[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20200525154633.GB22403@atlantis>
Date: Mon, 25 May 2020 17:46:33 +0200
From: Petr Vaněk <pv@...ello.cz>
To: Steffen Klassert <steffen.klassert@...unet.com>,
Herbert Xu <herbert@...dor.apana.org.au>,
"David S. Miller" <davem@...emloft.net>,
Jakub Kicinski <kuba@...nel.org>, netdev@...r.kernel.org,
linux-kernel@...r.kernel.org
Cc: Petr Vaněk <pv@...ello.cz>
Subject: [PATCH net-next] xfrm: no-anti-replay protection flag
RFC 4303 in section 3.3.3 suggests to disable anti-replay for manually
distributed ICVs.
This patch introduces new extra_flag XFRM_SA_XFLAG_NO_ANTI_REPLAY which
disables anti-replay for outbound packets if set. The flag is used only
in legacy and bmp code, because esn should not be negotiated if
anti-replay is disabled (see note in 3.3.3 section).
Signed-off-by: Petr Vaněk <pv@...ello.cz>
---
include/uapi/linux/xfrm.h | 1 +
net/xfrm/xfrm_replay.c | 12 ++++++++----
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/include/uapi/linux/xfrm.h b/include/uapi/linux/xfrm.h
index 5f3b9fec7b5f..4842b1ed49e9 100644
--- a/include/uapi/linux/xfrm.h
+++ b/include/uapi/linux/xfrm.h
@@ -387,6 +387,7 @@ struct xfrm_usersa_info {
};
#define XFRM_SA_XFLAG_DONT_ENCAP_DSCP 1
+#define XFRM_SA_XFLAG_NO_ANTI_REPLAY 2
struct xfrm_usersa_id {
xfrm_address_t daddr;
diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index 98943f8d01aa..1602843aa2ec 100644
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -89,7 +89,8 @@ static int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
XFRM_SKB_CB(skb)->seq.output.low = ++x->replay.oseq;
XFRM_SKB_CB(skb)->seq.output.hi = 0;
- if (unlikely(x->replay.oseq == 0)) {
+ if (unlikely(x->replay.oseq == 0) &&
+ !(x->props.extra_flags & XFRM_SA_XFLAG_NO_ANTI_REPLAY)) {
x->replay.oseq--;
xfrm_audit_state_replay_overflow(x, skb);
err = -EOVERFLOW;
@@ -168,7 +169,8 @@ static int xfrm_replay_overflow_bmp(struct xfrm_state *x, struct sk_buff *skb)
if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
XFRM_SKB_CB(skb)->seq.output.low = ++replay_esn->oseq;
XFRM_SKB_CB(skb)->seq.output.hi = 0;
- if (unlikely(replay_esn->oseq == 0)) {
+ if (unlikely(replay_esn->oseq == 0) &&
+ !(x->props.extra_flags & XFRM_SA_XFLAG_NO_ANTI_REPLAY)) {
replay_esn->oseq--;
xfrm_audit_state_replay_overflow(x, skb);
err = -EOVERFLOW;
@@ -572,7 +574,8 @@ static int xfrm_replay_overflow_offload(struct xfrm_state *x, struct sk_buff *sk
XFRM_SKB_CB(skb)->seq.output.hi = 0;
xo->seq.hi = 0;
- if (unlikely(oseq < x->replay.oseq)) {
+ if (unlikely(oseq < x->replay.oseq) &&
+ !(x->props.extra_flags & XFRM_SA_XFLAG_NO_ANTI_REPLAY)) {
xfrm_audit_state_replay_overflow(x, skb);
err = -EOVERFLOW;
@@ -611,7 +614,8 @@ static int xfrm_replay_overflow_offload_bmp(struct xfrm_state *x, struct sk_buff
XFRM_SKB_CB(skb)->seq.output.hi = 0;
xo->seq.hi = 0;
- if (unlikely(oseq < replay_esn->oseq)) {
+ if (unlikely(oseq < replay_esn->oseq) &&
+ !(x->props.extra_flags & XFRM_SA_XFLAG_NO_ANTI_REPLAY)) {
xfrm_audit_state_replay_overflow(x, skb);
err = -EOVERFLOW;
--
2.26.2
Powered by blists - more mailing lists