From nobody Fri Nov 22 12:50:45 2024 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 BDCAD205E1F for ; Tue, 3 Sep 2024 08:05:11 +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=1725350711; cv=none; b=BmGWmIdKWO8HbcqgAwWcGjmsDI+q/uV3ICe/mus6bDBcpiIHRrovD1RCphbKHd6TrssRznau2ZL+DtUZOkCM6SkFoTDcrYoNmbHOs1ZsfXFinIOFp6MyQNTRadux6V7tokQzQhUY0htrlUE/oZ3oeQV5U6q14BhSxg4PM/zNfd4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725350711; c=relaxed/simple; bh=2zoj9L0O/GSybtYkl/vHnS8JQ1/n2Tg3DY2FQ0e64yg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YxZVoJ8MY8bTHrT/oVvERThpgL4CcgnEO7MWby4OcBCpe/XbXDj+3wgE8u58EVsvcHyasNkUVazHod7ITupcuvLgbP9/KML97omwuIO1YmNwVKxLlRYv2WCrkp7eWm4f1OMduONtYNiVF0JeZzb6W0LP4JjXVdtfqgdfYyMnldM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SWshAXyK; 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="SWshAXyK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DEFF5C4CEC8; Tue, 3 Sep 2024 08:05:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725350711; bh=2zoj9L0O/GSybtYkl/vHnS8JQ1/n2Tg3DY2FQ0e64yg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SWshAXyKNaDWhK268r+s7iWPrwb9D6u7iqnQFOOfwHB/En3MVEsUrs1VyPO4yp3mz /5/rqkDPIZV+JrXPkA+qNz/rQF0Bw9QTPcut2lBGdrfveRoWzl4Rr6VpVIE+zVcvGN juNacpRoq7kG19x+PCxeNQHcAssGqndJNDyMry+eHtei01kNl1e4aneEfPGy0Wx1kn t49aP9Lycd2d5UN5QQFs/81ieiKS/zbfymDyWraTrYvzXlPSlQIFBa9gOvzFhUWzsv HSyBgqMoQ3yAuyEQA45TYNyPA/OV1mvrEXaN0VIVTXU+LVOIp5IxJ29DX62+z8KG6Y xhQdRuMRfJpMw== From: Geliang Tang To: mptcp@lists.linux.dev Cc: Geliang Tang , Martin KaFai Lau Subject: [PATCH mptcp-next v7 2/4] selftests/bpf: Add getsockopt to inspect mptcp subflow Date: Tue, 3 Sep 2024 16:04:58 +0800 Message-ID: <2cd5946354c8cf839684274e9ccc52016fbcf717.1725350462.git.tanggeliang@kylinos.cn> X-Mailer: git-send-email 2.43.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Geliang Tang This patch adds a "cgroup/getsockopt" way to inspect the subflows of a mptcp socket. mptcp_for_each_stubflow() and other helpers related to list_dentry are added into progs/mptcp_bpf.h. Add an extra "cgroup/getsockopt" prog to walk the msk->conn_list and use bpf_core_cast to cast a pointer to tcp_sock for readonly. It will allow to inspect all the fields in a tcp_sock. Suggested-by: Martin KaFai Lau Signed-off-by: Geliang Tang --- tools/testing/selftests/bpf/progs/mptcp_bpf.h | 27 ++++++ .../selftests/bpf/progs/mptcp_subflow.c | 90 +++++++++++++++++++ 2 files changed, 117 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf.h b/tools/testing/= selftests/bpf/progs/mptcp_bpf.h index 782f36ed027e..92d5deed0214 100644 --- a/tools/testing/selftests/bpf/progs/mptcp_bpf.h +++ b/tools/testing/selftests/bpf/progs/mptcp_bpf.h @@ -4,9 +4,36 @@ =20 #include #include +#include "bpf_experimental.h" =20 #define MPTCP_SUBFLOWS_MAX 8 =20 +static inline int list_is_head(const struct list_head *list, + const struct list_head *head) +{ + return list =3D=3D head; +} + +#define list_entry(ptr, type, member) \ + container_of(ptr, type, member) + +#define list_first_entry(ptr, type, member) \ + list_entry((ptr)->next, type, member) + +#define list_next_entry(pos, member) \ + list_entry((pos)->member.next, typeof(*(pos)), member) + +#define