From d7f3f62167bc2299d9669888b493b6e6ba561c35 Mon Sep 17 00:00:00 2001 From: Benjamin LaHaise Date: Fri, 27 Apr 2012 08:24:08 +0000 Subject: [PATCH] net/ipv6/udp: UDP encapsulation: introduce encap_rcv hook into IPv6 Now that the sematics of udpv6_queue_rcv_skb() match IPv4's udp_queue_rcv_skb(), introduce the UDP encap_rcv() hook for IPv6. Signed-off-by: Benjamin LaHaise Signed-off-by: David S. Miller --- include/net/udp.h | 3 +++ net/ipv6/udp.c | 39 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+) diff --git a/include/net/udp.h b/include/net/udp.h index e66fc297b105..065f379c6503 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -268,4 +268,7 @@ extern int udp4_ufo_send_check(struct sk_buff *skb); extern struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, netdev_features_t features); extern void udp_encap_enable(void); +#if IS_ENABLED(CONFIG_IPV6) +extern void udpv6_encap_enable(void); +#endif #endif /* _UDP_H */ diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index bc533ea8fc68..c1d91a713e8e 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -525,6 +525,14 @@ static __inline__ void udpv6_err(struct sk_buff *skb, __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); } +static struct static_key udpv6_encap_needed __read_mostly; +void udpv6_encap_enable(void) +{ + if (!static_key_enabled(&udpv6_encap_needed)) + static_key_slow_inc(&udpv6_encap_needed); +} +EXPORT_SYMBOL(udpv6_encap_enable); + int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { struct udp_sock *up = udp_sk(sk); @@ -534,6 +542,37 @@ int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) goto drop; + if (static_key_false(&udpv6_encap_needed) && up->encap_type) { + int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); + + /* + * This is an encapsulation socket so pass the skb to + * the socket's udp_encap_rcv() hook. Otherwise, just + * fall through and pass this up the UDP socket. + * up->encap_rcv() returns the following value: + * =0 if skb was successfully passed to the encap + * handler or was discarded by it. + * >0 if skb should be passed on to UDP. + * <0 if skb should be resubmitted as proto -N + */ + + /* if we're overly short, let UDP handle it */ + encap_rcv = ACCESS_ONCE(up->encap_rcv); + if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) { + int ret; + + ret = encap_rcv(sk, skb); + if (ret <= 0) { + UDP_INC_STATS_BH(sock_net(sk), + UDP_MIB_INDATAGRAMS, + is_udplite); + return -ret; + } + } + + /* FALLTHROUGH -- it's a UDP Packet */ + } + /* * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). */ -- 2.20.1