::Utils.ensure_utf8_size(attr_encrypted_db_key_base, bytes: 32.bytes)
+    end
+
+    def attr_encrypted_db_key_base_12
+      Gitlab::Utils.ensure_utf8_size(attr_encrypted_db_key_base, bytes: 12.bytes)
+    end
+
     # This should be used for :per_attribute_salt_and_iv mode. There is no
     # need to truncate the key because the encryptor will use the salt to
     # generate a hash of the password:

db/migrate/20181115140140_add_encrypted_runners_token_to_settings.rb

+# frozen_string_literal: true
+
+class AddEncryptedRunnersTokenToSettings < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    add_column :application_settings, :runners_registration_token_encrypted, :string
+  end
+end

db/migrate/20181116141415_add_encrypted_runners_token_to_namespaces.rb

+# frozen_string_literal: true
+
+class AddEncryptedRunnersTokenToNamespaces < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    add_column :namespaces, :runners_token_encrypted, :string
+  end
+end

db/migrate/20181116141504_add_encrypted_runners_token_to_projects.rb

+# frozen_string_literal: true
+
+class AddEncryptedRunnersTokenToProjects < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    add_column :projects, :runners_token_encrypted, :string
+  end
+end

db/migrate/20181120151656_add_token_encrypted_to_ci_runners.rb

+# frozen_string_literal: true
+
+class AddTokenEncryptedToCiRunners < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    add_column :ci_runners, :token_encrypted, :string
+  end
+end

db/post_migrate/20181121111200_schedule_runners_token_encryption.rb

+# frozen_string_literal: true
+
+class ScheduleRunnersTokenEncryption < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+  BATCH_SIZE = 10000
+  RANGE_SIZE = 2000
+  MIGRATION = 'EncryptRunnersTokens'
+
+  MODELS = [
+    ::Gitlab::BackgroundMigration::Models::EncryptColumns::Settings,
+    ::Gitlab::BackgroundMigration::Models::EncryptColumns::Namespace,
+    ::Gitlab::BackgroundMigration::Models::EncryptColumns::Project,
+    ::Gitlab::BackgroundMigration::Models::EncryptColumns::Runner
+  ].freeze
+
+  disable_ddl_transaction!
+
+  def up
+    MODELS.each do |model|
+      model.each_batch(of: BATCH_SIZE) do |relation, index|
+        delay = index * 4.minutes
+
+        relation.each_batch(of: RANGE_SIZE) do |relation|
+          range = relation.pluck('MIN(id)', 'MAX(id)').first
+          args = [model.name.demodulize.downcase, *range]
+
+          BackgroundMigrationWorker.perform_in(delay, MIGRATION, args)
+        end
+      end
+    end
+  end
+
+  def down
+    # no-op
+  end
+end

db/schema.rb

@@ -212,6 +212,7 @@ ActiveRecord::Schema.define(version: 20181126153547) do
     t.integer "diff_max_patch_bytes", default: 102400, null: false
     t.integer "archive_builds_in_seconds"
     t.string "commit_email_hostname"
+    t.string "runners_registration_token_encrypted"
     t.index ["custom_project_templates_group_id"], name: "index_application_settings_on_custom_project_templates_group_id", using: :btree
     t.index ["file_template_project_id"], name: "index_application_settings_on_file_template_project_id", using: :btree
     t.index ["usage_stats_set_by_user_id"], name: "index_application_settings_on_usage_stats_set_by_user_id", using: :btree
@@ -623,6 +624,7 @@ ActiveRecord::Schema.define(version: 20181126153547) do
     t.string "ip_address"
     t.integer "maximum_timeout"
     t.integer "runner_type", limit: 2, null: false
+    t.string "token_encrypted"
     t.index ["contacted_at"], name: "index_ci_runners_on_contacted_at", using: :btree
     t.index ["is_shared"], name: "index_ci_runners_on_is_shared", using: :btree
     t.index ["locked"], name: "index_ci_runners_on_locked", using: :btree
@@ -1798,6 +1800,7 @@ ActiveRecord::Schema.define(version: 20181126153547) do
     t.datetime_with_timezone "trial_ends_on"
     t.integer "file_template_project_id"
     t.string "saml_discovery_token"
+    t.string "runners_token_encrypted"
     t.index ["created_at"], name: "index_namespaces_on_created_at", using: :btree
     t.index ["file_template_project_id"], name: "index_namespaces_on_file_template_project_id", using: :btree
     t.index ["ldap_sync_last_successful_update_at"], name: "index_namespaces_on_ldap_sync_last_successful_update_at", using: :btree
@@ -2268,6 +2271,7 @@ ActiveRecord::Schema.define(version: 20181126153547) do
     t.boolean "packages_enabled"
     t.boolean "merge_requests_author_approval"
     t.bigint "pool_repository_id"
+    t.string "runners_token_encrypted"
     t.index ["ci_id"], name: "index_projects_on_ci_id", using: :btree
     t.index ["created_at"], name: "index_projects_on_created_at", using: :btree
     t.index ["creator_id"], name: "index_projects_on_creator_id", using: :btree

