Restricting SSL/TLS protocol versions on Dovecot 2.2.22

[Alexander Dalloz]

Am 29.07.2018 um 21:02 schrieb J Doe:
> Hello,
> 
> I have a question regarding SSL/TLS settings for Dovecot version 2.2.22.
> 
> In: 10-ssl.conf there are two parameters:
> 
>      ssl_protocols
>      ssl_cipher_list
> 
> ssl_protocols is commented with “SSL protocol to use” and ssl_cipher_list is commented with “SSL ciphers to use”.
> 
> If I want to disable SSLv3, for example, do I need to use both parameters or will disabling SSLv3 ciphers in
> ssl_cipher_list do the same thing ?
> 
> So is:
> 
>      ssl_cipher_list = !SSLv3
> 
> …equivalent to:
> 
>      ssl_protocols = !SSLv3
>      ssl_cipher_list = !SSLv3


No. SSLv3 is not a cipher but a protocol.

"ssl_protocols = !SSLv2 !SSLv3" is what you want to specify.

For ciphers you could define by ssl_cipher_list see "openssl ciphers -v"

> Thanks,
> 
> - J

Alexander