Thread (10 messages) flat view 10 messages, 3 authors, 2017-08-30
STALE3308d

Revision v1 of 3 in this series.

Revisions (3)
  1. v1 current
  2. v2 [diff vs current]
  3. v4 [diff vs current]

[PATCH net-next 4/6] udp: flow dissector offload

From: Tom Herbert <hidden>
Date: 2017-08-29 17:20:19
Subsystem: networking [general], the rest, user datagram protocol (udp) · Maintainers: "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn

Add support to perform UDP specific flow dissection. This is
primarily intended for dissecting encapsulated packets in UDP
encapsulation.

This patch adds a flow_dissect offload for UDP4 and UDP6. The backend
function performs a socket lookup and calls the flow_dissect function
if a socket is found.
---
 include/linux/udp.h      |  8 ++++++++
 include/net/udp.h        |  8 ++++++++
 include/net/udp_tunnel.h |  8 ++++++++
 net/ipv4/udp_offload.c   | 45 +++++++++++++++++++++++++++++++++++++++++++++
 net/ipv4/udp_tunnel.c    |  1 +
 net/ipv6/udp_offload.c   | 13 +++++++++++++
 6 files changed, 83 insertions(+)
diff --git a/include/linux/udp.h b/include/linux/udp.h
index eaea63bc79bb..2e90b189ef6a 100644
--- a/include/linux/udp.h
+++ b/include/linux/udp.h
@@ -79,6 +79,14 @@ struct udp_sock {
 	int			(*gro_complete)(struct sock *sk,
 						struct sk_buff *skb,
 						int nhoff);
+	/* Flow dissector function for a UDP socket */
+	enum flow_dissect_ret (*flow_dissect)(struct sock *sk,
+			const struct sk_buff *skb,
+			struct flow_dissector_key_control *key_control,
+			struct flow_dissector *flow_dissector,
+			void *target_container, void *data,
+			__be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+			int *p_hlen, unsigned int flags);
 
 	/* udp_recvmsg try to use this before splicing sk_receive_queue */
 	struct sk_buff_head	reader_queue ____cacheline_aligned_in_smp;
diff --git a/include/net/udp.h b/include/net/udp.h
index f3d1de6f0983..499e4faf8b14 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -174,6 +174,14 @@ struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb,
 				 struct udphdr *uh, udp_lookup_t lookup);
 int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);
 
+enum flow_dissect_ret udp_flow_dissect(const struct sk_buff *skb,
+			udp_lookup_t lookup,
+			struct flow_dissector_key_control *key_control,
+			struct flow_dissector *flow_dissector,
+			void *target_container, void *data,
+			__be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+			int *p_hlen, unsigned int flags);
+
 static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
 {
 	struct udphdr *uh;
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index 10cce0dd4450..b7102e0f41a9 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -69,6 +69,13 @@ typedef struct sk_buff **(*udp_tunnel_gro_receive_t)(struct sock *sk,
 						     struct sk_buff *skb);
 typedef int (*udp_tunnel_gro_complete_t)(struct sock *sk, struct sk_buff *skb,
 					 int nhoff);
+typedef enum flow_dissect_ret (*udp_tunnel_flow_dissect_t)(struct sock *sk,
+			const struct sk_buff *skb,
+			struct flow_dissector_key_control *key_control,
+			struct flow_dissector *flow_dissector,
+			void *target_container, void *data,
+			__be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+			int *p_hlen, unsigned int flags);
 
 struct udp_tunnel_sock_cfg {
 	void *sk_user_data;     /* user data used by encap_rcv call back */
@@ -78,6 +85,7 @@ struct udp_tunnel_sock_cfg {
 	udp_tunnel_encap_destroy_t encap_destroy;
 	udp_tunnel_gro_receive_t gro_receive;
 	udp_tunnel_gro_complete_t gro_complete;
+	udp_tunnel_flow_dissect_t flow_dissect;
 };
 