lib/api/runner.rb

@@ -19,7 +19,6 @@ module API
         optional :tag_list, type: Array[String], desc: %q(List of Runner's tags)
         optional :maximum_timeout, type: Integer, desc: 'Maximum timeout set when this Runner will handle the job'
       end
-      # rubocop: disable CodeReuse/ActiveRecord
       post '/' do
         attributes = attributes_for_keys([:description, :active, :locked, :run_untagged, :tag_list, :maximum_timeout])
           .merge(get_runner_details_from_request)
@@ -28,10 +27,10 @@ module API
           if runner_registration_token_valid?
             # Create shared runner. Requires admin access
             attributes.merge(runner_type: :instance_type)
-          elsif project = Project.find_by(runners_token: params[:token])
+          elsif project = Project.find_by_runners_token(params[:token])
             # Create a specific runner for the project
             attributes.merge(runner_type: :project_type, projects: [project])
-          elsif group = Group.find_by(runners_token: params[:token])
+          elsif group = Group.find_by_runners_token(params[:token])
             # Create a specific runner for the group
             attributes.merge(runner_type: :group_type, groups: [group])
           else
@@ -46,7 +45,6 @@ module API
           render_validation_error!(runner)
         end
       end
-      # rubocop: enable CodeReuse/ActiveRecord
 
       desc 'Deletes a registered Runner' do
         http_codes [[204, 'Runner was deleted'], [403, 'Forbidden']]

lib/gitlab/background_migration/encrypt_columns.rb

@@ -5,15 +5,17 @@ module Gitlab
     # EncryptColumn migrates data from an unencrypted column - `foo`, say - to
     # an encrypted column - `encrypted_foo`, say.
     #
+    # To avoid depending on a particular version of the model in app/, add a
+    # model to `lib/gitlab/background_migration/models/encrypt_columns` and use
+    # it in the migration that enqueues the jobs, so code can be shared.
+    #
     # For this background migration to work, the table that is migrated _has_ to
     # have an `id` column as the primary key. Additionally, the encrypted column
     # should be managed by attr_encrypted, and map to an attribute with the same
     # name as the unencrypted column (i.e., the unencrypted column should be
-    # shadowed).
+    # shadowed), unless you want to define specific methods / accessors in the
+    # temporary model in `/models/encrypt_columns/your_model.rb`.
     #
-    # To avoid depending on a particular version of the model in app/, add a
-    # model to `lib/gitlab/background_migration/models/encrypt_columns` and use
-    # it in the migration that enqueues the jobs, so code can be shared.
     class EncryptColumns
       def perform(model, attributes, from, to)
         model = model.constantize if model.is_a?(String)
@@ -36,6 +38,10 @@ module Gitlab
         end
       end
 
+      def clear_migrated_values?
+        true
+      end
+
       private
 
       # Build a hash of { attribute => encrypted column name }
@@ -72,7 +78,10 @@ module Gitlab
 
         if instance.changed?
           instance.save!
-          instance.update_columns(to_clear)
+
+          if clear_migrated_values?
+            instance.update_columns(to_clear)
+          end
         end
       end
 

lib/gitlab/background_migration/encrypt_runners_tokens.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    # EncryptColumn migrates data from an unencrypted column - `foo`, say - to
+    # an encrypted column - `encrypted_foo`, say.
+    #
+    # We only create a subclass here because we want to isolate this migration
+    # (migrating unencrypted runner registration tokens to encrypted columns)
+    # from other `EncryptColumns` migration. This class name is going to be
+    # serialized and stored in Redis and later picked by Sidekiq, so we need to
+    # create a separate class name in order to isolate these migration tasks.
+    #
+    # We can solve this differently, see tech debt issue:
+    #
+    # https://gitlab.com/gitlab-org/gitlab-ce/issues/54328
+    #
+    class EncryptRunnersTokens < EncryptColumns
+      def perform(model, from, to)
+        resource = "::Gitlab::BackgroundMigration::Models::EncryptColumns::#{model.to_s.capitalize}"
+        model = resource.constantize
+        attributes = model.encrypted_attributes.keys
+
+        super(model, attributes, from, to)
+      end
+
+      def clear_migrated_values?
+        false
+      end
+    end
+  end
+end

lib/gitlab/background_migration/models/encrypt_columns/namespace.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    module Models
+      module EncryptColumns
+        # This model is shared between synchronous and background migrations to
+        # encrypt the `runners_token` column in `namespaces` table.
+        #
+        class Namespace < ActiveRecord::Base
+          include ::EachBatch
+
+          self.table_name = 'namespaces'
+          self.inheritance_column = :_type_disabled
+
+          def runners_token=(value)
+            self.runners_token_encrypted =
+              ::Gitlab::CryptoHelper.aes256_gcm_encrypt(value)
+          end
+
+          def self.encrypted_attributes
+            { runners_token: { attribute: :runners_token_encrypted } }
+          end
+        end
+      end
+    end
+  end
+end

