p2pclient.c

很好用的udp穿透nat的程序代码,是两个在nat后的pc可以直接通讯。

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pthread.h>
#include "proto.h"
#include "Exception.h"
#include <iostream>

UserList ClientList;
 
#define COMMANDMAXC 256
#define MAXRETRY    5
int  PrimaryUDP;
char UserName[10];
char ServerIP[20];
bool RecvedACK;
int  mksock(int type)
{
	int  sock ;

 	sock = socket(AF_INET, type, 0);
 	if (sock < 0)
 	{
        	printf("create socket error");
  		throw Exception("");
 	}
	return sock;
}
stUserListNode GetUser(char *username)
{
	for(UserList::iterator UserIterator=ClientList.begin();
      		UserIterator!=ClientList.end();
       		++UserIterator)
 	{
  		if( strcmp( ((*UserIterator)->userName), username) == 0 )
   		return *(*UserIterator);
 	}
 	throw Exception("not find this user");
}
void BindSock(int  sock)
{
	sockaddr_in sin;
 	sin.sin_addr.s_addr = INADDR_ANY;
 	sin.sin_family = AF_INET;
 	sin.sin_port = 0;
 
 	if (bind(sock, (struct sockaddr*)&sin, sizeof(sin)) < 0)
  		throw Exception("bind error");
}
void ConnectToServer(int  sock,char *username, char *serverip)
{
	sockaddr_in remote;
 	stMessage sendbuf;
 	int usercount;
 	size_t fromlen;
 	int iread;
  	stUserListNode *node ;
  	in_addr tmp;

 	remote.sin_addr.s_addr = inet_addr(serverip);
	remote.sin_family = AF_INET;
 	remote.sin_port = htons(SERVER_PORT);
 	sendbuf.iMessageType = LOGIN;
 	strncpy(sendbuf.message.loginmember.userName, username, 10);
 	sendto(sock, (const char*)&sendbuf, sizeof(sendbuf), 0, (const sockaddr*)&remote,sizeof(remote));
 	fromlen = sizeof(remote);
 	iread = recvfrom(sock, (char *)&usercount, sizeof(int), 0, (sockaddr *)&remote, &fromlen);
 	if(iread<=0)
 	{
  		throw Exception("Login error\n");
 	}
 	cout<<"Have "<<usercount<<" users logined server:"<<endl;
 	for(int i = 0;i<usercount;i++)
 	{
  		node = new stUserListNode;
  		recvfrom(sock, (char*)node, sizeof(stUserListNode), 0, (sockaddr *)&remote, &fromlen);
  		ClientList.push_back(node);
  		cout<<"Username:"<<node->userName<<endl;
  		tmp.s_addr = htonl(node->ip);
  		cout<<"UserIP:"<<inet_ntoa(tmp)<<endl;
  		cout<<"UserPort:"<<node->port<<endl;
  		cout<<""<<endl;
 	}
}

void OutputUsage()
{
 	cout<<"You can input you command:\n"
  	<<"Command Type:\"send\",\"exit\",\"getu\"\n"
  	<<"Example : send Username Message\n"
  	<<"          exit\n"
  	<<"          getu\n"
  	<<endl;
}

bool SendMessageTo(char *UserName, char *Message)
{
 	char realmessage[256];
 	unsigned int UserIP;
 	unsigned short UserPort;
 	bool FindUser = false;
  	sockaddr_in remote;
  	stP2PMessage MessageHead;
  	stMessage transMessage;
  	int isend;
  	sockaddr_in server;

 	for(UserList::iterator UserIterator=ClientList.begin();
      		UserIterator!=ClientList.end();
      		++UserIterator)
 	{
  		if( strcmp( ((*UserIterator)->userName), UserName) == 0 )
  		{
   			UserIP = (*UserIterator)->ip;
   			UserPort = (*UserIterator)->port;
   			FindUser = true;
  		}
 	}
 	if(!FindUser)
  		return false;
 	strcpy(realmessage, Message);
	for(int i=0;i<MAXRETRY;i++)
 	{
  		RecvedACK = false;
  		remote.sin_addr.s_addr = htonl(UserIP);
  		remote.sin_family = AF_INET;
  		remote.sin_port = htons(UserPort);
  		MessageHead.iMessageType = P2PMESSAGE;
  		MessageHead.iStringLen = (int)strlen(realmessage)+1;
  		isend = sendto(PrimaryUDP, (const char *)&MessageHead, sizeof(MessageHead), 0, (const sockaddr*)&remote, sizeof(remote));
  		isend = sendto(PrimaryUDP, (const char *)&realmessage, MessageHead.iStringLen, 0, (const sockaddr*)&remote, sizeof(remote));
  		for(int j=0;j<10;j++)
  		{
   			if(RecvedACK)
    				return true;
   			else
    				usleep(300);
  		}
  		server.sin_addr.s_addr = inet_addr(ServerIP);
  		server.sin_family = AF_INET;
  		server.sin_port = htons(SERVER_PORT);
  		transMessage.iMessageType = P2PTRANS;
  		strcpy(transMessage.message.translatemessage.userName, UserName);
  		sendto(PrimaryUDP, (const char*)&transMessage, sizeof(transMessage), 0, (const sockaddr*)&server, sizeof(server));
  		usleep(100);
 	}
 	return false;
}

void ParseCommand(char * CommandLine)
{
 	char Command[10];
  	stMessage sendbuf;
  	sockaddr_in server;
  	char sendname[20];
  	char message[COMMANDMAXC];
  	int command;
  	int i;

