Hi everyone, I've been trying to get PFS enabled on my LTM (ver 11.4.1) and am running into a blocker. I've tried various cipher string options and have no luck so far. I've also opened a ticket with f5 support and they just point me to various devcentral discussions that don't have the detail I need. So I guess my question is: what are the cipher options I need to add/remove to enable PFS on a SSL client profile? or is there another way to get PFS going that I am missing? Thanks!

So I guess my question is: what are the cipher options I need to add/remove to enable PFS on a SSL client profile? or is there another way to get PFS going that I am missing? i understand pfs is included since 11.2.1. you can display cipher suite list using tmm --clientciphers and tmm --serverciphers command. Diffie-Hellman SSL key exchange cipher The Diffie-Hellman SSL key exchange cipher, which provides perfect forward secrecy (PFS), is now included natively. This provides better performance for configurations using Diffie-Hellman, especially on physical platforms that have hardware SSL acceleration. Release Note: BIG-IP LTM and TMOS 11.2.1 https://support.f5.com/kb/en-us/products/big-ip_ltm/releasenotes/product/relnote-ltm-11-2-1.htmlrn_new

Thanks! Having read as much documentation as I can scrape up, I'm still trying to get SSL Labs to confirm PFS is enabled and am unsuccessful. Here's my cipher string: [root@lbl701:Active:In Sync] config tmm --serverciphers DEFAULT:@STRENGTH:-RC4 ID SUITE BITS PROT METHOD CIPHER MAC KEYX 0: 53 AES256-SHA 256 SSL3 Native AES SHA RSA 1: 53 AES256-SHA 256 TLS1 Native AES SHA RSA 2: 53 AES256-SHA 256 TLS1.1 Native AES SHA RSA 3: 53 AES256-SHA 256 TLS1.2 Native AES SHA RSA 4: 53 AES256-SHA 256 DTLS1 Native AES SHA RSA 5: 61 AES256-SHA256 256 TLS1.2 Native AES SHA256 RSA 6: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1 Native AES SHA ECDHE_RSA 7: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.1 Native AES SHA ECDHE_RSA 8: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.2 Native AES SHA ECDHE_RSA 9: 10 DES-CBC3-SHA 192 SSL3 Native DES SHA RSA 10: 10 DES-CBC3-SHA 192 TLS1 Native DES SHA RSA 11: 10 DES-CBC3-SHA 192 TLS1.1 Native DES SHA RSA 12: 10 DES-CBC3-SHA 192 TLS1.2 Native DES SHA RSA 13: 10 DES-CBC3-SHA 192 DTLS1 Native DES SHA RSA 14: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1 Native DES SHA ECDHE_RSA 15: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.1 Native DES SHA ECDHE_RSA 16: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.2 Native DES SHA ECDHE_RSA 17: 47 AES128-SHA 128 SSL3 Native AES SHA RSA 18: 47 AES128-SHA 128 TLS1 Native AES SHA RSA 19: 47 AES128-SHA 128 TLS1.1 Native AES SHA RSA 20: 47 AES128-SHA 128 TLS1.2 Native AES SHA RSA 21: 47 AES128-SHA 128 DTLS1 Native AES SHA RSA 22: 60 AES128-SHA256 128 TLS1.2 Native AES SHA256 RSA 23: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1 Native AES SHA ECDHE_RSA 24: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.1 Native AES SHA ECDHE_RSA 25: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.2 Native AES SHA ECDHE_RSA Do I need to disable all non-ECDHE to get this to work?

I'm still trying to get SSL Labs to confirm PFS is enabled and am unsuccessful. if you want pfs, why don't you specify only ECDHE (e.g. ECDHE)? by the way, isn't it clientcipher (clientssl profile)? [root@ve11a:Active:In Sync] config tmm --clientcipher ECDHE ID SUITE BITS PROT METHOD CIPHER MAC KEYX 0: 49200 ECDHE-RSA-AES256-GCM-SHA384 256 TLS1.2 Native AES-GCM SHA384 ECDHE_RSA 1: 49192 ECDHE-RSA-AES256-SHA384 256 TLS1.2 Native AES SHA384 ECDHE_RSA 2: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1 Native AES SHA ECDHE_RSA 3: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.1 Native AES SHA ECDHE_RSA 4: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.2 Native AES SHA ECDHE_RSA 5: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1 Native DES SHA ECDHE_RSA 6: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.1 Native DES SHA ECDHE_RSA 7: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.2 Native DES SHA ECDHE_RSA 8: 49199 ECDHE-RSA-AES128-GCM-SHA256 128 TLS1.2 Native AES-GCM SHA256 ECDHE_RSA 9: 49191 ECDHE-RSA-AES128-SHA256 128 TLS1.2 Native AES SHA256 ECDHE_RSA 10: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1 Native AES SHA ECDHE_RSA 11: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.1 Native AES SHA ECDHE_RSA 12: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.2 Native AES SHA ECDHE_RSA

Enabling PFS | DevCentral

53 Replies

nitass
Employee
Apr 18, 2014
I'm still trying to get SSL Labs to confirm PFS is enabled and am unsuccessful.

if you want pfs, why don't you specify only ECDHE (e.g. ECDHE)?

by the way, isn't it clientcipher (clientssl profile)?

