Linux Ethernet Bridging - Apr 2022 - [Bridge] [PATCH RFC net-next 07/13] selftests: forwarding: new test, verify bridge flood flags

On Mon, Apr 11, 2022 at 03:38:31PM +0200, Joachim Wiberg
wrote:
> Test per-port flood control flags of unknown BUM traffic by injecting
> bc/uc/mc on one bridge port and verifying it being forwarded to both
> the bridge itself and another regular bridge port.
> 
> Signed-off-by: Joachim Wiberg <troglobit at gmail.com>
> ---
>  .../testing/selftests/net/forwarding/Makefile |   3 +-
>  .../selftests/net/forwarding/bridge_flood.sh  | 170 ++++++++++++++++++
>  2 files changed, 172 insertions(+), 1 deletion(-)
>  create mode 100755 tools/testing/selftests/net/forwarding/bridge_flood.sh
> 
> diff --git a/tools/testing/selftests/net/forwarding/Makefile
b/tools/testing/selftests/net/forwarding/Makefile
> index ae80c2aef577..873fa61d1ee1 100644
> --- a/tools/testing/selftests/net/forwarding/Makefile
> +++ b/tools/testing/selftests/net/forwarding/Makefile
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0+ OR MIT
>  
> -TEST_PROGS = bridge_igmp.sh \
> +TEST_PROGS = bridge_flood.sh \
> +	bridge_igmp.sh \
>  	bridge_locked_port.sh \
>  	bridge_mdb.sh \
>  	bridge_port_isolation.sh \
> diff --git a/tools/testing/selftests/net/forwarding/bridge_flood.sh
b/tools/testing/selftests/net/forwarding/bridge_flood.sh
> new file mode 100755
> index 000000000000..1966c960d705
> --- /dev/null
> +++ b/tools/testing/selftests/net/forwarding/bridge_flood.sh
> @@ -0,0 +1,170 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Verify per-port flood control flags of unknown BUM traffic.
> +#
> +#                     br0
> +#                    /   \
> +#                  h1     h2
I think the picture is slightly inaccurate. From it I understand that h1
and h2 are bridge ports, but they are stations attached to the real
bridge ports, swp1 and swp2. Maybe it would be good to draw all interfaces.
> +#
> +# We inject bc/uc/mc on h1, toggle the three flood flags for
> +# both br0 and h2, then verify that traffic is flooded as per
> +# the flags, and nowhere else.
> +#
> +#set -x
stray debug line
> +
> +ALL_TESTS="br_flood_unknown_bc_test br_flood_unknown_uc_test
br_flood_unknown_mc_test"
> +NUM_NETIFS=4
> +
> +SRC_MAC="00:de:ad:be:ef:00"
> +GRP_IP4="225.1.2.3"
> +GRP_MAC="01:00:01:c0:ff:ee"
> +GRP_IP6="ff02::42"
> +
> +BC_PKT="ff:ff:ff:ff:ff:ff $SRC_MAC 00:04 48:45:4c:4f"
HELO to you too
> +UC_PKT="02:00:01:c0:ff:ee $SRC_MAC 00:04 48:45:4c:4f"
> +MC_PKT="01:00:5e:01:02:03 $SRC_MAC 08:00 45:00 00:20 c2:10 00:00 ff
11 12:b2 01:02:03:04 e1:01:02:03 04:d2 10:e1 00:0c 6e:84 48:45:4c:4f"
> +
> +# Disable promisc to ensure we only receive flooded frames
> +export TCPDUMP_EXTRA_FLAGS="-pl"
Exporting should be required only for sub-shells, doesn't apply when you
source a script.
> +
> +source lib.sh
> +
> +h1=${NETIFS[p1]}
> +h2=${NETIFS[p3]}
> +swp1=${NETIFS[p2]}
> +swp2=${NETIFS[p4]}
> +
> +#
> +# Port mappings and flood flag pattern to set/detect
> +#
> +declare -A ports=([br0]=br0 [$swp1]=$h1 [$swp2]=$h2)
Maybe you could populate the "ports" and the "flagN" arrays
in the same
order, i.e. bridge first for all?

