> -----Original Message-----
> From: Anoob Joseph <ano...@marvell.com>
> Sent: Tuesday, 19 May, 2020 11:40
> To: Dybkowski, AdamX <adamx.dybkow...@intel.com>; dev@dpdk.org;
> Trahe, Fiona <fiona.tr...@intel.com>; akhil.go...@nxp.com
> Cc: sta...@dpdk.org
> Subject: RE: [dpdk-dev] [PATCH] cryptodev: fix SHA-1 digest enum comment
>
> Hi Adam,
>
> Please see inline.
>
> Thanks,
> Anoob
>
> > -----Original Message-----
> > From: Dybkowski, AdamX <adamx.dybkow...@intel.com>
> > Sent: Tuesday, May 19, 2020 3:01 PM
> > To: Anoob Joseph <ano...@marvell.com>; dev@dpdk.org; Trahe, Fiona
> > <fiona.tr...@intel.com>; akhil.go...@nxp.com
> > Cc: sta...@dpdk.org
> > Subject: [EXT] RE: [dpdk-dev] [PATCH] cryptodev: fix SHA-1 digest enum
> > comment
> >
> > External Email
> >
> > ----------------------------------------------------------------------
> > Hi.
> > My answer below.
> >
> > Adam
> >
> > > -----Original Message-----
> > > From: Anoob Joseph <ano...@marvell.com>
> > > Sent: Tuesday, 19 May, 2020 07:54
> > > To: Dybkowski, AdamX <adamx.dybkow...@intel.com>; dev@dpdk.org;
> > > Trahe, Fiona <fiona.tr...@intel.com>; akhil.go...@nxp.com
> > > Cc: sta...@dpdk.org
> > > Subject: RE: [dpdk-dev] [PATCH] cryptodev: fix SHA-1 digest enum
> > > comment
> > >
> > > Hi Adam, Akhil,
> > >
> > > Please see inline.
> > >
> > > Thanks,
> > > Anoob
> > >
> > > > -----Original Message-----
> > > > From: dev <dev-boun...@dpdk.org> On Behalf Of Adam Dybkowski
> > > > Sent: Monday, May 18, 2020 7:54 PM
> > > > To: dev@dpdk.org; fiona.tr...@intel.com; akhil.go...@nxp.com
> > > > Cc: Adam Dybkowski <adamx.dybkow...@intel.com>; sta...@dpdk.org
> > > > Subject: [dpdk-dev] [PATCH] cryptodev: fix SHA-1 digest enum
> > > > comment
> > > >
> > > > This patch fixes improper SHA-1 digest size in the enum comment.
> > > >
> > > > Fixes: 1bd407fac80b ("cryptodev: extract symmetric operations")
> > > > Cc: sta...@dpdk.org
> > > >
> > > > Signed-off-by: Adam Dybkowski <adamx.dybkow...@intel.com>
> > > > ---
> > > > lib/librte_cryptodev/rte_crypto_sym.h | 4 ++--
> > > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/lib/librte_cryptodev/rte_crypto_sym.h
> > > > b/lib/librte_cryptodev/rte_crypto_sym.h
> > > > index d9585ecd6..9cea4e5f0 100644
> > > > --- a/lib/librte_cryptodev/rte_crypto_sym.h
> > > > +++ b/lib/librte_cryptodev/rte_crypto_sym.h
> > > > @@ -269,9 +269,9 @@ enum rte_crypto_auth_algorithm {
> > > > /**< HMAC using MD5 algorithm */
> > > >
> > > > RTE_CRYPTO_AUTH_SHA1,
> > > > - /**< 128 bit SHA algorithm. */
> > > > + /**< 160 bit SHA algorithm. */
> > > > RTE_CRYPTO_AUTH_SHA1_HMAC,
> > > > - /**< HMAC using 128 bit SHA algorithm. */
> > > > + /**< HMAC using 160 bit SHA algorithm. */
> > >
> > > [Anoob] This raises one interesting question. Is HMAC-SHA-1-96
> > > (https://urldefense.proofpoint.com/v2/url?u=https-3A__tools.ietf.org
> > > _h
> > >
> >
> tml_rfc2404&d=DwIFAg&c=nKjWec2b6R0mOyPaz7xtfQ&r=jPfB8rwwviRSxyL
> Ws2
> > n6B-
> >
> WYLn1v9SyTMrT5EQqh2TU&m=pgqB2BfFosCF_7l1SdoodgXcipf7G1ofht68ZK
> Mt
> > oW0&s=hxzUN2QfRJGaR7NQ7VKGm5oQvOZez6Z70mqOyg7gKTY&e= )
> treated as a
> > separate algorithm or is it a digest size variant of
> > RTE_CRYPTO_AUTH_SHA1_HMAC? I assume the later.
> >
> > [Adam] DPDK doesn't have separate enums for such variations. According
> > to RFC 2104, chapter "5. Truncated output", the calculation of
> > HMAC-SHA-1-96 is done using ordinary HMAC-SHA-1, but the calculation
> > result is then truncated to 96 bits, or any other digest size provided in
> > auth
> xform.
>
> [Anoob] So it is allowed to support digest sizes 12 & 20, right? Can you
> update the above comment in that case?
[Adam] This depends on a particular PMD and its capabilities so we cannot write
here in this public header file. For example, have a look in the capabilities
structure of QAT PMD:
{ /* SHA1 */ \
.op = RTE_CRYPTO_OP_TYPE_SYMMETRIC, \
{.sym = { \
.xform_type = RTE_CRYPTO_SYM_XFORM_AUTH, \
{.auth = { \
.algo = RTE_CRYPTO_AUTH_SHA1, \
.block_size = 64, \
.key_size = { \
.min = 0, \
.max = 0, \
.increment = 0 \
}, \
.digest_size = { \
.min = 1, \
.max = 20, \
.increment = 1 \
}, \
.iv_size = { 0 } \
}, } \
}, } \
}, \
It shows QAT PMD is able to truncate the output digest to any size from 1 to 20
bytes (160 bits).
This can be different in other PMDs, for example OpenSSL and CCP PMDs allow
only 20-byte digests here while Marvell MVSAM allows 12-20 bytes.
Adam
