private static void Server_MessageArrive(object sender, MessageArriveArgs e)
{
Console.WriteLine("[S] Received: " + Encoding.UTF8.GetString(e.Content.Array, e.Content.Offset, e.Content.Count));
// 如果是收到的第一个消息，则开始加密
if (!e.Session.IsEncrypted) {
var splited = Encoding.UTF8.GetString(e.Content.Array, e.Content.Offset, e.Content.Count).Split('*');
e.Session.AesIV = Convert.FromBase64String(splited[0]);
e.Session.AesKey = Convert.FromBase64String(splited[1]);
e.Session.IsEncrypted = true;
e.Session.Send(e.Content.Array, 0, e.Content.Count, replyToMessage: e);
}
else {
var p = int.Parse(Encoding.UTF8.GetString(e.Content.Array, e.Content.Offset, e.Content.Count));
var dataHello = Encoding.UTF8.GetBytes((p * p).ToString());
e.Session.Send(dataHello, 0, dataHello.Length, replyToMessage: e);
}
}
private void Client_MessageArrive(object sender, MessageArriveArgs e)
{
Console.WriteLine("[C] Received: " + Encoding.UTF8.GetString(e.Content.Array, e.Content.Offset, e.Content.Count));
}
/// <summary>
/// 向远端发送数据。
/// </summary>
/// <param name="data"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
internal ArraySegment<byte>? Send(byte[] data, int offset, int count, MessageArriveArgs replyToMessage = null, Action<ArraySegment<byte>> replyCallback = null, bool block = false, MessageFlags extraFlags = MessageFlags.None) {
if (socket == null) throw new Exception("连接已经断开或尚未打开");
if (replyToMessage != null && replyToMessage.HasReplied) throw new Exception("不能重复回复消息");
if (data == null) throw new ArgumentNullException(nameof(data));
if (offset < 0 || offset >= data.Length) throw new ArgumentOutOfRangeException(nameof(offset));
if (count <= 0 || offset + count > data.Length) throw new ArgumentOutOfRangeException(nameof(count));
if (replyCallback != null && replyToMessage != null) throw new ArgumentException("回复消息时不能再接受回复");
if (block && replyToMessage != null) throw new ArgumentException("回复消息时不能再接受回复");
if (block && replyCallback != null) throw new ArgumentException("使用阻塞模式时不能设置 callback");
lock (lockerSend) {
try {
MessageFlags flags = MessageFlags.None | extraFlags;
short mid;
if (replyToMessage != null) {
flags |= MessageFlags.Response;
mid = replyToMessage.MessageID;
}
else {
flags |= MessageFlags.Request;
mid = currentMessageID;
}
// 获取正文
ArraySegment<byte> contentToSend;
if (IsEncrypted == false) {
contentToSend = new ArraySegment<byte>(data, offset, count);
}
else {
// 加密要发送的数据
initEncryption();
contentToSend = new ArraySegment<byte>(aesEncoder.TransformFinalBlock(data, offset, count));
}
BitConverter.GetBytes(System.Net.IPAddress.HostToNetworkOrder(contentToSend.Count + 4)).CopyTo(headerBuffer, 0);
BitConverter.GetBytes(System.Net.IPAddress.HostToNetworkOrder((short)flags)).CopyTo(headerBuffer, 4);
BitConverter.GetBytes(System.Net.IPAddress.HostToNetworkOrder(mid)).CopyTo(headerBuffer, 6);
// 如果带有 callback，则进行处理
if (replyCallback != null || block) {
if (this.waitHandles[mid] == null) {
this.waitHandles[mid] = new object();
}
if (replyCallback != null) {
ThreadPool.QueueUserWorkItem(o => {
var id = (short)o;
lock (waitHandles[id]) {
if (Monitor.Wait(waitHandles[id], ReceiveReplyTimeout)) {
replyCallback(this.replyArrays[id]);
replyArrays[id] = new ArraySegment<byte>(); // 清理内存
}
}
}, mid);
}
}
try {
socket.Send(new ArraySegment<byte>[] { new ArraySegment<byte>(headerBuffer), contentToSend });
}
catch {
closeSocket();
throw new Exception("连接已经断开");
}
// 如果是阻塞模式，则等待
if (block) {
lock (waitHandles[mid]) {
if (Monitor.Wait(waitHandles[mid], ReceiveReplyTimeout)) {
var ret = replyArrays[mid];
replyArrays[mid] = new ArraySegment<byte>(); // 清理内存
return ret;
}
}
throw new TimeoutException("等待远端回复超时。");
}
return null;
}
finally {
if (replyToMessage == null) {
if (currentMessageID == short.MaxValue - 1)
currentMessageID = 0;
else
currentMessageID++;
}
}
}
}
private void processData(byte[] receivedData, int offset, int length) {
// 获取消息的基本属性
var flags = (MessageFlags)IPAddress.NetworkToHostOrder(BitConverter.ToInt16(receivedData, offset));
var mid = IPAddress.NetworkToHostOrder(BitConverter.ToInt16(receivedData, offset + sizeof(short)));
// 将正文消息封装给客户端处理，并允许客户端回复
var buffer = new byte[length - 4];
Array.Copy(receivedData, offset + 4, buffer, 0, length - 4);
if (IsEncrypted) {
// 如果此消息被加密，则解密
initEncryption();
buffer = aes.CreateDecryptor().TransformFinalBlock(buffer, 0, buffer.Length);
}
if ((flags & MessageFlags.Request) == MessageFlags.Request) {
// 对于请求，调用用户的相关功能
var arg = new MessageArriveArgs(null, mid, buffer, 0, buffer.Length);
if (MessageArrive != null) {
ThreadPool.QueueUserWorkItem(o => {
waitHandle.WaitOne();
try {
MessageArrive(this, arg);
}
catch {
}
finally {
waitHandle.Set();
}
});
}
}
else {
// 对于回复消息，触发相关的事件
if (waitHandles[mid] != null) {
replyArrays[mid] = new ArraySegment<byte>(buffer);
lock (waitHandles[mid])
Monitor.Pulse(waitHandles[mid]);
}
}
}
/// <summary>
/// 向远端发送数据。
/// </summary>
/// <param name="data"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
public ArraySegment<byte>? Send(byte[] data, int offset, int count, MessageArriveArgs replyToMessage = null, Action<ArraySegment<byte>> replyCallback = null, bool block = false) {
return Send(data, offset, count, replyToMessage, replyCallback, block, MessageFlags.None);
}
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;
}
}
