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Author EA
Recipients EA, christian.heimes
Date 2019-03-31.20:32:26
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Message-id <CABQAAG5dJeFt2Do8npb7z7dT1USuf9vJG37Eo0F6-xD6Qwq_6Q@mail.gmail.com>
In-reply-to <1554061578.65.0.735068349993.issue36484@roundup.psfhosted.org>
Content
Thanks. Just to clarify regarding your comment: "Applications shouldn't
modify the cipher suites any more.":
I use python to develop scripts for running experiments, which requires me
to simulate specific clients precisely including their TLS 1.3 ciphers
order.
As you know, TLS 1.3 can not have weak ciphers and only 3 or 4 secure ones
are permitted by design. But still the order should be accurate in
simulation experiment settings. This is different from ordinary
development. It is a bit disappointing that the developer can re-order the
weaker ones (in TLS 1.2) but not TLS 1.3.
However, thanks again for your reply.

On Sun, Mar 31, 2019 at 8:46 PM Christian Heimes <report@bugs.python.org>
wrote:

>
> Christian Heimes <lists@cheimes.de> added the comment:
>
> I don't have plans to implement cipher suite selection for TLS 1.3 any
> time soon, maybe not at all. TLS 1.3 changed cipher selection a lot, making
> the API more complicated. The signature algorithm and key agreement groups
> are handled as separate extensions, resulting in three additional APIs.
>
> Applications shouldn't modify the cipher suites any more. These days TLS
> libraries provide a good and safe selection of suites. Weak ciphers should
> be disabled by either a security update of the TLS library or system-wide
> settings.
>
> There is one workaround: You can influence connection parameters with an
> OpenSSL config file [1][2] by setting OPENSSL_CONF env var. OpenSSL parses
> the file only once, so you have to set it before you start Python.
>
> [1] https://www.openssl.org/docs/manmaster/man5/config.html
> [2] https://fedoraproject.org/wiki/Changes/CryptoPolicy
>
> ----------
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <https://bugs.python.org/issue36484>
> _______________________________________
>
History
Date User Action Args
2019-03-31 20:32:26EAsetrecipients: + EA, christian.heimes
2019-03-31 20:32:26EAlinkissue36484 messages
2019-03-31 20:32:26EAcreate