From 0dd061a6a115f25132989cbd591a25afb2dee086 Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Wed, 16 Aug 2023 09:11:56 +0800 Subject: bpf: Add update_socket_protocol hook Add a hook named update_socket_protocol in __sys_socket(), for bpf progs to attach to and update socket protocol. One user case is to force legacy TCP apps to create and use MPTCP sockets instead of TCP ones. Define a fmod_ret set named bpf_mptcp_fmodret_ids, add the hook update_socket_protocol into this set, and register it in bpf_mptcp_kfunc_init(). Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/79 Acked-by: Matthieu Baerts Acked-by: Yonghong Song Signed-off-by: Geliang Tang Link: https://lore.kernel.org/r/ac84be00f97072a46f8a72b4e2be46cbb7fa5053.1692147782.git.geliang.tang@suse.com Signed-off-by: Martin KaFai Lau --- net/mptcp/bpf.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'net/mptcp') diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c index 5a0a84ad94af..8a16672b94e2 100644 --- a/net/mptcp/bpf.c +++ b/net/mptcp/bpf.c @@ -19,3 +19,18 @@ struct mptcp_sock *bpf_mptcp_sock_from_subflow(struct sock *sk) return NULL; } + +BTF_SET8_START(bpf_mptcp_fmodret_ids) +BTF_ID_FLAGS(func, update_socket_protocol) +BTF_SET8_END(bpf_mptcp_fmodret_ids) + +static const struct btf_kfunc_id_set bpf_mptcp_fmodret_set = { + .owner = THIS_MODULE, + .set = &bpf_mptcp_fmodret_ids, +}; + +static int __init bpf_mptcp_kfunc_init(void) +{ + return register_btf_fmodret_id_set(&bpf_mptcp_fmodret_set); +} +late_initcall(bpf_mptcp_kfunc_init); -- cgit v1.2.3