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@secabstraction
Last active April 1, 2024 21:03
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function Export-MFT {
<#
.SYNOPSIS
Extracts master file table from volume.
Version: 0.1
Author : Jesse Davis (@secabstraction)
License: BSD 3-Clause
.DESCRIPTION
This module exports the master file table (MFT) and writes it to $env:TEMP.
The object(s) output by this module specify the path of the written MFT file for retrieval via Copy-Item -Path \\NetworkPath\C$
.PARAMETER ComputerName
Specify host(s) to retrieve data from.
.PARAMETER ThrottleLimit
Specify maximum number of simultaneous connections.
.PARAMETER Volume
Specify a volume to retrieve its master file table.
.PARAMETER CSV
Specify path to output file, output is formatted as comma separated values.
.EXAMPLE
The following example extracts the master file table from the local system volume and writes it to TEMP.
PS C:\> Export-MFT
.EXAMPLE
The following example extracts the master file table from the system volume of Server01 and writes it to TEMP.
PS C:\> Export-MFT -ComputerName Server01
.EXAMPLE
The following example extracts the master file table from the F volume on Server01 and writes it to TEMP.
PS C:\> Export-MFT -ComputerName Server01 -Volume F
.NOTES
.INPUTS
.OUTPUTS
.LINK
#>
[CmdLetBinding()]
Param(
[Parameter(Position = 0, ValueFromPipeline = $true)]
[ValidateNotNullOrEmpty()]
[String[]]$ComputerName,
[Parameter()]
[ValidateNotNullOrEmpty()]
[Int]$ThrottleLimit = 10,
[Parameter()]
[ValidateNotNullOrEmpty()]
[Char]$Volume = 0,
[Parameter()]
[ValidateNotNullOrEmpty()]
[String]$CSV
) #End Param
$ScriptTime = [Diagnostics.Stopwatch]::StartNew()
$RemoteScriptBlock = {
Param($Volume)
if ($Volume -ne 0) {
$Win32_Volume = Get-WmiObject -Class Win32_Volume -Filter "DriveLetter LIKE '$($Volume):'"
if ($Win32_Volume.FileSystem -ne "NTFS") {
Write-Error "$Volume is not an NTFS filesystem."
break
}
}
else {
$Win32_Volume = Get-WmiObject -Class Win32_Volume -Filter "DriveLetter LIKE '$($env:SystemDrive)'"
if ($Win32_Volume.FileSystem -ne "NTFS") {
Write-Error "$env:SystemDrive is not an NTFS filesystem."
break
}
}
$OutputFilePath = $env:TEMP + "\$([IO.Path]::GetRandomFileName())"
#region WinAPI
$GENERIC_READWRITE = 0x80000000
$FILE_SHARE_READWRITE = 0x02 -bor 0x01
$OPEN_EXISTING = 0x03
$DynAssembly = New-Object System.Reflection.AssemblyName('MFT')
$AssemblyBuilder = [AppDomain]::CurrentDomain.DefineDynamicAssembly($DynAssembly, [Reflection.Emit.AssemblyBuilderAccess]::Run)
$ModuleBuilder = $AssemblyBuilder.DefineDynamicModule('InMemory', $false)
$TypeBuilder = $ModuleBuilder.DefineType('kernel32', 'Public, Class')
$DllImportConstructor = [Runtime.InteropServices.DllImportAttribute].GetConstructor(@([String]))
$SetLastError = [Runtime.InteropServices.DllImportAttribute].GetField('SetLastError')
$SetLastErrorCustomAttribute = New-Object Reflection.Emit.CustomAttributeBuilder($DllImportConstructor,
@('kernel32.dll'),
[Reflection.FieldInfo[]]@($SetLastError),
@($True))
#CreateFile
$PInvokeMethodBuilder = $TypeBuilder.DefinePInvokeMethod('CreateFile', 'kernel32.dll',
