class TTTLS13::Message::ServerHello

Attributes

cipher_suite[R]
extensions[R]
legacy_compression_method[R]
legacy_session_id_echo[R]
legacy_version[R]
msg_type[R]
random[R]

Public Class Methods

deserialize(binary) click to toggle source

@param binary [String]

@raise [TTTLS13::Error::ErrorAlerts]

@return [TTTLS13::Message::ServerHello] rubocop: disable Metrics/AbcSize rubocop: disable Metrics/CyclomaticComplexity rubocop: disable Metrics/MethodLength rubocop: disable Metrics/PerceivedComplexity

# File lib/tttls1.3/message/server_hello.rb, line 90
def self.deserialize(binary)
  raise Error::ErrorAlerts, :internal_error if binary.nil?
  raise Error::ErrorAlerts, :decode_error if binary.length < 39
  raise Error::ErrorAlerts, :internal_error \
    unless binary[0] == HandshakeType::SERVER_HELLO

  msg_len = Convert.bin2i(binary.slice(1, 3))
  legacy_version = binary.slice(4, 2)
  random = binary.slice(6, 32)
  lsid_len = Convert.bin2i(binary[38])
  legacy_session_id_echo = binary.slice(39, lsid_len)
  i = 39 + lsid_len
  cipher_suite = binary.slice(i, 2)
  i += 2
  legacy_compression_method = binary[i]
  i += 1
  exs_len = Convert.bin2i(binary.slice(i, 2))
  i += 2
  exs_bin = binary.slice(i, exs_len)
  if random == HRR_RANDOM
    msg_type = HandshakeType::HELLO_RETRY_REQUEST
    @hrr = true
  else
    msg_type = HandshakeType::SERVER_HELLO
    @hrr = false
  end
  extensions = Extensions.deserialize(exs_bin, msg_type)
  i += exs_len
  raise Error::ErrorAlerts, :decode_error unless i == msg_len + 4 &&
                                                 i == binary.length

  ServerHello.new(legacy_version: legacy_version,
                  random: random,
                  legacy_session_id_echo: legacy_session_id_echo,
                  cipher_suite: cipher_suite,
                  legacy_compression_method: legacy_compression_method,
                  extensions: extensions)
end
new(legacy_version: ProtocolVersion::TLS_1_2, random: OpenSSL::Random.random_bytes(32), legacy_session_id_echo:, cipher_suite:, legacy_compression_method: "\x00", extensions: Extensions.new) click to toggle source

@param legacy_version [String] @param random [String] @param legacy_session_id_echo [String] @param cipher_suite [TTTLS13::CipherSuite] @param legacy_compression_method [String] @param extensions [TTTLS13::Message::Extensions] rubocop: disable Metrics/ParameterLists

# File lib/tttls1.3/message/server_hello.rb, line 51
def initialize(legacy_version: ProtocolVersion::TLS_1_2,
               random: OpenSSL::Random.random_bytes(32),
               legacy_session_id_echo:,
               cipher_suite:,
               legacy_compression_method: "\x00",
               extensions: Extensions.new)
  @msg_type = HandshakeType::SERVER_HELLO
  @legacy_version = legacy_version
  @random = random
  @legacy_session_id_echo = legacy_session_id_echo
  @cipher_suite = cipher_suite
  @legacy_compression_method = legacy_compression_method
  @extensions = extensions
  @hrr = (random == HRR_RANDOM)
end

Public Instance Methods

appearable_extensions?() click to toggle source

@return [Boolean]

# File lib/tttls1.3/message/server_hello.rb, line 139
def appearable_extensions?
  exs = @extensions.keys - APPEARABLE_SH_EXTENSIONS
  exs = @extensions.keys - APPEARABLE_HRR_EXTENSIONS if hrr?
  return true if exs.empty?

  !(exs - DEFINED_EXTENSIONS).empty?
end
downgraded?() click to toggle source

@return [Boolean]

# File lib/tttls1.3/message/server_hello.rb, line 156
def downgraded?
  [DOWNGRADE_PROTECTION_TLS_1_2,
   DOWNGRADE_PROTECTION_TLS_1_1].include?(@random[-8..])
end
hrr?() click to toggle source

@return [Boolean]

# File lib/tttls1.3/message/server_hello.rb, line 134
def hrr?
  @hrr
end
negotiated_tls_1_3?() click to toggle source

@return [Booelan]

# File lib/tttls1.3/message/server_hello.rb, line 148
def negotiated_tls_1_3?
  sv = @extensions[Message::ExtensionType::SUPPORTED_VERSIONS]

  @legacy_version == Message::ProtocolVersion::TLS_1_2 &&
    (sv&.versions || []).first == Message::ProtocolVersion::TLS_1_3
end
serialize() click to toggle source

@return [String]

# File lib/tttls1.3/message/server_hello.rb, line 69
def serialize
  binary = ''
  binary += @legacy_version
  binary += @random
  binary += @legacy_session_id_echo.prefix_uint8_length
  binary += @cipher_suite
  binary += @legacy_compression_method
  binary += @extensions.serialize

  @msg_type + binary.prefix_uint24_length
end