 /* Setup the given (UDP) sock to receive UDP encapsulated packets */
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 97658bfc1b58..7f0a7ed4a6f7 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -328,11 +328,56 @@ static int udp4_gro_complete(struct sk_buff *skb, int nhoff)
 	return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb);
 }
 
+enum flow_dissect_ret udp_flow_dissect(const struct sk_buff *skb,
+			udp_lookup_t lookup,
+			struct flow_dissector_key_control *key_control,
+			struct flow_dissector *flow_dissector,
+			void *target_container, void *data,
+			__be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+			int *p_hlen, unsigned int flags)
+{
+	enum flow_dissect_ret ret = FLOW_DISSECT_RET_CONTINUE;
+	struct udphdr *uh, _uh;
+	struct sock *sk;
+
+	uh = __skb_header_pointer(skb, *p_nhoff, sizeof(_uh), data,
+				  *p_hlen, &_uh);
+	if (!uh)
+		return FLOW_DISSECT_RET_OUT_BAD;
+
+	rcu_read_lock();
+
+	sk = (*lookup)(skb, uh->source, uh->dest);
+
+	if (sk && udp_sk(sk)->flow_dissect)
+		ret = udp_sk(sk)->flow_dissect(sk, skb, key_control,
+					       flow_dissector, target_container,
+					       data, p_proto, p_ip_proto,
+					       p_nhoff, p_hlen, flags);
+	rcu_read_unlock();
+
+	return ret;
+}
+EXPORT_SYMBOL(udp_flow_dissect);
+
+static enum flow_dissect_ret udp4_flow_dissect(const struct sk_buff *skb,
+			struct flow_dissector_key_control *key_control,
+			struct flow_dissector *flow_dissector,
+			void *target_container, void *data,
+			__be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+			int *p_hlen, unsigned int flags)
+{
+	return udp_flow_dissect(skb, udp4_lib_lookup_skb, key_control,
+				flow_dissector, target_container, data,
+				p_proto, p_ip_proto, p_nhoff, p_hlen, flags);
+}
+
 static const struct net_offload udpv4_offload = {
 	.callbacks = {
 		.gso_segment = udp4_tunnel_segment,
 		.gro_receive  =	udp4_gro_receive,
 		.gro_complete =	udp4_gro_complete,
+		.flow_dissect = udp4_flow_dissect,
 	},
 };
 
diff --git a/net/ipv4/udp_tunnel.c b/net/ipv4/udp_tunnel.c
index 6539ff15e9a3..a4eec2a044d2 100644
--- a/net/ipv4/udp_tunnel.c
+++ b/net/ipv4/udp_tunnel.c
@@ -71,6 +71,7 @@ void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 	udp_sk(sk)->encap_destroy = cfg->encap_destroy;
 	udp_sk(sk)->gro_receive = cfg->gro_receive;
 	udp_sk(sk)->gro_complete = cfg->gro_complete;
+	udp_sk(sk)->flow_dissect = cfg->flow_dissect;
 
 	udp_tunnel_encap_enable(sock);
 }
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 455fd4e39333..99ade504eaf7 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -73,11 +73,24 @@ static int udp6_gro_complete(struct sk_buff *skb, int nhoff)
 	return udp_gro_complete(skb, nhoff, udp6_lib_lookup_skb);
 }
 
+static enum flow_dissect_ret udp6_flow_dissect(const struct sk_buff *skb,
+			struct flow_dissector_key_control *key_control,
+			struct flow_dissector *flow_dissector,
+			void *target_container, void *data,
+			__be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+			int *p_hlen, unsigned int flags)
+{
+	return udp_flow_dissect(skb, udp6_lib_lookup_skb, key_control,
+				flow_dissector, target_container, data,
+				p_proto, p_ip_proto, p_nhoff, p_hlen, flags);
+}
+
 static const struct net_offload udpv6_offload = {
 	.callbacks = {
 		.gso_segment	=	udp6_tunnel_segment,
 		.gro_receive	=	udp6_gro_receive,
 		.gro_complete	=	udp6_gro_complete,
+		.flow_dissect	=	udp6_flow_dissect,
 	},
 };
 
-- 
2.11.0
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help