Class: JWA::Algorithms::KeyManagement::EcdhEs

Inherits:
Object
  • Object
show all
Defined in:
lib/jwa/algorithms/key_management/ecdh_es.rb

Instance Method Summary collapse

Constructor Details

#initialize(ephemeral_key, enc_algorithm, apu, apv) ⇒ EcdhEs

Returns a new instance of EcdhEs.



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# File 'lib/jwa/algorithms/key_management/ecdh_es.rb', line 11

def initialize(ephemeral_key, enc_algorithm, apu, apv)
  @ephemeral_key = ephemeral_key
  @key_length = enc_algorithm.key_length * 8

  algorithm_id = length_encode(enc_algorithm.enc_name)
  apu = length_encode(apu)
  apv = length_encode(apv)
  supp_pub_info = [@key_length].pack('N')
  supp_priv_info = ''

  @info = algorithm_id + apu + apv + supp_pub_info + supp_priv_info
end

Instance Method Details

#decrypt(public_key) ⇒ Object 



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# File 'lib/jwa/algorithms/key_management/ecdh_es.rb', line 33

def decrypt(public_key)
  encrypt(public_key)
end

#encrypt(public_key) ⇒ Object

This is technically not an encryption, but to keep the same interface with other classes, let’s name it this way.



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# File 'lib/jwa/algorithms/key_management/ecdh_es.rb', line 26

def encrypt(public_key)
  z = @ephemeral_key.dh_compute_key(public_key)

  concat_kdf = Support::ConcatKDF.new(Digest::SHA256.new)
  concat_kdf.run(z, @info, @key_length)
end