lib/gitlab/background_migration/models/encrypt_columns/project.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    module Models
+      module EncryptColumns
+        # This model is shared between synchronous and background migrations to
+        # encrypt the `runners_token` column in `projects` table.
+        #
+        class Project < ActiveRecord::Base
+          include ::EachBatch
+
+          self.table_name = 'projects'
+          self.inheritance_column = :_type_disabled
+
+          def runners_token=(value)
+            self.runners_token_encrypted =
+              ::Gitlab::CryptoHelper.aes256_gcm_encrypt(value)
+          end
+
+          def self.encrypted_attributes
+            { runners_token: { attribute: :runners_token_encrypted } }
+          end
+        end
+      end
+    end
+  end
+end

lib/gitlab/background_migration/models/encrypt_columns/runner.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    module Models
+      module EncryptColumns
+        # This model is shared between synchronous and background migrations to
+        # encrypt the `token` column in `ci_runners` table.
+        #
+        class Runner < ActiveRecord::Base
+          include ::EachBatch
+
+          self.table_name = 'ci_runners'
+          self.inheritance_column = :_type_disabled
+
+          def token=(value)
+            self.token_encrypted =
+              ::Gitlab::CryptoHelper.aes256_gcm_encrypt(value)
+          end
+
+          def self.encrypted_attributes
+            { token: { attribute: :token_encrypted } }
+          end
+        end
+      end
+    end
+  end
+end

lib/gitlab/background_migration/models/encrypt_columns/settings.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    module Models
+      module EncryptColumns
+        # This model is shared between synchronous and background migrations to
+        # encrypt the `runners_token` column in `application_settings` table.
+        #
+        class Settings < ActiveRecord::Base
+          include ::EachBatch
+          include ::CacheableAttributes
+
+          self.table_name = 'application_settings'
+          self.inheritance_column = :_type_disabled
+
+          after_commit do
+            ::ApplicationSetting.expire
+          end
+
+          def runners_registration_token=(value)
+            self.runners_registration_token_encrypted =
+              ::Gitlab::CryptoHelper.aes256_gcm_encrypt(value)
+          end
+
+          def self.encrypted_attributes
+            {
+              runners_registration_token: {
+                attribute: :runners_registration_token_encrypted
+              }
+            }
+          end
+        end
+      end
+    end
+  end
+end

lib/gitlab/background_migration/models/encrypt_columns/web_hook.rb

@@ -15,12 +15,12 @@ module Gitlab
           attr_encrypted :token,
                          mode:      :per_attribute_iv,
                          algorithm: 'aes-256-gcm',
-                         key:       Settings.attr_encrypted_db_key_base_truncated
+                         key:       ::Settings.attr_encrypted_db_key_base_truncated
 
           attr_encrypted :url,
                          mode:      :per_attribute_iv,
                          algorithm: 'aes-256-gcm',
-                         key:       Settings.attr_encrypted_db_key_base_truncated
+                         key:       ::Settings.attr_encrypted_db_key_base_truncated
         end
       end
     end

lib/gitlab/crypto_helper.rb

@@ -6,8 +6,8 @@ module Gitlab
 
     AES256_GCM_OPTIONS = {
       algorithm: 'aes-256-gcm',
-      key: Settings.attr_encrypted_db_key_base_truncated,
-      iv: Settings.attr_encrypted_db_key_base_truncated[0..11]
+      key: Settings.attr_encrypted_db_key_base_32,
+      iv: Settings.attr_encrypted_db_key_base_12
     }.freeze
 
     def sha256(value)
@@ -17,7 +17,7 @@ module Gitlab
 
     def aes256_gcm_encrypt(value)
       encrypted_token = Encryptor.encrypt(AES256_GCM_OPTIONS.merge(value: value))
-      Base64.encode64(encrypted_token)
+      Base64.strict_encode64(encrypted_token)
     end
 
     def aes256_gcm_decrypt(value)

lib/gitlab/import_export/import_export.yml

@@ -103,6 +103,7 @@ excluded_attributes:
     - :import_source
     - :mirror
     - :runners_token
+    - :runners_token_encrypted
     - :repository_storage
     - :repository_read_only
     - :lfs_enabled
@@ -125,6 +126,9 @@ excluded_attributes:
     - :packages_enabled
     - :mirror_last_update_at
     - :mirror_last_successful_update_at
+  namespaces:
+    - :runners_token
+    - :runners_token_encrypted
   project_import_state:
     - :last_error
     - :jid
@@ -168,6 +172,9 @@ excluded_attributes:
     - :encrypted_token_iv
     - :encrypted_url
     - :encrypted_url_iv
+  runners:
+    - :token
+    - :token_encrypted
   services:
     - :template
 

lib/gitlab/import_export/relation_factory.rb

@@ -12,6 +12,7 @@ module Gitlab
                     triggers: 'Ci::Trigger',
                     pipeline_schedules: 'Ci::PipelineSchedule',
                     builds: 'Ci::Build',
+                    runners: 'Ci::Runner',
                     hooks: 'ProjectHook',
                     merge_access_levels: 'ProtectedBranch::MergeAccessLevel',
                     push_access_levels: 'ProtectedBranch::PushAccessLevel',
@@ -35,7 +36,7 @@ module Gitlab
 
