Method: SymmetricEncryption.select_cipher

Defined in:
lib/symmetric_encryption/symmetric_encryption.rb

.select_cipher(&block) ⇒ Object

When no header is present in the encrypted data, this custom Block/Proc is used to determine which cipher to use to decrypt the data.

The Block must return a valid cipher

Parameters

encoded_str
  The original encoded string

decoded_str
  The string after being decoded using the global encoding

NOTE: Do not attempt to use a secondary cipher if the previous fails

to decrypt due to an OpenSSL::Cipher::CipherError exception.
This is because in a very small, yet significant number of cases it is
possible to decrypt data using the incorrect key.
Clearly the data returned is garbage, but it still successfully
returns a string of data

Example:

SymmetricEncryption.select_cipher do |encoded_str, decoded_str|
  # Use cipher version 0 if the encoded string ends with "\n" otherwise
  # use the current default cipher
  encoded_str.end_with?("\n") ? SymmetricEncryption.cipher(0) : SymmetricEncryption.cipher
end



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# File 'lib/symmetric_encryption/symmetric_encryption.rb', line 281

def self.select_cipher(&block)
  @select_cipher = block || nil
end