private bool ProcessData(TcpServerUserSession session, byte[] receivedData, int offset, int length) {
try {
// 首先读取头部信息，以确定所传输的数据特征
var flags = (MessageFlags)(System.Net.IPAddress.NetworkToHostOrder(BitConverter.ToInt16(receivedData, offset)));
var isReply = (flags & MessageFlags.Response) == MessageFlags.Response;
// 获取消息号
var messageID = System.Net.IPAddress.NetworkToHostOrder(BitConverter.ToInt16(receivedData, offset + sizeof(short)));
// 进行处理，将数据拷贝以防止缓冲区覆盖
var buffer = new byte[length - sizeof(short) * 2];
Array.Copy(receivedData, offset + sizeof(short) * 2, buffer, 0, buffer.Length);
if (session.IsEncrypted) {
// 对于已经加密的内容，要进行解密
session.initEncryption();
buffer = session.aes.CreateDecryptor().TransformFinalBlock(buffer, 0, buffer.Length);
}
if (!isReply) {
var args = new MessageArriveArgs(session, messageID, buffer, 0, buffer.Length);
if ((flags & MessageFlags.InternalCalls) == MessageFlags.InternalCalls) {
// 如果是内部指令，可以直接在内部处理
if (buffer[0] == (byte)InternalCalls.RequestRSAPublicKey) {
// 发送 RSA 公钥
session.SendAndForget(Encoding.UTF8.GetBytes(rsa.ToXmlString(false)), args);
}
else if (buffer[0] == (byte)InternalCalls.SendAESKeysViaRSA) {
if (rsa == null) {
session.SendAndForget(new byte[] { 1 }, args);
}
else {
// 解析 AES Key 和 IV，然后开始加密对话
var aesKeyAndIV = rsa.Decrypt(buffer.Skip(1).ToArray(), true);
session.AesKey = aesKeyAndIV.Take(16).ToArray();
session.AesIV = aesKeyAndIV.Skip(16).Take(16).ToArray();
session.SendAndForget(new byte[] { 0 }, args);
session.IsEncrypted = true;
}
}
}
else {
ThreadPool.QueueUserWorkItem(o => {
maxCountOfConcurrentDataProccesserLimiter.WaitOne();
try {
if (this.MessageArrive != null) {
MessageArrive(this, args);
}
}
catch {
session.Dispose();
}
finally {
maxCountOfConcurrentDataProccesserLimiter.Release();
}
});
}
return true;
}
else {
// 对于回复，首先判断是否有等待的句柄
if (session.waitHandles[messageID] == null)
return true;
// 设置参数
session.replyArrays[messageID] = new ArraySegment<byte>(buffer, 0, buffer.Length);
// 如果有等待句柄，则通知事件
lock (session.waitHandles[messageID])
Monitor.Pulse(session.waitHandles[messageID]);
return true;
}
}
catch {
return false;
}
}
internal MessageArriveArgs(TcpServerUserSession session, short id, byte[] arr, int offset, int length) {
Session = session;
MessageID = id;
Content = new ArraySegment<byte>(arr, offset, length);
}
private void ProcessAccept(SocketAsyncEventArgs acceptEventArgs) {
if (acceptEventArgs.SocketError != SocketError.Success) {
CloseConnection(acceptEventArgs);
listenForConnectionAsync(acceptEventArgs);
return;
}
// 继续监听下一个连接请求
var accessSocket = acceptEventArgs.AcceptSocket;
acceptEventArgs.AcceptSocket = null;
listenForConnectionAsync(acceptEventArgs);
// 增加客户端数量
changeClientCount(1);
// 为客户端创建一个 Session
var session = new TcpServerUserSession(this, accessSocket, accessSocket.RemoteEndPoint);
session.receiveArgs.Completed += ReceiveComplete_Callback;
// 将 Session 放入客户端列表
lock (sessions)
sessions.Add(session);
// 开始接收客户端数据
BeginReceive(session.receiveArgs);
}
