Splunk Search

Is there a function to check if field is an ip address or hostname?

brdr
Contributor

I have a field to evaluate if the value of the field is an IP address or a hostname. if it is an IP address do something, if it is a hostname do something else.

Is there a eval function to check if field is IP or not?

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1 Solution

FrankVl
Ultra Champion

You can do something like this:

| eval fieldX = if(match(fieldX, "^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$"), "do something", "do something else")

See: http://docs.splunk.com/Documentation/Splunk/latest/SearchReference/ConditionalFunctions#match.28SUBJ...

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msquicc
Path Finder

here's what I landed on, in case it's helpful for folks in the future.  

 

| eval isIPV4 = if(match(IP,"^((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\b){4}$"),"True","False")

 

The best regex for validating IPV4 is an ever-evolving conversation on stack overflow.  So, I used the latest from there, but from this highest rated answer, not the accepted one: https://stackoverflow.com/a/36760050/6376311

 

Since someone mentioned it, in order to validate private/public IPv4, I made myself an eval-based macro with the following:

 

case(
cidrmatch("10.0.0.0/8",$IP$),"False",
cidrmatch("172.16.0.0/12",$IP$),"False",
cidrmatch("192.168.0.0/16",$IP$),"False",
isnull($IP$) OR like($IP$,""), "False",
match($IP$,"^((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\b){4}$"),"True")

 


Then, I can use it in any query like:

 

| eval Remote_Address_isExternal = `isExternalIPv4(Remote_Address)`

 

 

0 Karma

FrankVl
Ultra Champion

You can do something like this:

| eval fieldX = if(match(fieldX, "^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$"), "do something", "do something else")

See: http://docs.splunk.com/Documentation/Splunk/latest/SearchReference/ConditionalFunctions#match.28SUBJ...

brdr
Contributor

perfect. thanks!

0 Karma

Heff
Splunk Employee
Splunk Employee

Could you do something like this?
| eval isLocal=if(cidrmatch("10.0.0.0/24",ip), "local", "not local")

You could try 0.0.0.0/24 and see if that matches any IP address?
http://docs.splunk.com/Documentation/Splunk/latest/SearchReference/CommonEvalFunctions

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