步骤四:(可选)修改源站业务代码,同时获取 IPv4/IPv6 客户端真实 IP

最近更新时间:2024-09-13 14:55:51

我的收藏
说明:
本章节操作仅在源站需同时获取 IPv4 和 IPv6 客户端地址信息时参考,该操作将指引您如何修改源站业务代码。
源站在建立服务监听时,可参考采用如下两种方式:
1. 采用 IPv4 的地址结构(struct sockaddr_in)搭建服务,其监听的是 IPv4 格式的地址。
2. 采用 IPv6 的地址结构(struct sockaddr_in6)搭建服务,其监听的是 IPv6 格式的地址。

示例代码

监听 IPv4 地址
监听 IPv6 地址
C
Java
#include <sys/socket.h>
#include <stdio.h>
#include <unistd.h>
#include <netinet/in.h>
#include <memory.h>
#include <arpa/inet.h>

int main(int argc, char **argv){
int l_sockfd;
// 服务器地址采用v4结构
struct sockaddr_in serveraddr;
// 业务修改点: 客户端地址必须采用v6结构
struct sockaddr_in6 clientAddr;
int server_port = 10000;

memset(&serveraddr, 0, sizeof(serveraddr));
// 创建socket
l_sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (l_sockfd == -1){
printf("Failed to create socket.\\n");
return -1;
}
// 初始化服务器地址信息
memset(&serveraddr, 0, sizeof(struct sockaddr_in));
serveraddr.sin_family = AF_INET;
serveraddr.sin_port = htons(server_port);
serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);

int isReuse = 1;
setsockopt(l_sockfd, SOL_SOCKET,SO_REUSEADDR,(const char*)&isReuse,sizeof(isReuse));
// 关联socket和服务器地址信息
int nRet = bind(l_sockfd,(struct sockaddr*)&serveraddr, sizeof(serveraddr));
if(-1 == nRet)
{
printf("bind error\\n");
return -1;
}
// 监听socket
listen(l_sockfd, 5);

int clientAddrLen = sizeof(clientAddr);
memset(&clientAddr, 0, sizeof(clientAddr));
// 接受来自客户端的连接
int linkFd = accept(l_sockfd, (struct sockaddr*)&clientAddr, &clientAddrLen);
if(-1 == linkFd)
{
printf("accept error\\n");
return -1;
}
// 业务修改点: 根据客户端sin6_family的类型, 判断客户端是v4地址还是v6地址
// 当为AF_INET时, 表示客户端是IPv4, 将客户端地址指针转换为struct sockaddr_in*进行获取
// 当为AF_INET6时, 表示客户端是IPv6, 使用struct sockaddr_in6*进行获取
if (clientAddr.sin6_family == AF_INET) {
printf("AF_INET accept getpeername %s : %d successful\\n",
inet_ntoa(((struct sockaddr_in*)&clientAddr)->sin_addr),
ntohs(((struct sockaddr_in*)&clientAddr)->sin_port));
}else if (clientAddr.sin6_family == AF_INET6){
char addr_p[128] = {0};
inet_ntop(AF_INET6, (void *)&((struct sockaddr_in6*)&clientAddr)->sin6_addr, addr_p, (socklen_t )sizeof(addr_p));
printf("AF_INET6 accept getpeername %s : %d successful\\n",
addr_p,
ntohs(((struct sockaddr_in6*)&clientAddr)->sin6_port));
}else{
printf("unknow sin_family:%d \\n", clientAddr.sin6_family);
}
close(l_sockfd);
return 0;
}
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;


public class ServerDemo {


/** 若采用 IPv4 的地址结构搭建服务,使用 IPV4_HOST */
public static final String IPV4_HOST = "0.0.0.0";


/** 若采用 IPv6 的地址结构搭建服务,使用 IPV6_HOST */
public static final String IPV6_HOST = "::";


public static void main(String[] args) {
int serverPort = 10000;
try (ServerSocket serverSocket = new ServerSocket()) {
// 设置地址复用
serverSocket.setReuseAddress(true);
// 绑定服务器地址和端口,这里使用 IPv4
serverSocket.bind(new InetSocketAddress(InetAddress.getByName(IPV4_HOST), serverPort));
System.out.println("Server is listening on port " + serverPort);


while (true) {
// 接受客户端连接
Socket clientSocket = serverSocket.accept();
System.out.println("New client connected: " + clientSocket.getRemoteSocketAddress());


// 处理客户端请求
handleClientRequest(clientSocket);
}
} catch (IOException e) {
System.err.println("Failed to create server socket: " + e.getMessage());
}
}


/**
* 处理函数,具体业务具体实现,这里只做为示例
* 此函数的作用是将 client 的输入原封不动的返回给 client
*/
private static void handleClientRequest(Socket clientSocket) {
try (InputStream inputStream = clientSocket.getInputStream();
OutputStream outputStream = clientSocket.getOutputStream()) {


// 读取客户端发来的数据
byte[] buffer = new byte[1024];
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) != -1) {
// 将接收到的数据原样回复给客户端
outputStream.write(buffer, 0, bytesRead);
}


