<PackageReference Include="BouncyCastle.Cryptography" Version="2.7.0-beta.98" />

TlsECDHanonKeyExchange

(D)TLS ECDH_anon key exchange (see RFC 4492).
using Org.BouncyCastle.Tls.Crypto; using System; using System.IO; namespace Org.BouncyCastle.Tls { public class TlsECDHanonKeyExchange : AbstractTlsKeyExchange { protected TlsECConfig m_ecConfig; protected TlsAgreement m_agreement; public override bool RequiresServerKeyExchange => true; private static int CheckKeyExchange(int keyExchange) { if (keyExchange == 20) return keyExchange; throw new ArgumentException("unsupported key exchange algorithm", "keyExchange"); } public TlsECDHanonKeyExchange(int keyExchange) : this(keyExchange, null) { } public TlsECDHanonKeyExchange(int keyExchange, TlsECConfig ecConfig) : base(CheckKeyExchange(keyExchange)) { m_ecConfig = ecConfig; } public override void SkipServerCredentials() { } public override void ProcessServerCredentials(TlsCredentials serverCredentials) { throw new TlsFatalAlert(80); } public override void ProcessServerCertificate(Certificate serverCertificate) { throw new TlsFatalAlert(10); } public override byte[] GenerateServerKeyExchange() { MemoryStream memoryStream = new MemoryStream(); TlsEccUtilities.WriteECConfig(m_ecConfig, memoryStream); m_agreement = m_context.Crypto.CreateECDomain(m_ecConfig).CreateECDH(); GenerateEphemeral(memoryStream); return memoryStream.ToArray(); } public override void ProcessServerKeyExchange(Stream input) { m_ecConfig = TlsEccUtilities.ReceiveECDHConfig(m_context, input); byte[] point = TlsUtilities.ReadOpaque8(input, 1); m_agreement = m_context.Crypto.CreateECDomain(m_ecConfig).CreateECDH(); ProcessEphemeral(point); } public override short[] GetClientCertificateTypes() { return null; } public override void ProcessClientCredentials(TlsCredentials clientCredentials) { throw new TlsFatalAlert(80); } public override void GenerateClientKeyExchange(Stream output) { GenerateEphemeral(output); } public override void ProcessClientCertificate(Certificate clientCertificate) { throw new TlsFatalAlert(10); } public override void ProcessClientKeyExchange(Stream input) { ProcessEphemeral(TlsUtilities.ReadOpaque8(input, 1)); } public override TlsSecret GeneratePreMasterSecret() { return m_agreement.CalculateSecret(); } protected virtual void GenerateEphemeral(Stream output) { TlsUtilities.WriteOpaque8(m_agreement.GenerateEphemeral(), output); } protected virtual void ProcessEphemeral(byte[] point) { TlsEccUtilities.CheckPointEncoding(m_ecConfig.NamedGroup, point); m_agreement.ReceivePeerValue(point); } } }