classification
Title: SSL: Add client and server protocols for SSLContext
Type: enhancement Stage: patch review
Components: Extension Modules, SSL Versions: Python 3.7, Python 3.6
process
Status: open Resolution:
Dependencies: Superseder:
Assigned To: christian.heimes Nosy List: christian.heimes, python-dev
Priority: normal Keywords:

Created on 2016-09-11 21:54 by christian.heimes, last changed 2016-09-15 07:48 by christian.heimes.

Messages (3)
msg275862 - (view) Author: Christian Heimes (christian.heimes) * (Python committer) Date: 2016-09-11 21:54
In ticket #28022 and in thread https://mail.python.org/pipermail/python-dev/2016-September/146366.html I discussed two new protocols for SSLContext: PROTOCOL_TLS_CLIENT and PROTOCOL_TLS_SERVER. A SSLContext with PROTOCOL_TLS_CLIENT can only create connections to a server but cannot wrap server sockets. We can use it to have better defaults (e.g. cert validation and hostname verification for client side) and to make it impossible to confuse a server context with a client context. In the long run I'm planning to deprecate all but PROTOCOL_TLS_CLIENT and PROTOCOL_TLS_SERVER.

---
Finally (and this is the biggest) I like to change how the protocols
work. OpenSSL 1.1.0 has deprecated all version specific protocols. Soon
OpenSSL will only support auto-negotiation (formerly known as
PROTOCOL_SSLv23). My patch #26470 added PROTOCOL_TLS as alias for
PROTOCOL_SSLv23. If the last idea is accepted I will remove PROTOCOL_TLS
again. It hasn't been released yet. Instead I'm going to add
PROTOCOL_TLS_CLIENT and PROTOCOL_TLS_SERVER (see
https://www.openssl.org/docs/manmaster/ssl/SSL_CTX_new.html
TLS_server_method(), TLS_client_method()). PROTOCOL_TLS_CLIENT is like
PROTOCOL_SSLv23 but only supports client-side sockets and
PROTOCOL_TLS_SERVER just server-side sockets. In my experience we can't
have a SSLContext with sensible and secure settings for client and
server at the same time. Hostname checking and cert validation is only
sensible for client-side sockets.
---
msg275866 - (view) Author: Roundup Robot (python-dev) Date: 2016-09-11 22:02
New changeset 3ea641343244 by Christian Heimes in branch 'default':
Issue #28085: Add PROTOCOL_TLS_CLIENT and PROTOCOL_TLS_SERVER for SSLContext
https://hg.python.org/cpython/rev/3ea641343244
msg275871 - (view) Author: Christian Heimes (christian.heimes) * (Python committer) Date: 2016-09-11 22:09
I pushed basic support for PROTOCOL_TLS_CLIENT and PROTOCOL_TLS_SERVER in 3ea641343244. I have another patch that removes PROTOCOL_TLS again and changes create_default_context() to return either a server and client SSLContext. The change is a small possibility to break code that used the create_default_context() in a wrong way.
History
Date User Action Args
2016-09-15 07:48:54christian.heimessetcomponents: + SSL
2016-09-11 22:09:45christian.heimessetmessages: + msg275871
2016-09-11 22:02:01python-devsetnosy: + python-dev
messages: + msg275866
2016-09-11 21:54:39christian.heimescreate