SuperVPN/output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Crypto/Tls/TlsProtocol.cs

using System;
using System.Collections;
using System.IO;
using Org.BouncyCastle.Crypto.Prng;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities;

namespace Org.BouncyCastle.Crypto.Tls;

public abstract class TlsProtocol
{
	internal class HandshakeMessage : MemoryStream
	{
		internal HandshakeMessage(byte handshakeType)
			: this(handshakeType, 60)
		{
		}

		internal HandshakeMessage(byte handshakeType, int length)
			: base(length + 4)
		{
			TlsUtilities.WriteUint8(handshakeType, this);
			TlsUtilities.WriteUint24(0, this);
		}

		internal void Write(byte[] data)
		{
			Write(data, 0, data.Length);
		}

		internal void WriteToRecordStream(TlsProtocol protocol)
		{
			long num = Length - 4;
			TlsUtilities.CheckUint24(num);
			Position = 1L;
			TlsUtilities.WriteUint24((int)num, this);
			byte[] buffer = GetBuffer();
			int len = (int)Length;
			protocol.WriteHandshakeMessage(buffer, 0, len);
			Platform.Dispose(this);
		}
	}

	protected const short CS_START = 0;

	protected const short CS_CLIENT_HELLO = 1;

	protected const short CS_SERVER_HELLO = 2;

	protected const short CS_SERVER_SUPPLEMENTAL_DATA = 3;

	protected const short CS_SERVER_CERTIFICATE = 4;

	protected const short CS_CERTIFICATE_STATUS = 5;

	protected const short CS_SERVER_KEY_EXCHANGE = 6;

	protected const short CS_CERTIFICATE_REQUEST = 7;

	protected const short CS_SERVER_HELLO_DONE = 8;

	protected const short CS_CLIENT_SUPPLEMENTAL_DATA = 9;

	protected const short CS_CLIENT_CERTIFICATE = 10;

	protected const short CS_CLIENT_KEY_EXCHANGE = 11;

	protected const short CS_CERTIFICATE_VERIFY = 12;

	protected const short CS_CLIENT_FINISHED = 13;

	protected const short CS_SERVER_SESSION_TICKET = 14;

	protected const short CS_SERVER_FINISHED = 15;

	protected const short CS_END = 16;

	protected const short ADS_MODE_1_Nsub1 = 0;

	protected const short ADS_MODE_0_N = 1;

	protected const short ADS_MODE_0_N_FIRSTONLY = 2;

	private ByteQueue mApplicationDataQueue = new ByteQueue(0);

	private ByteQueue mAlertQueue = new ByteQueue(2);

	private ByteQueue mHandshakeQueue = new ByteQueue(0);

	internal RecordStream mRecordStream;

	protected SecureRandom mSecureRandom;

	private TlsStream mTlsStream = null;

	private volatile bool mClosed = false;

	private volatile bool mFailedWithError = false;

	private volatile bool mAppDataReady = false;

	private volatile bool mAppDataSplitEnabled = true;

	private volatile int mAppDataSplitMode = 0;

	private byte[] mExpectedVerifyData = null;

	protected TlsSession mTlsSession = null;

	protected SessionParameters mSessionParameters = null;

	protected SecurityParameters mSecurityParameters = null;

	protected Certificate mPeerCertificate = null;

	protected int[] mOfferedCipherSuites = null;

	protected byte[] mOfferedCompressionMethods = null;

	protected IDictionary mClientExtensions = null;

	protected IDictionary mServerExtensions = null;

	protected short mConnectionState = 0;

	protected bool mResumedSession = false;

	protected bool mReceivedChangeCipherSpec = false;

	protected bool mSecureRenegotiation = false;

	protected bool mAllowCertificateStatus = false;

	protected bool mExpectSessionTicket = false;

	protected bool mBlocking = true;

	protected ByteQueueStream mInputBuffers = null;

	protected ByteQueueStream mOutputBuffer = null;