Also, to be honest, a generic name like "ports" is hard to digest,
especially since you have another generic variable name "iface".
Maybe "brports" and "station" is a little bit more specific?
> +declare -A flag1=([$swp1]=off [$swp2]=off [br0]=off)
> +declare -A flag2=([$swp1]=off [$swp2]=on  [br0]=off)
> +declare -A flag3=([$swp1]=off [$swp2]=on  [br0]=on )
> +declare -A flag4=([$swp1]=off [$swp2]=off [br0]=on )
If it's not too much, maybe these could be called "flags_pass1",
etc.
Again, it was a bit hard to digest on first read.
> +
> +switch_create()
> +{
> +	ip link add dev br0 type bridge
> +
> +	for port in ${!ports[@]}; do
> +		[ "$port" != "br0" ] && ip link set dev
$port master br0
> +		ip link set dev $port up
> +	done
> +}
> +
> +switch_destroy()
> +{
> +	for port in ${!ports[@]}; do
> +		ip link set dev $port down
> +	done
> +	ip link del dev br0
> +}
> +
> +setup_prepare()
> +{
> +	vrf_prepare
> +
> +	let i=1
> +	for iface in ${ports[@]}; do
> +		[ "$iface" = "br0" ] && continue
> +		simple_if_init $iface 192.0.2.$i/24 2001:db8:1::$i/64
> +		let i=$((i + 1))
> +	done
> +
> +	switch_create
> +}
> +
> +cleanup()
> +{
> +	pre_cleanup
> +	switch_destroy
> +
> +	let i=1
> +	for iface in ${ports[@]}; do
> +		[ "$iface" = "br0" ] && continue
> +		simple_if_fini $iface 192.0.2.$i/24 2001:db8:1::$i/64
> +		let i=$((i + 1))
> +	done
> +
> +	vrf_cleanup
> +}
> +
> +do_flood_unknown()
> +{
> +	local type=$1
> +	local pass=$2
> +	local flag=$3
> +	local pkt=$4
> +	local -n flags=$5
I find it slightly less confusing if "flag" and "flags" are
next to each
other in the parameter list, since they're related.
> +
> +	RET=0
> +	for port in ${!ports[@]}; do
> +		if [ "$port" = "br0" ]; then
> +			self="self"
> +		else
> +			self=""
> +		fi
> +		bridge link set dev $port $flag ${flags[$port]} $self
> +		check_err $? "Failed setting $port $flag ${flags[$port]}"
> +	done
> +
> +	for iface in ${ports[@]}; do
> +		tcpdump_start $iface
> +	done
> +
> +	$MZ -q $h1 "$pkt"
> +	sleep 1
> +
> +	for iface in ${ports[@]}; do
> +		tcpdump_stop $iface
> +	done
> +
> +	for port in ${!ports[@]}; do
> +		iface=${ports[$port]}
> +
> +#		echo "Dumping PCAP from $iface, expecting ${flags[$port]}:"
> +#		tcpdump_show $iface
Do something about the commented lines.
> +		tcpdump_show $iface |grep -q "$SRC_MAC"
Space between pipe and grep.
> +		rc=$?
> +
> +		check_err_fail "${flags[$port]} = on"  $? "failed
flooding from $h1 to port $port"
I think the "failed" word here is superfluous, since check_err_fail
already says "$what succeeded, but should have failed".
> +		check_err_fail "${flags[$port]} = off" $? "flooding from
$h1 to port $port"
> +	done
> +
> +	log_test "flood unknown $type pass $pass/4"
> +}
> +
> +br_flood_unknown_bc_test()
> +{
> +	do_flood_unknown BC 1 bcast_flood "$BC_PKT" flag1
> +	do_flood_unknown BC 2 bcast_flood "$BC_PKT" flag2
> +	do_flood_unknown BC 3 bcast_flood "$BC_PKT" flag3
> +	do_flood_unknown BC 4 bcast_flood "$BC_PKT" flag4
> +}
> +
> +br_flood_unknown_uc_test()
> +{
> +	do_flood_unknown UC 1 flood "$UC_PKT" flag1
> +	do_flood_unknown UC 2 flood "$UC_PKT" flag2
> +	do_flood_unknown UC 3 flood "$UC_PKT" flag3
> +	do_flood_unknown UC 4 flood "$UC_PKT" flag4
> +}
> +
> +br_flood_unknown_mc_test()
> +{
> +	do_flood_unknown MC 1 mcast_flood "$MC_PKT" flag1
> +	do_flood_unknown MC 2 mcast_flood "$MC_PKT" flag2
> +	do_flood_unknown MC 3 mcast_flood "$MC_PKT" flag3
> +	do_flood_unknown MC 4 mcast_flood "$MC_PKT" flag4
> +}
> +
> +trap cleanup EXIT
> +
> +setup_prepare
> +setup_wait
> +
> +tests_run
> +
> +exit $EXIT_STATUS
> -- 
> 2.25.1
>

