Class: Tem::Keys::Symmetric

Inherits:
Tem::Key show all
Defined in:
lib/tem/keys/symmetric.rb

Overview

Wraps a TEM symmetric key, e.g. an AES key.

Constant Summary collapse

@@cipher_mode = 
'ECB'

Instance Attribute Summary

Attributes inherited from Tem::Key

#ssl_key

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Tem::Key

new_from_ssl_key, #to_tem_key

Constructor Details

#initialize(ssl_key) ⇒ Symmetric

Creates a new symmetric key based on an OpenSSL Cipher instance, augmented with a key accessor.



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# File 'lib/tem/keys/symmetric.rb', line 17

def initialize(ssl_key)
  super ssl_key
  @key = ssl_key.key
  @cipher_class = ssl_key.class
end

Class Method Details

.generate ⇒ Object

Generates a new symmetric key.



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# File 'lib/tem/keys/symmetric.rb', line 9

def self.generate
  cipher = OpenSSL::Cipher::AES128.new @@cipher_mode
  key = cipher.random_key
  self.new key
end

Instance Method Details

#decrypt(data) ⇒ Object 



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# File 'lib/tem/keys/symmetric.rb', line 36

def decrypt(data)
  cipher.encrypt_or_decrypt data, false
end

#encrypt(data) ⇒ Object 



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# File 'lib/tem/keys/symmetric.rb', line 32

def encrypt(data)
  cipher.encrypt_or_decrypt data, true
end

#encrypt_or_decrypt(data, do_encrypt) ⇒ Object 



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# File 'lib/tem/keys/symmetric.rb', line 24

def encrypt_or_decrypt(data, do_encrypt)
  cipher = @cipher_class.new @@cipher_mode
  do_encrypt ? cipher.encrypt : cipher.decrypt
  cipher.key = @key
  cipher.iv = "\0" * 16
  
end

#sign(data) ⇒ Object 



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# File 'lib/tem/keys/symmetric.rb', line 40

def sign(data)
end

#verify(data) ⇒ Object 



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# File 'lib/tem/keys/symmetric.rb', line 43

def verify(data)
end