Retrieve Detailed Windows Network Information with PowerShell

# NetworkInfoDetailed.ps1 - Detailed network information for Windows

# Helper function: Convert a CIDR prefix (e.g. 24) to a dotted-decimal subnet mask (e.g. 255.255.255.0)
function Convert-PrefixToSubnetMask {
    param (
        [int]$PrefixLength
    )
    $max = [uint32]::MaxValue
    # For a given prefix, the netmask is: netmask = max - (2^(32 - prefix) - 1)
    $netmaskInt = $max - ([uint32]([math]::Pow(2, (32 - $PrefixLength)) - 1))
    $octet1 = ($netmaskInt -shr 24) -band 0xFF
    $octet2 = ($netmaskInt -shr 16) -band 0xFF
    $octet3 = ($netmaskInt -shr 8) -band 0xFF
    $octet4 = $netmaskInt -band 0xFF
    return "$octet1.$octet2.$octet3.$octet4"
}

# Helper function: Convert an IP string to a 32-bit unsigned integer.
function Convert-IPStringToInt {
    param ([string]$ip)
    $bytes = $ip.Split('.') | ForEach-Object { [uint32]$_ }
    return ([uint32]($bytes[0] -shl 24)) -bor ([uint32]($bytes[1] -shl 16)) -bor ([uint32]($bytes[2] -shl 8)) -bor $bytes[3]
}

# Helper function: Convert a 32-bit unsigned integer to an IP string.
function Convert-IntToIPAddress {
    param ([uint32]$ipInt)
    $a = ($ipInt -shr 24) -band 0xFF
    $b = ($ipInt -shr 16) -band 0xFF
    $c = ($ipInt -shr 8) -band 0xFF
    $d = $ipInt -band 0xFF
    return "$a.$b.$c.$d"
}

# Begin output with colored text using Write-Host.
Write-Host "Gathering default route information..." -ForegroundColor Blue

# Get the default route (DestinationPrefix "0.0.0.0/0") for IPv4.
$defaultRoute = Get-NetRoute -DestinationPrefix "0.0.0.0/0" -ErrorAction SilentlyContinue | 
    Where-Object { $_.NextHop -ne "0.0.0.0" } | 
    Sort-Object -Property RouteMetric | 
    Select-Object -First 1

if (-not $defaultRoute) {
    Write-Host "Error: No active network interface found. Are you connected to a network?" -ForegroundColor Red
    exit 1
}

$gateway    = $defaultRoute.NextHop
$ifaceIndex = $defaultRoute.InterfaceIndex

# Retrieve the network adapter based on InterfaceIndex.
$interface = Get-NetAdapter -InterfaceIndex $ifaceIndex -ErrorAction SilentlyContinue
if (-not $interface) {
    Write-Host "Error: Could not retrieve network adapter information." -ForegroundColor Red
    exit 1
}
$ifaceName = $interface.Name

Write-Host "Default Interface: $ifaceName" -ForegroundColor Green
Write-Host "Gateway: $gateway" -ForegroundColor Green

# Get the IPv4 address information.
$ipInfo = Get-NetIPAddress -InterfaceIndex $ifaceIndex -AddressFamily IPv4 -ErrorAction SilentlyContinue |
    Where-Object { $_.IPAddress } |
    Select-Object -First 1
if (-not $ipInfo) {
    Write-Host "Error: Could not retrieve IP address information." -ForegroundColor Red
    exit 1
}
$ip           = $ipInfo.IPAddress
$prefixLength = $ipInfo.PrefixLength

Write-Host "IP Address: $ip" -ForegroundColor Green

# Convert the prefix length to a subnet mask.
$netmask = Convert-PrefixToSubnetMask -PrefixLength $prefixLength
Write-Host "Subnet Mask: $netmask" -ForegroundColor Green

# Calculate the broadcast address.
$ipInt = Convert-IPStringToInt -ip $ip

$max = [uint32]::MaxValue
# Compute the netmask integer as: max - (2^(32 - prefix) - 1)
$netmaskInt = $max - ([uint32]([math]::Pow(2, (32 - $prefixLength)) - 1))
# The inverse mask (host portion) is:
$inv = $max - $netmaskInt

# Calculate the broadcast integer: (IP AND netmask) OR inverse mask.
$broadcastInt = ([uint32]($ipInt -band $netmaskInt)) -bor $inv

$broadcast = Convert-IntToIPAddress -ipInt $broadcastInt
Write-Host "Broadcast Address: $broadcast" -ForegroundColor Green

# Get the MAC (hardware) address.
$mac = $interface.MacAddress
Write-Host "MAC Address: $mac" -ForegroundColor Green

# Retrieve DNS servers for the interface.
$dnsInfo = Get-DnsClientServerAddress -InterfaceIndex $ifaceIndex -AddressFamily IPv4 -ErrorAction SilentlyContinue
$dnsServers = $dnsInfo.ServerAddresses -join ' '
Write-Host "DNS Servers: $dnsServers" -ForegroundColor Green

# Get the public IP address using an external service (api.ipify.org).
try {
    $public_ip = Invoke-RestMethod -Uri "https://api.ipify.org"
    Write-Host "Public IP Address: $public_ip" -ForegroundColor Green
} catch {
    Write-Host "Error retrieving public IP address." -ForegroundColor Red
}

# Perform a ping test to 8.8.8.8 and calculate the average latency.
Write-Host "Performing ping test to 8.8.8.8..." -ForegroundColor Blue
try {
    $pingResults = Test-Connection -ComputerName 8.8.8.8 -Count 3 -ErrorAction Stop
    if ($pingResults) {
        $avgLatency = ($pingResults | Measure-Object -Property ResponseTime -Average).Average
        Write-Host ("Average Latency (ping): {0:N2} ms" -f $avgLatency) -ForegroundColor Green
    } else {
        Write-Host "Ping test failed." -ForegroundColor Red
    }
} catch {
    Write-Host "Ping test failed." -ForegroundColor Red
}

Write-Host "Detailed network information gathered successfully." -ForegroundColor Blue