	protected abstract TlsContext Context { get; }

	internal abstract AbstractTlsContext ContextAdmin { get; }

	protected abstract TlsPeer Peer { get; }

	public virtual Stream Stream
	{
		get
		{
			if (!mBlocking)
			{
				throw new InvalidOperationException("Cannot use Stream in non-blocking mode! Use OfferInput()/OfferOutput() instead.");
			}
			return mTlsStream;
		}
	}

	public virtual bool IsClosed => mClosed;

	public TlsProtocol(Stream stream, SecureRandom secureRandom)
		: this(stream, stream, secureRandom)
	{
	}

	public TlsProtocol(Stream input, Stream output, SecureRandom secureRandom)
	{
		mRecordStream = new RecordStream(this, input, output);
		mSecureRandom = secureRandom;
	}

	public TlsProtocol(SecureRandom secureRandom)
	{
		mBlocking = false;
		mInputBuffers = new ByteQueueStream();
		mOutputBuffer = new ByteQueueStream();
		mRecordStream = new RecordStream(this, mInputBuffers, mOutputBuffer);
		mSecureRandom = secureRandom;
	}

	protected virtual void HandleAlertMessage(byte alertLevel, byte alertDescription)
	{
		Peer.NotifyAlertReceived(alertLevel, alertDescription);
		if (alertLevel == 1)
		{
			HandleAlertWarningMessage(alertDescription);
			return;
		}
		HandleFailure();
		throw new TlsFatalAlertReceived(alertDescription);
	}

	protected virtual void HandleAlertWarningMessage(byte alertDescription)
	{
		if (alertDescription == 0)
		{
			if (!mAppDataReady)
			{
				throw new TlsFatalAlert(40);
			}
			HandleClose(user_canceled: false);
		}
	}

	protected virtual void HandleChangeCipherSpecMessage()
	{
	}

	protected virtual void HandleClose(bool user_canceled)
	{
		if (!mClosed)
		{
			mClosed = true;
			if (user_canceled && !mAppDataReady)
			{
				RaiseAlertWarning(90, "User canceled handshake");
			}
			RaiseAlertWarning(0, "Connection closed");
			mRecordStream.SafeClose();
			if (!mAppDataReady)
			{
				CleanupHandshake();
			}
		}
	}

	protected virtual void HandleException(byte alertDescription, string message, Exception cause)
	{
		if (!mClosed)
		{
			RaiseAlertFatal(alertDescription, message, cause);
			HandleFailure();
		}
	}

	protected virtual void HandleFailure()
	{
		mClosed = true;
		mFailedWithError = true;
		InvalidateSession();
		mRecordStream.SafeClose();
		if (!mAppDataReady)
		{
			CleanupHandshake();
		}
	}

	protected abstract void HandleHandshakeMessage(byte type, MemoryStream buf);

	protected virtual void ApplyMaxFragmentLengthExtension()
	{
		if (mSecurityParameters.maxFragmentLength >= 0)
		{
			if (!MaxFragmentLength.IsValid((byte)mSecurityParameters.maxFragmentLength))
			{
				throw new TlsFatalAlert(80);
			}
			int plaintextLimit = 1 << 8 + mSecurityParameters.maxFragmentLength;
			mRecordStream.SetPlaintextLimit(plaintextLimit);
		}
	}

	protected virtual void CheckReceivedChangeCipherSpec(bool expected)
	{
		if (expected != mReceivedChangeCipherSpec)
		{
			throw new TlsFatalAlert(10);
		}
	}

	protected virtual void CleanupHandshake()
	{
		if (mExpectedVerifyData != null)
		{
			Arrays.Fill(mExpectedVerifyData, 0);
			mExpectedVerifyData = null;
		}
		mSecurityParameters.Clear();
		mPeerCertificate = null;
		mOfferedCipherSuites = null;
		mOfferedCompressionMethods = null;
		mClientExtensions = null;
		mServerExtensions = null;
		mResumedSession = false;
		mReceivedChangeCipherSpec = false;
		mSecureRenegotiation = false;
		mAllowCertificateStatus = false;
		mExpectSessionTicket = false;
	}

