{IPv6,xfrm} Add ESN support for AH ingress part
This patch add esn support for AH input stage by attaching upper 32bits
sequence number right after packet payload as specified by RFC 4302.
Then the ICV value will guard upper 32bits sequence number as well when
packet going in.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 8929812..6c5f094 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -530,6 +530,10 @@
int nexthdr;
int nfrags;
int err = -ENOMEM;
+ int seqhi_len = 0;
+ __be32 *seqhi;
+ int sglists = 0;
+ struct scatterlist *seqhisg;
if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
goto out;
@@ -566,14 +570,22 @@
skb_push(skb, hdr_len);
- work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len);
+ if (x->props.flags & XFRM_STATE_ESN) {
+ sglists = 1;
+ seqhi_len = sizeof(*seqhi);
+ }
+
+ work_iph = ah_alloc_tmp(ahash, nfrags + sglists, hdr_len +
+ ahp->icv_trunc_len + seqhi_len);
if (!work_iph)
goto out;
- auth_data = ah_tmp_auth(work_iph, hdr_len);
- icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
+ auth_data = ah_tmp_auth((u8 *)work_iph, hdr_len);
+ seqhi = (__be32 *)(auth_data + ahp->icv_trunc_len);
+ icv = ah_tmp_icv(ahash, seqhi, seqhi_len);
req = ah_tmp_req(ahash, icv);
sg = ah_req_sg(ahash, req);
+ seqhisg = sg + nfrags;
memcpy(work_iph, ip6h, hdr_len);
memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
@@ -588,10 +600,16 @@
ip6h->flow_lbl[2] = 0;
ip6h->hop_limit = 0;
- sg_init_table(sg, nfrags);
- skb_to_sgvec(skb, sg, 0, skb->len);
+ sg_init_table(sg, nfrags + sglists);
+ skb_to_sgvec_nomark(skb, sg, 0, skb->len);
- ahash_request_set_crypt(req, sg, icv, skb->len);
+ if (x->props.flags & XFRM_STATE_ESN) {
+ /* Attach seqhi sg right after packet payload */
+ *seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
+ sg_set_buf(seqhisg, seqhi, seqhi_len);
+ }
+
+ ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len);
ahash_request_set_callback(req, 0, ah6_input_done, skb);
AH_SKB_CB(skb)->tmp = work_iph;