xfrm: replay: remove advance indirection

Similar to other patches: add a new helper to avoid
an indirection.

v2: fix 'net/xfrm/xfrm_replay.c:519:13: warning: 'seq' may be used
uninitialized in this function' warning.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

include/net/xfrm.h

@@ -306,7 +306,6 @@ struct km_event {
 };
 
 struct xfrm_replay {
-	void	(*advance)(struct xfrm_state *x, __be32 net_seq);
 	int	(*check)(struct xfrm_state *x,
 			 struct sk_buff *skb,
 			 __be32 net_seq);
@@ -1722,6 +1721,7 @@ static inline int xfrm_policy_id2dir(u32 index)
 }
 
 #ifdef CONFIG_XFRM
+void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq);
 void xfrm_replay_notify(struct xfrm_state *x, int event);
 
 static inline int xfrm_aevent_is_on(struct net *net)

net/xfrm/xfrm_input.c

@@ -665,7 +665,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			goto drop_unlock;
 		}
 
-		x->repl->advance(x, seq);
+		xfrm_replay_advance(x, seq);
 
 		x->curlft.bytes += skb->len;
 		x->curlft.packets++;

net/xfrm/xfrm_replay.c

@@ -150,14 +150,26 @@ static int xfrm_replay_check(struct xfrm_state *x,
 	return -EINVAL;
 }
 
-static void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
+static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq);
+static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq);
+
+void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
 {
-	u32 diff;
-	u32 seq = ntohl(net_seq);
+	u32 diff, seq;
+
+	switch (x->repl_mode) {
+	case XFRM_REPLAY_MODE_LEGACY:
+		break;
+	case XFRM_REPLAY_MODE_BMP:
+		return xfrm_replay_advance_bmp(x, net_seq);
+	case XFRM_REPLAY_MODE_ESN:
+		return xfrm_replay_advance_esn(x, net_seq);
+	}
 
 	if (!x->props.replay_window)
 		return;
 
+	seq = ntohl(net_seq);
 	if (seq > x->replay.seq) {
 		diff = seq - x->replay.seq;
 		if (diff < x->props.replay_window)
@@ -695,42 +707,36 @@ static int xfrm_replay_overflow_offload_esn(struct xfrm_state *x, struct sk_buff
 }
 
 static const struct xfrm_replay xfrm_replay_legacy = {
-	.advance	= xfrm_replay_advance,
 	.check		= xfrm_replay_check,
 	.recheck	= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow_offload,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
-	.advance	= xfrm_replay_advance_bmp,
 	.check		= xfrm_replay_check_bmp,
 	.recheck	= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_offload_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
-	.advance	= xfrm_replay_advance_esn,
 	.check		= xfrm_replay_check_esn,
 	.recheck	= xfrm_replay_recheck_esn,
 	.overflow	= xfrm_replay_overflow_offload_esn,
 };
 #else
 static const struct xfrm_replay xfrm_replay_legacy = {
-	.advance	= xfrm_replay_advance,
 	.check		= xfrm_replay_check,
 	.recheck	= xfrm_replay_check,
 	.overflow	= xfrm_replay_overflow,
 };
 
 static const struct xfrm_replay xfrm_replay_bmp = {
-	.advance	= xfrm_replay_advance_bmp,
 	.check		= xfrm_replay_check_bmp,
 	.recheck	= xfrm_replay_check_bmp,
 	.overflow	= xfrm_replay_overflow_bmp,
 };
 
 static const struct xfrm_replay xfrm_replay_esn = {
-	.advance	= xfrm_replay_advance_esn,
 	.check		= xfrm_replay_check_esn,
 	.recheck	= xfrm_replay_recheck_esn,
 	.overflow	= xfrm_replay_overflow_esn,