[PATCH net-next v14 7/7] bonding: Selftest and documentation for the arp_ip_target parameter.

[David Wilder <wilder@us.ibm.com>]

Selftest provided as a functional test for the arp_ip_target parameter
both with and without user supplied vlan tags. Bonding documentation
has been updated for the arp_ip_target option.

Signed-off-by: David Wilder <wilder@us.ibm.com>
---
 Documentation/networking/bonding.rst          |  11 +
 .../selftests/drivers/net/bonding/Makefile    |   1 +
 .../drivers/net/bonding/bond-arp-ip-target.sh | 204 ++++++++++++++++++
 3 files changed, 216 insertions(+)
 create mode 100755 tools/testing/selftests/drivers/net/bonding/bond-arp-ip-target.sh

diff --git a/Documentation/networking/bonding.rst b/Documentation/networking/bonding.rst
index e700bf1d095c..08a3191a0322 100644
--- a/Documentation/networking/bonding.rst
+++ b/Documentation/networking/bonding.rst
@@ -330,6 +330,17 @@ arp_ip_target
 	maximum number of targets that can be specified is 16.  The
 	default value is no IP addresses.
 
+        When an arp_ip_target is configured the bonding driver will
+        attempt to automatically determine what vlans the arp probe will
+        pass through. This process of gathering vlan tags is required
+        for the arp probe to be sent. However, in some configurations
+        this process may fail. In these cases you may manually
+        supply a list of vlan tags. To specify a list of vlan tags
+        append the ipv4 address with [tag1/tag2...]. For example:
+        arp_ip_target=10.0.0.1[10]. If you simply need to disable the
+        vlan discovery process you may provide an empty list, for example:
+        arp_ip_target=10.0.0.1[].
+
 ns_ip6_target
 
 	Specifies the IPv6 addresses to use as IPv6 monitoring peers when
diff --git a/tools/testing/selftests/drivers/net/bonding/Makefile b/tools/testing/selftests/drivers/net/bonding/Makefile
index 402d4ee84f2e..b9594790e6df 100644
--- a/tools/testing/selftests/drivers/net/bonding/Makefile
+++ b/tools/testing/selftests/drivers/net/bonding/Makefile
@@ -3,6 +3,7 @@
 
