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Forum Discussion

nirobi03_194837's avatar
nirobi03_194837
Icon for Nimbostratus rankNimbostratus
Nov 24, 2015

Can I enforce a maximum character limit for APM user name?

I would like to limit the username field to no more than 7 characters to prevent users from accidently putting their username and password in the username field.

 

Is this possible?

 

If so, how?

 

If not, is there an alternative that will allow non-plain-text usernames? (I believe the username needs to be sent in plain text to our Domain Controllers??)

 

THANKS!!! Nick

 

application delivery
BIG-IP Access Policy Manager (APM)

2 Replies

  • cjunior's avatar
    cjunior
    Icon for Nacreous rankNacreous
    Nov 24, 2015

    Hi, I think that's weird you need, but, in a simple way you could add a script in logon.inc resource on advanced mode design to check this in client side:

    (Place it at the bottom before the tag )

    Just a tip. I hope it helps you.

    Regards.
  • Lucas_Thompson_'s avatar
    Lucas_Thompson_
    Historic F5 Account
    Nov 25, 2015

    With APM you can basically do anything because you can stick TCL anywhere you want. Here's how to do that:

     

    1. Go to VPE in your access policy
    2. Add (or edit) a logon page Policy Item.
    3. Add a branch rule
    4. Add whatever expression you want (it doesn't matter, we're going to edit it)
    5. Click the Advanced tab
    6. Use this expression: expr { [string length [mcget {session.logon.last.username}]] > 7 }

    The system evaluates that from the innermost square brackets out, like algebra. "string length" is TCL to grab the length of a string. "mcget" grabs a session variable from APD's cache (or sessiondb, depending). "expr" evaluates the expression mathematically.

     

    • expr { [string length [mcget {session.logon.last.username}]] > 7 }
    • expr { [string length "johndoe"] > 7 }
    • expr { 7 > 7 }
    • expr { 0 }
    • Result: FALSE