Re: [PATCH BlueZ] mesh: test AEAD at startup to check kernel support

On Fri, 2019-08-30 at 20:23 +0200, Michał Lowas-Rzechonek wrote:

Brian,

On 08/30, Brian Gix wrote:

quoted

One time test at startup to ensure either kernel version v4.9 or later,
*or* that required AES-CCM support has been back-ported. If support not
there, daemon will run without providing D-Bus service or attaching to
controllers (prevents systemd thrashing).

By the way - I have a patch that implements all required cryptographic
operations using libcrypto, enabled by ./configure --with-openssl
(disabled by default).

I know that last time we've talked about this, the consensus was that the
vendor should patch meshd to work on older kernels, so we did exactly
that - but maybe having this available in the mainline would be
interesting?

Yeah, we have talked internally about how much "old kernel support" cruft can be removed, which is one of the
things Marcel would want before doing a "Major Version Number Release" like "BlueZ-6.0", where we could say
that v6.0 requires a minimum kernel version of v4.9 or something...  As opposed to a minor version release like
"BlueZ-5.51" which has support for most v4.X kernels.  Perhaps something like openssl could be *suggested* in a
README as one of a few possible work-arounds a vendor could use to run on an older kernel, but there is no
support for adding an openssl dependancy into the BlueZ mainline tip.