([Reflection.MethodAttributes]::Public -bor [Reflection.MethodAttributes]::Static),
[Reflection.CallingConventions]::Standard,
[IntPtr],
[Type[]]@([String], [Int32], [UInt32], [IntPtr], [UInt32], [UInt32], [IntPtr]),
[Runtime.InteropServices.CallingConvention]::Winapi,
[Runtime.InteropServices.CharSet]::Ansi)
$PInvokeMethodBuilder.SetCustomAttribute($SetLastErrorCustomAttribute)
#CloseHandle
$PInvokeMethodBuilder = $TypeBuilder.DefinePInvokeMethod('CloseHandle', 'kernel32.dll',
([Reflection.MethodAttributes]::Public -bor [Reflection.MethodAttributes]::Static),
[Reflection.CallingConventions]::Standard,
[Bool],
[Type[]]@([IntPtr]),
[Runtime.InteropServices.CallingConvention]::Winapi,
[Runtime.InteropServices.CharSet]::Auto)
$PInvokeMethodBuilder.SetCustomAttribute($SetLastErrorCustomAttribute)
$Kernel32 = $TypeBuilder.CreateType()
#endregion WinAPI
# Get handle to volume
if ($Volume -ne 0) { $VolumeHandle = $Kernel32::CreateFile(('\\.\' + $Volume + ':'), $GENERIC_READWRITE, $FILE_SHARE_READWRITE, [IntPtr]::Zero, $OPEN_EXISTING, 0, [IntPtr]::Zero) }
else {
$VolumeHandle = $Kernel32::CreateFile(('\\.\' + $env:SystemDrive), $GENERIC_READWRITE, $FILE_SHARE_READWRITE, [IntPtr]::Zero, $OPEN_EXISTING, 0, [IntPtr]::Zero)
$Volume = ($env:SystemDrive).TrimEnd(':')
}
if ($VolumeHandle -eq -1) {
Write-Error "Unable to obtain read handle for volume."
break
}
# Create a FileStream to read from the volume handle
$FileStream = New-Object IO.FileStream($VolumeHandle, [IO.FileAccess]::Read)
# Read VBR from volume
$VolumeBootRecord = New-Object Byte[](512)
if ($FileStream.Read($VolumeBootRecord, 0, $VolumeBootRecord.Length) -ne 512) { Write-Error "Error reading volume boot record." }
# Parse MFT offset from VBR and set stream to its location
$MftOffset = [Bitconverter]::ToInt32($VolumeBootRecord[0x30..0x37], 0) * 0x1000
$FileStream.Position = $MftOffset
# Read MFT's file record header
$MftFileRecordHeader = New-Object byte[](48)
if ($FileStream.Read($MftFileRecordHeader, 0, $MftFileRecordHeader.Length) -ne $MftFileRecordHeader.Length) { Write-Error "Error reading MFT file record header." }
# Parse values from MFT's file record header
$OffsetToAttributes = [Bitconverter]::ToInt16($MftFileRecordHeader[0x14..0x15], 0)
$AttributesRealSize = [Bitconverter]::ToInt32($MftFileRecordHeader[0x18..0x21], 0)
# Read MFT's full file record
$MftFileRecord = New-Object byte[]($AttributesRealSize)
$FileStream.Position = $MftOffset
if ($FileStream.Read($MftFileRecord, 0, $MftFileRecord.Length) -ne $AttributesRealSize) { Write-Error "Error reading MFT file record." }
# Parse MFT's attributes from file record
$Attributes = New-object byte[]($AttributesRealSize - $OffsetToAttributes)
[Array]::Copy($MftFileRecord, $OffsetToAttributes, $Attributes, 0, $Attributes.Length)
# Find Data attribute
$CurrentOffset = 0
do {
$AttributeType = [Bitconverter]::ToInt32($Attributes[$CurrentOffset..$($CurrentOffset + 3)], 0)
$AttributeSize = [Bitconverter]::ToInt32($Attributes[$($CurrentOffset + 4)..$($CurrentOffset + 7)], 0)
$CurrentOffset += $AttributeSize
} until ($AttributeType -eq 128)
# Parse data attribute from all attributes
$DataAttribute = $Attributes[$($CurrentOffset - $AttributeSize)..$($CurrentOffset - 1)]
