[PATCH net-next v4 07/13] flow_dissector: Parse foo-over-udp (FOU)

[Tom Herbert <tom@herbertland.com>]

Parse FOU by getting the FOU protocol from the matching socket.
This includes moving "struct fou" and "fou_from_sock" to fou.h

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Tom Herbert <tom@herbertland.com>
---
 include/net/fou.h         | 16 ++++++++++++++++
 net/core/flow_dissector.c | 12 ++++++++++++
 net/ipv4/fou_core.c       | 16 ----------------
 3 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/include/net/fou.h b/include/net/fou.h
index 824eb4b231fd..8574767b91b6 100644
--- a/include/net/fou.h
+++ b/include/net/fou.h
@@ -17,6 +17,22 @@ int __fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
 int __gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
 		       u8 *protocol, __be16 *sport, int type);
 
+struct fou {
+	struct socket *sock;
+	u8 protocol;
+	u8 flags;
+	__be16 port;
+	u8 family;
+	u16 type;
+	struct list_head list;
+	struct rcu_head rcu;
+};
+
+static inline struct fou *fou_from_sock(struct sock *sk)
+{
+	return sk->sk_user_data;
+}
+
 int register_fou_bpf(void);
 
 #endif
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 49feea3fec56..e8760c1182b1 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -8,6 +8,7 @@
 #include <linux/filter.h>
 #include <net/dsa.h>
 #include <net/dst_metadata.h>
+#include <net/fou.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
 #include <net/gre.h>
@@ -855,6 +856,7 @@ __skb_flow_dissect_udp(const struct sk_buff *skb, const struct net *net,
 		       u8 *p_ip_proto, int base_nhoff, unsigned int flags,
 		       unsigned int num_hdrs)
 {
+	__u8 encap_type, fou_protocol;
 	enum flow_dissect_ret ret;
 	struct udphdr _udph;
 	int nhoff;
@@ -905,6 +907,9 @@ __skb_flow_dissect_udp(const struct sk_buff *skb, const struct net *net,
 		}
 
 		encap_type = udp_sk(sk)->encap_type;
+		if (encap_type == UDP_ENCAP_FOU)
+			fou_protocol = fou_from_sock(sk)->protocol;
+
 		rcu_read_unlock();
 
 		break;
@@ -943,6 +948,9 @@ __skb_flow_dissect_udp(const struct sk_buff *skb, const struct net *net,
 		}
 
 		encap_type = udp_sk(sk)->encap_type;
+		if (encap_type == UDP_ENCAP_FOU)
+			fou_protocol = fou_from_sock(sk)->protocol;
+
 		rcu_read_unlock();
 
 		break;
@@ -957,6 +965,10 @@ __skb_flow_dissect_udp(const struct sk_buff *skb, const struct net *net,
 	ret = FLOW_DISSECT_RET_OUT_GOOD;
 
 	switch (encap_type) {
+	case UDP_ENCAP_FOU:
+		*p_ip_proto = fou_protocol;
+		ret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
+		break;
 	case UDP_ENCAP_VXLAN:
 	case UDP_ENCAP_VXLAN_GPE:
 		ret = __skb_flow_dissect_vxlan(skb, flow_dissector,
diff --git a/net/ipv4/fou_core.c b/net/ipv4/fou_core.c
index 8241f762e45b..137eb80c56a2 100644
--- a/net/ipv4/fou_core.c
+++ b/net/ipv4/fou_core.c
@@ -21,17 +21,6 @@
 
 #include "fou_nl.h"
 
-struct fou {
-	struct socket *sock;
-	u8 protocol;
-	u8 flags;
-	__be16 port;
-	u8 family;
-	u16 type;
-	struct list_head list;
-	struct rcu_head rcu;
-};
-
 #define FOU_F_REMCSUM_NOPARTIAL BIT(0)
 
 struct fou_cfg {
@@ -48,11 +37,6 @@ struct fou_net {
 	struct mutex fou_lock;
 };
 
-static inline struct fou *fou_from_sock(struct sock *sk)
-{
-	return sk->sk_user_data;
-}
-
 static int fou_recv_pull(struct sk_buff *skb, struct fou *fou, size_t len)
 {
 	/* Remove 'len' bytes from the packet (UDP header and
-- 
2.34.1