Encrypted cookies

actionpack/lib/action_controller/metal/http_authentication.rb

@@ -249,9 +249,9 @@ def authentication_request(controller, realm, message = nil)
       end
 
       def secret_token(request)
-        secret = request.env["action_dispatch.secret_token"]
-        raise "You must set config.secret_token in your app's config" if secret.blank?
-        secret
+        key_generator  = request.env["action_dispatch.key_generator"]
+        http_auth_salt = request.env["action_dispatch.http_auth_salt"]
+        key_generator.generate_key(http_auth_salt)
       end
 
       # Uses an MD5 digest based on time to generate a value to be used only once.

actionpack/lib/action_controller/metal/request_forgery_protection.rb

@@ -121,11 +121,11 @@ def exists?
 
         class NullCookieJar < ActionDispatch::Cookies::CookieJar #:nodoc:
           def self.build(request)
-            secret = request.env[ActionDispatch::Cookies::TOKEN_KEY]
-            host   = request.host
-            secure = request.ssl?
+            key_generator = request.env[ActionDispatch::Cookies::GENERATOR_KEY]
+            host          = request.host
+            secure        = request.ssl?
 
-            new(secret, host, secure)
+            new(key_generator, host, secure)
           end
 
           def write(*)

actionpack/lib/action_dispatch.rb

@@ -81,10 +81,11 @@ module Http
   end
 
   module Session
-    autoload :AbstractStore, 'action_dispatch/middleware/session/abstract_store'
-    autoload :CookieStore,   'action_dispatch/middleware/session/cookie_store'
-    autoload :MemCacheStore, 'action_dispatch/middleware/session/mem_cache_store'
-    autoload :CacheStore,    'action_dispatch/middleware/session/cache_store'
+    autoload :AbstractStore,        'action_dispatch/middleware/session/abstract_store'
+    autoload :CookieStore,          'action_dispatch/middleware/session/cookie_store'
+    autoload :EncryptedCookieStore, 'action_dispatch/middleware/session/cookie_store'
+    autoload :MemCacheStore,        'action_dispatch/middleware/session/mem_cache_store'
+    autoload :CacheStore,           'action_dispatch/middleware/session/cache_store'
   end
 
   mattr_accessor :test_app

actionpack/lib/action_dispatch/middleware/cookies.rb

@@ -1,5 +1,6 @@
 require 'active_support/core_ext/hash/keys'
 require 'active_support/core_ext/module/attribute_accessors'
+require 'active_support/message_verifier'
 
 module ActionDispatch
   class Request < Rack::Request
@@ -27,7 +28,7 @@ def cookie_jar
   #   cookies[:login] = { value: "XJ-122", expires: 1.hour.from_now }
   #
   #   # Sets a signed cookie, which prevents users from tampering with its value.
-  #   # The cookie is signed by your app's <tt>config.secret_token</tt> value.
+  #   # The cookie is signed by your app's <tt>config.secret_key_base</tt> value.
   #   # It can be read using the signed method <tt>cookies.signed[:key]</tt>
   #   cookies.signed[:user_id] = current_user.id
   #
@@ -79,8 +80,12 @@ def cookie_jar
   # * <tt>:httponly</tt> - Whether this cookie is accessible via scripting or
   #   only HTTP. Defaults to +false+.
   class Cookies
-    HTTP_HEADER = "Set-Cookie".freeze
-    TOKEN_KEY   = "action_dispatch.secret_token".freeze
+    HTTP_HEADER   = "Set-Cookie".freeze
+    GENERATOR_KEY = "action_dispatch.key_generator".freeze
+    SIGNED_COOKIE_SALT = "action_dispatch.signed_cookie_salt".freeze
+    ENCRYPTED_COOKIE_SALT = "action_dispatch.encrypted_cookie_salt".freeze
+    ENCRYPTED_SIGNED_COOKIE_SALT = "action_dispatch.encrypted_signed_cookie_salt".freeze
+
 
     # Raised when storing more than 4K of session data.
     CookieOverflow = Class.new StandardError
@@ -103,21 +108,27 @@ class CookieJar #:nodoc:
       DOMAIN_REGEXP = /[^.]*\.([^.]*|..\...|...\...)$/
 
       def self.build(request)
-        secret = request.env[TOKEN_KEY]
+        env = request.env
+        key_generator = env[GENERATOR_KEY]
+        options = { signed_cookie_salt: env[SIGNED_COOKIE_SALT],
+                    encrypted_cookie_salt: env[ENCRYPTED_COOKIE_SALT],
+                    encrypted_signed_cookie_salt: env[ENCRYPTED_SIGNED_COOKIE_SALT] }
+
         host = request.host
         secure = request.ssl?
 
