java通过ssh反向隧道访问客户端的摄像头

首先确保服务器已经安装JSch，这是一个可以使用Java实现SSH连接的类库。客户端已经安装了expect组件。

接下来需要实现以下几个步骤：

1. 通过Sshconnect.sh脚本启动客户端的SSH服务（如果还没有启动）

2. 使用JSch库建立反向隧道连接到客户端的SSH服务

3. 调用客户端资源，比如摄像头

下面是代码示例：

import com.jcraft.jsch.*;

public class SshReverseTunnel {
    public static void main(String[] args) {
        String host = "client_host"; // 客户端主机名或 IP
        int port = 22; // 客户端 SSH 服务端口号
        String user = "client_user"; // 客户端 SSH 用户名
        String password = "******"; // 客户端 SSH 密码

        try {
            // 启动客户端的 SSH 服务
            Runtime.getRuntime().exec("/path/to/Sshconnect.sh"); 

            JSch jsch = new JSch();
            Session session = jsch.getSession(user, host, port);
            session.setPassword(password);

            // 设置配置项
            java.util.Properties config = new java.util.Properties();
            config.put("StrictHostKeyChecking", "no");
            config.put("Compression", "yes");
            config.put("ConnectionAttempts", "2");

            session.setConfig(config);
            session.connect();

            // 建立反向隧道
            int tunnelPort = 12345; // 当前服务器上监听的端口号
            int remotePort = 22; // 客户端上用于监听的端口号
            String remoteServer = "localhost"; // 客户端上监听地址，本例是客户端本地
            session.setPortForwardingR(tunnelPort, remoteServer, remotePort);

            // 调用客户端资源，比如摄像头

            // 断开连接
            session.disconnect();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

客户端要定时去检查这个端口和服务是否启动。代码如下：

/**
     * 定时获取ssh通道端口，并建立、关闭 连接
     */
    @Override
    public void checkSport() throws Exception {
        if (Constant.isEntered) {
            FsmsRsp<SshQryRspVo> resp = RemoteServerUtil.form(ssh_url + "/" + Constant.localInfoBus.getBusId(), new HashMap(), new FsmsRsp<SshQryRspVo>() {
            }.getClass());

            SshQryRspVo sshQryRspVo = resp.getData();
            int sport = sshQryRspVo.getSport();

            if (sport == 0) {
                log.info("从服务器取得信息，将关闭本端口"+sshQryRspVo.getIp()+"/"+sshQryRspVo.getPort());
                Constant.sshSport = 0;
                //关闭ssh
                Process ps = Runtime.getRuntime().exec(localShellSshScript + " close x x x x x");
                ps.waitFor();
            } else {
                log.info("从服务器取得信息，将创建SSH通道");
                Constant.sshSport = sport;
                String ip = sshQryRspVo.getIp();
                int port = sshQryRspVo.getPort();
                String username = sshQryRspVo.getUsername();
                String passwrod = sshQryRspVo.getPassword();
                log.info("创建SSH通道命令如下:\r\n"+localShellSshScript + " open " + ip + " " + port + " " + username + " " + passwrod + " " + sport);
                //打开ssh
                Process ps = Runtime.getRuntime().exec(localShellSshScript + " open " + ip + " " + port + " " + username + " " + passwrod + " " + sport);

                ps.waitFor();
            }
        }
    }

其中执行的脚本.sh是这样的，上文当中的变量localShellSshScript=sshconnect.sh，放在根目录下。

#!/bin/bash
flag="$1"
ip="$2"
port="$3"
username="$4"
password="$5"
sport="$6"

#echo ${flag} >> /data/ec/scripts/xxx.log
#echo ${ip} >> /data/ec/scripts/xxx.log
#echo ${port} >> /data/ec/scripts/xxx.log
#echo ${username} >> /data/ec/scripts/xxx.log
#echo ${password} >> /data/ec/scripts/xxx.log
#echo ${sport} >> /data/ec/scripts/xxx.log

if [ "${flag}" = "open" ]; then
  #echo '11111111111111111111'  >> /data/ec/scripts/xxx.log
  count=`ps -aux | grep ':localhost:7001' | grep -v grep | wc -l`
  if [ "${count}" -eq "0" ];then
    
    #echo '222222222222' >> /data/ec/scripts/xxx.log
        /usr/bin/expect << EOF
        set time 30
        spawn ssh -p ${port} -fCNR ${sport}:localhost:7001 ${username}@${ip}
        expect {
            "*yes/no*" {send "yes\r"; exp_continue }
            "*password:" { send "${password}\r" }
        }
        expect eof
EOF
  fi
elif [ "${flag}" = "close" ]; then
    #echo '333333333333' >> /data/ec/scripts/xxx.log
    kill -9 `ps -aux | grep ':localhost:7001' | grep -v grep | awk '{print $2}'`
fi 

#echo '444444444444' >> /data/ec/scripts/xxx.log