Commit 6d4201b1 authored by Jakub Sitnicki's avatar Jakub Sitnicki Committed by Alexei Starovoitov

udp6: Run SK_LOOKUP BPF program on socket lookup

Same as for udp4, let BPF program override the socket lookup result, by
selecting a receiving socket of its choice or failing the lookup, if no
connected UDP socket matched packet 4-tuple.
Suggested-by: default avatarMarek Majkowski <marek@cloudflare.com>
Signed-off-by: default avatarJakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-11-jakub@cloudflare.com
parent 2a08748c
......@@ -190,6 +190,31 @@ static struct sock *udp6_lib_lookup2(struct net *net,
return result;
}
static inline struct sock *udp6_lookup_run_bpf(struct net *net,
struct udp_table *udptable,
struct sk_buff *skb,
const struct in6_addr *saddr,
__be16 sport,
const struct in6_addr *daddr,
u16 hnum)
{
struct sock *sk, *reuse_sk;
bool no_reuseport;
if (udptable != &udp_table)
return NULL; /* only UDP is supported */
no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP,
saddr, sport, daddr, hnum, &sk);
if (no_reuseport || IS_ERR_OR_NULL(sk))
return sk;
reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
if (reuse_sk)
sk = reuse_sk;
return sk;
}
/* rcu_read_lock() must be held */
struct sock *__udp6_lib_lookup(struct net *net,
const struct in6_addr *saddr, __be16 sport,
......@@ -200,25 +225,42 @@ struct sock *__udp6_lib_lookup(struct net *net,
unsigned short hnum = ntohs(dport);
unsigned int hash2, slot2;
struct udp_hslot *hslot2;
struct sock *result;
struct sock *result, *sk;
hash2 = ipv6_portaddr_hash(net, daddr, hnum);
slot2 = hash2 & udptable->mask;
hslot2 = &udptable->hash2[slot2];
/* Lookup connected or non-wildcard sockets */
result = udp6_lib_lookup2(net, saddr, sport,
daddr, hnum, dif, sdif,
hslot2, skb);
if (!result) {
hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
slot2 = hash2 & udptable->mask;
if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
goto done;
/* Lookup redirect from BPF */
if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
sk = udp6_lookup_run_bpf(net, udptable, skb,
saddr, sport, daddr, hnum);
if (sk) {
result = sk;
goto done;
}
}
hslot2 = &udptable->hash2[slot2];
/* Got non-wildcard socket or error on first lookup */
if (result)
goto done;
result = udp6_lib_lookup2(net, saddr, sport,
&in6addr_any, hnum, dif, sdif,
hslot2, skb);
}
/* Lookup wildcard sockets */
hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
slot2 = hash2 & udptable->mask;
hslot2 = &udptable->hash2[slot2];
result = udp6_lib_lookup2(net, saddr, sport,
&in6addr_any, hnum, dif, sdif,
hslot2, skb);
done:
if (IS_ERR(result))
return NULL;
return result;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment