How can I verify that a string is a valid IPv4 or IPv6 address in batch?

Question

I need to verify if a string is a valid IPv4 or IPv6 address in a Batch script, but apparently Batch doesn't have an easy way to parse an IP address.

How can I do this in Batch without using external tools? By "external tools" I mean things that aren't already present on a normal Windows installation.

By "valid IPv4 or IPv6 address" I mean a string that is in the format of an IP address, false positives with strings like 999.999.999.999 are OK (even if some basic filtering is welcome). As a rule of thumb, a solution should at least be able to distinguish an error message from an address.

I know that a similar question already exists, but that question doesn't take IPv6 into consideration and it's more strict in its definition of "valid IPv4 address" (something like 999.999.999.999 isn't acceptable).

Answer 1

Check for valid IPv4:

@if (@X)==(@Y) @end /* JScript comment     @echo off     cscript //E:JScript //nologo "%~f0"  %*     exit /b %errorlevel% @if (@X)==(@Y) @end JScript comment */ WScript.Quit(ValidateIPaddress(WScript.Arguments.Item(0))); function ValidateIPaddress(ipaddress) {  return !(/^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/.test(ipaddress)) } 

For valid IPv6 address:

@if (@X)==(@Y) @end /* JScript comment     @echo off     cscript //E:JScript //nologo "%~f0"  %*     exit /b %errorlevel% @if (@X)==(@Y) @end JScript comment */ WScript.Quit(ValidateIPaddress(WScript.Arguments.Item(0))); function ValidateIPaddress(ipaddress) {  return !(/(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))/gm.test(ipaddress)) } 

---

Both are relying on the exit code, so here's how they can be used:

call validIPV4.bat 12.12.12.12 && (    echo valid ipv4  ) || (    echo invalid ipv4 )  call validIPV4.bat 12.12.12.6000 && (   echo valid ipv4  ) || (   echo invalid ipv4 ) 

The first will print valid ipv4 the second invalid ipv4.

Or you can check the errorlevel:

call validIPV6.bat "1200:0000:AB00:1234:0000:2552:7777:1313" if %errorlevel% equ 0 (    echo valid ipv6  ) else (   echo invalid ipv6 )