[PATCH bpf-next v3 0/7] Add SO_REUSEPORT support for TC bpf_sk_assign

From: Lorenz Bauer <lmb@isovalent.com>
To: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	David Ahern <dsahern@kernel.org>,
	Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	Martin KaFai Lau <martin.lau@linux.dev>,
	Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
	John Fastabend <john.fastabend@gmail.com>,
	KP Singh <kpsingh@kernel.org>,
	Stanislav Fomichev <sdf@google.com>, Hao Luo <haoluo@google.com>,
	Jiri Olsa <jolsa@kernel.org>, Joe Stringer <joe@wand.net.nz>,
	Mykola Lysenko <mykolal@fb.com>, Shuah Khan <shuah@kernel.org>,
	Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Hemanth Malla <hemanthmalla@gmail.com>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
	Lorenz Bauer <lmb@isovalent.com>, Joe Stringer <joe@cilium.io>
Subject: [PATCH bpf-next v3 0/7] Add SO_REUSEPORT support for TC bpf_sk_assign
Date: Mon, 26 Jun 2023 16:08:57 +0100	[thread overview]
Message-ID: <20230613-so-reuseport-v3-0-907b4cbb7b99@isovalent.com> (raw)

We want to replace iptables TPROXY with a BPF program at TC ingress.
To make this work in all cases we need to assign a SO_REUSEPORT socket
to an skb, which is currently prohibited. This series adds support for
such sockets to bpf_sk_assing.

I did some refactoring to cut down on the amount of duplicate code. The
key to this is to use INDIRECT_CALL in the reuseport helpers. To show
that this approach is not just beneficial to TC sk_assign I removed
duplicate code for bpf_sk_lookup as well.

Changes from v1:
- Correct commit abbrev length (Kuniyuki)
- Reduce duplication (Kuniyuki)
- Add checks on sk_state (Martin)
- Split exporting inet[6]_lookup_reuseport into separate patch (Eric)

Joint work with Daniel Borkmann.

Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
---
Changes in v3:
- Fix warning re udp_ehashfn and udp6_ehashfn (Simon)
- Return higher scoring connected UDP reuseport sockets (Kuniyuki)
- Fix ipv6 module builds
- Link to v2: https://lore.kernel.org/r/20230613-so-reuseport-v2-0-b7c69a342613@isovalent.com

---
Daniel Borkmann (1):
      selftests/bpf: Test that SO_REUSEPORT can be used with sk_assign helper

Lorenz Bauer (6):
      udp: re-score reuseport groups when connected sockets are present
      net: export inet_lookup_reuseport and inet6_lookup_reuseport
      net: document inet[6]_lookup_reuseport sk_state requirements
      net: remove duplicate reuseport_lookup functions
      net: remove duplicate sk_lookup helpers
      bpf, net: Support SO_REUSEPORT sockets with bpf_sk_assign

 include/net/inet6_hashtables.h                     |  84 ++++++++-
 include/net/inet_hashtables.h                      |  77 +++++++-
 include/net/sock.h                                 |   7 +-
 include/net/udp.h                                  |   8 +
 include/uapi/linux/bpf.h                           |   3 -
 net/core/filter.c                                  |   2 -
 net/ipv4/inet_hashtables.c                         |  70 +++++---
 net/ipv4/udp.c                                     |  88 ++++-----
 net/ipv6/inet6_hashtables.c                        |  73 +++++---
 net/ipv6/udp.c                                     |  98 ++++------
 tools/include/uapi/linux/bpf.h                     |   3 -
 tools/testing/selftests/bpf/network_helpers.c      |   3 +
 .../selftests/bpf/prog_tests/assign_reuse.c        | 197 +++++++++++++++++++++
 .../selftests/bpf/progs/test_assign_reuse.c        | 142 +++++++++++++++
 14 files changed, 676 insertions(+), 179 deletions(-)
---
base-commit: 970308a7b544fa1c7ee98a2721faba3765be8dd8
change-id: 20230613-so-reuseport-e92c526173ee

Best regards,
-- 
Lorenz Bauer <lmb@isovalent.com>