Manage Windows Advanced Firewall with PowerShell

gistfile1.ps1

Set-StrictMode -Version Latest

# Constants
if (!(Test-Path variable:\NET_FW_DISABLED))        { Set-Variable NET_FW_DISABLED        $False }
if (!(Test-Path variable:\NET_FW_ENABLED))         { Set-Variable NET_FW_ENABLED         $True }
if (!(Test-Path variable:\NET_FW_IP_PROTOCOL_TCP)) { Set-Variable NET_FW_IP_PROTOCOL_TCP 6 }
if (!(Test-Path variable:\NET_FW_IP_PROTOCOL_UDP)) { Set-Variable NET_FW_IP_PROTOCOL_UDP 17 }
if (!(Test-Path variable:\NET_FW_PROFILE_DOMAIN))  { Set-Variable NET_FW_PROFILE_DOMAIN  0x1 }
if (!(Test-Path variable:\NET_FW_PROFILE_PRIVATE)) { Set-Variable NET_FW_PROFILE_PRIVATE 0x2 }
if (!(Test-Path variable:\NET_FW_PROFILE_PUBLIC))  { Set-Variable NET_FW_PROFILE_PUBLIC  0x2 }
if (!(Test-Path variable:\NET_FW_PROFILE_ALL))     { Set-Variable NET_FW_PROFILE_ALL     0x7FFFFFFF }

function Enable-FirewallRule([String] $name, [String] $description = "", [ScriptBlock] $filter = { $_.Name = $name }, [ScriptBlock] $createRule = {}) {
    <#
        .SYNOPSIS
        
        Creates or enables a firewall rule

        .DESCRIPTION
        
        The Enable-FirewallRule function checks whether a given firewall rule exists, and if
        it does, it enables it, if it is not already enabled. If the rule does not exist,
        it is created, calling the $createRule script block to finalize the rule

        .PARAMETER name

        the name of the rule

        .PARAMETER description
  
        a description for the firewall rule

        .PARAMETER filter

        a ScriptBlock to be passed to Where-Object to determine whether or not the rule
        exists.

        .PARAMETER createRule

        a ScriptBlock that is called when the rule is created to allow the caller to specify
        any additional restrictions on the rule

        .EXAMPLE

        Create a rule that opens local port 8080 to all computers

        Enable-FirewallRule "Enable TCP Over Port 8080" -filter { $_.Enabled -And $_.LocalPorts -And $_.LocalPorts -eq "8080" } -createRule { param($rule) $rule.Protocol = $NET_FW_IP_PROTOCOL_TCP; $rule.LocalPorts = "8080" }"

        .EXAMPLE

        Create a rule that allows all incoming connections to notepad.exe

        Enable-FirewallRule "Enable Incoming TCP Connections to Notepad.exe" -filter { $_.Enabled -And $_.ApplicationName -And $_.ApplicationName = ("{0}\System32\notepad.exe" -f $Env:windir) } -createRule { param($rule) $rule.Protocol = $NET_FW_IP_PROTOCOL_TCP; $rule.ApplicationName = ("{0}\System32\notepad.exe" -f $Env:windir) }
    #>
    $rules = @($policy.Rules | Where-Object $filter)
    if ($rules.Count -eq 0) {
        $rule = New-Object -com HNetCfg.FWRule
        $rule.Name = $name
        $rule.Description = $description
        $rule.Protocol = $NET_FW_IP_PROTOCOL_TCP
        if ($createRule -ne $null) { $createRule.Invoke($rule) }
        $rule.Enabled = $NET_FW_ENABLED
        $policy.Rules.Add($rule)
        
        Write-Host ("Created the rule ""{0}""" -f $rule.Name)
    } elseif (@($rules | Where-Object { $_.Enabled }).Count -eq 0) {
        $rules | Where-Object { !$_.Enabled } | Select-Object -f 1 | ForEach-Object { 
            $_.Enabled = $NET_FW_ENABLED
            Write-Host ("Enabled the rule ""{0}""" -f $_.Name)
        }
    } else {
        $rules | Where-Object { $_.Enabled } | ForEach-Object {
            Write-Host ("The rule ""{0}"" was already enabled" -f $_.Name)
        }
    }
}

function Disable-FirewallRules([ScriptBlock] $filter = {}) {
    <#
        .SYNOPSIS
        
        Disables a set of firewall rules matching the filter

        .DESCRIPTION
        
        The Disable-FirewallRules function disables all enabled rules that match the supplied filter ScriptBlock.

        .PARAMETER filter

        a ScriptBlock matching all the rules to disable

        .EXAMPLE

        Disable all rules for incoming port 80 connections

        Disable-FirewallRules { $_.LocalPorts -And $_.LocalPorts -eq "80" }
    #>
    $rules = @($policy.Rules | Where-Object $filter | Where-Object { $_.Enabled })
    $rules | ForEach-Object { Write-Host ("Disabling rule: ""{0}""" -f $_.Name); $_.Enabled = $NET_FW_DISABLED }
}

function Remove-FirewallRules([ScriptBlock] $filter = {}) {
    <#
        .SYNOPSIS
        
        Deletes a set of firewall rules matching the filter

        .DESCRIPTION
        
        The Remove-FirewallRules function removes all rules that match the supplied filter ScriptBlock.

        .PARAMETER filter

        a ScriptBlock matching all the rules to remove

        .EXAMPLE

        Remove all firewall rules in the "Mistake" group

        Remove-FirewallRules { $_.Grouping -And $_.Grouping -eq "Mistake" }
    #>
    $rules = @($policy.Rules | Where-Object $filter)
    if ($rules.Count -gt 0) {
        $rules | ForEach-Object { Write-Host ("Deleting rule: ""{0}""" -f $_.Name); $policy.Rules.Remove($_.Name) }
    } else {
        Write-Host "No rules matched the supplied filter"
    }
}

$policy = New-Object -com HNetCfg.FwPolicy2

This PowerPack is probably more thorough, but otherwise, I couldn't find any good documentation on using PowerShell to script firewall rules. Note that it's necessary to run the script with elevated permission for any of this to take effect.