module JWT::SecurityUtils

Collection of security methods

@see: github.com/rails/rails/blob/master/activesupport/lib/active_support/security_utils.rb

Public Instance Methods

asn1_to_raw(signature, public_key) click to toggle source
# File lib/jwt/security_utils.rb, line 23
def asn1_to_raw(signature, public_key)
  byte_size = (public_key.group.degree + 7) / 8
  OpenSSL::ASN1.decode(signature).value.map { |value| value.value.to_s(2).rjust(byte_size, "\x00") }.join
end
raw_to_asn1(signature, private_key) click to toggle source
# File lib/jwt/security_utils.rb, line 28
def raw_to_asn1(signature, private_key)
  byte_size = (private_key.group.degree + 7) / 8
  sig_bytes = signature[0..(byte_size - 1)]
  sig_char = signature[byte_size..-1] || ''
  OpenSSL::ASN1::Sequence.new([sig_bytes, sig_char].map { |int| OpenSSL::ASN1::Integer.new(OpenSSL::BN.new(int, 2)) }).to_der
end
rbnacl_fixup(algorithm, key) click to toggle source
# File lib/jwt/security_utils.rb, line 35
def rbnacl_fixup(algorithm, key)
  algorithm = algorithm.sub('HS', 'SHA').to_sym

  return [] unless defined?(RbNaCl) && RbNaCl::HMAC.constants(false).include?(algorithm)

  authenticator = RbNaCl::HMAC.const_get(algorithm)

  # Fall back to OpenSSL for keys larger than 32 bytes.
  return [] if key.bytesize > authenticator.key_bytes

  [
    authenticator,
    key.bytes.fill(0, key.bytesize...authenticator.key_bytes).pack('C*')
  ]
end
secure_compare(left, right) click to toggle source
# File lib/jwt/security_utils.rb, line 8
def secure_compare(left, right)
  left_bytesize = left.bytesize

  return false unless left_bytesize == right.bytesize

  unpacked_left = left.unpack "C#{left_bytesize}"
  result = 0
  right.each_byte { |byte| result |= byte ^ unpacked_left.shift }
  result.zero?
end
verify_rsa(algorithm, public_key, signing_input, signature) click to toggle source
# File lib/jwt/security_utils.rb, line 19
def verify_rsa(algorithm, public_key, signing_input, signature)
  public_key.verify(OpenSSL::Digest.new(algorithm.sub('RS', 'sha')), signature, signing_input)
end