       EXISTING_OBJECT_CHECK = %i[milestone milestones label labels project_label project_labels group_label group_labels project_feature].freeze
 
-      TOKEN_RESET_MODELS = %w[Ci::Trigger Ci::Build ProjectHook].freeze
+      TOKEN_RESET_MODELS = %w[Project Namespace Ci::Trigger Ci::Build Ci::Runner ProjectHook].freeze
 
       def self.create(*args)
         new(*args).create

lib/gitlab/utils.rb

@@ -16,6 +16,21 @@ module Gitlab
       str.force_encoding(Encoding::UTF_8)
     end
 
+    def ensure_utf8_size(str, bytes:)
+      raise ArgumentError, 'Empty string provided!' if str.empty?
+      raise ArgumentError, 'Negative string size provided!' if bytes.negative?
+
+      truncated = str.each_char.each_with_object(+'') do |char, object|
+        if object.bytesize + char.bytesize > bytes
+          break object
+        else
+          object.concat(char)
+        end
+      end
+
+      truncated + ('0' * (bytes - truncated.bytesize))
+    end
+
     # Append path to host, making sure there's one single / in between
     def append_path(host, path)
       "#{host.to_s.sub(%r{\/+$}, '')}/#{path.to_s.sub(%r{^\/+}, '')}"

spec/config/settings_spec.rb

@@ -6,4 +6,102 @@ describe Settings do
       expect(described_class.omniauth.enabled).to be true
     end
   end
+
+  describe '.attr_encrypted_db_key_base_truncated' do
+    it 'is a string with maximum 32 bytes size' do
+      expect(described_class.attr_encrypted_db_key_base_truncated.bytesize)
+        .to be <= 32
+    end
+  end
+
+  describe '.attr_encrypted_db_key_base_12' do
+    context 'when db key base secret is less than 12 bytes' do
+      before do
+        allow(described_class)
+          .to receive(:attr_encrypted_db_key_base)
+          .and_return('a' * 10)
+      end
+
+      it 'expands db key base secret to 12 bytes' do
+        expect(described_class.attr_encrypted_db_key_base_12)
+          .to eq(('a' * 10) + ('0' * 2))
+      end
+    end
+
+    context 'when key has multiple multi-byte UTF chars exceeding 12 bytes' do
+      before do
+        allow(described_class)
+          .to receive(:attr_encrypted_db_key_base)
+          .and_return('❤' * 18)
+      end
+
+      it 'does not use more than 32 bytes' do
+        db_key_base = described_class.attr_encrypted_db_key_base_12
+
+        expect(db_key_base).to eq('❤' * 4)
+        expect(db_key_base.bytesize).to eq 12
+      end
+    end
+  end
+
+  describe '.attr_encrypted_db_key_base_32' do
+    context 'when db key base secret is less than 32 bytes' do
+      before do
+        allow(described_class)
+          .to receive(:attr_encrypted_db_key_base)
+          .and_return('a' * 10)
+      end
+
+      it 'expands db key base secret to 32 bytes' do
+        expanded_key_base = ('a' * 10) + ('0' * 22)
+
+        expect(expanded_key_base.bytesize).to eq 32
+        expect(described_class.attr_encrypted_db_key_base_32)
+          .to eq expanded_key_base
+      end
+    end
+
+    context 'when db key base secret is 32 bytes' do
+      before do
+        allow(described_class)
+          .to receive(:attr_encrypted_db_key_base)
+          .and_return('a' * 32)
+      end
+
+      it 'returns original value' do
+        expect(described_class.attr_encrypted_db_key_base_32)
+          .to eq 'a' * 32
+      end
+    end
+
+    context 'when db key base contains multi-byte UTF character' do
+      before do
+        allow(described_class)
+          .to receive(:attr_encrypted_db_key_base)
+          .and_return('❤' * 6)
+      end
+
+      it 'does not use more than 32 bytes' do
+        db_key_base = described_class.attr_encrypted_db_key_base_32
+
+        expect(db_key_base).to eq '❤❤❤❤❤❤' + ('0' * 14)
+        expect(db_key_base.bytesize).to eq 32
+      end
+    end
+
+    context 'when db key base multi-byte UTF chars exceeding 32 bytes' do
+      before do
+        allow(described_class)
+          .to receive(:attr_encrypted_db_key_base)
+          .and_return('❤' * 18)
+      end
+
+      it 'does not use more than 32 bytes' do
+        db_key_base = described_class.attr_encrypted_db_key_base_32
+
+        expect(db_key_base).to eq(('❤' * 10) + ('0' * 2))
+        expect(db_key_base.bytesize).to eq 32
+      end
+    end
+  end
 end