On Mon, Apr 11, 2022 at 20:21, Vladimir Oltean <vladimir.oltean at
nxp.com> wrote:
> On Mon, Apr 11, 2022 at 03:38:31PM +0200, Joachim Wiberg wrote:
>> +# Verify per-port flood control flags of unknown BUM traffic.
>> +#
>> +#                     br0
>> +#                    /   \
>> +#                  h1     h2
>
> I think the picture is slightly inaccurate. From it I understand that h1
> and h2 are bridge ports, but they are stations attached to the real
> bridge ports, swp1 and swp2. Maybe it would be good to draw all interfaces.
Hmm, yeah either that or drop it entirely.  I sort of assumed everyone
knew about the h<-[veth]->swp (or actual cable) setup, but you're
right
this is a bit unclear.  Me and Tobias have internally used h<-->p (for
host<-->bridge-port) and other similar nomenclature.  Finding a good
name that fits easily, and is still readable, in ASCII drawings is hard.
I'll give it a go in the next drop, thanks!
>> +#set -x
> stray debug line
thx
>> +# Disable promisc to ensure we only receive flooded frames
>> +export TCPDUMP_EXTRA_FLAGS="-pl"
> Exporting should be required only for sub-shells, doesn't apply when
you
> source a script.
Ah thanks, will fix!
>> +# Port mappings and flood flag pattern to set/detect
>> +declare -A ports=([br0]=br0 [$swp1]=$h1 [$swp2]=$h2)
> Maybe you could populate the "ports" and the "flagN"
arrays in the same
> order, i.e. bridge first for all?
Good point, thanks!
> Also, to be honest, a generic name like "ports" is hard to
digest,
> especially since you have another generic variable name "iface".
> Maybe "brports" and "station" is a little bit more
specific?
Is there a common naming standard between bridge tests, or is it more
important to be consistent the test overview (test heading w/ picture)?

Anyway, I'll have a look at the naming for the next drop.
>> +declare -A flag1=([$swp1]=off [$swp2]=off [br0]=off)
>> +declare -A flag2=([$swp1]=off [$swp2]=on  [br0]=off)
>> +declare -A flag3=([$swp1]=off [$swp2]=on  [br0]=on )
>> +declare -A flag4=([$swp1]=off [$swp2]=off [br0]=on )
> If it's not too much, maybe these could be called
"flags_pass1", etc.
> Again, it was a bit hard to digest on first read.
More like flags_pass_fail, but since its the flooding flags, maybe
flood_patternN would be better?
>> +do_flood_unknown()
>> +{
>> +	local type=$1
>> +	local pass=$2
>> +	local flag=$3
>> +	local pkt=$4
>> +	local -n flags=$5
> I find it slightly less confusing if "flag" and "flags"
are next to each
> other in the parameter list, since they're related.
Hmm, OK.
>> +#		echo "Dumping PCAP from $iface, expecting
${flags[$port]}:"
>> +#		tcpdump_show $iface
> Do something about the commented lines.
Oups, thanks!
>> +		tcpdump_show $iface |grep -q "$SRC_MAC"
> Space between pipe and grep.
Will fix!
>> +		check_err_fail "${flags[$port]} = on"  $? "failed
flooding from $h1 to port $port"
> I think the "failed" word here is superfluous, since
check_err_fail
> already says "$what succeeded, but should have failed".
Ah, good point!

Thank you for the review! <3

 /J