Message ID | 20120411022047.GA19124@kvack.org |
---|---|
State | Changes Requested, archived |
Delegated to: | David Miller |
Headers | show |
On 11/04/12 03:20, Benjamin LaHaise wrote: > At present, UDP encapsulated protocols (like L2TP) are only able to use the > encap_rcv hook with UDP over IPv4. This patch adds the same support for use > with UDP over IPv6. > > Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> Signed-off-by: James Chapman <jchapman@katalix.com> > --- > net/ipv6/udp.c | 31 +++++++++++++++++++++++++++++++ > 1 files changed, 31 insertions(+), 0 deletions(-) > > diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c > index 37b0699..4d7cd72 100644 > --- a/net/ipv6/udp.c > +++ b/net/ipv6/udp.c > @@ -515,6 +515,37 @@ int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) > if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) > goto drop; > > + if (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) { > + UDP6_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). > */
From: Benjamin LaHaise <bcrl@kvack.org> Date: Tue, 10 Apr 2012 22:20:47 -0400 > At present, UDP encapsulated protocols (like L2TP) are only able to use the > encap_rcv hook with UDP over IPv4. This patch adds the same support for use > with UDP over IPv6. > > Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> This isn't right at all. The return value of udpv6_queue_rcv_skb() ignorred at all call sites except when it is invoked via ->backlog_rcv(), which expects a different kind of return value, not an encap operation indication. So the whole "requeue as proto '-N'" logic isn't going to ever work. You need to do what the ipv4 side does, split the routine into two parts: 1) A __udpv6_queue_rcv_skb() which purely handles socket queueing cases. It does not handle encap or anything like that. This is what is what you hook into ->backlog_rcv for ipv6 udp. 2) A udpv6_queue_rcv_skb() which is invoked by the UDPv6 socket demux on receive, and which will properly propagate the return values back down into ipv6 input to do the "requeue as proto '-N'" stuff. Please resubmit both of these patches once you've fixed this up (and tested it). -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 37b0699..4d7cd72 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -515,6 +515,37 @@ int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) goto drop; + if (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) { + UDP6_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). */
At present, UDP encapsulated protocols (like L2TP) are only able to use the encap_rcv hook with UDP over IPv4. This patch adds the same support for use with UDP over IPv6. Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> --- net/ipv6/udp.c | 31 +++++++++++++++++++++++++++++++ 1 files changed, 31 insertions(+), 0 deletions(-)