From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yx1-f44.google.com (mail-yx1-f44.google.com [74.125.224.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8DCB419CCF7 for ; Sun, 29 Mar 2026 04:19:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.224.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774757980; cv=none; b=mEdavvzCGFcbPfwBUqNGPETCgveTulUW2StHPLKuOjiHAjzqW7LYv0jZ+DtoE2BbTVUigxfOz5UkXFQrTWmiaG/BKpNWv+VgGIqWZrNMaCcxcJYcxHs3KsGG92aTNVT6m++W+mPUtO26pyFN5y1Zi0XC2DCqjIMe/fVyZB63uW8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774757980; c=relaxed/simple; bh=zT2RqGd3nP3UCMWCKPndkuHNOyLMnz4Yhzwh6iq/cJM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oVsW9M1qI5KTq3Bx7qa1gZr/iyZjdD0PFO3LtqY7hdoqDKfpTb0a9oWAD5RVt2ljn0HilgOZPZ5fYucHWyD79H+jcs2TdPI5hOb5EbZtW+juiUDt62T8jjglUn0LJ5uAEY9haUneZ8FfXmpcam3emy7f2FjQ4wHP7rdT+cev5kU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=jNHcCNxq; arc=none smtp.client-ip=74.125.224.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jNHcCNxq" Received: by mail-yx1-f44.google.com with SMTP id 956f58d0204a3-64ee072d105so479550d50.3 for ; Sat, 28 Mar 2026 21:19:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1774757978; x=1775362778; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=LYF9EK7KgmEP8ho0Nd5jF1xsN/C9b5ZrS1epvozHDgQ=; b=jNHcCNxqoowC8wdD9CiD852e75RHmUvCDEAw3UeKgdHdi9npmSu0uqCkp0aqgbySGu Fhgf0jG5yk8Kyzh6s11hVk/zGWm85WzzrftNhr0qfvIhes3ryVB0ICbPZ1NyZU9dPvlN PArdGxY2sS3p8X9Ss0sr/jwPMJyi0NhpLG4E7BKfiavw+KhYytiy/KNs/d90OX2JKyga sAjd2QQF4mIiCYOfwUmM3mHxmyQAad2rfuLQvWXxz0n+ptlW86ftMuQhjkns99tiTvfg tGo40zrsGFKpuS4FNReG/Jff0LCvbRNbWX/Qe+AjLk1L6WtTJtQlTgBhT8OL3qsSNAm/ vZNQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774757978; x=1775362778; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=LYF9EK7KgmEP8ho0Nd5jF1xsN/C9b5ZrS1epvozHDgQ=; b=YJhiOojoyktYc2xJDJW81jYl2jU424KlGp6/Iq+Wuwhel91H3hLRWPUUoarArHB1Gj KJt9k+P4aqdD1jwaU2uhJPG0fQEmlBKNTb3WWiLs44xPltXra7YT2r9iwGJ6YOdV60OY txzxoa2gvmPHHGuGJgWOKz7p13qFsii0tiPQbkWQljzmw3EgoMizy8IgIZfhZ5mJnJQu Y/vKeuiMUgPg7KkxL4WNEpbCm0Qdl1MAj6m5WgwUVgbSa666xX075Te1bR1Fyc7cxnw4 wgltXBl32C3EDmf6AETXfL/bQF90okgsMDzUpjfvh7xnb0bIf3Qim34xFBKcXTeEuJ7m QObg== X-Gm-Message-State: AOJu0YyaJ4lHIQzyxVHaqg3jHurHAQkCYD7Y+AGa4HUrsyTOIQIQ15LW bdQxC5E3Kkzl0t6Ax6qbaADsZqurqpYje7+nrc3UnI+CEWxX4HNuYGixInYtVjxC X-Gm-Gg: ATEYQzzNsJD3i/qkZmiatI000Wo3tnFbq8TXDHjWdnP7ldl3d51CgL09Tvg9rainCLE Qf3nSvy3XqoS6Wnt6EaSNWvJeAtTHsLGmYrTkdplvtBX4VT7dr87BqvMpxnshdwOTwiptbdVLOm 2f7SsGHhtiVAGj/o210JM/0+2BzT4Y8lawE6RDnqn4OQCiOGuXvhVGPTEtOQ6q1umqNPKLoPh3E 9gvWyxVY0NX9y471AfYqwLTK/e6408DToTdrOyuBuZ1ahYU0eZZAvSO9j6VvI8ypVTMNnhUehU/ M2MTnnmZaxEhE5yH5GhPaKPLesa47rhFwp4Z2m5sR8ZVeZACoqQHOZsXZjOlZCj7gFdGTbGSUI4 HxGeB9THrJFkvv+BGzpCNcEnNz3dvP2hikUNNZcwd2wi0ni19OTg6NB4YEbZwGg8dxewWjwnXQ0 kKo1YgP1/YOSVtn33kozCsMSmR X-Received: by 2002:a05:690e:1918:b0:64e:dc58:1ad4 with SMTP id 956f58d0204a3-64ff7195e07mr5805687d50.2.1774757978454; Sat, 28 Mar 2026 21:19:38 -0700 (PDT) Received: from localhost ([2a03:2880:21ff:72::]) by smtp.gmail.com with ESMTPSA id 956f58d0204a3-65008fe9c3asm2026084d50.0.2026.03.28.21.19.