[dpdk-dev] [PATCH 6/6] ipsec: reorder packet check for esp inbound

[Konstantin Ananyev]

Right now check for packet length and padding is done inside cop_prepare().
It makes sense to have all necessary checks in one place at early stage:
inside pkt_prepare().
That allows to simplify (and later hopefully) optimize cop_prepare() part.

Signed-off-by: Konstantin Ananyev <konstantin.anan...@intel.com>
---
 lib/librte_ipsec/esp_inb.c | 30 ++++++++++++++----------------
 1 file changed, 14 insertions(+), 16 deletions(-)

diff --git a/lib/librte_ipsec/esp_inb.c b/lib/librte_ipsec/esp_inb.c
index 562185ebe..d479af8ea 100644
--- a/lib/librte_ipsec/esp_inb.c
+++ b/lib/librte_ipsec/esp_inb.c
@@ -26,11 +26,6 @@ inb_cop_prepare(struct rte_crypto_op *cop,
        struct rte_crypto_sym_op *sop;
        struct aead_gcm_iv *gcm;
        uint64_t *ivc, *ivp;
-       uint32_t clen;
-
-       clen = plen - sa->ctp.cipher.length;
-       if ((int32_t)clen < 0 || (clen & (sa->pad_align - 1)) != 0)
-               return -EINVAL;
 
        /* fill sym op fields */
        sop = cop->sym;
@@ -38,7 +33,7 @@ inb_cop_prepare(struct rte_crypto_op *cop,
        /* AEAD (AES_GCM) case */
        if (sa->aad_len != 0) {
                sop->aead.data.offset = pofs + sa->ctp.cipher.offset;
-               sop->aead.data.length = clen;
+               sop->aead.data.length = plen - sa->ctp.cipher.length;
                sop->aead.digest.data = icv->va;
                sop->aead.digest.phys_addr = icv->pa;
                sop->aead.aad.data = icv->va + sa->icv_len;
@@ -53,7 +48,7 @@ inb_cop_prepare(struct rte_crypto_op *cop,
        /* CRYPT+AUTH case */
        } else {
                sop->cipher.data.offset = pofs + sa->ctp.cipher.offset;
-               sop->cipher.data.length = clen;
+               sop->cipher.data.length = plen - sa->ctp.cipher.length;
                sop->auth.data.offset = pofs + sa->ctp.auth.offset;
                sop->auth.data.length = plen - sa->ctp.auth.length;
                sop->auth.digest.data = icv->va;
@@ -101,7 +96,7 @@ inb_pkt_prepare(const struct rte_ipsec_sa *sa, const struct 
replay_sqn *rsn,
 {
        int32_t rc;
        uint64_t sqn;
-       uint32_t icv_ofs, plen;
+       uint32_t clen, icv_ofs, plen;
        struct rte_mbuf *ml;
        struct esp_hdr *esph;
 
@@ -128,6 +123,11 @@ inb_pkt_prepare(const struct rte_ipsec_sa *sa, const 
struct replay_sqn *rsn,
        ml = rte_pktmbuf_lastseg(mb);
        icv_ofs = ml->data_len - sa->icv_len + sa->sqh_len;
 
+       /* check that packet has a valid length */
+       clen = plen - sa->ctp.cipher.length;
+       if ((int32_t)clen < 0 || (clen & (sa->pad_align - 1)) != 0)
+               return -EBADMSG;
+
        /* we have to allocate space for AAD somewhere,
         * right now - just use free trailing space at the last segment.
         * Would probably be more convenient to reserve space for AAD
@@ -170,21 +170,19 @@ esp_inb_pkt_prepare(const struct rte_ipsec_session *ss, 
struct rte_mbuf *mb[],
                rc = inb_pkt_prepare(sa, rsn, mb[i], hl, &icv);
                if (rc >= 0) {
                        lksd_none_cop_prepare(cop[k], cs, mb[i]);
-                       rc = inb_cop_prepare(cop[k], sa, mb[i], &icv, hl, rc);
-               }
-
-               k += (rc == 0);
-               if (rc != 0) {
+                       inb_cop_prepare(cop[k], sa, mb[i], &icv, hl, rc);
+                       k++;
+               } else
                        dr[i - k] = i;
-                       rte_errno = -rc;
-               }
        }
 
        rsn_release(sa, rsn);
 
        /* copy not prepared mbufs beyond good ones */
-       if (k != num && k != 0)
+       if (k != num && k != 0) {
                mbuf_bad_move(mb, dr, num, num - k);
+               rte_errno = EBADMSG;
+       }
 
        return k;
 }
-- 
2.17.1