Re: [dpdk-stable] [PATCH] examples/ipsec-secgw: fix gcm iv length

[Akhil Goyal <akhil.goyal@nxp.com>]

> 
> The example IPsec application does not work properly when using
> AES-GCM with crypto_openssl.
> 
> ESP with AES-GCM uses standard 96bit long algorithm IV ([1]) which
> later concatenated with be32(1) forms a J0 block. GCM specification
> ([2], chapter 7.1) states that when length of IV is different than
> 96b, in order to format a J0 block, GHASH function must be used.
> 
> According to specification ([2], chapter 5.1.1) GCM implementations
> should support standard 96bit IVs, other lengths are optional. Every
> DPDK cryptodev supports 96bit IV and few of them supports 128bit
> IV as well (openssl, mrvl, ccp). When passing iv::length=16 to a
> cryptodev which does support standard IVs only (e.g. qat) it
> implicitly uses starting 96 bits. On the other hand, openssl follows
> specification and uses GHASH to compute J0 for that case which results
> in different than expected J0 values used for encryption/decryption.
> 
> Fix an inability to use AES-GCM with crypto_openssl by changing IV
> length to the standard value of 12.
> 
> [1] RFC4106, section "4. Nonce format" and "3.1. Initialization Vector"
> 
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftools.ietf
> .org%2Fhtml%2Frfc4106&data=02%7C01%7Cakhil.goyal%40nxp.com%7Cd
> 24096cff31845d1619e08d75e0babaa%7C686ea1d3bc2b4c6fa92cd99c5c301635
> %7C0%7C0%7C637081276526121698&sdata=DInvN3miogcG9WqkuRlUQ%
> 2BzuqMRs2P63CJA%2BojPx6vU%3D&reserved=0
> [2] NIST SP800-38D
> 
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcsrc.nist.
> gov%2Fpublications%2Fdetail%2Fsp%2F800-
> 38d%2Ffinal&data=02%7C01%7Cakhil.goyal%40nxp.com%7Cd24096cff318
> 45d1619e08d75e0babaa%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%
> 7C637081276526121698&sdata=EU6tJ9qvzpzh1b8j%2BsPjc18E3CUrXkSZ7c
> O6xvOmv1U%3D&reserved=0
> 
> Fixes: 0fbd75a99f ("cryptodev: move IV parameters to session")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Marcin Smoczynski <marcinx.smoczynski@intel.com>
> ---
Acked-by: Akhil Goyal <akhil.goyal@nxp.com>
Applied to dpdk-next-crypto

Thanks.