java:执行linux sudo命令

╰+攻爆jí腚メ 2022-06-02 00:13 704阅读 0赞

我们知道java中执行控制台命令，都是通过 `Runtime.exec`系列方法。  
如果要执行root权限的命令需要用到sudo,需要输入sudo密码,这个也好解决,使用echo可以向sudo输入密码，同时sudo要加-S参数指定从标准输入读取密码，示例如下：

> echo ‘sudopassword’ | sudo -S cat /etc/profile

但是在java中通过 `Runtime.exec`方法执行上面的命令，还是会无效。错误提示可能是。

> sudo：抱歉，您必须拥有一个终端来执行 sudo  
> sudo: sorry, you must have a tty to run sudo  
> sudo：没有终端存在，且未指定 askpass 程序  
> sudo: no tty present and no askpass program specified

解决这个问题需要修改/etc/sudoers

# 给 sudoers 增加写权限
    sudo chmod +w /etc/sudoers
    # 编辑 sudoers
    vi /etc/sudoers

找到 `Defaults requiretty`改为`Defaults !requiretty`或者直接注释掉`#Defaults requiretty`  
找到`Defaults !visiblepw`改为`Defaults visiblepw`或者增一行 `Defaults visiblepw`  
如下图。  
![这里写图片描述][SouthEast]

修改后 `wq`保存，记得要`sudo chmod -w /etc/sudoers`删除写权限

为了简化sudo命令的执行，我封装一了个CmdExceuor类,允许执行多条命令。

> 代码仓库地址：  
> [https://gitee.com/l0km/common-java/blob/master/common-base/src/main/java/net/gdface/utils/CmdExecutor.java][https_gitee.com_l0km_common-java_blob_master_common-base_src_main_java_net_gdface_utils_CmdExecutor.java]

import java.io.IOException;
    import java.io.InputStream;
    import java.io.InputStreamReader;
    import java.io.LineNumberReader;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Collections;
    import java.util.List;
    import java.util.logging.Logger;
    
    /**
     * linux命令行执行器
     * @author guyadong
     *
     */
    public class CmdExecutor{
        