-        new(secret, host, secure).tap do |hash|
+        new(key_generator, host, secure, options).tap do |hash|
           hash.update(request.cookies)
         end
       end
 
-      def initialize(secret = nil, host = nil, secure = false)
-        @secret = secret
+      def initialize(key_generator, host = nil, secure = false, options = {})
+        @key_generator = key_generator
         @set_cookies = {}
         @delete_cookies = {}
         @host = host
         @secure = secure
+        @options = options
         @cookies = {}
       end
 
@@ -220,15 +231,15 @@ def clear(options = {})
       #   cookies.permanent.signed[:remember_me] = current_user.id
       #   # => Set-Cookie: remember_me=BAhU--848956038e692d7046deab32b7131856ab20e14e; path=/; expires=Sun, 16-Dec-2029 03:24:16 GMT
       def permanent
-        @permanent ||= PermanentCookieJar.new(self, @secret)
+        @permanent ||= PermanentCookieJar.new(self, @key_generator, @options)
       end
 
       # Returns a jar that'll automatically generate a signed representation of cookie value and verify it when reading from
       # the cookie again. This is useful for creating cookies with values that the user is not supposed to change. If a signed
       # cookie was tampered with by the user (or a 3rd party), an ActiveSupport::MessageVerifier::InvalidSignature exception will
       # be raised.
       #
-      # This jar requires that you set a suitable secret for the verification on your app's +config.secret_token+.
+      # This jar requires that you set a suitable secret for the verification on your app's +config.secret_key_base+.
       #
       # Example:
       #
@@ -237,7 +248,23 @@ def permanent
       #
       #   cookies.signed[:discount] # => 45
       def signed
-        @signed ||= SignedCookieJar.new(self, @secret)
+        @signed ||= SignedCookieJar.new(self, @key_generator, @options)
+      end
+
+      # Returns a jar that'll automatically encrypt cookie values before sending them to the client and will decrypt them for read.
+      # If the cookie was tampered with by the user (or a 3rd party), an ActiveSupport::MessageVerifier::InvalidSignature exception
+      # will be raised.
+      #
+      # This jar requires that you set a suitable secret for the verification on your app's +config.secret_key_base+.
+      #
+      # Example:
+      #
+      #   cookies.encrypted[:discount] = 45
+      #   # => Set-Cookie: discount=ZS9ZZ1R4cG1pcUJ1bm80anhQang3dz09LS1mbDZDSU5scGdOT3ltQ2dTdlhSdWpRPT0%3D--ab54663c9f4e3bc340c790d6d2b71e92f5b60315; path=/
+      #
+      #   cookies.encrypted[:discount] # => 45
+      def encrypted
+        @encrypted ||= EncryptedCookieJar.new(self, @key_generator, @options)
       end
 
       def write(headers)
@@ -261,8 +288,10 @@ def write_cookie?(cookie)
     end
 
     class PermanentCookieJar < CookieJar #:nodoc:
-      def initialize(parent_jar, secret)
-        @parent_jar, @secret = parent_jar, secret
+      def initialize(parent_jar, key_generator, options = {})
+        @parent_jar = parent_jar
+        @key_generator = key_generator
+        @options = options
       end
 
       def []=(key, options)
@@ -283,11 +312,11 @@ def method_missing(method, *arguments, &block)
 
     class SignedCookieJar < CookieJar #:nodoc:
       MAX_COOKIE_SIZE = 4096 # Cookies can typically store 4096 bytes.
-      SECRET_MIN_LENGTH = 30 # Characters
 
-      def initialize(parent_jar, secret)
-        ensure_secret_secure(secret)
+      def initialize(parent_jar, key_generator, options = {})
         @parent_jar = parent_jar
+        @options = options
+        secret = key_generator.generate_key(@options[:signed_cookie_salt])
         @verifier   = ActiveSupport::MessageVerifier.new(secret)
       end
 
@@ -314,26 +343,41 @@ def []=(key, options)
       def method_missing(method, *arguments, &block)
         @parent_jar.send(method, *arguments, &block)
       end
+    end
 
-    protected
-
-      # To prevent users from using something insecure like "Password" we make sure that the
-      # secret they've provided is at least 30 characters in length.
-      def ensure_secret_secure(secret)
-        if secret.blank?
-          raise ArgumentError, "A secret is required to generate an " +
-            "integrity hash for cookie session data. Use " +
-            "config.secret_token = \"some secret phrase of at " +
-            "least #{SECRET_MIN_LENGTH} characters\"" +
-            "in config/initializers/secret_token.rb"
+    class EncryptedCookieJar < SignedCookieJar #:nodoc:
+      def initialize(parent_jar, key_generator, options = {})
+        if ActiveSupport::DummyKeyGenerator === key_generator
+          raise "Encrypted Cookies must be used in conjunction with config.secret_key_base." +
+                "Set config.secret_key_base in config/initializers/secret_token.rb"
         end
 