 TEST_PROGS := \
 	bond-arp-interval-causes-panic.sh \
+	bond-arp-ip-target.sh \
 	bond-break-lacpdu-tx.sh \
 	bond-eth-type-change.sh \
 	bond-lladdr-target.sh \
diff --git a/tools/testing/selftests/drivers/net/bonding/bond-arp-ip-target.sh b/tools/testing/selftests/drivers/net/bonding/bond-arp-ip-target.sh
new file mode 100755
index 000000000000..9e3ecd8c2ced
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/bonding/bond-arp-ip-target.sh
@@ -0,0 +1,204 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test bonding arp_ip_target.
+# Topology for Bond mode 1,5,6 testing
+#
+#  +-------------------------+
+#  |                         | Server
+#  |        bond0.10.20      | 192.20.2.1/24
+#  |            |            |
+#  |         bond0.10        | 192.10.2.1/24
+#  |            |            |
+#  |          bond0          | 192.0.2.1/24
+#  |            |            |
+#  |            +            |
+#  |      eth0  |  eth1      |
+#  |        +---+---+        |
+#  |        |       |        |
+#  +-------------------------+
+#           |       |
+#  +-------------------------+
+#  |        |       |        |
+#  |    +---+-------+---+    |  Gateway
+#  |    |      br0      |    |
+#  |    +-------+-------+    |
+#  |            |            |
+#  +-------------------------+
+#               |
+#  +-------------------------+
+#  |            |            |  Client
+#  |          eth0           | 192.0.0.2/24
+#  |            |            |
+#  |         eth0.10         | 192.10.10.2/24
+#  |            |            |
+#  |        eth0.10.20       | 192.20.20.2/24
+#  +-------------------------+
+
+# shellcheck disable=SC2317
+
+lib_dir=$(dirname "$0")
+
+# shellcheck source=/dev/null # Ignore source warning.
+source "${lib_dir}"/bond_topo_2d1c.sh
+
+# shellcheck disable=SC2154 # Ignore unassigned referenced warning.
+echo "${c_ns}" "${s_ns}" > /dev/null
+
+DEBUG=${DEBUG:-0}
+test "${DEBUG}" -ne 0 && set -x
+
+# vlan subnets
+c_ip4="192.0.2.10"
+c_ip4v10="192.10.2.10"
+c_ip4v20="192.20.2.10"
+
+export ALL_TESTS="
+	no_vlan_hints
+	with_vlan_hints
+"
+
+# Build stacked vlans on top of an interface.
+stack_vlans()
+{
+	RET=0
+	local interface="$1"
+	local ns=$2
+	local last="$interface"
+	local tags="10 20"
+
+	if ! ip -n "${ns}" link show "${interface}" > /dev/null; then
+		RET=1
+		msg="Failed to create ${interface}"
+		return 1
+	fi
+
+	if [ "$ns" == "${s_ns}" ]; then host=1; else host=10;fi
+
+	for tag in $tags; do
+		ip -n "${ns}" link add link "$last" name "$last"."$tag" type vlan id "$tag"
+		ip -n "${ns}" address add 192."$tag".2."$host"/24 dev "$last"."$tag"
+		ip -n "${ns}" link set up dev "$last"."$tag"
+		last=$last.$tag
+	done
+}
+
+wait_for_arp_request()
+{
+	local target=$1
+	local ip
+	local interface
+
+	ip=$(echo "${target}" | awk -F "[" '{print $1}')
+	interface="$(ip -n "${c_ns}" -br addr show | grep "${ip}" | awk -F @ '{print $1}')"
+
+	tc -n "${c_ns}" qdisc add dev "${interface}" clsact
+	tc -n "${c_ns}" filter add dev "${interface}" ingress protocol arp \
+	handle 101 flower skip_hw arp_op request arp_tip "${ip}" action pass
+
+	slowwait_for_counter 5 5 tc_rule_handle_stats_get \
+		"dev ${interface} ingress" 101 ".packets" "-n ${c_ns}" &> /dev/null || RET=1
+
+	tc -n "${c_ns}" filter del dev "${interface}" ingress
+	tc -n "${c_ns}" qdisc del dev "${interface}" clsact
+
+	if [ "$RET" -ne 0 ]; then
+		msg="Arp probe not received by ${interface}"
+		return 1
+	fi
+}
+
+# Check for link flapping.
+# First verify the arp requests are being received
+# by the target.  Then verify that the Link Failure
+# Counts are not increasing over time.
+# Arp probes are sent every 100ms, two probes must
+# be missed to trigger a slave failure. A one second
+# wait should be sufficient.
+check_failure_count()
+{
+	local bond=$1
+	local target=$2
+	local proc_file=/proc/net/bonding/${bond}
+
+	wait_for_arp_request "${target}" || return 1
+
+	LinkFailureCount1=$(ip netns exec "${s_ns}" grep -F "Link Failure Count" "${proc_file}" \
+	| awk -F: '{ sum += $2 } END { print sum }')
+	sleep 1
+	LinkFailureCount2=$(ip netns exec "${s_ns}" grep -F "Link Failure Count" "${proc_file}" \
+	| awk -F: '{ sum += $2 } END { print sum }')
+
+	[ "$LinkFailureCount1" != "$LinkFailureCount2" ] && RET=1
+}
+
+setup_bond_topo()
+{
+	setup_prepare
+	setup_wait
+	stack_vlans bond0 "${s_ns}"
+	stack_vlans eth0 "${c_ns}"
+}
+
+skip_with_vlan_hints()
+{
+	# check if iproute supports arp_ip_target with vlans option.
+	if ! ip -n "${s_ns}" link add bond2 type bond arp_ip_target 10.0.0.1[10]; then
+		ip -n "${s_ns}" link del bond2 2> /dev/null
+		return 0
+	fi
+	return 1
+}
+
+no_vlan_hints()
+{
+	RET=0
+	local targets="${c_ip4} ${c_ip4v10} ${c_ip4v20}"
+	local target
+	msg=""
+
+	for target in $targets; do
+		bond_reset "mode $mode arp_interval 100 arp_ip_target ${target}"
+		stack_vlans bond0 "${s_ns}"
+		if [ "$RET" -ne 0 ]; then
+			log_test "no_vlan_hints" "${msg}"
+			return
+		fi
+		check_failure_count bond0 "${target}"
+		log_test "arp_ip_target=${target} ${msg}"
+	done
+}
+
+with_vlan_hints()
+{
+	RET=0
+	local targets="${c_ip4}[] ${c_ip4v10}[10] ${c_ip4v20}[10/20]"
+	local target
+	msg=""
+
+	if skip_with_vlan_hints; then
+		log_test_skip "skip_with_vlan_hints" \
+		"Installed iproute doesn't support extended arp_ip_target options."
+		return 0
+	fi
+
+	for target in $targets; do
+		bond_reset "mode $mode arp_interval 100 arp_ip_target ${target}"
+		stack_vlans bond0 "${s_ns}"
+		if [ "$RET" -ne 0 ]; then
+			log_test "no_vlan_hints" "${msg}"
+			return
+		fi
+		check_failure_count bond0 "${target}"
+		log_test "arp_ip_target=${target} ${msg}"
+	done
+}
+
+trap cleanup EXIT
+
+mode=active-backup
+
+setup_bond_topo
+tests_run
+
+exit "$EXIT_STATUS"
-- 
2.50.1