Class: Keen::AESHelper

Inherits:
Object
  • Object
show all
Defined in:
lib/keen/aes_helper.rb

Class Method Summary collapse

Class Method Details

.aes256_decrypt(key, iv_plus_encrypted) ⇒ Object 



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# File 'lib/keen/aes_helper.rb', line 9

def aes256_decrypt(key, iv_plus_encrypted)
  aes = OpenSSL::Cipher::AES.new(256, :CBC)
  iv = iv_plus_encrypted[0, aes.key_len]
  encrypted = iv_plus_encrypted[aes.key_len, iv_plus_encrypted.length]
  aes.decrypt
  aes.key = unhexlify(key)
  aes.iv = unhexlify(iv)
  aes.update(unhexlify(encrypted)) + aes.final
end

.aes256_encrypt(key, plaintext, iv = nil) ⇒ Object

Raises:

  • (OpenSSL::Cipher::CipherError) 


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# File 'lib/keen/aes_helper.rb', line 19

def aes256_encrypt(key, plaintext, iv = nil)
  raise OpenSSL::Cipher::CipherError.new("iv must be 16 bytes") if !iv.nil? && iv.length != 16
  aes = OpenSSL::Cipher::AES.new(256, :CBC)
  aes.encrypt
  aes.key = unhexlify(key)
  aes.iv = iv unless iv.nil?
  iv ||= aes.random_iv
  hexlify(iv) + hexlify(aes.update(plaintext) + aes.final)
end

.hexlify(msg) ⇒ Object 



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# File 'lib/keen/aes_helper.rb', line 29

def hexlify(msg)
  msg.unpack('H*')[0]
end

.unhexlify(msg) ⇒ Object 



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# File 'lib/keen/aes_helper.rb', line 33

def unhexlify(msg)
  [msg].pack('H*')
end