Re: [PATCH v2] sctp: Make hmac algorithm selection for cookie generation dynamic

From: Vlad Yasevich <redacted>
Date: Thu, 25 Oct 2012 09:09:28 -0400

On 10/24/2012 03:20 PM, Neil Horman wrote:

quoted

Currently sctp allows for the optional use of md5 of sha1 hmac
algorithms to
generate cookie values when establishing new connections via two build
time
config options.  Theres no real reason to make this a static
selection.  We can
add a sysctl that allows for the dynamic selection of these algorithms
at run
time, with the default value determined by the corresponding crypto
library
availability.
This comes in handy when, for example running a system in FIPS mode,
where use
of md5 is disallowed, but SHA1 is permitted.

Note: This new sysctl has no corresponding socket option to select the
cookie
hmac algorithm.  I chose not to implement that intentionally, as RFC
6458
contains no option for this value, and I opted not to pollute the
socket option
namespace.

Change notes:
v2)
	* Updated subject to have the proper sctp prefix as per Dave M.
	* Replaced deafult selection options with new options that allow
	  developers to explicitly select available hmac algs at build time
	  as per suggestion by Vlad Y.

Thanks Neil.  That's much better.

Acked-by: Vlad Yasevich <redacted>

Applied.