	protected virtual void BlockForHandshake()
	{
		if (!mBlocking)
		{
			return;
		}
		while (mConnectionState != 16)
		{
			if (mClosed)
			{
				throw new TlsFatalAlert(80);
			}
			SafeReadRecord();
		}
	}

	protected virtual void CompleteHandshake()
	{
		try
		{
			mConnectionState = 16;
			mAlertQueue.Shrink();
			mHandshakeQueue.Shrink();
			mRecordStream.FinaliseHandshake();
			mAppDataSplitEnabled = !TlsUtilities.IsTlsV11(Context);
			if (!mAppDataReady)
			{
				mAppDataReady = true;
				if (mBlocking)
				{
					mTlsStream = new TlsStream(this);
				}
			}
			if (mTlsSession != null)
			{
				if (mSessionParameters == null)
				{
					mSessionParameters = new SessionParameters.Builder().SetCipherSuite(mSecurityParameters.CipherSuite).SetCompressionAlgorithm(mSecurityParameters.CompressionAlgorithm).SetExtendedMasterSecret(mSecurityParameters.IsExtendedMasterSecret)
						.SetMasterSecret(mSecurityParameters.MasterSecret)
						.SetPeerCertificate(mPeerCertificate)
						.SetPskIdentity(mSecurityParameters.PskIdentity)
						.SetSrpIdentity(mSecurityParameters.SrpIdentity)
						.SetServerExtensions(mServerExtensions)
						.Build();
					mTlsSession = new TlsSessionImpl(mTlsSession.SessionID, mSessionParameters);
				}
				ContextAdmin.SetResumableSession(mTlsSession);
			}
			Peer.NotifyHandshakeComplete();
		}
		finally
		{
			CleanupHandshake();
		}
	}

	protected internal void ProcessRecord(byte protocol, byte[] buf, int off, int len)
	{
		switch (protocol)
		{
		case 21:
			mAlertQueue.AddData(buf, off, len);
			ProcessAlertQueue();
			break;
		case 23:
			if (!mAppDataReady)
			{
				throw new TlsFatalAlert(10);
			}
			mApplicationDataQueue.AddData(buf, off, len);
			ProcessApplicationDataQueue();
			break;
		case 20:
			ProcessChangeCipherSpec(buf, off, len);
			break;
		case 22:
		{
			if (mHandshakeQueue.Available > 0)
			{
				mHandshakeQueue.AddData(buf, off, len);
				ProcessHandshakeQueue(mHandshakeQueue);
				break;
			}
			ByteQueue byteQueue = new ByteQueue(buf, off, len);
			ProcessHandshakeQueue(byteQueue);
			int available = byteQueue.Available;
			if (available > 0)
			{
				mHandshakeQueue.AddData(buf, off + len - available, available);
			}
			break;
		}
		default:
			throw new TlsFatalAlert(80);
		}
	}

	private void ProcessHandshakeQueue(ByteQueue queue)
	{
		while (queue.Available >= 4)
		{
			byte[] buf = new byte[4];
			queue.Read(buf, 0, 4, 0);
			byte b = TlsUtilities.ReadUint8(buf, 0);
			int num = TlsUtilities.ReadUint24(buf, 1);
			int num2 = 4 + num;
			if (queue.Available < num2)
			{
				break;
			}
			if (b != 0)
			{
				if (20 == b)
				{
					CheckReceivedChangeCipherSpec(expected: true);
					TlsContext context = Context;
					if (mExpectedVerifyData == null && context.SecurityParameters.MasterSecret != null)
					{
						mExpectedVerifyData = CreateVerifyData(!context.IsServer);
					}
				}
				else
				{
					CheckReceivedChangeCipherSpec(mConnectionState == 16);
				}
				queue.CopyTo(mRecordStream.HandshakeHashUpdater, num2);
			}
			queue.RemoveData(4);
			MemoryStream buf2 = queue.ReadFrom(num);
			HandleHandshakeMessage(b, buf2);
		}
	}

