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Zuke_254875's avatar
Zuke_254875
Icon for Altostratus rankAltostratus
Aug 29, 2018

SSL handshake failure during SSO

Both our production and non-production service desk applications use SSO.   User connects to application VIP, which redirects users to the SSO VIP on 443.   The F5 configuration for these two ...
application delivery
BIG-IP
certificate
LTM
security
Zuke's avatar
Zuke
Icon for Cirrostratus rankCirrostratus
Aug 31, 2018

Kevin, both situations result in a failure.

In both instances, the F5 is the server.

I asked the customer if he can change the ciphers on the application servers, since I'm not allowed to make a change to my F5 configuration. Here is the config of the parent clientssl profile showing the defined ciphers, which I believe don't match up with any ciphers in the client hello 

ltm profile client-ssl /Common/default_cert_clientssl_profile {
    app-service none
    cert /Common/default.crt
    cert-key-chain {
        default {
            cert /Common/default.crt
            key /Common/default.key
        }
    }
    chain none
    ciphers ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-SHA256:AES256-G
CM-SHA384:AES256-SHA256:!SHA1:!SSLv3:!TLSv1:!TLSv1_1
    defaults-from /Common/clientssl
    inherit-certkeychain true
    key /Common/default.key
    passphrase none
    renegotiation disabled
}

When I compare the ciphers allowed in the clientssl profile and what was sent in the Client Hello packet, it looks to me like there are no ciphers that both sides agree upon.

Client Hello:

  • TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
  • TLS_RSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256
  • TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256
  • TLS_DHE_RSA_WITH_AES_128_CBC_SHA256
  • TLS_DHE_DSS_WITH_AES_128_CBC_SHA256
  • TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
  • TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
  • TLS_RSA_WITH_AES_128_CBC_SHA
  • TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA
  • TLS_ECDH_RSA_WITH_AES_128_CBC_SHA
  • TLS_DHE_RSA_WITH_AES_128_CBC_SHA
  • TLS_DHE_DSS_WITH_AES_128_CBC_SHA
  • TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
  • TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
  • TLS_RSA_WITH_AES_128_GCM_SHA256
  • TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256
  • TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256
  • TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
  • TLS_DHE_DSS_WITH_AES_128_GCM_SHA256
  • TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA
  • TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA
  • TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA
  • TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA
  • TLS_EMPTY_RENEGOTIATION_INFO_SCSV

Client SSL profile:

  • ECDHE-RSA-AES256-GCM-SHA384
  • ECDHE-ECDSA-AES256-GCM-SHA384
  • ECDHE-RSA-AES256-SHA384
  • ECDHE-ECDSA-AES256-SHA384
  • DHE-RSA-AES256-GCM-SHA384
  • DHE-RSA-AES256-SHA256
  • AES256-GCM-SHA384:AES256-SHA256
  • !SHA1
  • !SSLv3
  • !TLSv1
  • !TLSv1_1