Re: disabling certain ciphers

[Reindl Harald]

Am 02.12.2014 um 17:33 schrieb Darren Pilgrim:

On 12/2/2014 1:32 AM, Reindl Harald wrote:

ssl_cipher_list = HIGH:!RC4:!MD5:!SRP:!PSK:!aNULL:@STRENGTH
ssl_dh_parameters_length = 2048
ssl_parameters_regenerate = 0
ssl_protocols = !SSLv2 !SSLv3 TLSv1 TLSv1.1 TLSv1.2

But why does ssl_protocols behave differently depending on if
$ssl_cipher_list is defined? Shouldn't !SSLv2 and !SSLv3 be sufficient?

It seems that if ssl_cipher_list is defined,
ssl_protocols = !SSLv2 !SSLv3

results in TLS1.2 being the only one active, but if it is defined, 1.0,
1.1, and 1.2 are all active?

ssl_protocols = !SSLv2 !SSLv3

and you are fine, aynthing else is nonsense because when TLSv1.3 will be
released you go to each and every server to add it to the config? likely
not!

Configuration management. :)

mis-management is the right word for disable future procotols

Also, no, you need to do more than just disable SSLv3.  You need to
disable several cipher groups allowed in TLSv1.0 and TLSv1.1, bump up
the DH parameter size, and, if your client base allows it, only allow
ciphers with forward secrecy

i *only* referred to "ssl_protocols" and not to ciphers



ssl_protocols = !SSLv2 !SSLv3
ssl_prefer_server_ciphers = yes
ssl_options = no_compression

that below are sane settings supporting older Outlooks only talking RC4/DES but prefer a specific order for other clients ssl_cipher_list = ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA:AES256-SHA:DHE-RSA-CAMELLIA128-SHA:DHE-RSA-CAMELLIA256-SHA:CAMELLIA128-SHA:CAMELLIA256-SHA:ECDHE-RSA-DES-CBC3-SHA:DES-CBC3-SHA

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