	private void ProcessApplicationDataQueue()
	{
	}

	private void ProcessAlertQueue()
	{
		while (mAlertQueue.Available >= 2)
		{
			byte[] array = mAlertQueue.RemoveData(2, 0);
			byte alertLevel = array[0];
			byte alertDescription = array[1];
			HandleAlertMessage(alertLevel, alertDescription);
		}
	}

	private void ProcessChangeCipherSpec(byte[] buf, int off, int len)
	{
		for (int i = 0; i < len; i++)
		{
			byte b = TlsUtilities.ReadUint8(buf, off + i);
			if (b != 1)
			{
				throw new TlsFatalAlert(50);
			}
			if (mReceivedChangeCipherSpec || mAlertQueue.Available > 0 || mHandshakeQueue.Available > 0)
			{
				throw new TlsFatalAlert(10);
			}
			mRecordStream.ReceivedReadCipherSpec();
			mReceivedChangeCipherSpec = true;
			HandleChangeCipherSpecMessage();
		}
	}

	protected internal virtual int ApplicationDataAvailable()
	{
		return mApplicationDataQueue.Available;
	}

	protected internal virtual int ReadApplicationData(byte[] buf, int offset, int len)
	{
		if (len < 1)
		{
			return 0;
		}
		while (mApplicationDataQueue.Available == 0)
		{
			if (mClosed)
			{
				if (mFailedWithError)
				{
					throw new IOException("Cannot read application data on failed TLS connection");
				}
				if (!mAppDataReady)
				{
					throw new InvalidOperationException("Cannot read application data until initial handshake completed.");
				}
				return 0;
			}
			SafeReadRecord();
		}
		len = System.Math.Min(len, mApplicationDataQueue.Available);
		mApplicationDataQueue.RemoveData(buf, offset, len, 0);
		return len;
	}

	protected virtual void SafeCheckRecordHeader(byte[] recordHeader)
	{
		try
		{
			mRecordStream.CheckRecordHeader(recordHeader);
		}
		catch (TlsFatalAlert tlsFatalAlert)
		{
			HandleException(tlsFatalAlert.AlertDescription, "Failed to read record", tlsFatalAlert);
			throw tlsFatalAlert;
		}
		catch (IOException ex)
		{
			HandleException(80, "Failed to read record", ex);
			throw ex;
		}
		catch (Exception ex2)
		{
			HandleException(80, "Failed to read record", ex2);
			throw new TlsFatalAlert(80, ex2);
		}
	}

	protected virtual void SafeReadRecord()
	{
		try
		{
			if (mRecordStream.ReadRecord())
			{
				return;
			}
			if (!mAppDataReady)
			{
				throw new TlsFatalAlert(40);
			}
		}
		catch (TlsFatalAlertReceived tlsFatalAlertReceived)
		{
			throw tlsFatalAlertReceived;
		}
		catch (TlsFatalAlert tlsFatalAlert)
		{
			HandleException(tlsFatalAlert.AlertDescription, "Failed to read record", tlsFatalAlert);
			throw tlsFatalAlert;
		}
		catch (IOException ex)
		{
			HandleException(80, "Failed to read record", ex);
			throw ex;
		}
		catch (Exception ex2)
		{
			HandleException(80, "Failed to read record", ex2);
			throw new TlsFatalAlert(80, ex2);
		}
		HandleFailure();
		throw new TlsNoCloseNotifyException();
	}

	protected virtual void SafeWriteRecord(byte type, byte[] buf, int offset, int len)
	{
		try
		{
			mRecordStream.WriteRecord(type, buf, offset, len);
		}
		catch (TlsFatalAlert tlsFatalAlert)
		{
			HandleException(tlsFatalAlert.AlertDescription, "Failed to write record", tlsFatalAlert);
			throw tlsFatalAlert;
		}
		catch (IOException ex)
		{
			HandleException(80, "Failed to write record", ex);
			throw ex;
		}
		catch (Exception ex2)
		{
			HandleException(80, "Failed to write record", ex2);
			throw new TlsFatalAlert(80, ex2);
		}
	}

