Parsing Netsh output - windows

Question

I need to parse the output given by the netsh command in powershell.
Below is the command i'm using
Netsh advfirewall show private
It's proving the below output
Private Profile Settings:
----------------------------------------------------------------------
State ON
Firewall Policy BlockInbound,AllowOutbound
LocalFirewallRules N/A (GPO-store only)
LocalConSecRules N/A (GPO-store only)
InboundUserNotification Enable
RemoteManagement Disable
UnicastResponseToMulticast Enable
Logging:
LogAllowedConnections Disable
LogDroppedConnections Disable
FileName %systemroot%\system32\LogFiles\Firewall\pfirewall.log
MaxFileSize 4096
My requirement is to access each and every value in the above output. Something like $result.state / $result.InboundUserNotification
I'm pretty new to PowerShell and i have searched on google about this and wasn't able to find anything.

Answer 1

The obligatory recommendation:
It's always better to find a PowerShell cmdlet to call, so you can take advantage of objects getting output, whose properties you can robustly access - but it sounds like the candidate cmdlet, Get-NetFirewallProfile doesn't work as expected for your use case (domain-joined computers).
Text parsing is always less robust than an object-based solution, though PowerShell offers many powerful features, if needed, notably in this case the switch statement with its -Regex option:
$result = [ordered] #{} # initialize the (ordered) result hashtable.
# Process each line output by netsh, and if it is a line
# containing a property/value-pair, add an entry to the hashtable.
switch -Regex (netsh advfirewall show private) {
'^(.+?) {2,}(.+)' { $result[$Matches.1] = $Matches.2 }
}
# Now you can access $result.State, $result.'Firewall Policy', ...
Note the assumption that the property name and its value are separated by at least two spaces
( {2,}); lines that don't match the property/value pattern are simply skipped.
An alternative is to assume a fixed column width with a single space separating the columns, which does seem to be the case here:
$result = [ordered] #{} # initialize the (ordered) result hashtable.
# Process each line output by netsh, and if it is a line
# containing a property/value-pair, add an entry to the hashtable.
switch -Regex (netsh advfirewall show private) {
'^(.{37}) (.+)' { $result[($Matches.1).TrimEnd()] = $Matches.2 }
}
Note the (...) (parentheses) around $Matches.1, which is unexpectedly required in order to call .TrimEnd() on the value; the parentheses wouldn't be necessary if index syntax ([1]) rather than property syntax .1 were used (that is, $Matches[1].TrimEnd() would work). The problem seems to be specific to property / key names that are numbers. See GitHub issue #14036

Answer 2

If you must parse this output, you can do the following:
$netsh = (Netsh advfirewall show private |
Select-String -Pattern "\s{2,}") -replace '\s{2,}','=' -replace '\\','\\' -join [System.Environment]::NewLine
$result = [pscustomobject](ConvertFrom-StringData $netsh)
The problem with the ConvertFrom-StringData method is the hash table output is not ordered. If order matters, you can just create your hash table by splitting each line into property/value pairs:
$hash = [ordered]#{}
Netsh advfirewall show private | Select-String -Pattern "\s{2,}" |
Foreach-Object {
$key,$value = $_ -split '\s{2,}'
$hash[$key] = $value
}
$result = [pscustomobject]$hash

Answer 3

Here's a similar approach to AdminOfThings answer utilizing ConvertFrom-StringData as well as Foreach-Object's -Begin and -End parameters.
Netsh advfirewall show private |
ForEach-Object -Begin{$ht = [ordered]#{}} {
if($_ -match '\s{10,}')
{
$ht += $_ -replace '\\','\\' -replace '\s{10,}','=' | ConvertFrom-StringData
}
} -End{[PSCustomObject]$ht} -OutVariable result
And a slight variation
Netsh advfirewall show private | Where-Object {$_ -match '\s{10,}'} |
ForEach-Object -Begin{$ht = [ordered]#{}} {
$ht += $_ -replace '\\','\\' -replace '\s{10,}','=' | ConvertFrom-StringData
} -End{[PSCustomObject]$ht} -OutVariable result