Forum Discussion

warbie's avatar
warbie
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Feb 10, 2020

Cipher Rule for just for TLS1.3

I'm running 15.0.1 on a pair for 2000s and I was trying to put a Cipher rule that just encompassed TLS1.3 so I can include with my other ciphers in a group. Seems like I can only do 1.3 with TLS13-AES128-GCM-SHA256 and TLS13-AES256-GCM-SHA384, but I can't seem to shave off all the other included ciphers with my attempts. I really feel like I'm doing this wrong. Our security team wants to depreciate TLS1.1 and lower and I just want to make sure we are looking forward until TLS1.3 becomes more widely used.

 

Please help.

Here is what I have: AES-GCM:!DHE:!ECDHE:!ADH:!SSLv3:!TLSv1:!TLSv1_1:!ADH:!DHE:!RC4:!DES:!3DES:!MD5:!SHA:!RSA+AES:!RSA

  • ECDH-RSA-AES128-GCM-SHA256/TLS1.2
  • ECDH-RSA-AES256-GCM-SHA384/TLS1.2
  • ECDHE-ECDSA-AES128-GCM-SHA256/TLS1.2
  • ECDHE-ECDSA-AES256-GCM-SHA384/TLS1.2
  • ECDH-ECDSA-AES128-GCM-SHA256/TLS1.2
  • ECDH-ECDSA-AES256-GCM-SHA384/TLS1.2
  • DHE-DSS-AES128-GCM-SHA256/TLS1.2
  • DHE-DSS-AES256-GCM-SHA384/TLS1.2
  • TLS13-AES128-GCM-SHA256/TLS1.3
  • TLS13-AES256-GCM-SHA384/TLS1.3

 

 

 

  • ltm cipher rule mozilla_modern_cipher_rule_v14 {

      cipher TLSv1_3

      dh-groups DEFAULT

      signature-algorithms DEFAULT

    }

     

    This works for me in BIG-IP 14.1.x

  • Smithy's avatar
    Smithy
    Icon for Cirrostratus rankCirrostratus

    ltm cipher rule mozilla_modern_cipher_rule_v14 {

      cipher TLSv1_3

      dh-groups DEFAULT

      signature-algorithms DEFAULT

    }

     

    This works for me in BIG-IP 14.1.x

  • warbie's avatar
    warbie
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    Brett I'm rather embarrassed that I didn't try that. Thanks! You are awesome!

  • wlopez's avatar
    wlopez
    Icon for Cirrocumulus rankCirrocumulus

    I haven't tried v15 yet.

     

    But on v14.1, TLS 1.3 is not included by default on the client ssl profiles.

    When you create the profile you need to disable the default option named 'No TLSv1.3' from the option list.

    The combination of disabling that option and selecting the cipher group created with TLS1.3 is what actually activates the protocol on the client profile.

  • warbie's avatar
    warbie
    Icon for Nimbostratus rankNimbostratus

    Right. My issue was trying to make a cipher rule that I could add to a group that was just including the TLSV1_3 which Brett my attention to. Thanks wlopez.