diff options
| author | Jakub Sitnicki <jakub@cloudflare.com> | 2020-07-17 12:35:31 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-07-18 05:18:17 +0200 |
| commit | 6d4201b1386b335bb53628a04ad63e547872dc5a (patch) | |
| tree | 0e70f7b235112512b6e9a2774e82899252550f4e /net/ipv6 | |
| parent | udp6: Extract helper for selecting socket from reuseport group (diff) | |
| download | linux-6d4201b1386b335bb53628a04ad63e547872dc5a.tar.xz linux-6d4201b1386b335bb53628a04ad63e547872dc5a.zip | |
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: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-11-jakub@cloudflare.com
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/udp.c | 60 |
1 files changed, 51 insertions, 9 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 084205c18a33..ff8be202726a 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -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; |