list_entry_is_head(pos, head, member) \ + list_is_head(&pos->member, (head)) + +#define list_for_each_entry(pos, head, member) \ + for (pos =3D list_first_entry(head, typeof(*pos), member); \ + cond_break, !list_entry_is_head(pos, head, member); \ + pos =3D list_next_entry(pos, member)) + +#define mptcp_for_each_subflow(__msk, __subflow) \ + list_for_each_entry(__subflow, &((__msk)->conn_list), node) + extern void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subf= low, bool scheduled) __ksym; =20 diff --git a/tools/testing/selftests/bpf/progs/mptcp_subflow.c b/tools/test= ing/selftests/bpf/progs/mptcp_subflow.c index 2e28f4a215b5..1053a795eb43 100644 --- a/tools/testing/selftests/bpf/progs/mptcp_subflow.c +++ b/tools/testing/selftests/bpf/progs/mptcp_subflow.c @@ -4,6 +4,7 @@ =20 /* vmlinux.h, bpf_helpers.h and other 'define' */ #include "bpf_tracing_net.h" +#include "mptcp_bpf.h" =20 char _license[] SEC("license") =3D "GPL"; =20 @@ -57,3 +58,92 @@ int mptcp_subflow(struct bpf_sock_ops *skops) =20 return 1; } + +static int _check_getsockopt_subflow_mark(struct bpf_sock *sk) +{ + struct mptcp_subflow_context *subflow; + struct mptcp_sock *msk; + int i =3D 0; + + if (sk->protocol !=3D IPPROTO_MPTCP) { + bpf_printk("MPTCP Subflow: unexpected protocol %u", sk->protocol); + return -1; + } + + msk =3D bpf_core_cast(sk, struct mptcp_sock); + if (msk->pm.subflows !=3D 1) { + bpf_printk("MPTCP Subflow: expected 1 extra subflows, got %u", + msk->pm.subflows); + return -1; + } + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk; + + ssk =3D mptcp_subflow_tcp_sock(bpf_core_cast(subflow, + struct mptcp_subflow_context)); + + if (ssk->sk_mark !=3D ++i) { + bpf_printk("MPTCP Subflow: expected %d mark, got %d", + i, ssk->sk_mark); + return -1; + } + } + + return 0; +} + +static int _check_getsockopt_subflow_cc(struct bpf_sock *sk) +{ + struct mptcp_subflow_context *subflow; + struct mptcp_sock *msk; + + if (sk->protocol !=3D IPPROTO_MPTCP) { + bpf_printk("MPTCP Subflow: unexpected protocol %u", sk->protocol); + return -1; + } + + msk =3D bpf_core_cast(sk, struct mptcp_sock); + if (msk->pm.subflows !=3D 1) { + bpf_printk("MPTCP Subflow: expected 1 extra subflows, got %u", + msk->pm.subflows); + return -1; + } + + mptcp_for_each_subflow(msk, subflow) { + struct inet_connection_sock *icsk; + struct sock *ssk; + + ssk =3D mptcp_subflow_tcp_sock(bpf_core_cast(subflow, + struct mptcp_subflow_context)); + icsk =3D bpf_core_cast(ssk, struct inet_connection_sock); + + if (ssk->sk_mark =3D=3D 2 && + __builtin_memcmp(icsk->icsk_ca_ops->name, cc, TCP_CA_NAME_MAX)) { + bpf_printk("MPTCP Subflow: expected %s cc, got %s", + cc, icsk->icsk_ca_ops->name); + return -1; + } + } + + return 0; +} + +SEC("cgroup/getsockopt") +int _getsockopt_subflow(struct bpf_sockopt *ctx) +{ + struct bpf_sock *sk =3D ctx->sk; + + if (!sk) { + bpf_printk("MPTCP Subflow: unexpected socket, sk is NULL"); + ctx->retval =3D -1; + return 1; + } + + if (ctx->level =3D=3D SOL_SOCKET && ctx->optname =3D=3D SO_MARK) + ctx->retval =3D _check_getsockopt_subflow_mark(sk); + else if (ctx->level =3D=3D SOL_TCP && ctx->optname =3D=3D TCP_CONGESTION) + ctx->retval =3D _check_getsockopt_subflow_cc(sk); + + return 1; +} --=20 2.43.0