PowerShell :: Import Barracuda Sender Policy CSV into MS365 Anti-Spam Allow//Block Lists

Import-BarracudaCSVToMS365.ps1

param (
    [string]$CsvPath = (Join-Path $PSScriptRoot 'AllowList.csv'),
    [string]$MS365User = 'coolguy@coolcompany.com',
    [string]$BarracudaQuarantineEmail = 'quarantine@ess.ca.barracudanetworks.com',
    [switch]$IncludeBlockLists
)

$getSessions = Get-PSSession | Select-Object -Property State, Name
$isConnected = [bool](@($getSessions) -like '@{State=Opened; Name=ExchangeOnlineInternalSession*').Count -gt 0
If (!$isConnected) {
	Connect-ExchangeOnline -UserPrincipalName $MS365User
}

$csvContent = Get-Content -Path $CsvPath
# Keep only the first two columns, and fix 'Policy' column (2) header.
$trimmedCsvContent = $csvContent -replace '^(.*?,.*?),.*$', '$1' -replace 'Policy \(block', 'Policy'
# Convert to an array of objects.
$list = ConvertFrom-Csv $trimmedCsvContent

# Create individual, MS365 compatible lists.
$emailAllowList = [string[]]($list | Where-Object {($_.Policy -eq 'exempt') -and ($_."Email Address" -like '*@*') -and ($_."Email Address" -notmatch '\*')})."Email Address"

# Append Barracuda email address.
if ($BarracudaQuarantineEmail -notin $emailAllowList) {
    Write-Host ('Appending Barracuda quarantine email address to Allow list...')
    $emailAllowList += $BarracudaQuarantineEmail
}

$emailAllowList = $emailAllowList | Sort-Object

$domainAllowList = [string[]]($list | Where-Object {($_.Policy -eq 'exempt') -and ($_."Email Address" -notlike '*@*') -and ($_."Email Address" -notmatch '\*')})."Email Address" | Sort-Object

Write-Host ('Allowed Email Addresses: {0}' -f $emailAllowList.Count)
Write-Host ('Allowed Email Domains: {0}' -f $domainAllowList.Count)

Write-Host 'Updating (replacing) existing Allow lists...'
Set-HostedContentFilterPolicy -Identity 'Default' -AllowedSenders $emailAllowList -AllowedSenderDomains $domainAllowList

if ($IncludeBlockLists) {
    $emailBlockList = [string[]]($list | Where-Object {($_.Policy -eq 'block') -and ($_."Email Address" -like '*@*') -and ($_."Email Address" -notmatch '\*')})."Email Address" | Sort-Object

    $domainBlockList = [string[]]($list | Where-Object {($_.Policy -eq 'block') -and ($_."Email Address" -notlike '*@*') -and ($_."Email Address" -notmatch '\*')})."Email Address" | Sort-Object

    Write-Host ('Blocked Email Addresses: {0}' -f $emailBlockList.Count)
    Write-Host ('Blocked Email Domains: {0}' -f $domainBlockList.Count)

    Write-Host 'Updating (replacing) existing Block lists...'
    Set-HostedContentFilterPolicy -Identity 'Default' -BlockedSenders $emailBlockList -BlockedSenderDomains $domainBlockList
}