spec/lib/gitlab/background_migration/encrypt_runners_tokens_spec.rb

+require 'spec_helper'
+
+describe Gitlab::BackgroundMigration::EncryptRunnersTokens, :migration, schema: 20181121111200 do
+  let(:settings) { table(:application_settings) }
+  let(:namespaces) { table(:namespaces) }
+  let(:projects) { table(:projects) }
+  let(:runners) { table(:ci_runners) }
+
+  context 'when migrating application settings' do
+    before do
+      settings.create!(id: 1, runners_registration_token: 'plain-text-token1')
+    end
+
+    it 'migrates runners registration tokens' do
+      migrate!(:settings, 1, 1)
+
+      encrypted_token = settings.first.runners_registration_token_encrypted
+      decrypted_token = ::Gitlab::CryptoHelper.aes256_gcm_decrypt(encrypted_token)
+
+      expect(decrypted_token).to eq 'plain-text-token1'
+      expect(settings.first.runners_registration_token).to eq 'plain-text-token1'
+    end
+  end
+
+  context 'when migrating namespaces' do
+    before do
+      namespaces.create!(id: 11, name: 'gitlab', path: 'gitlab-org', runners_token: 'my-token1')
+      namespaces.create!(id: 12, name: 'gitlab', path: 'gitlab-org', runners_token: 'my-token2')
+      namespaces.create!(id: 22, name: 'gitlab', path: 'gitlab-org', runners_token: 'my-token3')
+    end
+
+    it 'migrates runners registration tokens' do
+      migrate!(:namespace, 11, 22)
+
+      expect(namespaces.all.reload).to all(
+        have_attributes(runners_token: be_a(String), runners_token_encrypted: be_a(String))
+      )
+    end
+  end
+
+  context 'when migrating projects' do
+    before do
+      namespaces.create!(id: 11, name: 'gitlab', path: 'gitlab-org')
+      projects.create!(id: 111, namespace_id: 11, name: 'gitlab', path: 'gitlab-ce', runners_token: 'my-token1')
+      projects.create!(id: 114, namespace_id: 11, name: 'gitlab', path: 'gitlab-ce', runners_token: 'my-token2')
+      projects.create!(id: 116, namespace_id: 11, name: 'gitlab', path: 'gitlab-ce', runners_token: 'my-token3')
+    end
+
+    it 'migrates runners registration tokens' do
+      migrate!(:project, 111, 116)
+
+      expect(projects.all.reload).to all(
+        have_attributes(runners_token: be_a(String), runners_token_encrypted: be_a(String))
+      )
+    end
+  end
+
+  context 'when migrating runners' do
+    before do
+      runners.create!(id: 201, runner_type: 1, token: 'plain-text-token1')
+      runners.create!(id: 202, runner_type: 1, token: 'plain-text-token2')
+      runners.create!(id: 203, runner_type: 1, token: 'plain-text-token3')
+    end
+
+    it 'migrates runners communication tokens' do
+      migrate!(:runner, 201, 203)
+
+      expect(runners.all.reload).to all(
+        have_attributes(token: be_a(String), token_encrypted: be_a(String))
+      )
+    end
+  end
+
+  def migrate!(model, from, to)
+    subject.perform(model, from, to)
+  end
+end

spec/lib/gitlab/crypto_helper_spec.rb

+require 'spec_helper'
+
+describe Gitlab::CryptoHelper do
+  describe '.sha256' do
+    it 'generates SHA256 digest Base46 encoded' do
+      digest = described_class.sha256('some-value')
+
+      expect(digest).to match %r{\A[A-Za-z0-9+/=]+\z}
+      expect(digest).to eq digest.strip
+    end
+  end
+
+  describe '.aes256_gcm_encrypt' do
+    it 'is Base64 encoded string without new line character' do
+      encrypted = described_class.aes256_gcm_encrypt('some-value')
+
+      expect(encrypted).to match %r{\A[A-Za-z0-9+/=]+\z}
+      expect(encrypted).not_to include "\n"
+    end
+  end
+
+  describe '.aes256_gcm_decrypt' do
+    let(:encrypted) { described_class.aes256_gcm_encrypt('some-value') }
+
+    it 'correctly decrypts encrypted string' do
+      decrypted = described_class.aes256_gcm_decrypt(encrypted)
+
+      expect(decrypted).to eq 'some-value'
+    end
+
+    it 'decrypts a value when it ends with a new line character' do
+      decrypted = described_class.aes256_gcm_decrypt(encrypted + "\n")
+
+      expect(decrypted).to eq 'some-value'
+    end
+  end
+end

