bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jakub Sitnicki <jakub@cloudflare.com>
To: netdev@vger.kernel.org, bpf@vger.kernel.org
Cc: dccp@vger.kernel.org, kernel-team@cloudflare.com,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Gerrit Renker <gerrit@erg.abdn.ac.uk>,
	Jakub Kicinski <kuba@kernel.org>,
	Marek Majkowski <marek@cloudflare.com>,
	Lorenz Bauer <lmb@cloudflare.com>
Subject: [PATCH bpf-next 10/17] udp: Run SK_LOOKUP BPF program on socket lookup
Date: Wed,  6 May 2020 14:55:06 +0200	[thread overview]
Message-ID: <20200506125514.1020829-11-jakub@cloudflare.com> (raw)
In-Reply-To: <20200506125514.1020829-1-jakub@cloudflare.com>

Following INET/TCP socket lookup changes, modify UDP socket lookup to let
BPF program select a receiving socket before searching for a socket by
destination address and port as usual.

Lookup of connected sockets that match packet 4-tuple is unaffected by this
change. BPF program runs, and potentially overrides the lookup result, only
if a 4-tuple match was not found.

Suggested-by: Marek Majkowski <marek@cloudflare.com>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
---
 net/ipv4/udp.c | 36 ++++++++++++++++++++++++++++--------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index d4842f29294a..18d8432f6551 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -460,7 +460,7 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 		__be16 sport, __be32 daddr, __be16 dport, int dif,
 		int sdif, struct udp_table *udptable, struct sk_buff *skb)
 {
-	struct sock *result;
+	struct sock *result, *sk, *reuse_sk;
 	unsigned short hnum = ntohs(dport);
 	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
@@ -469,18 +469,38 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 	slot2 = hash2 & udptable->mask;
 	hslot2 = &udptable->hash2[slot2];
 
+	/* Lookup connected or non-wildcard socket */
 	result = udp4_lib_lookup2(net, saddr, sport,
 				  daddr, hnum, dif, sdif,
 				  hslot2, skb);
-	if (!result) {
-		hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
-		slot2 = hash2 & udptable->mask;
-		hslot2 = &udptable->hash2[slot2];
+	if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
+		goto done;
 
-		result = udp4_lib_lookup2(net, saddr, sport,
-					  htonl(INADDR_ANY), hnum, dif, sdif,
-					  hslot2, skb);
+	/* Lookup redirect from BPF */
+	sk = inet_lookup_run_bpf(net, udptable->protocol,
+				 saddr, sport, daddr, hnum);
+	if (IS_ERR(sk))
+		return NULL;
+	if (sk) {
+		reuse_sk = lookup_reuseport(net, sk, skb,
+					    saddr, sport, daddr, hnum);
+		result = reuse_sk ? : sk;
+		goto done;
 	}
+
+	/* Got non-wildcard socket or error on first lookup */
+	if (result)
+		goto done;
+
+	/* Lookup wildcard sockets */
+	hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
+	slot2 = hash2 & udptable->mask;
+	hslot2 = &udptable->hash2[slot2];
+
+	result = udp4_lib_lookup2(net, saddr, sport,
+				  htonl(INADDR_ANY), hnum, dif, sdif,
+				  hslot2, skb);
+done:
 	if (IS_ERR(result))
 		return NULL;
 	return result;
-- 
2.25.3


  parent reply	other threads:[~2020-05-06 12:56 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-06 12:54 [PATCH bpf-next 00/17] Run a BPF program on socket lookup Jakub Sitnicki
2020-05-06 12:54 ` [PATCH bpf-next 01/17] flow_dissector: Extract attach/detach/query helpers Jakub Sitnicki
2020-05-06 12:54 ` [PATCH bpf-next 02/17] bpf: Introduce SK_LOOKUP program type with a dedicated attach point Jakub Sitnicki
2020-05-06 13:16   ` Lorenz Bauer
2020-05-06 13:53     ` Jakub Sitnicki
2020-05-07 20:55       ` Martin KaFai Lau
2020-05-08  8:54         ` Jakub Sitnicki
2020-05-08  7:06   ` Martin KaFai Lau
2020-05-08 10:45     ` Jakub Sitnicki
2020-05-08 18:39       ` Martin KaFai Lau
2020-05-11  9:08         ` Jakub Sitnicki
2020-05-11 18:59           ` Martin KaFai Lau
2020-05-11 19:26             ` Jakub Sitnicki
2020-05-11 20:54               ` Martin KaFai Lau
2020-05-12 14:16                 ` Jakub Sitnicki
2020-05-06 12:54 ` [PATCH bpf-next 03/17] inet: Store layer 4 protocol in inet_hashinfo Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 04/17] inet: Extract helper for selecting socket from reuseport group Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 05/17] inet: Run SK_LOOKUP BPF program on socket lookup Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 06/17] inet6: Extract helper for selecting socket from reuseport group Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 07/17] inet6: Run SK_LOOKUP BPF program on socket lookup Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 08/17] udp: Store layer 4 protocol in udp_table Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 09/17] udp: Extract helper for selecting socket from reuseport group Jakub Sitnicki
2020-05-06 12:55 ` Jakub Sitnicki [this message]
2020-05-06 12:55 ` [PATCH bpf-next 11/17] udp6: " Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 12/17] udp6: Run SK_LOOKUP BPF program on socket lookup Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 13/17] bpf: Sync linux/bpf.h to tools/ Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 14/17] libbpf: Add support for SK_LOOKUP program type Jakub Sitnicki
2020-05-08 17:41   ` Andrii Nakryiko
2020-05-08 17:52     ` Yonghong Song
2020-05-08 17:59       ` Andrii Nakryiko
2020-05-11  8:12     ` Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 15/17] selftests/bpf: Add verifier tests for bpf_sk_lookup context access Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 16/17] selftests/bpf: Rename test_sk_lookup_kern.c to test_ref_track_kern.c Jakub Sitnicki
2020-05-06 12:55 ` [PATCH bpf-next 17/17] selftests/bpf: Tests for BPF_SK_LOOKUP attach point Jakub Sitnicki

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200506125514.1020829-11-jakub@cloudflare.com \
    --to=jakub@cloudflare.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=dccp@vger.kernel.org \
    --cc=edumazet@google.com \
    --cc=gerrit@erg.abdn.ac.uk \
    --cc=kernel-team@cloudflare.com \
    --cc=kuba@kernel.org \
    --cc=lmb@cloudflare.com \
    --cc=marek@cloudflare.com \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).