Hi Jelte and Daniel,
Based on my understanding currently there is no setting that controls the
cipher choices used by TLS version 1.3 connections but the default
value(HIGH:MEDIUM:+3DES:!aNULL) is used. So if I want to connect to Postgres
(eg. Postgres 14) with different TLS versions of customized ciphers instead of
default one like below:
eg.
TLS1.2 of ciphers
ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA:ECDHE-RSA-AES128-SHA:AES256-SHA:AES128-SHA
TLS1.3 of ciphers
TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256
For TLS1.2 connection, we can set the configuration in postgresql.conf as:
ssl_ciphers =
'ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-GCM-SHA256:ECDHE-RSA-AES256-SHA:ECDHE-RSA-AES128-SHA:AES256-SHA:AES128-SHA'
How can I achieve the value for TLS1.3? Do you mean I can set the Ciphersuites
in openssl.conf, then Postgres will pick up and use this value accordingly?
eg. I can run below command to set ciphersuites of TLS1.3 on my appliance:
openssl ciphers -ciphersuites TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256
then Postgres will use 'TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256" as
ciphers for TLS1.3 connection?
Thanks,
Erica Zhang
Original Email
Sender:"Jelte Fennema-Nio"< [email protected] >;
Sent Time:2024/6/12 16:51
To:"Erica Zhang"< [email protected] >;
Cc recipient:"Michael Paquier"< [email protected] >;"Peter Eisentraut"<
[email protected] >;"pgsql-hackers"< [email protected]
>;
Subject:Re: Re: Re: Add support to TLS 1.3 cipher suites and curves lists
On Wed, 12 Jun 2024 at 04:32, Erica Zhang wrote:
> There are certain government, financial and other enterprise organizations
that have very strict requirements about the encrypted communication and more
specifically about fine grained params like the TLS ciphers and curves that
they use. The default ones for those customers are not acceptable. Any products
that integrate Postgres and requires encrypted communication with the Postgres
would have to fulfil those requirements.
Yeah, I ran into such requirements before too. So I do think it makes
sense to have such a feature in Postgres.
> So if we can have this patch in the upcoming new major version, that means
Postgres users who have similar requirements can upgrade to PG17.
As Daniel mentioned you can already achieve the same using the
"Ciphersuites" directive in openssl.conf. Also you could of course
always disable TLSv1.3 support.
