Google Authenticator Verification iRule (TMOS v11.1+ optimized)

Problem this snippet solves: Hi Folks, the provided iRule contains a TMOS v11.1+ compatible fork of the already existing and very lovely Google Authenticator verification iRules here on CodeShare....
Updated Jun 06, 2023
Version 2.0
application delivery
base32
BIG-IP Access Policy Manager (APM)
google authenticator
hmac
LTM
security
totp
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My name is Kai Wilke and I'm working as a Principal Consultant for IT-Security at itacs GmbH - a German consulting company specialized in Microsoft Security cloud solutions, F5 customizations as well as for classic IT-Consulting. You can find additional information about me and my work here: https://devcentral.f5.com/articles/q-a-with-itacs-gmbhs-kai-wilke-devcentrals-featured-member-for-february-24890
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Kai_Wilke
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Oct 31, 2016

Hi Stanislas,

Performance wise its better to use three tailordered code blocks. The problem of using cascaded for/foreach loops is, that you can't easily 

break
further execution within the inner loop once a match is found. You have to use a variable to maintain the result and you need to check this variable on each subsequent iteration.

Usability wise its up to you. Personally I think that using three times a slightly modified code is slightly easier to understand than a cascaded for/foreach loop. But mileage may vary... šŸ˜‰

Cheers, Kai