From nobody Tue May 13 21:07:08 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 574C31C84BF for <mptcp@lists.linux.dev>; Fri, 21 Mar 2025 01:49:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742521767; cv=none; b=DRtB7Ij+iVfYM1x39Uz37g10aczJAadsJ3exjKNQ9thTrEbNkJgYltlkmoflcSNRPhuDRydQxayB60w50MOC/eMPGBe+YfH3GUTk+60KSp5ZBdjjxhs8rWDVTZBnKcuaNnW6jIdzkhyy2btQ1GHbPg1IqfZYGhPbpdL+UEXnbcA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742521767; c=relaxed/simple; bh=NwQ2ZrePdycqSz9krQSAuwnz1skNScibMGwVHXBjl/g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=l5xOxg1BUcggzYRUmMCOwFH13sogAugjJTNe1AVCwGz/Nr0KFfwFtIO8NVLhDodx3syeuERoZXNy4YtJ2Y04O3rKahCBRVQzCgph7oL4As60fbPEmpDpPgh2r5wkqJJ5ciWm9R/6rJ1OvRvMOtrwfg2RG2nar5+z3deE50QdZd0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lN2je9wa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lN2je9wa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39585C4CEE7; Fri, 21 Mar 2025 01:49:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1742521767; bh=NwQ2ZrePdycqSz9krQSAuwnz1skNScibMGwVHXBjl/g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lN2je9waULQIfZYFjAMWrxBqHWPzylYH+nq/H+YGHc+LHhyzMYWDot82y6PKrcAHX FteJz9AcudaF5SyXEzDKK5Af6zsn0yYfy13luvYEZDuMsSFRyp06/09fsT7rMATbYp 5Ssw6Hxm/9FsqoPrd1kdKFPcC1RpWPC2USpuFRW1iS+87QqwPjsiYh/Ukywxo32nM2 NlNbAM33/7DPkqvmzw9hqKFr4xHRj0AIlLdCdhKt+ayiF0UstGRE6cBVzMi70RFjz3 5PoZWQXhopjcZpQ4lkPRRSU0imkH0JcAVT/MROTXOb8mTknkgGrXrv3Vuw/Wu6wkVB JGLmyL0jb4bqg== From: Geliang Tang <geliang@kernel.org> To: mptcp@lists.linux.dev Cc: Geliang Tang <tanggeliang@kylinos.cn> Subject: [PATCH mptcp-next v1 1/4] bpf: Add mptcp path manager struct_ops Date: Fri, 21 Mar 2025 09:49:15 +0800 Message-ID: <aa77f73b6b6227cf88fd4aae77c5604593bf79d8.1742521587.git.tanggeliang@kylinos.cn> X-Mailer: git-send-email 2.43.0 In-Reply-To: <cover.1742521587.git.tanggeliang@kylinos.cn> References: <cover.1742521587.git.tanggeliang@kylinos.cn> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: <mptcp.lists.linux.dev> List-Subscribe: <mailto:mptcp+subscribe@lists.linux.dev> List-Unsubscribe: <mailto:mptcp+unsubscribe@lists.linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Geliang Tang <tanggeliang@kylinos.cn> This patch implements a new struct bpf_struct_ops for MPTCP BPF path manager: bpf_mptcp_pm_ops. Register and unregister the bpf path manager in .reg and .unreg. Add write access for some fields of struct mptcp_sock and struct mptcp_pm_addr_entry in .btf_struct_access. This MPTCP BPF path manager implementation is similar to BPF TCP CC. And net/ipv4/bpf_tcp_ca.c is a frame of reference for this patch. Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn> --- net/mptcp/bpf.c | 259 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 258 insertions(+), 1 deletion(-) diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c index 2b0cfb57df8c..596574102b89 100644 --- a/net/mptcp/bpf.c +++ b/net/mptcp/bpf.c @@ -17,10 +17,266 @@ #include "protocol.h" =20 #ifdef CONFIG_BPF_JIT -static struct bpf_struct_ops bpf_mptcp_sched_ops; +static struct bpf_struct_ops bpf_mptcp_pm_ops, + bpf_mptcp_sched_ops; static u32 mptcp_sock_id, + mptcp_entry_id, mptcp_subflow_id; =20 +/* MPTCP BPF path manager */ + +static const struct bpf_func_proto * +bpf_mptcp_pm_get_func_proto(enum bpf_func_id func_id, + const struct bpf_prog *prog) +{ + switch (func_id) { + case BPF_FUNC_sk_storage_get: + return &bpf_sk_storage_get_proto; + case BPF_FUNC_sk_storage_delete: + return &bpf_sk_storage_delete_proto; + default: + return bpf_base_func_proto(func_id, prog); + } +} + +static