From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f51.google.com (mail-wm1-f51.google.com [209.85.128.51]) (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 9E02631987F; Tue, 26 Aug 2025 12:18:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.51 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756210710; cv=none; b=bPw6qt5LU7L0FAZWG1royPhelXrNxM2pHEBAf5rKybFgD2isylLETHkqk1R2B24MgFxmU3GTeLyAcT49/yb4doApPtDkafBHhWkVbRZic3l0kv/dG22ykQJLYyyw6C9jlIt9xrpq14wlTb6R1CB6TZIq6apFYWj7fU6Hu9e8ZqI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756210710; c=relaxed/simple; bh=xl7TGiKrLZLjjRkY4r2IBQ4zmCgxfGdphk5O0Hawwnk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=m4njptMu5alT+MjXxnZGmNE9kasKJLgOZ9FiSIf9OLEhKKBEOfye8XY4cNeD8GRxnJaSLsPCDf3e6qQpjOLbEEbU/j0to0Ld7MyVv2jP5Kd2NFzwW7BhncUgTtQ8hqpp0guzGIjyQwqYjDnbgQcl4OmbndR6P1KMOg95O5mbB9Y= 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=RH0ZOT/i; arc=none smtp.client-ip=209.85.128.51 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="RH0ZOT/i" Received: by mail-wm1-f51.google.com with SMTP id 5b1f17b1804b1-45b627ea685so12851055e9.1; Tue, 26 Aug 2025 05:18:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1756210707; x=1756815507; 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=uUquV0WS+fxJUivCT1xUeaF0YeOMY0unvquPcAzHaLs=; b=RH0ZOT/iBWcnwIjnL9sPGRq0kllVPxVwHR+iGnOJZ3KFES5GBQg6ye+1htZ4E5MOJ4 UPmA7RllvtrlAzLUhmNH3e4ZdosoA2/Ny0sDb2xgHFPql8KQs3Xqa1ppJmaBnEBuAEaB oG1eVx5xHBkfw2PN/zdxEseTmOuDkc32uOaHzPaqMaWRp/YNvo7BxvFTibIlPdhdjWH/ YmEyN6Ui7aDQ4KyDA9WIJKsMcndk8yMU1Hl3PZWy5ljQAnTNGWZf81hY6wj97pEQxCnz /4M9fQd5NsqygN0ua7+gZl4iqlbmrNj7hGjXYLS9aqp0EWBeFB8LSmTHhq7+1BoiL1Zp ugsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756210707; x=1756815507; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=uUquV0WS+fxJUivCT1xUeaF0YeOMY0unvquPcAzHaLs=; b=bCVYVIimYAnkU6ve1Vr0fNAzaP6fOl2CddynDnGyqfF4epMwVr9DgenMNSm4mid+uL 8l5yz1KH8TJVta2vOCNxRqY/4a7qHO3CBN1mAsTyZjCO2nD/KcqVL0njoySo/gTpAR0S sVmD/oSnzvE5uSwgHM7RfR9RuV/QHhNk+G2rJYDvu3/S97U2vVGF6H7hJ1HHj/bi2K6V 7Brxye5CB6pvZdAkf3C0kguMHKUeHl/tqYw67flDsKPmeOA2u7lVEYlsV0jM/w02NLJU HbgkboIilS81BWofQVi5vaA02UNSqhAIIOfxMzi96MVAhTQwp/KiAFx5WEOgi7w9Ub3C iRyw== X-Forwarded-Encrypted: i=1; AJvYcCV4+qyXA0vyfUSf51JeS4Ig8Bq+fWjiyYxlTW3vXa+lNShdJLAo+O51mHOqRbuKa1YP/PCRyiU=@vger.kernel.org, AJvYcCVqcohrvfXaf9XwpwC/aRY49bv5HZGkfGM31Ou36mgkIfn81z2LRSZK0jiykqAbOs8cgEibFhN8@vger.kernel.org X-Gm-Message-State: AOJu0YybvMOAzGmGFB1/56zDesrZ9IaRRXdAAAkOUqUq6A5gDxlHTKlr Mao7z1riykIliZ5wH2ZwBIeof0Ye6gZLzDI8fOdfoMPZNSRKpzZWIgA3 X-Gm-Gg: ASbGnctIpF7//I5TtCV+Ruz+toPH4sVYaUXkdZPfxNv7vmJb3kKdE6esHABsOBRn7UD 1R2gBXmz+NH/5kZudDLxAfTQMNyJR8wAXDyPeCjbVglGwLYUVkhTYT66HE9BTdSwgrmqHQ30A15 CPj8FgYUqiZ8sXlWjECLbh5tIwotINyRBJLo4Jri3hA/nEAqh+Q5WiO3Fz4EPMn0sv0J5Kq1UQs CK0yfCHhC+38Z6ueHdnkxSbqporZ6SC3S/JhbVJahtUBjNy87lNB+iJic+wSJdWCqnl/3VBy8/l 6I6QOMMaCZQtDKcZW7uWguDxPiJ3jsQUqU36JACz+XGgYX6piUAf4FNzf3NHDlc93s/uUowH3JE +rJBGeeA34miJI+R47oceKNP49UTQXyfr X-Google-Smtp-Source: AGHT+IFA+w9zyLiHWHSxzU53Rb5LUj410W6JWkcnK35EtrBXTWpbfg8retqet4NA+n39H/gbCoK57Q== X-Received: by 2002:a05:600c:3b85:b0:459:d780:3604 with SMTP id 5b1f17b1804b1-45b689f27ddmr12881755e9.3.1756210706739; Tue, 26 Aug 2025 05:18:26 -0700 (PDT) Received: from oscar-xps.. ([45.128.133.231]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-45b5758a0bfsm149513675e9.20.2025.08.26.05.18.