Ing. Ondřej Ševeček MCSM:Directory | MVP:Enterprise Security | Certified Ethical Hacker | MCSE:SharePoint | PowerShell for developers

Why the admins use PowerShell  Newer command line marketing –older VBScript still supported but with limited functionality  Script from command line or textual.PS1 files –extensive object oriented pipeline –support for CMD, EXE, D/COM, NET (plus Win32API through PINVOKE)

Why developers might be interested  Provide Admins with familiar interface for custom applications –own cmdlets in NET  Automate own tasks –builds, file distribution, signing, packaging etc.  Develop installation tasks –MSIEXEC custom actions - external  Test / validate / proof of concept –which is non-compiled, quickly written

Example: Object pipe Get-Process, Stop-Process Export-Csv, Import-Csv Import-CliXml, Export-CliXml CERTUTIL | ConvertFrom-Csv New-Object System.DirectoryServices.DirectoryEntry New-Object System.DirectoryServices.DirectorySearcher [System.Collections.ArrayList] [System.Collections.Hashtable] DSQUERY | Get-WmiObject

PowerShell versions  Version 1 –download for Windows XP and 2003 and Vista –built into Windows 2008  Version 2 –download for Windows XP and 2003, Vista, 2008 –built into Windows 7 and 2008 R2 –NetFx 2.0 CLR  Version 3 –download for Windows 7 and 2008 R2 –built into Windows 8 and 2012 –NetFx 4.0 CLR  Version 4 –download for Windows 7 and 2008 R2, 8 and 2012 –built into Windows 8.1 and 2012 R2 –NetFx 4.5 CLR  Download as Windows Management Framework

Determine version  $psVersionTable  Get-Host  powershell -v 2, powershell -v 3

Script development environment  Notepad  PowerShell ISE  third-party free download –not necessary anymore since Windows 8

Basic language elements  Variables, values and constants –$true, $false, 0x38B, $null –'string', "string", (1..30)  Types (objects vs. structs)  Operators –-eq/-ceq, -ge/-gt, -le/-lt, -like, -clike, -match, -cmatch, -join, -split, -f, -is –-and, -or, -not, !, -xor, -band, -bor, -not, -bxor –*, /, %  Conditions  While, Do While, Foreach, break, continue  Switch  Functions

String and Date methods  [String] –ToLower() –ToUpper() –Split() –Trim()  [DateTime] –AddDays() –Parse()

Object wrappers (adapters)  Get-Member .psbase,.psadapted,.psextended,.psobject –Get-Process, [XML]

Weird access to non-existing members .NonExistentProperty - no efect, empty .NonExistentMethod() - exception  $array[outsideIndex] - exception

Example: COM objects $word = New-Object -ComObject 'Word.Application' $doc = $word.Documents.Add() $range = $doc.Range() $range.Font.Size = 20 $range.Font.Name = 'Verdana' $range.ParagraphFormat.Alignment = 2 $range.Text = 'Hellow world' $docName = 'c:\public\hello.docx' $doc.SaveAs([ref] $docName) $word.Quit()

Example: Static methods and properties  [System.Text.ASCIIEncoding]::ASCII.GetBytes()  [System.Math]::PI  [Math]::Round()  [Convert]::ToBase64String()  [BitConverter]::ToString()

Type accelerators  [ADSI]  [WMICLASS]  [XML]

Custom objects  New-Object PSCustomObject  Add-Member

Weird array 3, 2, 8, 11) -gt (Get-Date), $null, 2, $null, 11) -ne $null

Weir parameter parsing  Parsing in command mode –everything is string except for variables and things in parenthesis –watch out for array goes just with comma separator,  Parsing in expression mode  First token switches the mode: –letter, &,.,. –number, variable, quoted string

Weird default values and conversions  [string] $nothing = $null  [int] $noNumber = $null  [StringBuilder] $noStrBuilder = $null  [int] '55'  '38' * 3  '38' + '95'  95 + '11'  [string] (Get-Process)  Get-Process | fl * | Out-String

Weird collection member functions  PowerShell 3 and newer  If the member does not exist in the collection itself, it gets called on all members

Weird function return values  Whatever goes to pipe in function is returned in array  If you return single-item array it gets converted into a single object  If you return [ArrayList], it converts to [Object[]]

Example: SHA1 $name = 'zkusebni retezec' $nameBytes = [System.Text.ASCIIEncoding]::ASCII.GetBytes($name) $sha = New-Object System.Security.Cryptography.SHA1CryptoServiceProvider $hashBytes = $sha.ComputeHash($nameBytes) # bytes array (20 bytes as SHA-1 is always 160bits) $hashBytes # the same in Base64 [Convert]::ToBase64String($hashBytes) # the same in Hex [BitConverter]::ToString($hashBytes)

C# from PowerShell  Here strings at the end of a line –end as the first character on an empty line Add-Type -TypeDefinition $hereStringDef Add-Type -AssemblyName 'My.Assembly.Name' Add-Type -Path 'c:\projects\myassemblyname.dll' [System.Reflection.Assembly]::LoadFile('…')

Example: Cookie-aware WebClient $typeCookieAwareWebClient namespace Sevecek { public class CookieAwareWebClient : System.Net.WebClient { private System.Net.CookieContainer cookieContainer = new System.Net.CookieContainer(); protected override System.Net.WebRequest GetWebRequest(System.Uri address) { System.Net.WebRequest baseRequest = base.GetWebRequest(address); if (baseRequest is System.Net.HttpWebRequest) { (baseRequest as System.Net.HttpWebRequest).CookieContainer = cookieContainer; } return baseRequest; } if (-not ('Sevecek.CookieAwareWebClient' -as [type])) { Add-Type -TypeDefinition $typeCookieAwareWebClient }

Weird struct assignment $structs namespace Sevecek { public struct subStruct { public string name; public int age; } public struct parentStruct { public string id; public subStruct person; } Add-Type -TypeDefinition $structs $onePerson = New-Object parentStruct $onePerson.person.name = 'ondrej' $onePerson.person

Exception handling try { throw } catch [type] {} finally {} $error -ErrorAction $errorActionPreference throw 'some error' throw (Get-Process)[5]

Win32API with PINVOKE 

Custom CMDLETs in C#  using System.Management.Automation  Class for each cmdlet - decorated as cmdlet  Public properties as parameters - decorated again  Override void processing methods –WriteObject() to pipeline  us/library/dd878294(v=vs.85).aspx

Kurzy Počítačové školy Gopas na GOC171 - Active Directory Troubleshooting GOC172 - Kerberos Troubleshooting GOC173 - Enterprise PKI GOC174 - SharePoint 2013 Troubleshooting GOC175 - Advanced Security GOC169 - Auditing ISO/IEC 2700x Získejte tričko TechEd 2014 za vyplněný hodnotící dotazník. Počítačová škola Gopas – Vaše IT škola života