C# P2P通信之UPNP操作类的实现

主要依托于COM互操作来实现

添加COM引用 使用UPNP 1.0类型库 npnp.dll

主要对UPNP操作做了一个封装

1.自定义类型支持

 

public enum ProtocolType
{
    UDP,
    TCP
}

/// <summary>
/// 端口映射信息
/// </summary>
public class PortMappingInfo
{
    public string InternalIP;
    public int ExternalPort;
    public int InternalPort;
    public ProtocolType type;
    public string Description;
    public PortMappingInfo(string internalIP, int externalPort, int internalPort, ProtocolType type, string description)
    {
        this.InternalIP = internalIP;
        this.ExternalPort = externalPort;
        this.InternalPort = internalPort;
        this.type = type;
        this.Description = description;
    }
}

 

2.UPnP类实现

 

using System;
using System.Collections.Generic;
using System.Collections;
using System.Text;
using System.Net;
using System.Xml;
using System.IO;
using System.Net.Sockets;
using NATUPNPLib;

namespace Network
{
    public sealed class UPnPNat
    {
        private UPnPNATClass _uPnPNAT;
        
        public UPnPNat()
        {
            try
            {
                UPnPNATClass nat = new UPnPNATClass();
                //if (nat.NATEventManager != null && nat.StaticPortMappingCollection != null)
                    _uPnPNAT = nat;
            }
            catch{}

            if(_uPnPNAT==null)
                throw new NotSupportedException("没有可配置的UPNP NAT活动");
        }
        /// <summary>
        /// 增加端口映射
        /// </summary>
        /// <param name="ExternalPort">外部端口（路由器 NAT设备打开的端口）</param>
        /// <param name="InternalPort">内部端口 本机的端口</param>
        /// <param name="type">协议类型 UDP或TCP</param>
        /// <param name="InternalClient">内网IP地址或主机名</param>
        /// <param name="enable">是否启用</param>
        /// <param name="description">描述信息</param>
        public void AddStaticPortMapping(int ExternalPort,int InternalPort,ProtocolType type,string InternalClient,bool enable,string description)
        {
            _uPnPNAT.StaticPortMappingCollection.Add(ExternalPort, type.ToString().ToUpper(), InternalPort, InternalClient, enable, description);
        }
        /// <summary>
        /// 移除端口映射
        /// </summary>
        /// <param name="ExternalPort">外部端口号</param>
        /// <param name="type">协议类型</param>
        public void RemoveStaticPortMapping(int ExternalPort,ProtocolType type)
        {
            _uPnPNAT.StaticPortMappingCollection.Remove(ExternalPort, type.ToString().ToUpper());
        }
        public UPnPNATClass UPnPNAT
        {
            get { return _uPnPNAT; }
        }

        /// <summary>
        /// 获取端口映射信息
        /// </summary>
        public PortMappingInfo[] PortMappingsInfos
        {
            get
            {
                System.Collections.ArrayList portMappings = new ArrayList();
                int count = _uPnPNAT.StaticPortMappingCollection.Count;
                IEnumerator enumerator = _uPnPNAT.StaticPortMappingCollection.GetEnumerator();
                enumerator.Reset();
                for (int i = 0; i < count; i++)
                {
                    IStaticPortMapping mapping = null;
                    try
                    {
                        if(enumerator.MoveNext())
                            mapping=(IStaticPortMapping)enumerator.Current;
                    }
                    catch { }
                    if (mapping != null)
                        portMappings.Add(new PortMappingInfo(mapping.InternalClient, mapping.ExternalPort, mapping.InternalPort, mapping.Protocol == "TCP" ? ProtocolType.TCP : ProtocolType.UDP, mapping.Description));
                }
                PortMappingInfo[] portMappingInfos = new PortMappingInfo[portMappings.Count];
                portMappings.CopyTo(portMappingInfos);
                return portMappingInfos;
            }
        }
        
    }

    
}

 

使用NAT设备（路由器）的端口映射功能是实现P2P的一种重要方式 在UPNP开启的情况下把一台内网计算机直接暴露到公网上