From ce00b504f19896604d60d121008b8a2df48ef114 Mon Sep 17 00:00:00 2001 From: Marcin Smoczynski Date: Thu, 31 Oct 2019 15:04:45 +0100 Subject: [PATCH] examples/ipsec-secgw: fix GCM IV length 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://tools.ietf.org/html/rfc4106 [2] NIST SP800-38D https://csrc.nist.gov/publications/detail/sp/800-38d/final Fixes: 0fbd75a99f ("cryptodev: move IV parameters to session") Cc: stable@dpdk.org Signed-off-by: Marcin Smoczynski Acked-by: Akhil Goyal --- examples/ipsec-secgw/sa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/examples/ipsec-secgw/sa.c b/examples/ipsec-secgw/sa.c index 4cb90857c7..a8dee342eb 100644 --- a/examples/ipsec-secgw/sa.c +++ b/examples/ipsec-secgw/sa.c @@ -985,7 +985,7 @@ sa_add_rules(struct sa_ctx *sa_ctx, const struct ipsec_sa entries[], if (sa->aead_algo == RTE_CRYPTO_AEAD_AES_GCM) { struct rte_ipsec_session *ips; - iv_length = 16; + iv_length = 12; sa_ctx->xf[idx].a.type = RTE_CRYPTO_SYM_XFORM_AEAD; sa_ctx->xf[idx].a.aead.algo = sa->aead_algo; -- 2.20.1