Re: Tcrypt hmac(crc32) test can work only on Blackfin

On Thu, Nov 22, 2012 at 03:38:45AM -0500, Zhang, Sonic wrote:

quoted

On Wed, Nov 21, 2012 at 01:01:49PM +0100, Milan Broz wrote:

quoted

On 11/21/2012 12:29 PM, Zhang, Sonic wrote:

quoted

Is there a policy that the CRC test vector in testmgr.h should
support all CRC drivers?
If so, I am fine to drop this test vector.

Question for Herbert...
But the problem I see is that it confuses people, it simply returns
fail everytime (except Blackfin platform).

My mail originates from bug report "tcrypt tests started failing", and
it was not obvious why (for people not familiar with tcrypt internals,
they just tried all test modes available).

We should just make a generic version of crc32 available.

Hi Herbert and Broz,

Unfortunately, after investigating the hardware manual of Blackfin CRC engine and the CRC algorithm, I have to say the Blackfin CRC driver can't use current crc32c test vector in testmgr.h. Blackfin CRC engine only supports big endian CRC algorithm, while current crypto crc32c driver uses little endian CRC algorithm. The big endian CRC digest is different from that of the little endian.

There are 2 solutions. One is to add a big endian crc32c test vector. The other is to keep the Blackfin specific test vector. However, neither meets Broz's expectation of a generic crc32 test vector.

Any idea?

I think we should just remove the blackfin crc driver altogether
as nothing in the kernel ever uses hmac(crc32).

Cheers,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt