Module: CcipherFactory::KDF

Defined in:
lib/ccipher_factory/kdf/kdf.rb,
lib/ccipher_factory/kdf/hkdf.rb,
lib/ccipher_factory/kdf/pbkdf2.rb,
lib/ccipher_factory/kdf/scrypt.rb

Defined Under Namespace

Modules: HKDF, PBKDF2, Scrypt Classes: KDFEngine, KDFError

Class Method Summary collapse

Class Method Details

.from_encoded(bin, &block) ⇒ Object 



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# File 'lib/ccipher_factory/kdf/kdf.rb', line 34

def self.from_encoded(bin, &block)
  ts = BinStruct.instance.struct_from_bin(bin)
  from_tspec(ts, &block)
end

.from_tspec(ts, &block) ⇒ Object 



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# File 'lib/ccipher_factory/kdf/kdf.rb', line 39

def self.from_tspec(ts, &block)
  case BTag.value_constant(ts.oid)
  when :kdf_scrypt
    kdf = KDFEngine.new
    kdf.extend(Scrypt)
    kdf.cost = ts.cost
    kdf.parallel = ts.parallel
    kdf.blocksize = ts.blocksize
    kdf.salt = ts.salt
    kdf.outByteLength = ts.outByteLength
    kdf.digest = Digest.from_encoded(ts.digest)
    kdf.attachedValue = ts.value
    kdf.derive_init
    kdf
  when :kdf_hkdf
    kdf = KDFEngine.new
    kdf.extend(HKDF)
    kdf.digestAlgo = BTag.value_constant(ts.digest)
    kdf.salt = ts.salt
    kdf.outByteLength = ts.outByteLength
    kdf.attachedValue = ts.value
    kdf.derive_init
  when :kdf_pbkdf2
    kdf = KDFEngine.new
    kdf.extend(PBKDF2)
    kdf.digestAlgo = BTag.value_constant(ts.digest)
    kdf.salt = ts.salt
    kdf.iter = ts.iterations
    kdf.outByteLength = ts.outByteLength
    kdf.attachedValue = ts.value
    kdf.derive_init
  else
    raise KDFError, "Unknown KDF envelope ID '#{ts.oid}'"
  end
end

.instance(eng = :scrypt, &block) ⇒ Object 



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# File 'lib/ccipher_factory/kdf/kdf.rb', line 13

def KDF.instance(eng = :scrypt, &block)
  kdf = KDFEngine.new

  case eng
  when :scrypt
    kdf.extend(Scrypt)
  when :hkdf
    kdf.extend(HKDF)
  when :pbkdf2
    kdf.extend(PBKDF2)
  else
    raise KDFError, "Unknown KDF engine '#{eng}'"
  end

  kdf
end

.supported_kdf_algo ⇒ Object 



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# File 'lib/ccipher_factory/kdf/kdf.rb', line 30

def self.supported_kdf_algo
  [:scrypt, :hkdf, :pbkdf2].freeze
end