spec/lib/gitlab/utils_spec.rb

@@ -127,4 +127,42 @@ describe Gitlab::Utils do
       end
     end
   end
+
+  describe '.ensure_utf8_size' do
+    context 'string is has less bytes than expected' do
+      it 'backfills string with null characters' do
+        transformed = described_class.ensure_utf8_size('a' * 10, bytes: 32)
+
+        expect(transformed.bytesize).to eq 32
+        expect(transformed).to eq(('a' * 10) + ('0' * 22))
+      end
+    end
+
+    context 'string size is exactly the one that is expected' do
+      it 'returns original value' do
+        transformed = described_class.ensure_utf8_size('a' * 32, bytes: 32)
+
+        expect(transformed).to eq 'a' * 32
+        expect(transformed.bytesize).to eq 32
+      end
+    end
+
+    context 'when string contains a few multi-byte UTF characters' do
+      it 'backfills string with null characters' do
+        transformed = described_class.ensure_utf8_size('❤' * 6, bytes: 32)
+
+        expect(transformed).to eq '❤❤❤❤❤❤' + ('0' * 14)
+        expect(transformed.bytesize).to eq 32
+      end
+    end
+
+    context 'when string has multiple multi-byte UTF chars exceeding 32 bytes' do
+      it 'truncates string to 32 characters and backfills it if needed' do
+        transformed = described_class.ensure_utf8_size('❤' * 18, bytes: 32)
+
+        expect(transformed).to eq(('❤' * 10) + ('0' * 2))
+        expect(transformed.bytesize).to eq 32
+      end
+    end
+  end
 end

spec/migrations/schedule_runners_token_encryption_spec.rb

+require 'spec_helper'
+require Rails.root.join('db', 'post_migrate', '20181121111200_schedule_runners_token_encryption')
+
+describe ScheduleRunnersTokenEncryption, :migration do
+  let(:settings) { table(:application_settings) }
+  let(:namespaces) { table(:namespaces) }
+  let(:projects) { table(:projects) }
+  let(:runners) { table(:ci_runners) }
+
+  before do
+    stub_const("#{described_class.name}::BATCH_SIZE", 1)
+
+    settings.create!(id: 1, runners_registration_token: 'plain-text-token1')
+    namespaces.create!(id: 11, name: 'gitlab', path: 'gitlab-org', runners_token: 'my-token1')
+    namespaces.create!(id: 12, name: 'gitlab', path: 'gitlab-org', runners_token: 'my-token2')
+    projects.create!(id: 111, namespace_id: 11, name: 'gitlab', path: 'gitlab-ce', runners_token: 'my-token1')
+    projects.create!(id: 114, namespace_id: 11, name: 'gitlab', path: 'gitlab-ce', runners_token: 'my-token2')
+    runners.create!(id: 201, runner_type: 1, token: 'plain-text-token1')
+    runners.create!(id: 202, runner_type: 1, token: 'plain-text-token2')
+  end
+
+  it 'schedules runners token encryption migration for multiple resources' do
+    Sidekiq::Testing.fake! do
+      Timecop.freeze do
+        migrate!
+
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(4.minutes, 'settings', 1, 1)
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(4.minutes, 'namespace', 11, 11)
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(8.minutes, 'namespace', 12, 12)
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(4.minutes, 'project', 111, 111)
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(8.minutes, 'project', 114, 114)
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(4.minutes, 'runner', 201, 201)
+        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(8.minutes, 'runner', 202, 202)
+        expect(BackgroundMigrationWorker.jobs.size).to eq 7
+      end
+    end
+  end
+end

spec/models/ci/build_spec.rb

@@ -770,33 +770,15 @@ describe Ci::Build do
     let(:subject) { build.hide_secrets(data) }
 
     context 'hide runners token' do
-      let(:data) { 'new token data'}
+      let(:data) { "new #{project.runners_token} data"}
 
-      before do
-        build.project.update(runners_token: 'token')
-      end
-
-      it { is_expected.to eq('new xxxxx data') }
+      it { is_expected.to match(/^new x+ data$/) }
     end
 
     context 'hide build token' do
-      let(:data) { 'new token data'}
-
-      before do
-        build.update(token: 'token')
-      end
-
-      it { is_expected.to eq('new xxxxx data') }
-    end
-
-    context 'hide build token' do
-      let(:data) { 'new token data'}
-
-      before do
-        build.update(token: 'token')
-      end
+      let(:data) { "new #{build.token} data"}
 
