[PATCH v3 net-next 6/8] udp: flow dissector offload
From: Tom Herbert <hidden>
Date: 2017-09-28 21:48:52
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. Signed-off-by: Tom Herbert <redacted> --- include/linux/udp.h | 8 ++++++++ include/net/udp.h | 8 ++++++++ include/net/udp_tunnel.h | 8 ++++++++ net/ipv4/udp_offload.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ net/ipv4/udp_tunnel.c | 1 + net/ipv6/udp_offload.c | 16 ++++++++++++++++ 6 files changed, 89 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 c6b1c5d8d3c9..4867f329538c 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h@@ -176,6 +176,14 @@ 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(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 a744bb515455..fddf923ef433 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c@@ -335,11 +335,59 @@ 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(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(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) +{ + if (!static_key_false(&udp_encap_needed)) + return FLOW_DISSECT_RET_CONTINUE; + + 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 111b026e4f03..45b77f92d77d 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c@@ -80,11 +80,27 @@ 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(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) +{ + if (!static_key_false(&udp_encap_needed)) + return FLOW_DISSECT_RET_CONTINUE; + + 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