Disable RC4 DES/3DES in HAproxy

keyser

Hi

I'm doing a bit of hardening of my HAproxy reverse proxy and have already disabled SSLv3 with the no-sslv3 statement in the advanced SSL frontend config.

But how do I disable the RC4 and DES/3DES ciphers on the proxy? I can't find any references on how to do that in the advances SSL frontend config.

Thanks

PiBa

With setting the 'ciphers' you can select to only allow ciphers that dont have rc4 des/3des.

p.s. might be useful: https://mozilla.github.io/server-side-tls/ssl-config-generator/

Kerat

in case anyone else has trouble there is two ways to do this. the first is from the front end the alternative is globally.
1. front end - edit - advanced settings - advanced pass thru
2. settings - Global Advanced pass through - custom options

I also have a rule in my global advanced pass through settings to explicitly deny SSL 3.0 and TLS1.0.

ssl-default-bind-options no-sslv3 no-tlsv10

even with that I was not getting good results when I would scan my subdomains using https://www.ssllabs.com/ssltest. it noted many deprecated ciphers were in use. I found some posts by others who were doing something close to what i wanted to do.
Ex: http://wolfspyre.com/?p=207

This was close but I still found that I was having trouble with the 3DES cipher on TLS 1.1 and 1.2.

https://www.ssllabs.com/ssltest, directed me to use the cipher list that mozilla outlined (https://wiki.mozilla.org/Security/Server_Side_TLS#Recommended_configurations). Because all of my remote devices are newer i opted to use the Modern cipher assortment. I added a lin underneath my default bind options eliminating support for SSL 3.0 and TLS1.0. it is the following:

ssl-default-bind-ciphers ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256

Currently, these ciphers seem to rule out TLS 1.0 and force TLS1.2 only. This could be a problem for older browsers and smart devices. SSLLabs' ssltest does a pretty good job of enumerating which systems are likely to have trouble. I have confirmed that all my devices work without issue given my configuration.