# Parse MFT size from data attribute
$MftSize = [Bitconverter]::ToUInt64($DataAttribute[0x30..0x37], 0)
# Parse data runs from data attribute
$OffsetToDataRuns = [Bitconverter]::ToInt16($DataAttribute[0x20..0x21], 0)
$DataRuns = $DataAttribute[$OffsetToDataRuns..$($DataAttribute.Length -1)]
# Convert data run info to string[] for calculations
$DataRunStrings = ([Bitconverter]::ToString($DataRuns)).Split('-')
# Setup to read MFT
$FileStreamOffset = 0
$DataRunStringsOffset = 0
$TotalBytesWritten = 0
$MftData = New-Object byte[](0x1000)
$OutputFileStream = [IO.File]::OpenWrite($OutputFilePath)
do {
$StartBytes = [int]($DataRunStrings[$DataRunStringsOffset][0]).ToString()
$LengthBytes = [int]($DataRunStrings[$DataRunStringsOffset][1]).ToString()
$DataRunStart = "0x"
for ($i = $StartBytes; $i -gt 0; $i--) { $DataRunStart += $DataRunStrings[($DataRunStringsOffset + $LengthBytes + $i)] }
$DataRunLength = "0x"
for ($i = $LengthBytes; $i -gt 0; $i--) { $DataRunLength += $DataRunStrings[($DataRunStringsOffset + $i)] }
$FileStreamOffset += ([int]$DataRunStart * 0x1000)
$FileStream.Position = $FileStreamOffset
for ($i = 0; $i -lt [int]$DataRunLength; $i++) {
if ($FileStream.Read($MftData, 0, $MftData.Length) -ne $MftData.Length) {
Write-Warning "Possible error reading MFT data on $env:COMPUTERNAME."
}
$OutputFileStream.Write($MftData, 0, $MftData.Length)
$TotalBytesWritten += $MftData.Length
}
$DataRunStringsOffset += $StartBytes + $LengthBytes + 1
} until ($TotalBytesWritten -eq $MftSize)
$FileStream.Dispose()
$OutputFileStream.Dispose()
$Properties = @{
NetworkPath = "\\$($env:COMPUTERNAME)\C$\$($OutputFilePath.TrimStart('C:\'))"
ComputerName = $env:COMPUTERNAME
'MFT Size' = "$($MftSize / 1024 / 1024) MB"
'MFT Volume' = $Volume
'MFT File' = $OutputFilePath
}
New-Object -TypeName PSObject -Property $Properties
}
if ($PSBoundParameters['ComputerName']) {
$ReturnedObjects = Invoke-Command -ComputerName $ComputerName -ScriptBlock $RemoteScriptBlock -ArgumentList @($Volume) -SessionOption (New-PSSessionOption -NoMachineProfile) -ThrottleLimit $ThrottleLimit
}
else { $ReturnedObjects = Invoke-Command -ScriptBlock $RemoteScriptBlock -ArgumentList @($Volume) }
if ($ReturnedObjects -ne $null) {
if ($PSBoundParameters['CSV']) { $ReturnedObjects | Export-Csv -Path $OutputFilePath -Append -NoTypeInformation -ErrorAction SilentlyContinue }
else { Write-Output $ReturnedObjects }
}
[GC]::Collect()
$ScriptTime.Stop()
Write-Verbose "Done, execution time: $($ScriptTime.Elapsed)"
}
@ImLenny
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ImLenny commented Sep 8, 2022

Is this script designed to be run as a standalone script or as part of a PowerShell module? I don't seem to be able to run the script (using the Command example from Line 39 running on my own host) and I'm not sure why

@vikas891
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@ImLenny Unsure if you found the answer but the code snippet is only a function. You need to "call" it in order for it to execute. You can add a Export-MFT at the very end of the PS1, save and fire it!

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