	protected internal virtual void WriteData(byte[] buf, int offset, int len)
	{
		if (mClosed)
		{
			throw new IOException("Cannot write application data on closed/failed TLS connection");
		}
		while (len > 0)
		{
			if (mAppDataSplitEnabled)
			{
				switch (mAppDataSplitMode)
				{
				case 1:
					SafeWriteRecord(23, TlsUtilities.EmptyBytes, 0, 0);
					break;
				case 2:
					mAppDataSplitEnabled = false;
					SafeWriteRecord(23, TlsUtilities.EmptyBytes, 0, 0);
					break;
				default:
					SafeWriteRecord(23, buf, offset, 1);
					offset++;
					len--;
					break;
				}
			}
			if (len > 0)
			{
				int num = System.Math.Min(len, mRecordStream.GetPlaintextLimit());
				SafeWriteRecord(23, buf, offset, num);
				offset += num;
				len -= num;
			}
		}
	}

	protected virtual void SetAppDataSplitMode(int appDataSplitMode)
	{
		if (appDataSplitMode < 0 || appDataSplitMode > 2)
		{
			throw new ArgumentException("Illegal appDataSplitMode mode: " + appDataSplitMode, "appDataSplitMode");
		}
		mAppDataSplitMode = appDataSplitMode;
	}

	protected virtual void WriteHandshakeMessage(byte[] buf, int off, int len)
	{
		if (len < 4)
		{
			throw new TlsFatalAlert(80);
		}
		if (TlsUtilities.ReadUint8(buf, off) != 0)
		{
			mRecordStream.HandshakeHashUpdater.Write(buf, off, len);
		}
		int num = 0;
		do
		{
			int num2 = System.Math.Min(len - num, mRecordStream.GetPlaintextLimit());
			SafeWriteRecord(22, buf, off + num, num2);
			num += num2;
		}
		while (num < len);
	}

	public virtual void CloseInput()
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use CloseInput() in blocking mode!");
		}
		if (mClosed)
		{
			return;
		}
		if (mInputBuffers.Available > 0)
		{
			throw new EndOfStreamException();
		}
		if (!mAppDataReady)
		{
			throw new TlsFatalAlert(40);
		}
		throw new TlsNoCloseNotifyException();
	}

	public virtual void OfferInput(byte[] input)
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use OfferInput() in blocking mode! Use Stream instead.");
		}
		if (mClosed)
		{
			throw new IOException("Connection is closed, cannot accept any more input");
		}
		mInputBuffers.Write(input);
		while (mInputBuffers.Available >= 5)
		{
			byte[] array = new byte[5];
			mInputBuffers.Peek(array);
			int num = TlsUtilities.ReadUint16(array, 3) + 5;
			if (mInputBuffers.Available < num)
			{
				SafeCheckRecordHeader(array);
				break;
			}
			SafeReadRecord();
			if (mClosed)
			{
				if (mConnectionState != 16)
				{
					throw new TlsFatalAlert(80);
				}
				break;
			}
		}
	}

	public virtual int GetAvailableInputBytes()
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use GetAvailableInputBytes() in blocking mode! Use ApplicationDataAvailable() instead.");
		}
		return ApplicationDataAvailable();
	}

	public virtual int ReadInput(byte[] buffer, int offset, int length)
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use ReadInput() in blocking mode! Use Stream instead.");
		}
		return ReadApplicationData(buffer, offset, System.Math.Min(length, ApplicationDataAvailable()));
	}

	public virtual void OfferOutput(byte[] buffer, int offset, int length)
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use OfferOutput() in blocking mode! Use Stream instead.");
		}
		if (!mAppDataReady)
		{
			throw new IOException("Application data cannot be sent until the handshake is complete!");
		}
		WriteData(buffer, offset, length);
	}

	public virtual int GetAvailableOutputBytes()
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use GetAvailableOutputBytes() in blocking mode! Use Stream instead.");
		}
		return mOutputBuffer.Available;
	}

	public virtual int ReadOutput(byte[] buffer, int offset, int length)
	{
		if (mBlocking)
		{
			throw new InvalidOperationException("Cannot use ReadOutput() in blocking mode! Use Stream instead.");
		}
		return mOutputBuffer.Read(buffer, offset, length);
	}

