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Diffstat (limited to 'activemodel/lib/active_model/secure_password.rb')
| -rw-r--r-- | activemodel/lib/active_model/secure_password.rb | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/activemodel/lib/active_model/secure_password.rb b/activemodel/lib/active_model/secure_password.rb new file mode 100644 index 0000000000..f6ad35769f --- /dev/null +++ b/activemodel/lib/active_model/secure_password.rb @@ -0,0 +1,134 @@ +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 <tt>validations: false</tt> 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 |