Change encryption for hashing in the documentation.

Throughout the documentations, we are using 'encrypt' incorrectly.
Encrypt means that someone will eventually decrypt the message,
which is obviously not the case for Devise.

I'm changing the docs to use 'hashing' instead.

However, I left the database field as `encrypted_password` for now.
I'll update the db field in an upcoming PR.

README.md

@@ -17,7 +17,7 @@ Devise is a flexible authentication solution for Rails based on Warden. It:
 
 It's composed of 10 modules:
 
-* [Database Authenticatable](http://rubydoc.info/github/plataformatec/devise/master/Devise/Models/DatabaseAuthenticatable): encrypts and stores a password in the database to validate the authenticity of a user while signing in. The authentication can be done both through POST requests or HTTP Basic Authentication.
+* [Database Authenticatable](http://rubydoc.info/github/plataformatec/devise/master/Devise/Models/DatabaseAuthenticatable): hashes and stores a password in the database to validate the authenticity of a user while signing in. The authentication can be done both through POST requests or HTTP Basic Authentication.
 * [Omniauthable](http://rubydoc.info/github/plataformatec/devise/master/Devise/Models/Omniauthable): adds OmniAuth (https://github.com/intridea/omniauth) support.
 * [Confirmable](http://rubydoc.info/github/plataformatec/devise/master/Devise/Models/Confirmable): sends emails with confirmation instructions and verifies whether an account is already confirmed during sign in.
 * [Recoverable](http://rubydoc.info/github/plataformatec/devise/master/Devise/Models/Recoverable): resets the user password and sends reset instructions.
@@ -174,7 +174,7 @@ member_session
 
