soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF

Expose socket options for setting a classic or extended BPF program
for use when selecting sockets in an SO_REUSEPORT group.  These options
can be used on the first socket to belong to a group before bind or
on any socket in the group after bind.

This change includes refactoring of the existing sk_filter code to
allow reuse of the existing BPF filter validation checks.

Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 6 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 6204b8992de4..56fcb55fda31 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -272,7 +272,7 @@ begin:
                                 struct sock *sk2;
                                 hash = udp6_ehashfn(net, daddr, hnum,
                                                     saddr, sport);
-                                sk2 = reuseport_select_sock(sk, hash);
+                                sk2 = reuseport_select_sock(sk, hash, NULL, 0);
                                 if (sk2) {
                                         result = sk2;
                                         goto found;
@@ -310,7 +310,8 @@ found:
 struct sock *__udp6_lib_lookup(struct net *net,
                                       const struct in6_addr *saddr, __be16 sport,
                                       const struct in6_addr *daddr, __be16 dport,
-                                      int dif, struct udp_table *udptable)
+                                      int dif, struct udp_table *udptable,
+                                      struct sk_buff *skb)
 {
         struct sock *sk, *result;
         struct hlist_nulls_node *node;
@@ -358,7 +359,8 @@ begin:
                                 struct sock *sk2;
                                 hash = udp6_ehashfn(net, daddr, hnum,
                                                     saddr, sport);
-                                sk2 = reuseport_select_sock(sk, hash);
+                                sk2 = reuseport_select_sock(sk, hash, skb,
+                                                        sizeof(struct udphdr));
                                 if (sk2) {
                                         result = sk2;
                                         goto found;
@@ -407,13 +409,13 @@ static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
                 return sk;
         return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
                                  &iph->daddr, dport, inet6_iif(skb),
-                                 udptable);
+                                 udptable, skb);
 }
 
 struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
                              const struct in6_addr *daddr, __be16 dport, int dif)
 {
-        return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
+        return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table, NULL);
 }
 EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 
@@ -580,7 +582,7 @@ void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         struct net *net = dev_net(skb->dev);
 
         sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
-                               inet6_iif(skb), udptable);
+                               inet6_iif(skb), udptable, skb);
         if (!sk) {
                 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
                                    ICMP6_MIB_INERRORS);