[root@ve11a:Active:In Sync] config tmm --clientcipher ECDHE ID SUITE BITS PROT METHOD CIPHER MAC KEYX 0: 49200 ECDHE-RSA-AES256-GCM-SHA384 256 TLS1.2 Native AES-GCM SHA384 ECDHE_RSA 1: 49192 ECDHE-RSA-AES256-SHA384 256 TLS1.2 Native AES SHA384 ECDHE_RSA 2: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1 Native AES SHA ECDHE_RSA 3: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.1 Native AES SHA ECDHE_RSA 4: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.2 Native AES SHA ECDHE_RSA 5: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1 Native DES SHA ECDHE_RSA 6: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.1 Native DES SHA ECDHE_RSA 7: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.2 Native DES SHA ECDHE_RSA 8: 49199 ECDHE-RSA-AES128-GCM-SHA256 128 TLS1.2 Native AES-GCM SHA256 ECDHE_RSA 9: 49191 ECDHE-RSA-AES128-SHA256 128 TLS1.2 Native AES SHA256 ECDHE_RSA 10: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1 Native AES SHA ECDHE_RSA 11: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.1 Native AES SHA ECDHE_RSA 12: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.2 Native AES SHA ECDHE_RSA
- Steve_M__153836
  Nimbostratus
  Apr 27, 2015
  Check this out: https://www.chromium.org/Home/chromium-security/education/tlsTOC-Deprecation-of-TLS- Features-Algorithms-in-Chrome. ~~~ "Obsolete Cipher Suites You may see: “Your connection to example.com is encrypted with obsolete cryptography.” This means that the connection to the current website is using an outdated cipher suite (which Chrome still allows if the server insists on it). In order for the message to indicate “modern cryptography”, the connection should use the latest version of TLS with forward secrecy and a good (authenticated) cipher. As of mid-2015, the latest version of TLS is 1.2 and the only ciphers that Chrome considers modern are GCM or CHACHA20_POLY1305." ~~~ I think this is our answer. I don't want to only supply those ciphers. I think that's much, much too narrow. So A) does 11.4.1 support those ciphers (I'll see what I can find in the docs, should be easy to find) and what variables represent them in the cipher suite so I can prefer them (this I'm not so sure how to find)? EDIT: GCM is supported starting in 11.5.0 so I need to migrate to that (or more likely 11.5.2) before being able to test/resolve this warning. I have some lab VEs i fired up 11.5.2 on. I think this is probably the cipher suite order I would use to resolve the "obsolete cryptography", maintain support for PFS, and maintain enough available suites to satisfy a variety of browsers. AES-GCM+HIGH:ECDHE+HIGH:HIGH:@STRENGTH:!RSA:!SSLV3
- Steve_M__153836
  Nimbostratus
  Apr 27, 2015
  Some error in Chrome as earlier when I excluded SHA1. ERR_SSL_VERSION_OR_CIPHER_MISMATCH A secure connection cannot be established because this site uses an unsupported protocol.
- nitass
  Employee
  Apr 24, 2015
  it seems there are only 2 ciphers using sha256 in 11.4.1 hf7. would you like to try AES128-SHA256? [root@B4200-R77-S7:Active:Standalone] config tmm --clientciphers sha256 ID SUITE BITS PROT METHOD CIPHER MAC KEYX 0: 60 AES128-SHA256 128 TLS1.2 Native AES SHA256 RSA 1: 61 AES256-SHA256 256 TLS1.2 Native AES SHA256 RSA
nitass
Employee
Apr 18, 2014
So I guess my question is: what are the cipher options I need to add/remove to enable PFS on a SSL client profile? or is there another way to get PFS going that I am missing?

i understand pfs is included since 11.2.1. you can display cipher suite list using tmm --clientciphers and tmm --serverciphers command.

Diffie-Hellman SSL key exchange cipher The Diffie-Hellman SSL key exchange cipher, which provides perfect forward secrecy (PFS), is now included natively. This provides better performance for configurations using Diffie-Hellman, especially on physical platforms that have hardware SSL acceleration.

