Setting the embedded script in a PowerShell Session

Alexandre Bélisle
Posts: 100

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Hello @everyone

A member of our community recently asked if there were a way to set the Embedded Script of a PowerShell Session programatically.
Before even trying to solve this challenge, he came back up to us with solution;
We thought it would be interesting to share his solution with our beloved community.

So here it goes:

function Get-CompressedByteArray
# This function actually does all the encrytion necessay to populate
{
[CmdletBinding()]
Param
(
[Parameter(Mandatory,ValueFromPipeline,ValueFromPipelineByPropertyName)][byte[]] $byteArray = $(Throw("-byteArray is required"))
)
Process
{
# Write-Verbose "Get-CompressedByteArray"
[System.IO.MemoryStream] $output = New-Object System.IO.MemoryStream
$gzipStream = New-Object System.IO.Compression.DeflateStream $output, ([IO.Compression.CompressionMode]::Compress)
$gzipStream.Write( $byteArray, 0, $byteArray.Length )
$gzipStream.Close()
$output.Close()
$tmp = $output.ToArray()
# Write-Output $tmp
}
}

$InlineScript = '<paste the scripot you want to input in the embedded script section>'

$bytes = [System.Text.Encoding]::ASCII.GetBytes($InlineScript)
$CompressedBytes = Get-CompressedByteArray $bytes

at this point, we get a fully functional compressed string that will be easily set to the EmbeddedScriptCompressed property of a powershell session, such as :
# if applicable, Import the RDM Powershell Module

$s = Get-RDMSession -Name "name of the session you want to set the embedded script into"
$s.PowerShell.EmbeddedScriptCompressed = $CompressedBytes
Set-RDMSession $s

Regards,

Alexandre Bélisle
Posts: 100

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Hello @everyone

Additionally, we can apply this the other way around to read the content of an already set PowerShell Session :

function Get-DecompressedByteArray {

[CmdletBinding()]
Param
(
[Parameter(Mandatory,ValueFromPipeline,ValueFromPipelineByPropertyName)]
[byte[]] $byteArray = $(Throw("-byteArray is required"))
)
Process
{
# Write-Verbose "Get-DecompressedByteArray"
$input = New-Object System.IO.MemoryStream( , $byteArray )
$output = New-Object System.IO.MemoryStream
$gzipStream = New-Object System.IO.Compression.DeflateStream $input, ([IO.Compression.CompressionMode]:ecompress)
$gzipStream.CopyTo( $output )
$gzipStream.Close()
$input.Close()
[byte[]] $byteOutArray = $output.ToArray()
# Write-Output $byteOutArray
}
}

$s = Get-RDMSession -Name "name of the session you want to get the embedded script from"
$DecompressedBytes = Get-DecompressedByteArray ($s.PowerShell.EmbeddedScriptCompressed)

# display the text

Write-Host ( $enc.GetString( $decompressedByteArray ) | Out-String )

Regards,