	protected virtual void InvalidateSession()
	{
		if (mSessionParameters != null)
		{
			mSessionParameters.Clear();
			mSessionParameters = null;
		}
		if (mTlsSession != null)
		{
			mTlsSession.Invalidate();
			mTlsSession = null;
		}
	}

	protected virtual void ProcessFinishedMessage(MemoryStream buf)
	{
		if (mExpectedVerifyData == null)
		{
			throw new TlsFatalAlert(80);
		}
		byte[] b = TlsUtilities.ReadFully(mExpectedVerifyData.Length, buf);
		AssertEmpty(buf);
		if (!Arrays.ConstantTimeAreEqual(mExpectedVerifyData, b))
		{
			throw new TlsFatalAlert(51);
		}
	}

	protected virtual void RaiseAlertFatal(byte alertDescription, string message, Exception cause)
	{
		Peer.NotifyAlertRaised(2, alertDescription, message, cause);
		byte[] plaintext = new byte[2] { 2, alertDescription };
		try
		{
			mRecordStream.WriteRecord(21, plaintext, 0, 2);
		}
		catch (Exception)
		{
		}
	}

	protected virtual void RaiseAlertWarning(byte alertDescription, string message)
	{
		Peer.NotifyAlertRaised(1, alertDescription, message, null);
		byte[] buf = new byte[2] { 1, alertDescription };
		SafeWriteRecord(21, buf, 0, 2);
	}

	protected virtual void SendCertificateMessage(Certificate certificate)
	{
		if (certificate == null)
		{
			certificate = Certificate.EmptyChain;
		}
		if (certificate.IsEmpty)
		{
			TlsContext context = Context;
			if (!context.IsServer)
			{
				ProtocolVersion serverVersion = Context.ServerVersion;
				if (serverVersion.IsSsl)
				{
					string message = serverVersion.ToString() + " client didn't provide credentials";
					RaiseAlertWarning(41, message);
					return;
				}
			}
		}
		HandshakeMessage handshakeMessage = new HandshakeMessage(11);
		certificate.Encode(handshakeMessage);
		handshakeMessage.WriteToRecordStream(this);
	}

	protected virtual void SendChangeCipherSpecMessage()
	{
		byte[] array = new byte[1] { 1 };
		SafeWriteRecord(20, array, 0, array.Length);
		mRecordStream.SentWriteCipherSpec();
	}

	protected virtual void SendFinishedMessage()
	{
		byte[] array = CreateVerifyData(Context.IsServer);
		HandshakeMessage handshakeMessage = new HandshakeMessage(20, array.Length);
		handshakeMessage.Write(array, 0, array.Length);
		handshakeMessage.WriteToRecordStream(this);
	}

	protected virtual void SendSupplementalDataMessage(IList supplementalData)
	{
		HandshakeMessage handshakeMessage = new HandshakeMessage(23);
		WriteSupplementalData(handshakeMessage, supplementalData);
		handshakeMessage.WriteToRecordStream(this);
	}

	protected virtual byte[] CreateVerifyData(bool isServer)
	{
		TlsContext context = Context;
		string asciiLabel = (isServer ? "server finished" : "client finished");
		byte[] sslSender = (isServer ? TlsUtilities.SSL_SERVER : TlsUtilities.SSL_CLIENT);
		byte[] currentPrfHash = GetCurrentPrfHash(context, mRecordStream.HandshakeHash, sslSender);
		return TlsUtilities.CalculateVerifyData(context, asciiLabel, currentPrfHash);
	}