        private static final Logger logger = Logger.getLogger(CmdExecutor.class.getSimpleName());
        private static final String SUDO_CMD = "sudo";
        private static final String SHELL_NAME = "/bin/bash";
        private static final String SHELL_PARAM = "-c";
        private static final String REDIRECT = "2>&1";
        /** 执行 sudo 的密码 */
        private final String sudoPassword;
        /** 是否显示命令内容及输出 */
        private boolean verbose=true;
        /** 是否错误输出重定向 */
        private boolean errRedirect = true;
        /** 是否同步，主线程是否等待命令执行结束 */
        private boolean sync = true;
        /** 执行多条命令时的命令分隔符 */
        private String cmdSeparator = " && ";
        private List<String> cmds = new ArrayList<String>(16);
        public static CmdExecutor builder(){
            return new CmdExecutor();
        }
        public static CmdExecutor builder(String sudoPasword){
            return new CmdExecutor(sudoPasword);
        }
        protected CmdExecutor(){
            this(null);
        }
        protected CmdExecutor(String sudoPasword){
            this.sudoPassword = sudoPasword;
        }
        public CmdExecutor verbose(boolean verbose){
            this.verbose = verbose;
            return this;
        }
        public CmdExecutor errRedirect(boolean errRedirect){
            this.errRedirect = errRedirect;
            return this;
        }
        public CmdExecutor sync(boolean sync){
            this.sync = sync;
            return this;
        }
        public CmdExecutor cmdSeparator(String cmdSeparator){
            if(null != cmdSeparator && !cmdSeparator.isEmpty()){
                this.cmdSeparator = cmdSeparator;
            }
            return this;
        }
        private String getRedirect(){
            return errRedirect ? REDIRECT : "";
        }
        /**
         * 添加一条需要sudo执行的命令
         * @param cmd 要执行的命令(字符串中不需要有sudo)
         * @return
         */
        public CmdExecutor sudoCmd(String cmd){
            if(null != cmd && 0 != cmd.length()){
                if(null == sudoPassword){
                    cmds.add(String.format("%s %s %s",SUDO_CMD,cmd,getRedirect()));                 
                }else{
                    cmds.add(String.format("echo '%s' | %s %s %s",sudoPassword,SUDO_CMD,cmd,getRedirect()));
                }                   
            }
            return this;
        }
        /**
         * 添加一条普通命令
         * @param cmd
         * @return
         */
        public CmdExecutor cmd(String cmd){
            if(null != cmd && 0 != cmd.length()){
                cmds.add(String.format("%s %s",cmd,getRedirect()));                 
            }
            return this;
        }
        private List<String> build(){
            return cmds.isEmpty()
                    ? Collections.<String>emptyList()
                    : Arrays.asList(SHELL_NAME,SHELL_PARAM,join(cmds,cmdSeparator));
        }
        private static String join(List<String> strs,String separator) {
            StringBuffer buffer = new StringBuffer();
            for(int i=0;i<strs.size();++i){
                if(i>0){
                    buffer.append(separator);
                }
                buffer.append(strs.get(i));
            }
            return buffer.toString();
        }
        /**
         * 将{@link InputStream}中所有内容输出到{@link StringBuffer}
         * @param in
         * @return
         * @throws IOException
         */
        private static void toBuffer(InputStream in,StringBuffer buffer) throws IOException{
            if(null == in || null == buffer){
                return ;
            }
            InputStreamReader ir = new InputStreamReader(in);
            LineNumberReader input = new LineNumberReader(ir);
            try{
                String line;
                while ((line = input.readLine()) != null) {
                    buffer.append(line).append("\n");
                }
            }finally{
                input.close();
            }
        }
        /** 
         * 调用{@link Runtime#exec(String[])}执行命令 
         * @return 返回输出结果 
         */
        public String exec() throws IOException{
            StringBuffer outBuffer = new StringBuffer();
            exec(outBuffer,null);
            return outBuffer.toString();
        }
        /**
         * 调用{@link Runtime#exec(String[])}执行命令 
         * @param outBuffer 标准输出
         * @param errBuffer 错误信息输出
         * @throws IOException
         */
        public void exec(StringBuffer outBuffer,StringBuffer errBuffer) throws IOException{
            List<String> cmdlist = build();
            if(!cmdlist.isEmpty()){
                if(verbose){
                    logger.info(join(cmdlist," "));
                }
                Process process = Runtime.getRuntime().exec(cmdlist.toArray(new String[cmdlist.size()]));
                if(sync){
                    try {
                        process.waitFor();
                    } catch (InterruptedException e) {
                    }
                }
                toBuffer(process.getInputStream(),outBuffer);
                toBuffer(process.getErrorStream(),errBuffer);
            }
        }
    }

使用示例如下：

import static org.junit.Assert.*;
    
    public class CmdExecutorTest {
        
    
        @Test
        public void test() {
            try {
                // 创建一个CmdExecutor实例，通过sudoCmd或cmd添加要执行的命令，最后调用exec执行。
                String out = CmdExecutor.builder("sudopassword")
                .errRedirect(false)
                .sudoCmd("date -s '2016-12-27 23:23:23'")// 修改系统时间
                .sudoCmd("clock -w")
                .sudoCmd("cat /etc/sysconfig/network")
                .cmd("date")
                .sudoCmd("ntpdate -u time.windows.com")// 系统时间同步
                .exec();
                System.out.println(out);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
    }

> 代码仓库地址:  
> [https://gitee.com/l0km/common-java/blob/master/common-base/src/test/java/net/gdface/common/CmdExecutorTest.java][https_gitee.com_l0km_common-java_blob_master_common-base_src_test_java_net_gdface_common_CmdExecutorTest.java]

# 参考资料 #

《解决sudo: sorry, you must have a tty to run sudo》[http://blog.csdn.net/breezehappy/article/details/38895375][http_blog.csdn.net_breezehappy_article_details_38895375]

[SouthEast]: /images/20220602/aff2fa14a72840f8ad8b2a17c9c09f69.png
[https_gitee.com_l0km_common-java_blob_master_common-base_src_main_java_net_gdface_utils_CmdExecutor.java]: https://gitee.com/l0km/common-java/blob/master/common-base/src/main/java/net/gdface/utils/CmdExecutor.java
[https_gitee.com_l0km_common-java_blob_master_common-base_src_test_java_net_gdface_common_CmdExecutorTest.java]: https://gitee.com/l0km/common-java/blob/master/common-base/src/test/java/net/gdface/common/CmdExecutorTest.java
[http_blog.csdn.net_breezehappy_article_details_38895375]: http://blog.csdn.net/breezehappy/article/details/38895375