int bpf_mptcp_pm_btf_struct_access(struct bpf_verifier_log *log, + const struct bpf_reg_state *reg, + int off, int size) +{ + u32 id =3D reg->btf_id; + size_t end; + + if (id =3D=3D mptcp_sock_id) { + switch (off) { + case offsetof(struct mptcp_sock, pm.remote.id): + end =3D offsetofend(struct mptcp_sock, pm.remote.id); + break; + case offsetof(struct mptcp_sock, pm.remote.family): + end =3D offsetofend(struct mptcp_sock, pm.remote.family); + break; + case offsetof(struct mptcp_sock, pm.remote.port): + end =3D offsetofend(struct mptcp_sock, pm.remote.port); + break; +#if IS_ENABLED(CONFIG_MPTCP_IPV6) + case offsetof(struct mptcp_sock, pm.remote.addr6.s6_addr32[0]): + end =3D offsetofend(struct mptcp_sock, pm.remote.addr6.s6_addr32[0]); + break; + case offsetof(struct mptcp_sock, pm.remote.addr6.s6_addr32[1]): + end =3D offsetofend(struct mptcp_sock, pm.remote.addr6.s6_addr32[1]); + break; + case offsetof(struct mptcp_sock, pm.remote.addr6.s6_addr32[2]): + end =3D offsetofend(struct mptcp_sock, pm.remote.addr6.s6_addr32[2]); + break; + case offsetof(struct mptcp_sock, pm.remote.addr6.s6_addr32[3]): + end =3D offsetofend(struct mptcp_sock, pm.remote.addr6.s6_addr32[3]); + break; +#else + case offsetof(struct mptcp_sock, pm.remote.addr.s_addr): + end =3D offsetofend(struct mptcp_sock, pm.remote.addr.s_addr); + break; +#endif + case offsetof(struct mptcp_sock, pm.work_pending): + end =3D offsetofend(struct mptcp_sock, pm.work_pending); + break; + case offsetof(struct mptcp_sock, pm.accept_addr): + end =3D offsetofend(struct mptcp_sock, pm.accept_addr); + break; + case offsetof(struct mptcp_sock, pm.accept_subflow): + end =3D offsetofend(struct mptcp_sock, pm.accept_subflow); + break; + case offsetof(struct mptcp_sock, pm.add_addr_signaled): + end =3D offsetofend(struct mptcp_sock, pm.add_addr_signaled); + break; + case offsetof(struct mptcp_sock, pm.local_addr_used): + end =3D offsetofend(struct mptcp_sock, pm.local_addr_used); + break; + case offsetof(struct mptcp_sock, pm.subflows): + end =3D offsetofend(struct mptcp_sock, pm.subflows); + break; + default: + bpf_log(log, "no write support to mptcp_sock at off %d\n", + off); + return -EACCES; + } + } else if (id =3D=3D mptcp_entry_id) { + switch (off) { + case offsetof(struct mptcp_pm_addr_entry, addr.id): + end =3D offsetofend(struct mptcp_pm_addr_entry, addr.id); + break; + case offsetof(struct mptcp_pm_addr_entry, addr.port): + end =3D offsetofend(struct mptcp_pm_addr_entry, addr.port); + break; + default: + bpf_log(log, "no write support to mptcp_pm_addr_entry at off %d\n", + off); + return -EACCES; + } + } else { + bpf_log(log, "only access to mptcp sock or addr or entry is supported\n"= ); + return -EACCES; + } + + if (off + size > end) { + bpf_log(log, "access beyond %s at off %u size %u ended at %zu", + id =3D=3D mptcp_sock_id ? "mptcp_sock" : + (id =3D=3D mptcp_entry_id ? "mptcp_pm_addr_entry" : "mptcp_addr_info"), + off, size, end); + return -EACCES; + } + + return NOT_INIT; +} + +static const struct bpf_verifier_ops bpf_mptcp_pm_verifier_ops =3D { + .get_func_proto =3D bpf_mptcp_pm_get_func_proto, + .is_valid_access =3D bpf_tracing_btf_ctx_access, + .btf_struct_access =3D bpf_mptcp_pm_btf_struct_access, +}; + +static int bpf_mptcp_pm_reg(void *kdata, struct bpf_link *link) +{ + return mptcp_pm_register(kdata); +} + +static void bpf_mptcp_pm_unreg(void *kdata, struct bpf_link *link) +{ + mptcp_pm_unregister(kdata); +} + +static int bpf_mptcp_pm_check_member(const struct btf_type *t, + const struct btf_member *member, + const