	public virtual void Close()
	{
		HandleClose(user_canceled: true);
	}

	protected internal virtual void Flush()
	{
		mRecordStream.Flush();
	}

	protected virtual short ProcessMaxFragmentLengthExtension(IDictionary clientExtensions, IDictionary serverExtensions, byte alertDescription)
	{
		short maxFragmentLengthExtension = TlsExtensionsUtilities.GetMaxFragmentLengthExtension(serverExtensions);
		if (maxFragmentLengthExtension >= 0 && (!MaxFragmentLength.IsValid((byte)maxFragmentLengthExtension) || (!mResumedSession && maxFragmentLengthExtension != TlsExtensionsUtilities.GetMaxFragmentLengthExtension(clientExtensions))))
		{
			throw new TlsFatalAlert(alertDescription);
		}
		return maxFragmentLengthExtension;
	}

	protected virtual void RefuseRenegotiation()
	{
		if (TlsUtilities.IsSsl(Context))
		{
			throw new TlsFatalAlert(40);
		}
		RaiseAlertWarning(100, "Renegotiation not supported");
	}

	protected internal static void AssertEmpty(MemoryStream buf)
	{
		if (buf.Position < buf.Length)
		{
			throw new TlsFatalAlert(50);
		}
	}

	protected internal static byte[] CreateRandomBlock(bool useGmtUnixTime, IRandomGenerator randomGenerator)
	{
		byte[] array = new byte[32];
		randomGenerator.NextBytes(array);
		if (useGmtUnixTime)
		{
			TlsUtilities.WriteGmtUnixTime(array, 0);
		}
		return array;
	}

	protected internal static byte[] CreateRenegotiationInfo(byte[] renegotiated_connection)
	{
		return TlsUtilities.EncodeOpaque8(renegotiated_connection);
	}

	protected internal static void EstablishMasterSecret(TlsContext context, TlsKeyExchange keyExchange)
	{
		byte[] array = keyExchange.GeneratePremasterSecret();
		try
		{
			context.SecurityParameters.masterSecret = TlsUtilities.CalculateMasterSecret(context, array);
		}
		finally
		{
			if (array != null)
			{
				Arrays.Fill(array, 0);
			}
		}
	}

	protected internal static byte[] GetCurrentPrfHash(TlsContext context, TlsHandshakeHash handshakeHash, byte[] sslSender)
	{
		IDigest digest = handshakeHash.ForkPrfHash();
		if (sslSender != null && TlsUtilities.IsSsl(context))
		{
			digest.BlockUpdate(sslSender, 0, sslSender.Length);
		}
		return DigestUtilities.DoFinal(digest);
	}

	protected internal static IDictionary ReadExtensions(MemoryStream input)
	{
		if (input.Position >= input.Length)
		{
			return null;
		}
		byte[] buffer = TlsUtilities.ReadOpaque16(input);
		AssertEmpty(input);
		MemoryStream memoryStream = new MemoryStream(buffer, writable: false);
		IDictionary dictionary = Platform.CreateHashtable();
		while (memoryStream.Position < memoryStream.Length)
		{
			int num = TlsUtilities.ReadUint16(memoryStream);
			byte[] value = TlsUtilities.ReadOpaque16(memoryStream);
			if (dictionary.Contains(num))
			{
				throw new TlsFatalAlert(47);
			}
			dictionary.Add(num, value);
		}
		return dictionary;
	}

	protected internal static IList ReadSupplementalDataMessage(MemoryStream input)
	{
		byte[] buffer = TlsUtilities.ReadOpaque24(input);
		AssertEmpty(input);
		MemoryStream memoryStream = new MemoryStream(buffer, writable: false);
		IList list = Platform.CreateArrayList();
		while (memoryStream.Position < memoryStream.Length)
		{
			int dataType = TlsUtilities.ReadUint16(memoryStream);
			byte[] data = TlsUtilities.ReadOpaque16(memoryStream);
			list.Add(new SupplementalDataEntry(dataType, data));
		}
		return list;
	}

	protected internal static void WriteExtensions(Stream output, IDictionary extensions)
	{
		MemoryStream memoryStream = new MemoryStream();
		WriteSelectedExtensions(memoryStream, extensions, selectEmpty: true);
		WriteSelectedExtensions(memoryStream, extensions, selectEmpty: false);
		byte[] buf = memoryStream.ToArray();
		TlsUtilities.WriteOpaque16(buf, output);
	}

