Class: ActiveSupport::MessageEncryptor

Inherits:
Object
  • Object
show all
Defined in:
activesupport/lib/active_support/message_encryptor.rb

Overview

MessageEncryptor is a simple way to encrypt values which get stored somewhere you don’t trust.

The cipher text and initialization vector are base64 encoded and returned to you.

This can be used in situations similar to the MessageVerifier, but where you don’t want users to be able to determine the value of the payload.

Defined Under Namespace

Modules: NullSerializer Classes: InvalidMessage

Constant Summary collapse

OpenSSLCipherError = 
OpenSSL::Cipher.const_defined?(:CipherError) ? OpenSSL::Cipher::CipherError : OpenSSL::CipherError

Instance Method Summary collapse

Constructor Details

#initialize(secret, options = {}) ⇒ MessageEncryptor

Returns a new instance of MessageEncryptor.

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# File 'activesupport/lib/active_support/message_encryptor.rb', line 26

def initialize(secret, options = {})
  unless options.is_a?(Hash)
    ActiveSupport::Deprecation.warn "The second parameter should be an options hash. Use :cipher => 'algorithm' to specify the cipher algorithm."
    options = { :cipher => options }
  end

  @secret = secret
  @cipher = options[:cipher] || 'aes-256-cbc'
  @verifier = MessageVerifier.new(@secret, :serializer => NullSerializer)
  @serializer = options[:serializer] || Marshal
end

Instance Method Details

#decrypt(value) ⇒ Object

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# File 'activesupport/lib/active_support/message_encryptor.rb', line 44

def decrypt(value)
  ActiveSupport::Deprecation.warn "MessageEncryptor#decrypt is deprecated as it is not safe without a signature. " \
    "Please use MessageEncryptor#decrypt_and_verify instead."
  _decrypt(value)
end

#decrypt_and_verify(value) ⇒ Object

Decrypt and verify a message. We need to verify the message in order to avoid padding attacks. Reference: www.limited-entropy.com/padding-oracle-attacks

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# File 'activesupport/lib/active_support/message_encryptor.rb', line 58

def decrypt_and_verify(value)
  _decrypt(verifier.verify(value))
end

#encrypt(value) ⇒ Object

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# File 'activesupport/lib/active_support/message_encryptor.rb', line 38

def encrypt(value)
  ActiveSupport::Deprecation.warn "MessageEncryptor#encrypt is deprecated as it is not safe without a signature. " \
    "Please use MessageEncryptor#encrypt_and_sign instead."
  _encrypt(value)
end

#encrypt_and_sign(value) ⇒ Object

Encrypt and sign a message. We need to sign the message in order to avoid padding attacks. Reference: www.limited-entropy.com/padding-oracle-attacks

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# File 'activesupport/lib/active_support/message_encryptor.rb', line 52

def encrypt_and_sign(value)
  verifier.generate(_encrypt(value))
end