 ### Configuring Models
 
-The Devise method in your models also accepts some options to configure its modules. For example, you can choose the cost of the encryption algorithm with:
+The Devise method in your models also accepts some options to configure its modules. For example, you can choose the cost of the hashing algorithm with:
 
 ```ruby
 devise :database_authenticatable, :registerable, :confirmable, :recoverable, stretches: 20

lib/devise.rb

@@ -61,7 +61,7 @@ module Devise
   mattr_accessor :rememberable_options
   @@rememberable_options = {}
 
-  # The number of times to encrypt password.
+  # The number of times to hash the password.
   mattr_accessor :stretches
   @@stretches = 10
 
@@ -146,7 +146,7 @@ module Devise
   mattr_accessor :timeout_in
   @@timeout_in = 30.minutes
 
-  # Used to encrypt password. Please generate one with rake secret.
+  # Used to hash the password. Please generate one with rake secret.
   mattr_accessor :pepper
   @@pepper = nil
 

lib/devise/encryptor.rb

@@ -9,14 +9,14 @@ module Devise
       ::BCrypt::Password.create(password, cost: klass.stretches).to_s
     end
 
-    def self.compare(klass, encrypted_password, password)
-      return false if encrypted_password.blank?
-      bcrypt   = ::BCrypt::Password.new(encrypted_password)
+    def self.compare(klass, hashed_password, password)
+      return false if hashed_password.blank?
+      bcrypt   = ::BCrypt::Password.new(hashed_password)
       if klass.pepper.present?
         password = "#{password}#{klass.pepper}"
       end
       password = ::BCrypt::Engine.hash_secret(password, bcrypt.salt)
-      Devise.secure_compare(password, encrypted_password)
+      Devise.secure_compare(password, hashed_password)
     end
   end
 end

lib/devise/models/database_authenticatable.rb

@@ -7,8 +7,8 @@ module Devise
   end
 
   module Models
-    # Authenticatable Module, responsible for encrypting password and validating
-    # authenticity of a user while signing in.
+    # Authenticatable Module, responsible for hashing the password and
+    # validating the authenticity of a user while signing in.
     #
     # == Options
     #
@@ -37,7 +37,9 @@ module Devise
         [:encrypted_password] + klass.authentication_keys
       end
 
-      # Generates password encryption based on the given value.
+      # Generates a hashed password based on the given value.
+      # For legacy reasons, we use `encrypted_password` to store
+      # the hashed password.
       def password=(new_password)
         attribute_will_change! 'password'
         @password = new_password
@@ -142,11 +144,11 @@ module Devise
 
     protected
 
-      # Digests the password using bcrypt. Custom encryption should override
+      # Hashes the password using bcrypt. Custom hash functions should override
       # this method to apply their own algorithm.
       #
       # See https://github.com/plataformatec/devise-encryptable for examples
-      # of other encryption engines.
+      # of other hashing engines.
       def password_digest(password)
         Devise::Encryptor.digest(self.class, password)
       end

lib/devise/strategies/database_authenticatable.rb

@@ -6,15 +6,15 @@ module Devise
     class DatabaseAuthenticatable < Authenticatable
       def authenticate!
         resource  = password.present? && mapping.to.find_for_database_authentication(authentication_hash)
-        encrypted = false
+        hashed = false
 
-        if validate(resource){ encrypted = true; resource.valid_password?(password) }
+        if validate(resource){ hashed = true; resource.valid_password?(password) }
           remember_me(resource)
           resource.after_database_authentication
           success!(resource)
         end
 
-        mapping.to.new.password = password if !encrypted && Devise.paranoid
+        mapping.to.new.password = password if !hashed && Devise.paranoid
         fail(:not_found_in_database) unless resource
       end
     end

lib/generators/templates/devise.rb

@@ -92,16 +92,16 @@ Devise.setup do |config|
 
   # ==> Configuration for :database_authenticatable
   # For bcrypt, this is the cost for hashing the password and defaults to 10. If
-  # using other encryptors, it sets how many times you want the password re-encrypted.
+  # using other algorithms, it sets how many times you want the password to be hashed.
   #
   # Limiting the stretches to just one in testing will increase the performance of
   # your test suite dramatically. However, it is STRONGLY RECOMMENDED to not use
   # a value less than 10 in other environments. Note that, for bcrypt (the default
-  # encryptor), the cost increases exponentially with the number of stretches (e.g.
+  # algorithm), the cost increases exponentially with the number of stretches (e.g.
   # a value of 20 is already extremely slow: approx. 60 seconds for 1 calculation).
   config.stretches = Rails.env.test? ? 1 : 10
 
-  # Set up a pepper to generate the encrypted password.
+  # Set up a pepper to generate the hashed password.
   # config.pepper = '<%= SecureRandom.hex(64) %>'
 
   # Send a notification email when the user's password is changed
@@ -201,11 +201,11 @@ Devise.setup do |config|
   # config.sign_in_after_reset_password = true
 
   # ==> Configuration for :encryptable
-  # Allow you to use another encryption algorithm besides bcrypt (default). You can use
-  # :sha1, :sha512 or encryptors from others authentication tools as :clearance_sha1,
-  # :authlogic_sha512 (then you should set stretches above to 20 for default behavior)
-  # and :restful_authentication_sha1 (then you should set stretches to 10, and copy
-  # REST_AUTH_SITE_KEY to pepper).
+  # Allow you to use another hashing or encryption algorithm besides bcrypt (default).
+  # You can use :sha1, :sha512 or algorithms from others authentication tools as
+  # :clearance_sha1, :authlogic_sha512 (then you should set stretches above to 20
+  # for default behavior) and :restful_authentication_sha1 (then you should set
+  # stretches to 10, and copy REST_AUTH_SITE_KEY to pepper).
   #
   # Require the `devise-encryptable` gem when using anything other than bcrypt
   # config.encryptor = :sha512

test/models/database_authenticatable_test.rb

@@ -92,28 +92,28 @@ class DatabaseAuthenticatableTest < ActiveSupport::TestCase
     assert user.respond_to?(:password_confirmation)
   end
 
-  test 'should generate encrypted password while setting password' do
+  test 'should generate a hashed password while setting password' do
     user = new_user
     assert_present user.encrypted_password
   end
 
-  test 'should support custom encryption methods' do
-    user = UserWithCustomEncryption.new(password: '654321')
+  test 'should support custom hashing methods' do
+    user = UserWithCustomHashing.new(password: '654321')
     assert_equal user.encrypted_password, '123456'
   end
 
-  test 'allow authenticatable_salt to work even with nil encrypted password' do
+  test 'allow authenticatable_salt to work even with nil hashed password' do
     user = User.new
     user.encrypted_password = nil
     assert_nil user.authenticatable_salt
   end
 
-  test 'should not generate encrypted password if password is blank' do
+  test 'should not generate a hashed password if password is blank' do
     assert_blank new_user(password: nil).encrypted_password
     assert_blank new_user(password: '').encrypted_password
   end
 
-  test 'should encrypt password again if password has changed' do
+  test 'should hash password again if password has changed' do
     user = create_user
     encrypted_password = user.encrypted_password
     user.password = user.password_confirmation = 'new_password'

test/test_models.rb

@@ -12,7 +12,7 @@ class UserWithValidation < User
   validates_presence_of :username
 end
 
-class UserWithCustomEncryption < User
+class UserWithCustomHashing < User
   protected
   def password_digest(password)
     password.reverse