} catch (IOException e) {
// 当客户端断开连接后
System.err.println("Failed to handle client request: " + e.getMessage());
} finally {
try {
clientSocket.close();
} catch (IOException e) {
System.err.println("Failed to close client socket: " + e.getMessage());
}
}
}
}
C
Java
#include <sys/socket.h>
#include <stdio.h>
#include <unistd.h>
#include <netinet/in.h>
#include <memory.h>
#include <arpa/inet.h>

int main(int argc, char **argv){
int l_sockfd;
// 服务器地址采用v6结构
struct sockaddr_in6 serveraddr;
// 客户端地址采用v6结构
struct sockaddr_in6 clientAddr;
int server_port = 10000;

memset(&serveraddr, 0, sizeof(serveraddr));
// 创建socket
l_sockfd = socket(AF_INET6, SOCK_STREAM, 0);
if (l_sockfd == -1){
printf("Failed to create socket.\\n");
return -1;
}
// 设置服务器地址信息
memset(&serveraddr, 0, sizeof(struct sockaddr_in6));
serveraddr.sin6_family = AF_INET6;
serveraddr.sin6_port = htons(server_port);
serveraddr.sin6_addr = in6addr_any;

int isReuse = 1;
setsockopt(l_sockfd, SOL_SOCKET,SO_REUSEADDR,(const char*)&isReuse,sizeof(isReuse));
// 关联socket和服务器地址信息
int nRet = bind(l_sockfd,(struct sockaddr*)&serveraddr, sizeof(serveraddr));
if(-1 == nRet)
{
printf("bind error\\n");
return -1;
}
// 监听socket
listen(l_sockfd, 5);

int clientAddrLen = sizeof(clientAddr);
memset(&clientAddr, 0, sizeof(clientAddr));
// 接受来自客户端的连接请求
int linkFd = accept(l_sockfd, (struct sockaddr*)&clientAddr, &clientAddrLen);
if(-1 == linkFd)
{
printf("accept error\\n");
return -1;
}
// 这里收到的客户端地址信息全部都采用v6的结构进行存储
// 其中,客户端的IPv4地址也被映射成了一个IPv6的地址,例如:::ffff:119.29.1.1
char addr_p[128] = {0};
inet_ntop(AF_INET6, (void *)&clientAddr.sin6_addr, addr_p, (socklen_t )sizeof(addr_p));
printf("accept %s : %d successful\\n", addr_p, ntohs(clientAddr.sin6_port));
// 业务修改点:通过系统宏定义IN6_IS_ADDR_V4MAPPED来判断一个IPv6地址是否是IPv4的映射地址(代表客户端是IPv4)
if(IN6_IS_ADDR_V4MAPPED(&clientAddr.sin6_addr)) {
struct sockaddr_in real_v4_sin;
memset (&real_v4_sin, 0, sizeof (struct sockaddr_in));
real_v4_sin.sin_family = AF_INET;
real_v4_sin.sin_port = clientAddr.sin6_port;
// 读取最后四个字节即为客户端真实IPv4地址
memcpy (&real_v4_sin.sin_addr, ((char *)&clientAddr.sin6_addr) + 12, 4);
printf("connect %s successful\\n", inet_ntoa(real_v4_sin.sin_addr));
}
close(l_sockfd);
return 0;
}
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;

public class ServerDemo {

/** 若采用 IPv4 的地址结构搭建服务,使用 IPV4_HOST */
public static final String IPV4_HOST = "0.0.0.0";

/** 若采用 IPv6 的地址结构搭建服务,使用 IPV6_HOST */
public static final String IPV6_HOST = "::";

public static void main(String[] args) {
int serverPort = 10000;
try (ServerSocket serverSocket = new ServerSocket()) {
// 设置地址复用
serverSocket.setReuseAddress(true);
// 绑定服务器地址和端口,这里使用 IPv4
serverSocket.bind(new InetSocketAddress(InetAddress.getByName(IPV6_HOST), serverPort));
System.out.println("Server is listening on port " + serverPort);

while (true) {
// 接受客户端连接
Socket clientSocket = serverSocket.accept();
System.out.println("New client connected: " + clientSocket.getRemoteSocketAddress());

// 处理客户端请求
handleClientRequest(clientSocket);
}
} catch (IOException e) {
System.err.println("Failed to create server socket: " + e.getMessage());
}
}

/**
* 处理函数,具体业务具体实现,这里只做为示例
* 此函数的作用是将 client 的输入原封不动的返回给 client
*/
private static void handleClientRequest(Socket clientSocket) {
try (InputStream inputStream = clientSocket.getInputStream();
OutputStream outputStream = clientSocket.getOutputStream()) {

// 读取客户端发来的数据
byte[] buffer = new byte[1024];
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) != -1) {
// 将接收到的数据原样回复给客户端
outputStream.write(buffer, 0, bytesRead);
}

} catch (IOException e) {
// 当客户端断开连接后
System.err.println("Failed to handle client request: " + e.getMessage());
} finally {
try {
clientSocket.close();
} catch (IOException e) {
System.err.println("Failed to close client socket: " + e.getMessage());
}
}
}
}

控制台输出结果

Server is listening on port 10000
New client connected: /127.0.0.1:50680
New client connected: /0:0:0:0:0:0:0:1:51124
New client connected: /127.0.0.1:51136