[Programming] Giao tiếp đơn giản giữa client và server bằng WinSock

Author: T4mQu0c

Source đơn giản còn nhiều bug
Client:

Code:

#include 
#include 
#include 
#include 

#pragma comment(lib, "ws2_32.lib") 
#define BUFF_MAX 1024

BOOL ConnectServer(char *ip, unsigned int port)
{ 
 // Khai bao bien 
 WSADATA wsaData;
 SOCKADDR_IN connect_sockaddr;
 SOCKET connect_socket;

 printf("[+] Client ... \n"); 
 if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0)
 {
  printf("Failed: %d)\n", GetLastError());
  return FALSE;
 }

 connect_socket = WSASocket(AF_INET,SOCK_STREAM,IPPROTO_TCP,NULL,NULL,NULL);
 if (connect_socket == INVALID_SOCKET)
 {
  printf("Failed: %d)\n", GetLastError());
  WSACleanup();
  return FALSE;
 }

 // Set IP, port
 connect_sockaddr.sin_port = htons(port);
 connect_sockaddr.sin_family = AF_INET;
 connect_sockaddr.sin_addr.s_addr = inet_addr(ip);

 printf("[+] Connect to %s:%d...\n", ip, port);
 if (WSAConnect(connect_socket, (sockaddr*) &connect_sockaddr, sizeof(sockaddr), NULL, NULL, NULL, NULL) == SOCKET_ERROR)
 {
  printf("Failed: %d)\n", GetLastError());
  WSACleanup();
  return EXIT_FAILURE;
 }

 // Nhan ket qua tu server (dong Welcome tu Server)
 char buff[BUFF_MAX] = {0};
 recv(connect_socket, buff, BUFF_MAX, 0);
 printf("%s\n", buff);

 while(TRUE)
 {
  ZeroMemory(buff, sizeof(buff));
  printf("Enter command:");
  scanf("%s", &buff);
  if (stricmp(buff, "quit") == 0)  
   goto CleanUp;
  
  send(connect_socket, buff, strlen(buff), 0);
 }

CleanUp:
 closesocket(connect_socket);  
 WSACleanup();
 return TRUE;
}

int _tmain(int argc, char* argv[])
{
 if (argc != 3)
 {
  printf("Invalid parameter\n");  
  printf("%s  \n", argv[0]);
  return 0;
 }

 char ip[16] = {0};
 int port;
 strcpy(ip, argv[1]);
 port = atoi(argv[2]);

 // Kiem tra Port
 if (port <> 65535)
 {
  printf("Invalid Port\n");
  return 0;
 }
  
 ConnectServer(ip, port); 

 return 0;
}

Server:

Code:

#include 
#include 
#include 
#include 

#pragma comment(lib, "ws2_32.lib") 
#define BUFF_MAX 1024

BOOL ListenPort(unsigned int port)
{ 
 // Khai bao bien 
 WSADATA wsaData;
 SOCKET Winsock;   
 SOCKET ListenSock;  
 sockaddr_in Winsock_In;
 
 printf("[+] Server ... \n"); 
 if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0)
 {
  printf("Failed: %d)\n", GetLastError());
  return FALSE;
 }

 Winsock = WSASocket(AF_INET,SOCK_STREAM,IPPROTO_TCP,NULL,NULL,NULL);
 if (Winsock == INVALID_SOCKET)
 {
  printf("Failed: %d)\n", GetLastError());
  WSACleanup();
  return FALSE;
 }

 // Set IP, port
 Winsock_In.sin_family = AF_INET;
 Winsock_In.sin_port = htons(port);
 Winsock_In.sin_addr.s_addr = htonl(INADDR_ANY);

 // Bind Port
 if(bind(Winsock,(SOCKADDR*)&Winsock_In,sizeof(sockaddr_in)) == SOCKET_ERROR)
 {
  printf("Failed: %d)\n", GetLastError());
  WSACleanup();
  return FALSE;
 }

 // Listen Port
 printf("[+] Listen port: %d\n", port);
 if(listen(Winsock,5) == SOCKET_ERROR)
 {
  printf("Failed: %d)\n", GetLastError());
  WSACleanup();
  return FALSE;
 }
 
 printf("[+] Wait for Connect on port : %d\n", port);
 if((ListenSock=accept(Winsock,NULL,NULL))==INVALID_SOCKET)
 {
  printf("Failed: %d)\n", GetLastError());
  WSACleanup();
  return FALSE;
 }

 printf("[+] Client connectd\n");

 // Send welcome to Client
 char szWelcome[] = "Xin chao ban";
 send(ListenSock, szWelcome, strlen(szWelcome),0 );

 char buff[BUFF_MAX] = {0};
 while(TRUE)
 {
  ZeroMemory(buff, sizeof(buff));
  recv(ListenSock, buff, BUFF_MAX, 0);
  if (stricmp(buff, "bye") == 0)  // Thoat
   break;
  else
   system(buff); // Thuc hien lenh cua client tren Server
 }

CleanUp:
 
 closesocket(ListenSock);
 closesocket(Winsock);  
 WSACleanup();

 return TRUE;
}

int _tmain(int argc, _TCHAR* argv[])
{
 ListenPort(12345);
 return 0;
}

- Trước tiên chạy server trước để listen port 12345
- Sau đó chạy client với tham số
ví dụ:
Client 127.0.0.1 12345