象运行可执行文件一样,Powershell运行文件和脚本,也必须使用绝对路径或者相对路径,或者要运行的文件必须定义在可受信任的环境变量中。
关于脚本
脚本和批处理都属于伪可执行文件,它们只是包含了若干命令行解释器能够解释和执行的命令行代码。
执行批处理文件
批处理是扩展名为”.bat”的文本文件,它可以包含任何cmd控制台能够处理的命令。当批处理文件被打开,Cmd控制台会逐行执行每条命令。那Powershell能够直接执行批处理吗?
将下列命令保存为ping.bat
@echo off echo batch File Test pause Dir %windir%/system
然后执行ping
屏幕会打印ping命令帮助,说明调用的ping cmd 而不是ping.bat。
改为:
PS C:\PS> ./ping batch File Test Press any key to continue . . . Volume in drive C has no label. Volume Serial Number is 4E9B-D846 Directory of C:Windowssystem 2009/06/11 05:21 69,584 avicap.dll 2009/06/11 05:21 109,456 avifile.dll 2009/07/14 05:41 32,816 COMMDLG.DLL 2009/07/14 05:41 2,000 keyboard.drv 2009/06/11 05:42 9,936 lzexpand.dll 2009/06/11 05:21 73,376 mciavi.drv 2009/06/11 05:21 25,264 mciseq.drv 2009/06/11 05:21 28,160 mciwave.drv 2009/07/14 05:41 68,992 MMSYSTEM.DLL 2009/07/14 05:41 1,152 mmtask.tsk 2009/07/14 05:41 2,032 mouse.drv 2009/06/11 05:21 126,912 msvideo.dll 2009/06/11 05:42 82,944 olecli.dll 2009/07/14 05:41 24,064 OLESVR.DLL 2009/07/14 05:41 5,120 SHELL.DLL 2009/07/14 05:41 1,744 sound.drv 2009/06/11 05:25 5,532 stdole.tlb 2009/07/14 05:41 3,360 system.drv 2009/07/14 05:41 4,048 TIMER.DRV 2009/06/11 05:42 9,008 ver.dll 2009/07/14 05:41 2,176 vga.drv 2009/07/14 05:41 12,704 WFWNET.DRV 22 File(s) 700,380 bytes 2 Dir(s) 75,927,420,928 bytes free
这时运行的是批处理。
通过cmd进入cmd控制台输入ping发现执行的不是ping命令,而是直接运行ping.bat ,也就是说可以通过.bat 覆盖cmd命令。这种机制很危险,如果有人侵入电脑,并将系统内部命令篡改成自己批处理,那就太悲剧了。 这种命令与脚本的混淆不会发生在powershell中,因为powershell有更安全的机制。
执行VB脚本文件
将下列命令保存为test.vbs
Set wmi = GetObject("winmgmts:") Set collection = wmi.ExecQuery("select * from Win32_Process") For Each process in collection WScript.Echo process.getObjectText_ Next
执行 .\test.vbs 会遍历当前Win32进程,并把每个进程的详细信息通过窗口显示出来。
怎样让VB脚本的通过控制台输出呢?
Wscript //H:CScript
怎样还原VB脚本通过窗口输出呢?
WScript //H:WScript
在powershell中执行VB脚本
PS C:\PS> cscript.exe .test.vbs Microsoft (R) Windows Script Host Version 5.8 Copyright (C) Microsoft Corporation. All rights reserved. instance of Win32_Process { Caption = "System Idle Process"; CreationClassName = "Win32_Process"; CSCreationClassName = "Win32_ComputerSystem"; CSName = "test-me-01"; Description = "System Idle Process"; Handle = "0"; HandleCount = 0; KernelModeTime = "484113379271"; Name = "System Idle Process"; OSCreationClassName = "Win32_OperatingSystem"; OSName = "Microsoft Windows 7 Enterprise |C:Windows|DeviceHarddisk0Partition2"; OtherOperationCount = "0"; OtherTransferCount = "0"; PageFaults = 0; PageFileUsage = 0; ParentProcessId = 0; PeakPageFileUsage = 0; PeakVirtualSize = "0"; PeakWorkingSetSize = 0; Priority = 0; PrivatePageCount = "0"; ProcessId = 0; QuotaNonPagedPoolUsage = 0; QuotaPagedPoolUsage = 0; QuotaPeakNonPagedPoolUsage = 0; QuotaPeakPagedPoolUsage = 0; ReadOperationCount = "0"; ReadTransferCount = "0"; SessionId = 0; ThreadCount = 2; UserModeTime = "0"; VirtualSize = "0"; WindowsVersion = "6.1.7601"; WorkingSetSize = "24576"; WriteOperationCount = "0"; WriteTransferCount = "0"; };
执行powershell脚本
Powershell拥有自己的脚本,扩展名为“.ps1”
PS C:\PS> echo "dir;Get-PSProvider;help dir" >test.ps1 PS C:\PS> Get-Content ./test.ps1 dir;Get-PSProvider;help dir PS C:\PS> ./test.ps1初次执行脚本时,可能会碰到一个异常: File ” C:\PS\test.ps1″ cannot be loaded because the execution of scripts is disabled on this system. Please see “get-help about_signing” for more details. At line:1 char:10 + .test.ps1 <<<<
这是powershell的默认安全设置禁用了执行脚本,要启用这个功能需要拥有管理员的权限。
Powershell调用入口的优先级
别名:控制台首先会寻找输入是否为一个别名,如果是,执行别名所指的命令。因此我们可以通过别名覆盖任意powershell命令,因为别名的优先级最高。
函数:如果没有找到别名,会继续寻找函数,函数类似别名,只不过它包含了更多的powershell命令。因此可以自定义函数扩充cmdlet 把常用的参数给固化进去。
命令:如果没有找到函数,控制台会继续寻找命令,即cmdlet,powershell的内部命令。
脚本:没有找到命令,继续寻找扩展名为“.ps1”的Powershell脚本。
文件:没有找到脚本,会继续寻找文件,如果没有可用的文件,控制台会抛出异常。
The term ‘now' is not recognized as the name of a cmdlet, function, script file, or operable program. Chec g of the name, or if a path was included, verify that the path is correct and try again. At line:1 char:4 + now <<<< + CategoryInfo : ObjectNotFound: (now:String) [], CommandNotFoundException + FullyQualifiedErrorId : CommandNotFoundException