Re: [RFCv3 05/15] tcp: authopt: Add crypto initialization

[Herbert Xu]

On Tue, Aug 24, 2021 at 04:34:58PM -0700, Eric Dumazet wrote:
> 
> On 8/24/21 2:34 PM, Leonard Crestez wrote:
> > The crypto_shash API is used in order to compute packet signatures. The
> > API comes with several unfortunate limitations:
> > 
> > 1) Allocating a crypto_shash can sleep and must be done in user context.
> > 2) Packet signatures must be computed in softirq context
> > 3) Packet signatures use dynamic "traffic keys" which require exclusive
> > access to crypto_shash for crypto_setkey.
> > 
> > The solution is to allocate one crypto_shash for each possible cpu for
> > each algorithm at setsockopt time. The per-cpu tfm is then borrowed from
> > softirq context, signatures are computed and the tfm is returned.
> > 
> 
> I could not see the per-cpu stuff that you mention in the changelog.

Perhaps it's time we moved the key information from the tfm into
the request structure for hashes? Or at least provide a way for
the key to be in the request structure in addition to the tfm as
the tfm model still works for IPsec.  Ard/Eric, what do you think
about that?

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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