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The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: This explains that 2.6 will ignore --cipher without --compat-mode and restructures the whole paragraph to better readable. Patch V2: Adjust grammar, use consistently "and later" Signed-off-by: Arne Schwabe --- doc/man-sections/cipher-negotiation.rst | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) Content analysis details: (0.3 points, 6.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.2 HEADER_FROM_DIFFERENT_DOMAINS From and EnvelopeFrom 2nd level mail domains are different 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 SPF_NONE SPF: sender does not publish an SPF Record X-Headers-End: 1mwnCp-00EFST-OE Subject: [Openvpn-devel] [PATCH v2] Adjust cipher-negotiation.rst with compat-mode changes X-BeenThere: openvpn-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: openvpn-devel-bounces@lists.sourceforge.net X-getmail-retrieved-from-mailbox: Inbox This explains that 2.6 will ignore --cipher without --compat-mode and restructures the whole paragraph to better readable. Patch V2: Adjust grammar, use consistently "and later" Signed-off-by: Arne Schwabe Acked-By: Frank Lichtenheld --- doc/man-sections/cipher-negotiation.rst | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/doc/man-sections/cipher-negotiation.rst b/doc/man-sections/cipher-negotiation.rst index 423b5ab6a..efa4c6c94 100644 --- a/doc/man-sections/cipher-negotiation.rst +++ b/doc/man-sections/cipher-negotiation.rst @@ -5,7 +5,7 @@ OpenVPN 2.4 and higher have the capability to negotiate the data cipher that is used to encrypt data packets. This section describes the mechanism in more detail and the different backwards compatibility mechanism with older server and clients. -OpenVPN 2.5 and higher behaviour +OpenVPN 2.5 and later behaviour -------------------------------- When both client and server are at least running OpenVPN 2.5, that the order of the ciphers of the server's ``--data-ciphers`` is used to pick the the data cipher. @@ -15,12 +15,15 @@ with a AUTH_FAILED message (as seen in client log): AUTH: Received control message: AUTH_FAILED,Data channel cipher negotiation failed (no shared cipher) -OpenVPN 2.5 will only allow the ciphers specified in ``--data-ciphers``. To ensure -backwards compatibility also if a cipher is specified using the ``--cipher`` option -it is automatically added to this list. If both options are unset the default is -:code:`AES-256-GCM:AES-128-GCM`. In 2.6 and later the default is changed to +OpenVPN 2.5 and later will only allow the ciphers specified in ``--data-ciphers``. + If ``--data-ciphers`` is not set the default is :code:`AES-256-GCM:AES-128-GCM`. +In 2.6 and later the default is changed to :code:`AES-256-GCM:AES-128-GCM:CHACHA20-POLY1305` when Chacha20-Poly1305 is available. +For backwards compatibility OpenVPN 2.6 and later with ``--compat-mode 2.4.x`` +(or lower) and OpenVPN 2.5 will automatically add a cipher specified using the +``--cipher`` option to this list. + OpenVPN 2.4 clients ------------------- The negotiation support in OpenVPN 2.4 was the first iteration of the implementation