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Aug 2025 05:18:26 -0700 (PDT) From: Oscar Maes To: bacs@librecast.net, brett@librecast.net, kuba@kernel.org Cc: davem@davemloft.net, dsahern@kernel.org, netdev@vger.kernel.org, regressions@lists.linux.dev, stable@vger.kernel.org, Oscar Maes Subject: [PATCH net v2 2/2] selftests: net: add test for destination in broadcast packets Date: Tue, 26 Aug 2025 14:17:50 +0200 Message-Id: <20250826121750.8451-2-oscmaes92@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250826121126-oscmaes92@gmail.com> References: <20250826121126-oscmaes92@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 Add test to check the broadcast ethernet destination field is set correctly. This test sends a broadcast ping, captures it using tcpdump and ensures that all bits of the 6 octet ethernet destination address are correctly set by examining the output capture file. Signed-off-by: Oscar Maes --- Thanks to Brett Sheffield for the initial selftest! --- tools/testing/selftests/net/Makefile | 1 + .../selftests/net/broadcast_ether_dst.sh | 82 +++++++++++++++++++ 2 files changed, 83 insertions(+) create mode 100755 tools/testing/selftests/net/broadcast_ether_dst.sh diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index eef0b8f8a7b0..9bbe1d010f5a 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -116,6 +116,7 @@ TEST_GEN_FILES += skf_net_off TEST_GEN_FILES += tfo TEST_PROGS += tfo_passive.sh TEST_PROGS += broadcast_pmtu.sh +TEST_PROGS += broadcast_ether_dst.sh TEST_PROGS += ipv6_force_forwarding.sh TEST_PROGS += route_hint.sh diff --git a/tools/testing/selftests/net/broadcast_ether_dst.sh b/tools/testing/selftests/net/broadcast_ether_dst.sh new file mode 100755 index 000000000000..865b5c7c8c8a --- /dev/null +++ b/tools/testing/selftests/net/broadcast_ether_dst.sh @@ -0,0 +1,82 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# Author: Brett A C Sheffield +# Author: Oscar Maes +# +# Ensure destination ethernet field is correctly set for +# broadcast packets + +source lib.sh + +CLIENT_IP4="192.168.0.1" +GW_IP4="192.168.0.2" + +setup() { + setup_ns CLIENT_NS SERVER_NS + + ip -net "${SERVER_NS}" link add link1 type veth \ + peer name link0 netns "${CLIENT_NS}" + + ip -net "${CLIENT_NS}" link set link0 up + ip -net "${CLIENT_NS}" addr add "${CLIENT_IP4}"/24 dev link0 + + ip -net "${SERVER_NS}" link set link1 up + + ip -net "${CLIENT_NS}" route add default via "${GW_IP4}" + ip netns exec "${CLIENT_NS}" arp -s "${GW_IP4}" 00:11:22:33:44:55 +} + +cleanup() { + rm -f "${CAPFILE}" + ip -net "${SERVER_NS}" link del link1 + cleanup_ns "${CLIENT_NS}" "${SERVER_NS}" +} + +test_broadcast_ether_dst() { + local rc=0 + CAPFILE=$(mktemp -u cap.XXXXXXXXXX) + + echo "Testing ethernet broadcast destination" + + # start tcpdump listening for icmp + # tcpdump will exit after receiving a single packet + # timeout will kill tcpdump if it is still running after 2s + timeout 2s ip netns exec "${CLIENT_NS}" \ + tcpdump -i link0 -c 1 -w "${CAPFILE}" icmp &> /dev/null & + pid=$! + sleep 0.1 # let tcpdump wake up + + # send broadcast ping + ip netns exec "${CLIENT_NS}" \ + ping -W0.01 -c1 -b 255.255.255.255 &> /dev/null + + # wait for tcpdump for exit after receiving packet + wait "${pid}" + + # compare ethernet destination field to ff:ff:ff:ff:ff:ff + ether_dst=$(tcpdump -r "${CAPFILE}" -tnne 2>/dev/null | \ + awk '{sub(/,/,"",$3); print $3}') + if [[ "${ether_dst}" == "ff:ff:ff:ff:ff:ff" ]]; then + echo "[ OK ]" + rc="${ksft_pass}" + else + echo "[FAIL] expected dst ether addr to be ff:ff:ff:ff:ff:ff," \ + "got ${ether_dst}" + rc="${ksft_fail}" + fi + + return "${rc}" +} + +if [ ! -x "$(command -v tcpdump)" ]; then + echo "SKIP: Could not run test without tcpdump tool" + exit "${ksft_skip}" +fi + +trap cleanup EXIT + +setup +test_broadcast_ether_dst + +exit $? -- 2.39.5