module ActiveModel module SecurePassword extend ActiveSupport::Concern # BCrypt hash function can handle maximum 72 characters, and if we pass # password of length more than 72 characters it ignores extra characters. # Hence need to put a restriction on password length. MAX_PASSWORD_LENGTH_ALLOWED = 72 class << self attr_accessor :min_cost # :nodoc: end self.min_cost = false module ClassMethods # Adds methods to set and authenticate against a BCrypt password. # This mechanism requires you to have a +password_digest+ attribute. # # The following validations are added automatically: # * Password must be present on creation # * Password length should be less than or equal to 72 characters # * Confirmation of password (using a +password_confirmation+ attribute) # # If password confirmation validation is not needed, simply leave out the # value for +password_confirmation+ (i.e. don't provide a form field for # it). When this attribute has a +nil+ value, the validation will not be # triggered. # # For further customizability, it is possible to supress the default # validations by passing validations: false as an argument. # # Add bcrypt (~> 3.1.7) to Gemfile to use #has_secure_password: # # gem 'bcrypt', '~> 3.1.7' # # Example using Active Record (which automatically includes ActiveModel::SecurePassword): # # # Schema: User(name:string, password_digest:string) # class User < ActiveRecord::Base # has_secure_password # end # # user = User.new(name: 'david', password: '', password_confirmation: 'nomatch') # user.save # => false, password required # user.password = 'mUc3m00RsqyRe' # user.save # => false, confirmation doesn't match # user.password_confirmation = 'mUc3m00RsqyRe' # user.save # => true # user.authenticate('notright') # => false # user.authenticate('mUc3m00RsqyRe') # => user # User.find_by(name: 'david').try(:authenticate, 'notright') # => false # User.find_by(name: 'david').try(:authenticate, 'mUc3m00RsqyRe') # => user def has_secure_password(options = {}) # Load bcrypt gem only when has_secure_password is used. # This is to avoid ActiveModel (and by extension the entire framework) # being dependent on a binary library. begin require 'bcrypt' rescue LoadError $stderr.puts "You don't have bcrypt installed in your application. Please add it to your Gemfile and run bundle install" raise end include InstanceMethodsOnActivation if options.fetch(:validations, true) include ActiveModel::Validations # This ensures the model has a password by checking whether the password_digest # is present, so that this works with both new and existing records. However, # when there is an error, the message is added to the password attribute instead # so that the error message will make sense to the end-user. validate do |record| record.errors.add(:password, :blank) unless record.password_digest.present? end validates_length_of :password, maximum: ActiveModel::SecurePassword::MAX_PASSWORD_LENGTH_ALLOWED validates_confirmation_of :password, if: ->{ password.present? } end # This code is necessary as long as the protected_attributes gem is supported. if respond_to?(:attributes_protected_by_default) def self.attributes_protected_by_default #:nodoc: super + ['password_digest'] end end end end module InstanceMethodsOnActivation # Returns +self+ if the password is correct, otherwise +false+. # # class User < ActiveRecord::Base # has_secure_password validations: false # end # # user = User.new(name: 'david', password: 'mUc3m00RsqyRe') # user.save # user.authenticate('notright') # => false # user.authenticate('mUc3m00RsqyRe') # => user def authenticate(unencrypted_password) BCrypt::Password.new(password_digest) == unencrypted_password && self end attr_reader :password # Encrypts the password into the +password_digest+ attribute, only if the # new password is not empty. # # class User < ActiveRecord::Base # has_secure_password validations: false # end # # user = User.new # user.password = nil # user.password_digest # => nil # user.password = 'mUc3m00RsqyRe' # user.password_digest # => "$2a$10$4LEA7r4YmNHtvlAvHhsYAeZmk/xeUVtMTYqwIvYY76EW5GUqDiP4." def password=(unencrypted_password) if unencrypted_password.nil? self.password_digest = nil elsif !unencrypted_password.empty? @password = unencrypted_password cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST : BCrypt::Engine.cost self.password_digest = BCrypt::Password.create(unencrypted_password, cost: cost) end end def password_confirmation=(unencrypted_password) @password_confirmation = unencrypted_password end end end end