Class: ElGamal::PrivateKey

Inherits:
Object
  • Object
show all
Defined in:
lib/elgamal/private_key.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(private_a: nil, public_p: nil) ⇒ PrivateKey 



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# File 'lib/elgamal/private_key.rb', line 7

def initialize(private_a: nil, public_p: nil)
  @private_a = private_a
  @public_p = public_p
end

Instance Attribute Details

#private_a ⇒ Object (readonly)

Returns the value of attribute private_a.



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# File 'lib/elgamal/private_key.rb', line 5

def private_a
  @private_a
end

Instance Method Details

#decrypt(ciphertext) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/elgamal/private_key.rb', line 12

def decrypt(ciphertext)
  raise ArgumentError unless ciphertext.instance_of? Ciphertext
  ciphertext[1] * (ciphertext[0].to_bn.mod_exp(@private_a, @public_p)).mod_inverse(@public_p) % @public_p 
end