[PATCH net 14/17] ipvs: pass parsed transport offset to state handlers

[Florian Westphal <fw@strlen.de>]

From: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>

IPVS callers already parse the packet into struct ip_vs_iphdr before
updating connection state. For IPv6 this records the real
transport-header offset after extension headers in iph.len.

Pass this parsed transport offset through ip_vs_set_state() and the
protocol state_transition() callback so protocol handlers can use the
same packet context as scheduling and NAT handling. This patch only
changes the common callback plumbing and adapts the protocol callback
signatures; TCP and SCTP start using the value in follow-up patches.

Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Florian Westphal <fw@strlen.de>
---
 include/net/ip_vs.h                   |  3 ++-
 net/netfilter/ipvs/ip_vs_core.c       | 10 +++++-----
 net/netfilter/ipvs/ip_vs_proto_sctp.c |  3 ++-
 net/netfilter/ipvs/ip_vs_proto_tcp.c  |  3 ++-
 net/netfilter/ipvs/ip_vs_proto_udp.c  |  3 ++-
 5 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index 49297fec448a..417ff51f62fc 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -752,7 +752,8 @@ struct ip_vs_protocol {
 
 	void (*state_transition)(struct ip_vs_conn *cp, int direction,
 				 const struct sk_buff *skb,
-				 struct ip_vs_proto_data *pd);
+				 struct ip_vs_proto_data *pd,
+				 unsigned int iph_len);
 
 	int (*register_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc);
 
diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index 906f2c361676..f79c09869636 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -398,10 +398,10 @@ ip_vs_conn_stats(struct ip_vs_conn *cp, struct ip_vs_service *svc)
 static inline void
 ip_vs_set_state(struct ip_vs_conn *cp, int direction,
 		const struct sk_buff *skb,
-		struct ip_vs_proto_data *pd)
+		struct ip_vs_proto_data *pd, unsigned int iph_len)
 {
 	if (likely(pd->pp->state_transition))
-		pd->pp->state_transition(cp, direction, skb, pd);
+		pd->pp->state_transition(cp, direction, skb, pd, iph_len);
 }
 
 static inline int
@@ -803,7 +803,7 @@ int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
 		ip_vs_in_stats(cp, skb);
 
 		/* set state */
-		ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
+		ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd, iph->len);
 
 		/* transmit the first SYN packet */
 		ret = cp->packet_xmit(skb, cp, pd->pp, iph);
@@ -1484,7 +1484,7 @@ handle_response(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
 
 after_nat:
 	ip_vs_out_stats(cp, skb);
-	ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd);
+	ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd, iph->len);
 	skb->ipvs_property = 1;
 	if (!(cp->flags & IP_VS_CONN_F_NFCT))
 		ip_vs_notrack(skb);
@@ -2233,7 +2233,7 @@ ip_vs_in_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state
 	IP_VS_DBG_PKT(11, af, pp, skb, iph.off, "Incoming packet");
 
 	ip_vs_in_stats(cp, skb);
-	ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
+	ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd, iph.len);
 	if (cp->packet_xmit)
 		ret = cp->packet_xmit(skb, cp, pp, &iph);
 		/* do not touch skb anymore */
diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c
index 63c78a1f3918..394367b7b388 100644
--- a/net/netfilter/ipvs/ip_vs_proto_sctp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c
@@ -468,7 +468,8 @@ set_sctp_state(struct ip_vs_proto_data *pd, struct ip_vs_conn *cp,
 
 static void
 sctp_state_transition(struct ip_vs_conn *cp, int direction,
-		const struct sk_buff *skb, struct ip_vs_proto_data *pd)
+		const struct sk_buff *skb, struct ip_vs_proto_data *pd,
+		unsigned int iph_len)
 {
 	spin_lock_bh(&cp->lock);
 	set_sctp_state(pd, cp, direction, skb);
diff --git a/net/netfilter/ipvs/ip_vs_proto_tcp.c b/net/netfilter/ipvs/ip_vs_proto_tcp.c
index 8cc0a8ce6241..2d3f6aeafe52 100644
--- a/net/netfilter/ipvs/ip_vs_proto_tcp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_tcp.c
@@ -579,7 +579,8 @@ set_tcp_state(struct ip_vs_proto_data *pd, struct ip_vs_conn *cp,
 static void
 tcp_state_transition(struct ip_vs_conn *cp, int direction,
 		     const struct sk_buff *skb,
-		     struct ip_vs_proto_data *pd)
+		     struct ip_vs_proto_data *pd,
+		     unsigned int iph_len)
 {
 	struct tcphdr _tcph, *th;
 
diff --git a/net/netfilter/ipvs/ip_vs_proto_udp.c b/net/netfilter/ipvs/ip_vs_proto_udp.c
index f9de632e38cd..58f9e255927e 100644
--- a/net/netfilter/ipvs/ip_vs_proto_udp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_udp.c
@@ -444,7 +444,8 @@ static const char * udp_state_name(int state)
 static void
 udp_state_transition(struct ip_vs_conn *cp, int direction,
 		     const struct sk_buff *skb,
-		     struct ip_vs_proto_data *pd)
+		     struct ip_vs_proto_data *pd,
+		     unsigned int iph_len)
 {
 	if (unlikely(!pd)) {
 		pr_err("UDP no ns data\n");
-- 
2.54.0