-      it { is_expected.to eq('new xxxxx data') }
+      it { is_expected.to match(/^new x+ data$/) }
     end
   end
 

spec/models/concerns/token_authenticatable_spec.rb

@@ -21,44 +21,59 @@ end
 
 describe ApplicationSetting, 'TokenAuthenticatable' do
   let(:token_field) { :runners_registration_token }
+  let(:settings) { described_class.new }
+
   it_behaves_like 'TokenAuthenticatable'
 
   describe 'generating new token' do
     context 'token is not generated yet' do
       describe 'token field accessor' do
-        subject { described_class.new.send(token_field) }
+        subject { settings.send(token_field) }
+
         it { is_expected.not_to be_blank }
       end
 
-      describe 'ensured token' do
-        subject { described_class.new.send("ensure_#{token_field}") }
+      describe "ensure_runners_registration_token" do
+        subject { settings.send("ensure_#{token_field}") }
 
         it { is_expected.to be_a String }
         it { is_expected.not_to be_blank }
+
+        it 'does not persist token' do
+          expect(settings).not_to be_persisted
+        end
       end
 
-      describe 'ensured! token' do
-        subject { described_class.new.send("ensure_#{token_field}!") }
+      describe 'ensure_runners_registration_token!' do
+        subject { settings.send("ensure_#{token_field}!") }
+
+        it 'persists new token as an encrypted string' do
+          expect(subject).to eq settings.reload.runners_registration_token
+          expect(settings.read_attribute('runners_registration_token_encrypted'))
+            .to eq Gitlab::CryptoHelper.aes256_gcm_encrypt(subject)
+          expect(settings).to be_persisted
+        end
 
-        it 'persists new token' do
-          expect(subject).to eq described_class.current[token_field]
+        it 'does not persist token in a clear text' do
+          expect(subject).not_to eq settings.reload
+            .read_attribute('runners_registration_token_encrypted')
         end
       end
     end
 
     context 'token is generated' do
       before do
-        subject.send("reset_#{token_field}!")
+        settings.send("reset_#{token_field}!")
       end
 
       it 'persists a new token' do
-        expect(subject.send(:read_attribute, token_field)).to be_a String
+        expect(settings.runners_registration_token).to be_a String
       end
     end
   end
 
   describe 'setting new token' do
-    subject { described_class.new.send("set_#{token_field}", '0123456789') }
+    subject { settings.send("set_#{token_field}", '0123456789') }
 
     it { is_expected.to eq '0123456789' }
   end

spec/models/concerns/token_authenticatable_strategies/base_spec.rb

+require 'spec_helper'
+
+describe TokenAuthenticatableStrategies::Base do
+  let(:instance) { double(:instance) }
+  let(:field) { double(:field) }
+
+  describe '.fabricate' do
+    context 'when digest stragegy is specified' do
+      it 'fabricates digest strategy object' do
+        strategy = described_class.fabricate(instance, field, digest: true)
+
+        expect(strategy).to be_a TokenAuthenticatableStrategies::Digest
+      end
+    end
+
+    context 'when encrypted strategy is specified' do
+      it 'fabricates encrypted strategy object' do
+        strategy = described_class.fabricate(instance, field, encrypted: true)
+
+        expect(strategy).to be_a TokenAuthenticatableStrategies::Encrypted
+      end
+    end
+
+    context 'when no strategy is specified' do
+      it 'fabricates insecure strategy object' do
+        strategy = described_class.fabricate(instance, field, something: true)
+
+        expect(strategy).to be_a TokenAuthenticatableStrategies::Insecure
+      end
+    end
+
+    context 'when incompatible options are provided' do
+      it 'raises an error' do
+        expect { described_class.fabricate(instance, field, digest: true, encrypted: true) }
+          .to raise_error ArgumentError
+      end
+    end
+  end
+
+  describe '#fallback?' do
+    context 'when fallback is set' do
+      it 'recognizes fallback setting' do
+        strategy = described_class.new(instance, field, fallback: true)
+
+        expect(strategy.fallback?).to be true
+      end
+    end
+
+    context 'when fallback is not a valid value' do
+      it 'raises an error' do
+        strategy = described_class.new(instance, field, fallback: 'something')
+
+        expect { strategy.fallback? }.to raise_error ArgumentError
+      end
+    end
+
+    context 'when fallback is not set' do
+      it 'raises an error' do
+        strategy = described_class.new(instance, field, {})
+
+        expect(strategy.fallback?).to eq false
+      end
+    end
+  end
+end

