我的解决方案相当冗长,但它做了一些其他必要的事情来通过 ssh 可靠地运行命令:
要通过 SSH 自动执行 sudo,我们可以使用Expect
- 这就像 Linux 上的同名工具一样,可以让你交互响应。它会等待,直到有一些输出与模式匹配,例如密码提示。
如果您有一系列 sudo 操作,您可能会遇到不可预测的时间,直到 sudo 需要重新身份验证,因此 sudo 可能需要也可能不需要身份验证,我们无法确定。
自动化时的一个大问题是了解命令是否失败。唯一了解的方法是通过 shell 获取最后一个错误。我抛出非零。
可能需要根据您的配置自定义与 shell 提示符匹配的正则表达式。各种各样的东西都可能被注入到提示中。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using Renci.SshNet;
using Renci.SshNet.Common;
namespace Example
{
public class Log
{
public static void Verbose(string message) =>
Console.WriteLine(message);
public static void Error(string message) =>
Console.WriteLine(message);
}
public static class StringExt
{
public static string StringBeforeLastRegEx(this string str, Regex regex)
{
var matches = regex.Matches(str);
return matches.Count > 0
? str.Substring(0, matches.Last().Index)
: str;
}
public static bool EndsWithRegEx(this string str, Regex regex)
{
var matches = regex.Matches(str);
return
matches.Count > 0 &&
str.Length == (matches.Last().Index + matches.Last().Length);
}
public static string StringAfter(this string str, string substring)
{
var index = str.IndexOf(substring, StringComparison.Ordinal);
return index >= 0
? str.Substring(index + substring.Length)
: "";
}
public static string[] GetLines(this string str) =>
Regex.Split(str, "\r\n|\r|\n");
}
public static class UtilExt
{
public static void ForEach<T>(this IEnumerable<T> sequence, Action<T> func)
{
foreach (var item in sequence)
{
func(item);
}
}
}
public class Ssh
{
SshClient sshClient;
ShellStream shell;
string pwd = "";
string lastCommand = "";
static Regex prompt = new Regex("[a-zA-Z0-9_.-]*\\@[a-zA-Z0-9_.-]*\\:\\~[#$] ", RegexOptions.Compiled);
static Regex pwdPrompt = new Regex("password for .*\\:", RegexOptions.Compiled);
static Regex promptOrPwd = new Regex(Ssh.prompt + "|" + Ssh.pwdPrompt);
public void Connect(string url, int port, string user, string pwd)
{
Log.Verbose($"Connect Ssh: {user}@{pwd}:{port}");
var connectionInfo =
new ConnectionInfo(
url,
port,
user,
new PasswordAuthenticationMethod(user, pwd));
this.pwd = pwd;
this.sshClient = new SshClient(connectionInfo);
this.sshClient.Connect();
var terminalMode = new Dictionary<TerminalModes, uint>();
terminalMode.Add(TerminalModes.ECHO, 53);
this.shell = this.sshClient.CreateShellStream("", 0, 0, 0, 0, 4096, terminalMode);
try
{
this.Expect(Ssh.prompt);
}
catch (Exception ex)
{
Log.Error("Exception - " + ex.Message);
throw;
}
}
public void Disconnect()
{
Log.Verbose($"Ssh Disconnect");
this.sshClient?.Disconnect();
this.sshClient = null;
}
void Write(string commandLine)
{
Console.ForegroundColor = ConsoleColor.Green;
Log.Verbose("> " + commandLine);
Console.ResetColor();
this.lastCommand = commandLine;
this.shell.WriteLine(commandLine);
}
string Expect(Regex expect, double timeoutSeconds = 60.0)
{
var result = this.shell.Expect(expect, TimeSpan.FromSeconds(timeoutSeconds));
if (result == null)
{
throw new Exception($"Timeout {timeoutSeconds}s executing {this.lastCommand}");
}
result = result.Contains(this.lastCommand) ? result.StringAfter(this.lastCommand) : result;
result = result.StringBeforeLastRegEx(Ssh.prompt);
result = result.Trim();
result.GetLines().ForEach(x => Log.Verbose(x));
return result;
}
public string Execute(string commandLine, double timeoutSeconds = 30.0)
{
Exception exception = null;
var result = "";
var errorMessage = "failed";
var errorCode = "exception";
try
{
this.Write(commandLine);
result = this.Expect(Ssh.promptOrPwd);
if (result.EndsWithRegEx(pwdPrompt))
{
this.Write(this.pwd);
this.Expect(Ssh.prompt);
}
this.Write("echo $?");
errorCode = this.Expect(Ssh.prompt);
if (errorCode == "0")
{
return result;
}
else if (result.Length > 0)
{
errorMessage = result;
}
}
catch (Exception ex)
{
exception = ex;
errorMessage = ex.Message;
}
throw new Exception($"Ssh error: {errorMessage}, code: {errorCode}, command: {commandLine}", exception);
}
}
}
然后像这样使用它:
var client = new Ssh(IP, 22, username, password);
var output = client.Execute("sudo -S find . -name 29172");