diff options
Diffstat (limited to 'activesupport/lib/active_support/message_encryptor.rb')
| -rw-r--r-- | activesupport/lib/active_support/message_encryptor.rb | 43 |
1 files changed, 38 insertions, 5 deletions
diff --git a/activesupport/lib/active_support/message_encryptor.rb b/activesupport/lib/active_support/message_encryptor.rb index d5db2920b9..090d51933a 100644 --- a/activesupport/lib/active_support/message_encryptor.rb +++ b/activesupport/lib/active_support/message_encryptor.rb @@ -4,6 +4,7 @@ require "openssl" require "base64" require_relative "core_ext/array/extract_options" require_relative "message_verifier" +require_relative "messages/metadata" module ActiveSupport # MessageEncryptor is a simple way to encrypt values which get stored @@ -21,6 +22,38 @@ module ActiveSupport # crypt = ActiveSupport::MessageEncryptor.new(key) # => #<ActiveSupport::MessageEncryptor ...> # encrypted_data = crypt.encrypt_and_sign('my secret data') # => "NlFBTTMwOUV5UlA1QlNEN2xkY2d6eThYWWh..." # crypt.decrypt_and_verify(encrypted_data) # => "my secret data" + # + # === Confining messages to a specific purpose + # + # By default any message can be used throughout your app. But they can also be + # confined to a specific +:purpose+. + # + # token = crypt.encrypt_and_sign("this is the chair", purpose: :login) + # + # Then that same purpose must be passed when verifying to get the data back out: + # + # crypt.decrypt_and_verify(token, purpose: :login) # => "this is the chair" + # crypt.decrypt_and_verify(token, purpose: :shipping) # => nil + # crypt.decrypt_and_verify(token) # => nil + # + # Likewise, if a message has no purpose it won't be returned when verifying with + # a specific purpose. + # + # token = crypt.encrypt_and_sign("the conversation is lively") + # crypt.decrypt_and_verify(token, purpose: :scare_tactics) # => nil + # crypt.decrypt_and_verify(token) # => "the conversation is lively" + # + # === Making messages expire + # + # By default messages last forever and verifying one year from now will still + # return the original value. But messages can be set to expire at a given + # time with +:expires_in+ or +:expires_at+. + # + # crypt.encrypt_and_sign(parcel, expires_in: 1.month) + # crypt.encrypt_and_sign(doowad, expires_at: Time.now.end_of_year) + # + # Then the messages can be verified and returned upto the expire time. + # Thereafter, verifying returns +nil+. class MessageEncryptor class << self attr_accessor :use_authenticated_message_encryption #:nodoc: @@ -87,14 +120,15 @@ module ActiveSupport # Encrypt and sign a message. We need to sign the message in order to avoid # padding attacks. Reference: http://www.limited-entropy.com/padding-oracle-attacks. - def encrypt_and_sign(value) - verifier.generate(_encrypt(value)) + def encrypt_and_sign(value, expires_at: nil, expires_in: nil, purpose: nil) + data = Messages::Metadata.wrap(value, expires_at: expires_at, expires_in: expires_in, purpose: purpose) + verifier.generate(_encrypt(data)) end # Decrypt and verify a message. We need to verify the message in order to # avoid padding attacks. Reference: http://www.limited-entropy.com/padding-oracle-attacks. - def decrypt_and_verify(value) - _decrypt(verifier.verify(value)) + def decrypt_and_verify(data, purpose: nil) + Messages::Metadata.verify(_decrypt(verifier.verify(data)), purpose) end # Given a cipher, returns the key length of the cipher to help generate the key of desired size @@ -103,7 +137,6 @@ module ActiveSupport end private - def _encrypt(value) cipher = new_cipher cipher.encrypt |