<PackageReference Include="BouncyCastle.Cryptography" Version="2.6.1" />

TlsImplUtilities

public abstract class TlsImplUtilities
Useful utility methods.
using Org.BouncyCastle.Utilities; using System; namespace Org.BouncyCastle.Tls.Crypto.Impl { public abstract class TlsImplUtilities { public static bool IsSsl(TlsCryptoParameters cryptoParams) { return cryptoParams.ServerVersion.IsSsl; } public static bool IsTlsV10(ProtocolVersion version) { return ProtocolVersion.TLSv10.IsEqualOrEarlierVersionOf(version.GetEquivalentTlsVersion()); } public static bool IsTlsV10(TlsCryptoParameters cryptoParams) { return IsTlsV10(cryptoParams.ServerVersion); } public static bool IsTlsV11(ProtocolVersion version) { return ProtocolVersion.TLSv11.IsEqualOrEarlierVersionOf(version.GetEquivalentTlsVersion()); } public static bool IsTlsV11(TlsCryptoParameters cryptoParams) { return IsTlsV11(cryptoParams.ServerVersion); } public static bool IsTlsV12(ProtocolVersion version) { return ProtocolVersion.TLSv12.IsEqualOrEarlierVersionOf(version.GetEquivalentTlsVersion()); } public static bool IsTlsV12(TlsCryptoParameters cryptoParams) { return IsTlsV12(cryptoParams.ServerVersion); } public static bool IsTlsV13(ProtocolVersion version) { return ProtocolVersion.TLSv13.IsEqualOrEarlierVersionOf(version.GetEquivalentTlsVersion()); } public static bool IsTlsV13(TlsCryptoParameters cryptoParams) { return IsTlsV13(cryptoParams.ServerVersion); } public static byte[] CalculateKeyBlock(TlsCryptoParameters cryptoParams, int length) { SecurityParameters securityParameters = cryptoParams.SecurityParameters; TlsSecret masterSecret = securityParameters.MasterSecret; int prfAlgorithm = securityParameters.PrfAlgorithm; byte[] seed = Arrays.Concatenate(securityParameters.ServerRandom, securityParameters.ClientRandom); return masterSecret.DeriveUsingPrf(prfAlgorithm, "key expansion", seed, length).Extract(); } public unsafe static void CalculateKeyBlock(TlsCryptoParameters cryptoParams, Span<byte> keyBlock) { SecurityParameters securityParameters = cryptoParams.SecurityParameters; TlsSecret masterSecret = securityParameters.MasterSecret; int prfAlgorithm = securityParameters.PrfAlgorithm; Span<byte> span = securityParameters.ClientRandom; Span<byte> span2 = securityParameters.ServerRandom; int num = span2.Length + span.Length; Span<byte> span3 = new Span<byte>(stackalloc byte[(int)(uint)num], num); span2.CopyTo(span3); num = span2.Length; span.CopyTo(span3.Slice(num, span3.Length - num)); masterSecret.DeriveUsingPrf(prfAlgorithm, "key expansion", span3, keyBlock.Length).ExtractTo(keyBlock); } } }