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Maurice_G_'s avatar
Maurice_G_
Icon for Employee rankEmployee
Feb 16, 2007

require SSLv3 based on URI

I want to apply an iRule to a virtual server such that if the URI contains a certain string the SSLv2 cipher cannot be used.

 

How can I do this?

5 Replies

  • Colin_Walker_12's avatar
    Colin_Walker_12
    Historic F5 Account
    Unfortunately, since you'd have to decrypt the HTTP request to even see the URI that's being requested, you wouldn't be able to enforce a cipher choice based on URI, as the information would already be in plaintext by the time you'd have enough information to make this decision.

     

     

    Colin
  • bl0ndie_127134's avatar
    bl0ndie_127134
    Historic F5 Account
    SSL exposes a rule 'SSL::profile ' that allows you to select a particular SSL profile via the rules. You could try setting the profile to the restrictive one and call SSL::renogotiate. I have not tested to see if this works so you will have to try this out on your own.

     

     

    Alternatively you could just redirect the client to a VIP with the correct profile.
  • Thanks. I have an iRule associated with my VIP:80 which based on the URI selects a VIP:443 which has a profile which forbids SSLv2.

     

    Thanks again
  • I have an SSL profile which accepts even weak ciphers.

     

    Then I use an iRule to examine the encryption used and either let the request through if it is strong enough or just displays a page which lets the user know that a stronger cipher is needed to access the URL.
  • Yes this does work. You just need to apply an SSL profile which will accept ciphers < 128 bits long.

     

     

    -Al