Release Note: BIG-IP LTM and TMOS 11.2.1

https://support.f5.com/kb/en-us/products/big-ip_ltm/releasenotes/product/relnote-ltm-11-2-1.htmlrn_new
- Sean_Gray_14855
  Nimbostratus
  Apr 18, 2014
  Thanks! Having read as much documentation as I can scrape up, I'm still trying to get SSL Labs to confirm PFS is enabled and am unsuccessful. Here's my cipher string: [root@lbl701:Active:In Sync] config tmm --serverciphers DEFAULT:@STRENGTH:-RC4 ID SUITE BITS PROT METHOD CIPHER MAC KEYX 0: 53 AES256-SHA 256 SSL3 Native AES SHA RSA 1: 53 AES256-SHA 256 TLS1 Native AES SHA RSA 2: 53 AES256-SHA 256 TLS1.1 Native AES SHA RSA 3: 53 AES256-SHA 256 TLS1.2 Native AES SHA RSA 4: 53 AES256-SHA 256 DTLS1 Native AES SHA RSA 5: 61 AES256-SHA256 256 TLS1.2 Native AES SHA256 RSA 6: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1 Native AES SHA ECDHE_RSA 7: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.1 Native AES SHA ECDHE_RSA 8: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.2 Native AES SHA ECDHE_RSA 9: 10 DES-CBC3-SHA 192 SSL3 Native DES SHA RSA 10: 10 DES-CBC3-SHA 192 TLS1 Native DES SHA RSA 11: 10 DES-CBC3-SHA 192 TLS1.1 Native DES SHA RSA 12: 10 DES-CBC3-SHA 192 TLS1.2 Native DES SHA RSA 13: 10 DES-CBC3-SHA 192 DTLS1 Native DES SHA RSA 14: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1 Native DES SHA ECDHE_RSA 15: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.1 Native DES SHA ECDHE_RSA 16: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.2 Native DES SHA ECDHE_RSA 17: 47 AES128-SHA 128 SSL3 Native AES SHA RSA 18: 47 AES128-SHA 128 TLS1 Native AES SHA RSA 19: 47 AES128-SHA 128 TLS1.1 Native AES SHA RSA 20: 47 AES128-SHA 128 TLS1.2 Native AES SHA RSA 21: 47 AES128-SHA 128 DTLS1 Native AES SHA RSA 22: 60 AES128-SHA256 128 TLS1.2 Native AES SHA256 RSA 23: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1 Native AES SHA ECDHE_RSA 24: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.1 Native AES SHA ECDHE_RSA 25: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.2 Native AES SHA ECDHE_RSA Do I need to disable all non-ECDHE to get this to work?
nitass_89166
Noctilucent
Apr 18, 2014
So I guess my question is: what are the cipher options I need to add/remove to enable PFS on a SSL client profile? or is there another way to get PFS going that I am missing?

i understand pfs is included since 11.2.1. you can display cipher suite list using tmm --clientciphers and tmm --serverciphers command.

Diffie-Hellman SSL key exchange cipher The Diffie-Hellman SSL key exchange cipher, which provides perfect forward secrecy (PFS), is now included natively. This provides better performance for configurations using Diffie-Hellman, especially on physical platforms that have hardware SSL acceleration.

Release Note: BIG-IP LTM and TMOS 11.2.1

https://support.f5.com/kb/en-us/products/big-ip_ltm/releasenotes/product/relnote-ltm-11-2-1.htmlrn_new
- Sean_Gray_14855
  Nimbostratus
  Apr 18, 2014
  Thanks! Having read as much documentation as I can scrape up, I'm still trying to get SSL Labs to confirm PFS is enabled and am unsuccessful. Here's my cipher string: [root@lbl701:Active:In Sync] config tmm --serverciphers DEFAULT:@STRENGTH:-RC4 ID SUITE BITS PROT METHOD CIPHER MAC KEYX 0: 53 AES256-SHA 256 SSL3 Native AES SHA RSA 1: 53 AES256-SHA 256 TLS1 Native AES SHA RSA 2: 53 AES256-SHA 256 TLS1.1 Native AES SHA RSA 3: 53 AES256-SHA 256 TLS1.2 Native AES SHA RSA 4: 53 AES256-SHA 256 DTLS1 Native AES SHA RSA 5: 61 AES256-SHA256 256 TLS1.2 Native AES SHA256 RSA 6: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1 Native AES SHA ECDHE_RSA 7: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.1 Native AES SHA ECDHE_RSA 8: 49172 ECDHE-RSA-AES256-CBC-SHA 256 TLS1.2 Native AES SHA ECDHE_RSA 9: 10 DES-CBC3-SHA 192 SSL3 Native DES SHA RSA 10: 10 DES-CBC3-SHA 192 TLS1 Native DES SHA RSA 11: 10 DES-CBC3-SHA 192 TLS1.1 Native DES SHA RSA 12: 10 DES-CBC3-SHA 192 TLS1.2 Native DES SHA RSA 13: 10 DES-CBC3-SHA 192 DTLS1 Native DES SHA RSA 14: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1 Native DES SHA ECDHE_RSA 15: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.1 Native DES SHA ECDHE_RSA 16: 49170 ECDHE-RSA-DES-CBC3-SHA 192 TLS1.2 Native DES SHA ECDHE_RSA 17: 47 AES128-SHA 128 SSL3 Native AES SHA RSA 18: 47 AES128-SHA 128 TLS1 Native AES SHA RSA 19: 47 AES128-SHA 128 TLS1.1 Native AES SHA RSA 20: 47 AES128-SHA 128 TLS1.2 Native AES SHA RSA 21: 47 AES128-SHA 128 DTLS1 Native AES SHA RSA 22: 60 AES128-SHA256 128 TLS1.2 Native AES SHA256 RSA 23: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1 Native AES SHA ECDHE_RSA 24: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.1 Native AES SHA ECDHE_RSA 25: 49171 ECDHE-RSA-AES128-CBC-SHA 128 TLS1.2 Native AES SHA ECDHE_RSA Do I need to disable all non-ECDHE to get this to work?