spec/models/concerns/token_authenticatable_strategies/encrypted_spec.rb

+require 'spec_helper'
+
+describe TokenAuthenticatableStrategies::Encrypted do
+  let(:model) { double(:model) }
+  let(:instance) { double(:instance) }
+
+  let(:encrypted) do
+    Gitlab::CryptoHelper.aes256_gcm_encrypt('my-value')
+  end
+
+  subject do
+    described_class.new(model, 'some_field', options)
+  end
+
+  describe '.new' do
+    context 'when fallback and migration strategies are set' do
+      let(:options) { { fallback: true, migrating: true } }
+
+      it 'raises an error' do
+        expect { subject }.to raise_error ArgumentError, /not compatible/
+      end
+    end
+  end
+
+  describe '#find_token_authenticatable' do
+    context 'when using fallback strategy' do
+      let(:options) { { fallback: true } }
+
+      it 'finds the encrypted resource by cleartext' do
+        allow(model).to receive(:find_by)
+          .with('some_field_encrypted' => encrypted)
+          .and_return('encrypted resource')
+
+        expect(subject.find_token_authenticatable('my-value'))
+          .to eq 'encrypted resource'
+      end
+
+      it 'uses insecure strategy when encrypted token cannot be found' do
+        allow(subject.send(:insecure_strategy))
+          .to receive(:find_token_authenticatable)
+          .and_return('plaintext resource')
+
+        allow(model).to receive(:find_by)
+          .with('some_field_encrypted' => encrypted)
+          .and_return(nil)
+
+        expect(subject.find_token_authenticatable('my-value'))
+          .to eq 'plaintext resource'
+      end
+    end
+
+    context 'when using migration strategy' do
+      let(:options) { { migrating: true } }
+
+      it 'finds the cleartext resource by cleartext' do
+        allow(model).to receive(:find_by)
+          .with('some_field' => 'my-value')
+          .and_return('cleartext resource')
+
+        expect(subject.find_token_authenticatable('my-value'))
+          .to eq 'cleartext resource'
+      end
+
+      it 'returns nil if resource cannot be found' do
+        allow(model).to receive(:find_by)
+          .with('some_field' => 'my-value')
+          .and_return(nil)
+
+        expect(subject.find_token_authenticatable('my-value'))
+          .to be_nil
+      end
+    end
+  end
+
+  describe '#get_token' do
+    context 'when using fallback strategy' do
+      let(:options) { { fallback: true } }
+
+      it 'returns decrypted token when an encrypted token is present' do
+        allow(instance).to receive(:read_attribute)
+          .with('some_field_encrypted')
+          .and_return(encrypted)
+
+        expect(subject.get_token(instance)).to eq 'my-value'
+      end
+
+      it 'returns the plaintext token when encrypted token is not present' do
+        allow(instance).to receive(:read_attribute)
+          .with('some_field_encrypted')
+          .and_return(nil)
+
+        allow(instance).to receive(:read_attribute)
+          .with('some_field')
+          .and_return('cleartext value')
+
+        expect(subject.get_token(instance)).to eq 'cleartext value'
+      end
+    end
+
+    context 'when using migration strategy' do
+      let(:options) { { migrating: true } }
+
+      it 'returns cleartext token when an encrypted token is present' do
+        allow(instance).to receive(:read_attribute)
+          .with('some_field_encrypted')
+          .and_return(encrypted)
+
+        allow(instance).to receive(:read_attribute)
+          .with('some_field')
+          .and_return('my-cleartext-value')
+
+        expect(subject.get_token(instance)).to eq 'my-cleartext-value'
+      end
+
+      it 'returns the cleartext token when encrypted token is not present' do
+        allow(instance).to receive(:read_attribute)
+          .with('some_field_encrypted')
+          .and_return(nil)
+
+        allow(instance).to receive(:read_attribute)
+          .with('some_field')
+          .and_return('cleartext value')
+
+        expect(subject.get_token(instance)).to eq 'cleartext value'
+      end
+    end
+  end
+
+  describe '#set_token' do
+    context 'when using fallback strategy' do
+      let(:options) { { fallback: true } }
+
+      it 'writes encrypted token and removes plaintext token and returns it' do
+        expect(instance).to receive(:[]=)
+          .with('some_field_encrypted', encrypted)
+        expect(instance).to receive(:[]=)
+          .with('some_field', nil)
+
+        expect(subject.set_token(instance, 'my-value')).to eq 'my-value'
+      end
+    end
+
+    context 'when using migration strategy' do
+      let(:options) { { migrating: true } }
+
+      it 'writes encrypted token and writes plaintext token' do
+        expect(instance).to receive(:[]=)
+          .with('some_field_encrypted', encrypted)
+        expect(instance).to receive(:[]=)
+          .with('some_field', 'my-value')
+
+        expect(subject.set_token(instance, 'my-value')).to eq 'my-value'
+      end
+    end
+  end
+end

spec/support/shared_examples/ci_trace_shared_examples.rb

@@ -180,10 +180,9 @@ shared_examples_for 'common trace features' do
     end
 
     context 'runners token' do
-      let(:token) { 'my_secret_token' }
+      let(:token) { build.project.runners_token }
 
       before do
-        build.project.update(runners_token: token)
         trace.set(token)
       end
 
@@ -193,10 +192,9 @@ shared_examples_for 'common trace features' do
     end
 
     context 'hides build token' do
-      let(:token) { 'my_secret_token' }
+      let(:token) { build.token }
 
       before do
-        build.update(token: token)
         trace.set(token)
       end