	protected internal static void WriteSelectedExtensions(Stream output, IDictionary extensions, bool selectEmpty)
	{
		foreach (object key in extensions.Keys)
		{
			int num = (int)key;
			byte[] array = (byte[])extensions[num];
			if (selectEmpty == (array.Length == 0))
			{
				TlsUtilities.CheckUint16(num);
				TlsUtilities.WriteUint16(num, output);
				TlsUtilities.WriteOpaque16(array, output);
			}
		}
	}

	protected internal static void WriteSupplementalData(Stream output, IList supplementalData)
	{
		MemoryStream memoryStream = new MemoryStream();
		foreach (SupplementalDataEntry supplementalDatum in supplementalData)
		{
			int dataType = supplementalDatum.DataType;
			TlsUtilities.CheckUint16(dataType);
			TlsUtilities.WriteUint16(dataType, memoryStream);
			TlsUtilities.WriteOpaque16(supplementalDatum.Data, memoryStream);
		}
		byte[] buf = memoryStream.ToArray();
		TlsUtilities.WriteOpaque24(buf, output);
	}

	protected internal static int GetPrfAlgorithm(TlsContext context, int ciphersuite)
	{
		bool flag = TlsUtilities.IsTlsV12(context);
		switch (ciphersuite)
		{
		case 59:
		case 60:
		case 61:
		case 62:
		case 63:
		case 64:
		case 103:
		case 104:
		case 105:
		case 106:
		case 107:
		case 108:
		case 109:
		case 156:
		case 158:
		case 160:
		case 162:
		case 164:
		case 166:
		case 168:
		case 170:
		case 172:
		case 186:
		case 187:
		case 188:
		case 189:
		case 190:
		case 191:
		case 192:
		case 193:
		case 194:
		case 195:
		case 196:
		case 197:
		case 49187:
		case 49189:
		case 49191:
		case 49193:
		case 49195:
		case 49197:
		case 49199:
		case 49201:
		case 49266:
		case 49268:
		case 49270:
		case 49272:
		case 49274:
		case 49276:
		case 49278:
		case 49280:
		case 49282:
		case 49284:
		case 49286:
		case 49288:
		case 49290:
		case 49292:
		case 49294:
		case 49296:
		case 49298:
		case 49308:
		case 49309:
		case 49310:
		case 49311:
		case 49312:
		case 49313:
		case 49314:
		case 49315:
		case 49316:
		case 49317:
		case 49318:
		case 49319:
		case 49320:
		case 49321:
		case 49322:
		case 49323:
		case 49324:
		case 49325:
		case 49326:
		case 49327:
		case 52392:
		case 52393:
		case 52394:
		case 52395:
		case 52396:
		case 52397:
		case 52398:
		case 65280:
		case 65281:
		case 65282:
		case 65283:
		case 65284:
		case 65285:
		case 65296:
		case 65297:
		case 65298:
		case 65299:
		case 65300:
		case 65301:
			if (flag)
			{
				return 1;
			}
			throw new TlsFatalAlert(47);
		case 157:
		case 159:
		case 161:
		case 163:
		case 165:
		case 167:
		case 169:
		case 171:
		case 173:
		case 49188:
		case 49190:
		case 49192:
		case 49194:
		case 49196:
		case 49198:
		case 49200:
		case 49202:
		case 49267:
		case 49269:
		case 49271:
		case 49273:
		case 49275:
		case 49277:
		case 49279:
		case 49281:
		case 49283:
		case 49285:
		case 49287:
		case 49289:
		case 49291:
		case 49293:
		case 49295:
		case 49297:
		case 49299:
			if (flag)
			{
				return 2;
			}
			throw new TlsFatalAlert(47);
		case 175:
		case 177:
		case 179:
		case 181:
		case 183:
		case 185:
		case 49208:
		case 49211:
		case 49301:
		case 49303:
		case 49305:
		case 49307:
			if (flag)
			{
				return 2;
			}
			return 0;
		default:
			if (flag)
			{
				return 1;
			}
			return 0;
		}
	}
}