基于DES的UDP通讯加密C程序

//--------------------------------------------------------------------// // 作者：刘文涛 // // 书籍：《网络安全编程技术与实例》 // //--------------------------------------------------------------------// #include <winsock2.h> #include <stdio.h> #include"des.h" #pragma comment( lib, "ws2_32.lib" ) #define BUFFERSIZE 1024 void main() { CDesOperate cDes; char strDecryBuffer[BUFFERSIZE]; int nLen=BUFFERSIZE; char *pKey="123456"; WSADATA wsaData; SOCKET ServerSocket; SOCKADDR_IN ServerAddr; SOCKADDR_IN ClientAddr; int ServerPort =52543; char ReceiveBuffer[1024]; int ClientAddrSize = sizeof(ClientAddr); int Result; if ((Result = WSAStartup(MAKEWORD(2, 2), &wsaData)) != 0) { printf("WSAStartup failed with error %d\n", Result); return ; } ServerSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); if (ServerSocket < 0) { printf("socket failed with error %d\n", WSAGetLastError()); return ; } ServerAddr.sin_family = AF_INET; ServerAddr.sin_port = htons(ServerPort); ServerAddr.sin_addr.s_addr = htonl(INADDR_ANY); Result = bind(ServerSocket, (SOCKADDR*) &ServerAddr, sizeof(ServerAddr)); if (Result < 0) { printf("bind failed with error %d\n", WSAGetLastError()); return ; } int len; //printf("Received 解密Data:%s From :%s\n", strDecryBuffer,inet_ntoa(ClientAddr.sin_addr)); while (1) { memset(ReceiveBuffer, 0, sizeof(ReceiveBuffer)); memset(&ClientAddr, 0, sizeof(ClientAddr)); //cDes.Decry(ReceiveBuffer,BUFFERSIZE,strDecryBuffer,nLen,pKey,8);// if (len = recvfrom(ServerSocket, ReceiveBuffer, 1024, 0, (SOCKADDR*) &ClientAddr, &ClientAddrSize) < 0) { printf("recvfrom failed with error %d\n", WSAGetLastError()); return ; } else { printf("Received Data:%s From :%s\n", ReceiveBuffer, inet_ntoa(ClientAddr.sin_addr));//收到的加密数据 cDes.Decry(ReceiveBuffer,BUFFERSIZE,strDecryBuffer,nLen,pKey,8);//用于解密收到的的加密数据 printf("Received 解密Data:%s From :%s\n", strDecryBuffer,inet_ntoa(ClientAddr.sin_addr));//经过解密得出的原始数据 len = sendto(ServerSocket, ReceiveBuffer, strlen(ReceiveBuffer), 0, (SOCKADDR*) &ClientAddr, sizeof(ClientAddr)); if (len < 0) { printf("sendto failed with error %d\n", WSAGetLastError()); return ; } else { printf("Send the data:%s\n", ReceiveBuffer); } } } if (closesocket(ServerSocket) == SOCKET_ERROR) { printf("closesocket failed with error %d\n", WSAGetLastError()); } if (WSACleanup() == SOCKET_ERROR) { printf("WSACleanup failed with error %d\n", WSAGetLastError()); } }