struct bpf_prog *prog) +{ + return 0; +} + +static int bpf_mptcp_pm_init_member(const struct btf_type *t, + const struct btf_member *member, + void *kdata, const void *udata) +{ + const struct mptcp_pm_ops *upm; + struct mptcp_pm_ops *pm; + u32 moff; + + upm =3D (const struct mptcp_pm_ops *)udata; + pm =3D (struct mptcp_pm_ops *)kdata; + + moff =3D __btf_member_bit_offset(t, member) / 8; + switch (moff) { + case offsetof(struct mptcp_pm_ops, name): + if (bpf_obj_name_cpy(pm->name, upm->name, + sizeof(pm->name)) <=3D 0) + return -EINVAL; + return 1; + } + + return 0; +} + +static int bpf_mptcp_pm_init(struct btf *btf) +{ + s32 type_id; + + type_id =3D btf_find_by_name_kind(btf, "mptcp_sock", + BTF_KIND_STRUCT); + if (type_id < 0) + return -EINVAL; + mptcp_sock_id =3D type_id; + + type_id =3D btf_find_by_name_kind(btf, "mptcp_pm_addr_entry", + BTF_KIND_STRUCT); + if (type_id < 0) + return -EINVAL; + mptcp_entry_id =3D type_id; + + return 0; +} + +static int bpf_mptcp_pm_validate(void *kdata) +{ + return mptcp_pm_validate(kdata); +} + +static int __bpf_mptcp_pm_get_local_id(struct mptcp_sock *msk, + struct mptcp_pm_addr_entry *skc) +{ + return 0; +} + +static bool __bpf_mptcp_pm_get_priority(struct mptcp_sock *msk, + struct mptcp_addr_info *skc) +{ + return false; +} + +static void __bpf_mptcp_pm_established(struct mptcp_sock *msk) +{ +} + +static void __bpf_mptcp_pm_subflow_established(struct mptcp_sock *msk) +{ +} + +static bool __bpf_mptcp_pm_allow_new_subflow(struct mptcp_sock *msk) +{ + return false; +} + +static bool __bpf_mptcp_pm_accept_new_subflow(const struct mptcp_sock *msk) +{ + return false; +} + +static bool __bpf_mptcp_pm_add_addr_echo(struct mptcp_sock *msk, + const struct mptcp_addr_info *addr) +{ + return false; +} + +static int __bpf_mptcp_pm_add_addr_received(struct mptcp_sock *msk, + const struct mptcp_addr_info *addr) +{ + return 0; +} + +static void __bpf_mptcp_pm_rm_addr_received(struct mptcp_sock *msk) +{ +} + +static void __bpf_mptcp_pm_init(struct mptcp_sock *msk) +{ +} + +static void __bpf_mptcp_pm_release(struct mptcp_sock *msk) +{ +} + +static struct mptcp_pm_ops __bpf_mptcp_pm_ops =3D { + .get_local_id =3D __bpf_mptcp_pm_get_local_id, + .get_priority =3D __bpf_mptcp_pm_get_priority, + .established =3D __bpf_mptcp_pm_established, + .subflow_established =3D __bpf_mptcp_pm_subflow_established, + .allow_new_subflow =3D __bpf_mptcp_pm_allow_new_subflow, + .accept_new_subflow =3D __bpf_mptcp_pm_accept_new_subflow, + .add_addr_echo =3D __bpf_mptcp_pm_add_addr_echo, + .add_addr_received =3D __bpf_mptcp_pm_add_addr_received, + .rm_addr_received =3D __bpf_mptcp_pm_rm_addr_received, + .init =3D __bpf_mptcp_pm_init, + .release =3D __bpf_mptcp_pm_release, +}; + +static struct bpf_struct_ops bpf_mptcp_pm_ops =3D { + .verifier_ops =3D &bpf_mptcp_pm_verifier_ops, + .reg =3D bpf_mptcp_pm_reg, + .unreg =3D bpf_mptcp_pm_unreg, + .check_member =3D bpf_mptcp_pm_check_member, + .init_member =3D bpf_mptcp_pm_init_member, + .init =3D bpf_mptcp_pm_init, + .validate =3D bpf_mptcp_pm_validate, + .name =3D "mptcp_pm_ops", + .cfi_stubs =3D &__bpf_mptcp_pm_ops, +}; + /* MPTCP BPF packet scheduler */ =20 static const struct bpf_func_proto * @@ -332,6 +588,7 @@ static int __init bpf_mptcp_kfunc_init(void) ret =3D ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &bpf_mptcp_common_kfunc_set); #ifdef CONFIG_BPF_JIT + ret =3D ret ?: register_bpf_struct_ops(&bpf_mptcp_pm_ops, mptcp_pm_ops); ret =3D ret ?: register_bpf_struct_ops(&bpf_mptcp_sched_ops, mptcp_sched_= ops); #endif =20 --=20 2.43.0