Proxy SSL and rejecting unwanted Client Authentication

Morning

I have a server configure for mTLS and I would like to be able to inspect the Client Certificate presented and reject if some criteria matches, preferably via Proxy SSL.

However from what I am seeing it looks like that the F5 LTM cannot see the handshake and therefore reject during negotiation. I am assuming that this is what is meant by application traffic, i.e non handshake traffic.

Is there a way I can keep client authentication on the backend server and still intercept the client SSL handshake so that I can perform a reject.

The reason is that I have a large number of clients out there that I need to do an IP check against based on details in the subjectdn of the client certificate. I.e I take a value from the dn and use it to lookup a value and reject if not valid.

I need to keep the client cert and pass it down to an AMQP instance as it is configured for client certificate authentication.

Could I for example generate a cert on the fly to pass through to the backend server? Or is there a better way to do this?

Nicholas