-        if secret.length < SECRET_MIN_LENGTH
-          raise ArgumentError, "Secret should be something secure, " +
-            "like \"#{SecureRandom.hex(16)}\". The value you " +
-            "provided, \"#{secret}\", is shorter than the minimum length " +
-            "of #{SECRET_MIN_LENGTH} characters"
+        @parent_jar = parent_jar
+        @options = options
+        secret = key_generator.generate_key(@options[:encrypted_cookie_salt])
+        sign_secret = key_generator.generate_key(@options[:encrypted_signed_cookie_salt])
+        @encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
+      end
+
+      def [](name)
+        if encrypted_message = @parent_jar[name]
+          @encryptor.decrypt_and_verify(encrypted_message)
         end
+      rescue ActiveSupport::MessageVerifier::InvalidSignature,
+             ActiveSupport::MessageVerifier::InvalidMessage
+        nil
+      end
+
+      def []=(key, options)
+        if options.is_a?(Hash)
+          options.symbolize_keys!
+        else
+          options = { :value => options }
+        end
+        options[:value] = @encryptor.encrypt_and_sign(options[:value])
+
+        raise CookieOverflow if options[:value].size > MAX_COOKIE_SIZE
+        @parent_jar[key] = options
       end
     end
 

actionpack/lib/action_dispatch/middleware/session/cookie_store.rb

@@ -57,8 +57,7 @@ def destroy_session(env, session_id, options)
       def unpacked_cookie_data(env)
         env["action_dispatch.request.unsigned_session_cookie"] ||= begin
           stale_session_check! do
-            request = ActionDispatch::Request.new(env)
-            if data = request.cookie_jar.signed[@key]
+            if data = cookie_jar(env)[@key]
               data.stringify_keys!
             end
             data || {}
@@ -72,8 +71,26 @@ def set_session(env, sid, session_data, options)
       end
 
       def set_cookie(env, session_id, cookie)
+        cookie_jar(env)[@key] = cookie
+      end
+
+      def get_cookie
+        cookie_jar(env)[@key]
+      end
+
+      def cookie_jar(env)
+        request = ActionDispatch::Request.new(env)
+        request.cookie_jar.signed
+      end
+    end
+
+    class EncryptedCookieStore < CookieStore
+
+      private
+
+      def cookie_jar(env)
         request = ActionDispatch::Request.new(env)
-        request.cookie_jar.signed[@key] = cookie
+        request.cookie_jar.encrypted
       end
     end
   end

actionpack/lib/action_dispatch/railtie.rb

@@ -13,6 +13,10 @@ class Railtie < Rails::Railtie
     config.action_dispatch.rescue_responses = { }
     config.action_dispatch.default_charset = nil
     config.action_dispatch.rack_cache = false
+    config.action_dispatch.http_auth_salt = 'http authentication'
+    config.action_dispatch.signed_cookie_salt = 'signed cookie'
+    config.action_dispatch.encrypted_cookie_salt = 'encrypted cookie'
+    config.action_dispatch.encrypted_signed_cookie_salt = 'signed encrypted cookie'
 
     config.action_dispatch.default_headers = {
       'X-Frame-Options' => 'SAMEORIGIN',

actionpack/test/controller/flash_test.rb

@@ -1,4 +1,6 @@
 require 'abstract_unit'
+# FIXME remove DummyKeyGenerator and this require in 4.1
+require 'active_support/key_generator'
 
 class FlashTest < ActionController::TestCase
   class TestController < ActionController::Base
@@ -217,7 +219,7 @@ def test_redirect_to_with_adding_flash_types
 
 class FlashIntegrationTest < ActionDispatch::IntegrationTest
   SessionKey = '_myapp_session'
-  SessionSecret = 'b3c631c314c0bbca50c1b2843150fe33'
+  Generator  =  ActiveSupport::DummyKeyGenerator.new('b3c631c314c0bbca50c1b2843150fe33')
 
   class TestController < ActionController::Base
     add_flash_types :bar
@@ -291,7 +293,7 @@ def test_added_flash_types_method
 
     # Overwrite get to send SessionSecret in env hash
     def get(path, parameters = nil, env = {})
-      env["action_dispatch.secret_token"] ||= SessionSecret
+      env["action_dispatch.key_generator"] ||= Generator
       super
     end
 

actionpack/test/controller/http_digest_authentication_test.rb

@@ -1,4 +1,6 @@
 require 'abstract_unit'
+# FIXME remove DummyKeyGenerator and this require in 4.1
+require 'active_support/key_generator'
 
 class HttpDigestAuthenticationTest < ActionController::TestCase
   class DummyDigestController < ActionController::Base
@@ -40,8 +42,8 @@ def authenticate_with_request
 
   setup do
     # Used as secret in generating nonce to prevent tampering of timestamp
-    @secret = "session_options_secret"
-    @request.env["action_dispatch.secret_token"] = @secret
+    @secret = "4fb45da9e4ab4ddeb7580d6a35503d99"
+    @request.env["action_dispatch.key_generator"] = ActiveSupport::DummyKeyGenerator.new(@secret)
   end
 
   teardown do