 	if(strlen(CommandLine)<4)
  		return;
 	strncpy(Command, CommandLine, 4);
 	Command[4]='\0';
 	if(strcmp(Command,"exit")==0)
 	{
  		sendbuf.iMessageType = LOGOUT;
  		strncpy(sendbuf.message.logoutmember.userName, UserName, 10);
  		server.sin_addr.s_addr = inet_addr(ServerIP);
  		server.sin_family = AF_INET;
  		server.sin_port = htons(SERVER_PORT);
  		sendto(PrimaryUDP,(const char*)&sendbuf, sizeof(sendbuf), 0, (const sockaddr *)&server, sizeof(server));
  		shutdown(PrimaryUDP, 2);
  		close(PrimaryUDP);
  		exit(0);
 	}
 	else if(strcmp(Command,"send")==0)
 	{
  		for(i=5;;i++)
  		{
   			if(CommandLine[i]!=' ')
    				sendname[i-5]=CommandLine[i];
   			else
   			{
    				sendname[i-5]='\0';
    				break;
   			}
  		}
  		strcpy(message, &(CommandLine[i+1]));
printf("send name and messages is %s,%s\n",sendname,message);
  		if(SendMessageTo(sendname, message))
   			printf("Send OK!\n");
  		else 
   			printf("Send Failure!\n");
 	}
 	else if(strcmp(Command,"getu")==0)
 	{
  		command = GETALLUSER;
  		server.sin_addr.s_addr = inet_addr(ServerIP);
  		server.sin_family = AF_INET;
  		server.sin_port = htons(SERVER_PORT);
  		sendto(PrimaryUDP,(const char*)&command, sizeof(command), 0, (const sockaddr *)&server, sizeof(server));
 	}
}

void * RecvThreadProc(void * lpParameter)
{
 	sockaddr_in remote;
 	stP2PMessage recvbuf;
     	stP2PMessage sendbuf;
    	char *comemessage;
    	stP2PMessage message;
    	int usercount;
  	int iread;
    	size_t fromlen;
    	int iread1;
     	in_addr tmp;
 	size_t sinlen = sizeof(remote);
 	for(;;)
 	{
  		iread = recvfrom(PrimaryUDP, (char *)&recvbuf, sizeof(recvbuf), 0, (sockaddr *)&remote, &sinlen);
  		if(iread<=0)
  		{
   			printf("recv error\n");
   			continue;
  		}
  		switch(recvbuf.iMessageType)
  		{
  			case P2PMESSAGE:
   			{
    				comemessage= new char[recvbuf.iStringLen];
    				iread1 = recvfrom(PrimaryUDP, comemessage, 256, 0, (sockaddr *)&remote, &sinlen);
    				comemessage[iread1-1] = '\0';
    				if(iread1<=0)
     					throw Exception("Recv Message Error\n");
    				else
    				{
     					printf("Recv a Message:%s\n",comemessage);
     
     					sendbuf.iMessageType = P2PMESSAGEACK;
     					sendto(PrimaryUDP, (const char*)&sendbuf, sizeof(sendbuf), 0, (const sockaddr*)&remote, sizeof(remote));
    				}
    				delete []comemessage;
    				break;
   			}
  			case P2PSOMEONEWANTTOCALLYOU:
   			{
    				printf("Recv p2someonewanttocallyou data\n");
    				remote.sin_addr.s_addr = htonl(recvbuf.iStringLen);
    				remote.sin_family = AF_INET;
    				remote.sin_port = htons(recvbuf.Port);
    				message.iMessageType = P2PTRASH;
    				sendto(PrimaryUDP, (const char *)&message, sizeof(message), 0, (const sockaddr*)&remote, sizeof(remote));
                
    				break;
   			}
  			case P2PMESSAGEACK:
   			{
    				RecvedACK = true;
    				break;
   			}
  			case P2PTRASH:
   			{
    				printf("Recv p2ptrash data\n");
    				break;
   			}
  			case GETALLUSER:
   			{
    				fromlen = sizeof(remote);
    				iread = recvfrom(PrimaryUDP, (char *)&usercount, sizeof(int), 0, (sockaddr *)&remote, &fromlen);
    				if(iread<=0)
    				{
     					throw Exception("Login error\n");
    				}
    				ClientList.clear();
    				cout<<"Have "<<usercount<<" users logined server:"<<endl;
    				for(int i = 0;i<usercount;i++)
    				{
     					stUserListNode *node = new stUserListNode;
     					recvfrom(PrimaryUDP, (char*)node, sizeof(stUserListNode), 0, (sockaddr *)&remote, &fromlen);
     					ClientList.push_back(node);
     					cout<<"Username:"<<node->userName<<endl;
     					tmp.s_addr = htonl(node->ip);
     					cout<<"UserIP:"<<inet_ntoa(tmp)<<endl;
     					cout<<"UserPort:"<<node->port<<endl;
     					cout<<""<<endl;
    				}
    				break;
   			}
  		}
 	}
}

int main(int argc, char* argv[])
{
  	pthread_t threadhandle ;
   	char Command[COMMANDMAXC];
 	try
 	{
  		PrimaryUDP = mksock(SOCK_DGRAM);
  		BindSock(PrimaryUDP);
  		cout<<"Please input server ip:";
  		cin>>ServerIP;
  		cout<<"Please input your name:";
  		cin>>UserName;
  		ConnectToServer(PrimaryUDP, UserName, ServerIP);
  		pthread_create(&threadhandle, 0, RecvThreadProc, NULL);
  		//CloseHandle(threadhandle);
  		OutputUsage();
  		for(;;)
  		{
   			gets(Command);
   			ParseCommand(Command);
  		}
 	}
 	catch(Exception &e)
 	{
  		printf(e.GetMessage());
  		return 1;
 	}
 	return 0;
}