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 28 Mar 2026 21:19:38 -0700 (PDT) From: Wei Wang To: netdev@vger.kernel.org, Jakub Kicinski , Daniel Zahka , Willem de Bruijn , David Wei , Andrew Lunn , "David S . Miller" , Eric Dumazet , Simon Horman Cc: Wei Wang , Bobby Eshleman Subject: [PATCH v8 net-next 4/5] selftests/net: Add bpf skb forwarding program Date: Sat, 28 Mar 2026 21:19:20 -0700 Message-ID: <20260329041922.3850747-5-weibunny.kernel@gmail.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260329041922.3850747-1-weibunny.kernel@gmail.com> References: <20260329041922.3850747-1-weibunny.kernel@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Wei Wang Add nk_redirect.bpf.c, a BPF program that forwards skbs matching some IPv6 prefix received on eth0 ifindex to a specified dev ifindex. bpf_redirect_neigh() is used to make sure neighbor lookup is performed and proper MAC addr is being used. Signed-off-by: Wei Wang Reviewed-by: Bobby Eshleman Tested-by: Bobby Eshleman --- .../drivers/net/hw/nk_redirect.bpf.c | 60 +++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 tools/testing/selftests/drivers/net/hw/nk_redirect.bpf.c diff --git a/tools/testing/selftests/drivers/net/hw/nk_redirect.bpf.c b/tools/testing/selftests/drivers/net/hw/nk_redirect.bpf.c new file mode 100644 index 000000000000..7ac9ffd50f15 --- /dev/null +++ b/tools/testing/selftests/drivers/net/hw/nk_redirect.bpf.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * BPF program for redirecting traffic using bpf_redirect_neigh(). + * Unlike bpf_redirect() which preserves L2 headers, bpf_redirect_neigh() + * performs neighbor lookup and fills in the correct L2 addresses for the + * target interface. This is necessary when redirecting across different + * device types (e.g., from netdevsim to netkit). + */ +#include +#include +#include +#include +#include +#include +#include + +#define TC_ACT_OK 0 +#define ETH_P_IPV6 0x86DD + +#define ctx_ptr(field) ((void *)(long)(field)) + +#define v6_p64_equal(a, b) (a.s6_addr32[0] == b.s6_addr32[0] && \ + a.s6_addr32[1] == b.s6_addr32[1]) + +volatile __u32 redirect_ifindex; +volatile __u8 ipv6_prefix[16]; + +SEC("tc/ingress") +int tc_redirect(struct __sk_buff *skb) +{ + void *data_end = ctx_ptr(skb->data_end); + void *data = ctx_ptr(skb->data); + struct in6_addr *match_prefix; + struct ipv6hdr *ip6h; + struct ethhdr *eth; + + match_prefix = (struct in6_addr *)ipv6_prefix; + + if (skb->protocol != bpf_htons(ETH_P_IPV6)) + return TC_ACT_OK; + + eth = data; + if ((void *)(eth + 1) > data_end) + return TC_ACT_OK; + + ip6h = data + sizeof(struct ethhdr); + if ((void *)(ip6h + 1) > data_end) + return TC_ACT_OK; + + if (!v6_p64_equal(ip6h->daddr, (*match_prefix))) + return TC_ACT_OK; + + /* + * Use bpf_redirect_neigh() to perform neighbor lookup and fill in + * correct L2 addresses for the target interface. + */ + return bpf_redirect_neigh(redirect_ifindex, NULL, 0, 0); +} + +char __license[] SEC("license") = "GPL"; -- 2.52.0