C语言网络验证客户端服务端代码（Windows Mingw）

以下是一个简单的网络验证客户端和服务端的代码示例：

客户端代码（client.c）：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <winsock2.h>

#define MAX_BUFFER_SIZE 1024

int main() {
    WSADATA wsaData;
    SOCKET clientSocket;
    struct sockaddr_in serverAddr;
    char serverIP[15] = '127.0.0.1';
    int serverPort = 8888;
    char buffer[MAX_BUFFER_SIZE];
    char machineCode[100];
    char username[100];
    char password[100];

    // 初始化Winsock
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
        printf('Failed to initialize winsock.\n');
        return 1;
    }

    // 创建客户端套接字
    clientSocket = socket(AF_INET, SOCK_STREAM, 0);
    if (clientSocket == INVALID_SOCKET) {
        printf('Failed to create client socket.\n');
        WSACleanup();
        return 1;
    }

    // 设置服务器地址
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(serverPort);
    serverAddr.sin_addr.s_addr = inet_addr(serverIP);

    // 连接到服务器
    if (connect(clientSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR) {
        printf('Failed to connect to server.\n');
        closesocket(clientSocket);
        WSACleanup();
        return 1;
    }

    // 从用户输入获取机器码、用户名和密码
    printf('Enter machine code: ');
    fgets(machineCode, sizeof(machineCode), stdin);
    machineCode[strcspn(machineCode, '\n')] = '\0';
    
    printf('Enter username: ');
    fgets(username, sizeof(username), stdin);
    username[strcspn(username, '\n')] = '\0';
    
    printf('Enter password: ');
    fgets(password, sizeof(password), stdin);
    password[strcspn(password, '\n')] = '\0';

    // 发送验证请求给服务器
    sprintf(buffer, '%s,%s,%s', machineCode, username, password);
    send(clientSocket, buffer, strlen(buffer), 0);

    // 接收服务器的验证结果
    memset(buffer, 0, sizeof(buffer));
    recv(clientSocket, buffer, sizeof(buffer) - 1, 0);

    printf('Server response: %s\n', buffer);

    // 关闭套接字和清理Winsock
    closesocket(clientSocket);
    WSACleanup();

    return 0;
}

服务端代码（server.c）：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <winsock2.h>
#include <windows.h>

#define MAX_BUFFER_SIZE 1024
#define MAX_CLIENTS 100

typedef struct {
    SOCKET socket;
    char machineCode[100];
    char username[100];
    char password[100];
} Client;

Client clients[MAX_CLIENTS];
int numClients = 0;

DWORD WINAPI ClientHandler(LPVOID clientSocket);

int main() {
    WSADATA wsaData;
    SOCKET serverSocket, clientSocket;
    struct sockaddr_in serverAddr, clientAddr;
    int serverPort = 8888;
    int clientAddrLen;
    HANDLE threadHandle;

    // 初始化Winsock
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
        printf('Failed to initialize winsock.\n');
        return 1;
    }

    // 创建服务器套接字
    serverSocket = socket(AF_INET, SOCK_STREAM, 0);
    if (serverSocket == INVALID_SOCKET) {
        printf('Failed to create server socket.\n');
        WSACleanup();
        return 1;
    }

    // 设置服务器地址
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(serverPort);
    serverAddr.sin_addr.s_addr = INADDR_ANY;

    // 绑定服务器地址
    if (bind(serverSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR) {
        printf('Failed to bind server address.\n');
        closesocket(serverSocket);
        WSACleanup();
        return 1;
    }

    // 监听连接请求
    if (listen(serverSocket, MAX_CLIENTS) == SOCKET_ERROR) {
        printf('Failed to listen for connections.\n');
        closesocket(serverSocket);
        WSACleanup();
        return 1;
    }

    printf('Server started. Waiting for connections...\n');

    while (1) {
        // 接受客户端连接
        clientAddrLen = sizeof(clientAddr);
        clientSocket = accept(serverSocket, (struct sockaddr*)&clientAddr, &clientAddrLen);
        if (clientSocket == INVALID_SOCKET) {
            printf('Failed to accept client connection.\n');
            closesocket(serverSocket);
            WSACleanup();
            return 1;
        }

        printf('Client connected: %s\n', inet_ntoa(clientAddr.sin_addr));

        // 创建新线程处理客户端请求
        threadHandle = CreateThread(NULL, 0, ClientHandler, (LPVOID)clientSocket, 0, NULL);
        if (threadHandle == NULL) {
            printf('Failed to create client thread.\n');
            closesocket(clientSocket);
            closesocket(serverSocket);
            WSACleanup();
            return 1;
        }

        CloseHandle(threadHandle);
    }

    // 关闭服务器套接字和清理Winsock
    closesocket(serverSocket);
    WSACleanup();

    return 0;
}

DWORD WINAPI ClientHandler(LPVOID clientSocket) {
    SOCKET socket = (SOCKET)clientSocket;
    char buffer[MAX_BUFFER_SIZE];
    char machineCode[100];
    char username[100];
    char password[100];

    // 接收验证请求
    memset(buffer, 0, sizeof(buffer));
    recv(socket, buffer, sizeof(buffer) - 1, 0);

    printf('Received request: %s\n', buffer);

    // 解析机器码、用户名和密码
    sscanf(buffer, '%[^,],%[^,],%[^,]', machineCode, username, password);

    // 进行验证（这里只是简单示例，实际应用中需根据具体需求实现验证逻辑）
    int isValid = 0;
    for (int i = 0; i < numClients; i++) {
        if (strcmp(machineCode, clients[i].machineCode) == 0 &&
            strcmp(username, clients[i].username) == 0 &&
            strcmp(password, clients[i].password) == 0) {
            isValid = 1;
            break;
        }
    }

    // 发送验证结果给客户端
    if (isValid) {
        send(socket, 'Valid', strlen('Valid'), 0);
    } else {
        send(socket, 'Invalid', strlen('Invalid'), 0);
    }

    // 关闭客户端套接字
    closesocket(socket);

    return 0;
}

编译和运行：

使用Mingw编译客户端和服务端代码：

gcc -o client client.c -lws2_32 gcc -o server server.c -lws2_32

2. 运行服务端：

server.exe

3. 运行客户端：

client.exe

客户端将提示输入机器码、用户名和密码，然后发送验证请求给服务器，并接收服务器的验证结果。

注意：这只是一个简单的示例，实际应用中需要根据需求进行改进和完善，如存储用户信息的方式、验证逻辑的复杂性等。