selftests: forwarding: Add libs for gretap mirror testing

To simplify implementation of mirror-to-gretap tests, extend lib.sh with
several new functions that might potentially be useful more
broadly (although right now the mirroring tests will be the only
client).

Also add mirror_lib.sh with code useful for mirroring tests,
mirror_gre_lib.sh with code specifically useful for mirror-to-gretap
tests, and mirror_gre_topo.sh that primes a given test with a good
baseline topology that the test can then tweak to its liking.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/forwarding/lib.sh

@@ -321,6 +321,25 @@ simple_if_fini()
 	vrf_destroy $vrf_name
 }
 
+tunnel_create()
+{
+	local name=$1; shift
+	local type=$1; shift
+	local local=$1; shift
+	local remote=$1; shift
+
+	ip link add name $name type $type \
+	   local $local remote $remote "$@"
+	ip link set dev $name up
+}
+
+tunnel_destroy()
+{
+	local name=$1; shift
+
+	ip link del dev $name
+}
+
 master_name_get()
 {
 	local if_name=$1
@@ -335,6 +354,15 @@ link_stats_tx_packets_get()
        ip -j -s link show dev $if_name | jq '.[]["stats64"]["tx"]["packets"]'
 }
 
+tc_rule_stats_get()
+{
+	local dev=$1; shift
+	local pref=$1; shift
+
+	tc -j -s filter show dev $dev ingress pref $pref |
+	jq '.[1].options.actions[].stats.packets'
+}
+
 mac_get()
 {
 	local if_name=$1
@@ -381,6 +409,74 @@ tc_offload_check()
 	return 0
 }
 
+slow_path_trap_install()
+{
+	local dev=$1; shift
+	local direction=$1; shift
+
+	if [ "${tcflags/skip_hw}" != "$tcflags" ]; then
+		# For slow-path testing, we need to install a trap to get to
+		# slow path the packets that would otherwise be switched in HW.
+		tc filter add dev $dev $direction pref 1 \
+		   flower skip_sw action trap
+	fi
+}
+
+slow_path_trap_uninstall()
+{
+	local dev=$1; shift
+	local direction=$1; shift
+
+	if [ "${tcflags/skip_hw}" != "$tcflags" ]; then
+		tc filter del dev $dev $direction pref 1 flower skip_sw
+	fi
+}
+
+__icmp_capture_add_del()
+{
+	local add_del=$1; shift
+	local pref=$1; shift
+	local vsuf=$1; shift
+	local tundev=$1; shift
+	local filter=$1; shift
+
+	tc filter $add_del dev "$tundev" ingress \
+	   proto ip$vsuf pref $pref \
+	   flower ip_proto icmp$vsuf $filter \
+	   action pass
+}
+
+icmp_capture_install()
+{
+	__icmp_capture_add_del add 100 "" "$@"
+}
+
+icmp_capture_uninstall()
+{
+	__icmp_capture_add_del del 100 "" "$@"
+}
+
+icmp6_capture_install()
+{
+	__icmp_capture_add_del add 100 v6 "$@"
+}
+
+icmp6_capture_uninstall()
+{
+	__icmp_capture_add_del del 100 v6 "$@"
+}
+
+matchall_sink_create()
+{
+	local dev=$1; shift
+
+	tc qdisc add dev $dev clsact
+	tc filter add dev $dev ingress \
+	   pref 10000 \
+	   matchall \
+	   action drop
+}
+
 ##############################################################################
 # Tests
 

tools/testing/selftests/net/forwarding/mirror_gre_lib.sh

+# SPDX-License-Identifier: GPL-2.0
+
+do_test_span_gre_dir_ips()
+{
+	local expect=$1; shift
+	local tundev=$1; shift
+	local direction=$1; shift
+	local ip1=$1; shift
+	local ip2=$1; shift
+
+	icmp_capture_install h3-$tundev
+	mirror_test v$h1 $ip1 $ip2 h3-$tundev 100 $expect
+	mirror_test v$h2 $ip2 $ip1 h3-$tundev 100 $expect
+	icmp_capture_uninstall h3-$tundev
+}
+
+quick_test_span_gre_dir_ips()
+{
+	do_test_span_gre_dir_ips 10 "$@"
+}
+
+fail_test_span_gre_dir_ips()
+{
+	do_test_span_gre_dir_ips 0 "$@"
+}
+
+test_span_gre_dir_ips()
+{
+	local tundev=$1; shift
+	local direction=$1; shift
+	local forward_type=$1; shift
+	local backward_type=$1; shift
+	local ip1=$1; shift
+	local ip2=$1; shift
+
+	quick_test_span_gre_dir_ips "$tundev" "$direction" "$ip1" "$ip2"
+
+	icmp_capture_install h3-$tundev "type $forward_type"
+	mirror_test v$h1 $ip1 $ip2 h3-$tundev 100 10
+	icmp_capture_uninstall h3-$tundev
+
+	icmp_capture_install h3-$tundev "type $backward_type"
+	mirror_test v$h2 $ip2 $ip1 h3-$tundev 100 10
+	icmp_capture_uninstall h3-$tundev
+}
+
+full_test_span_gre_dir_ips()
+{
+	local tundev=$1; shift
+	local direction=$1; shift
+	local forward_type=$1; shift
+	local backward_type=$1; shift
+	local what=$1; shift
+	local ip1=$1; shift
+	local ip2=$1; shift
+
+	RET=0
+
+	mirror_install $swp1 $direction $tundev "matchall $tcflags"
+	test_span_gre_dir_ips "$tundev" "$direction" "$forward_type" \
+			      "$backward_type" "$ip1" "$ip2"
+	mirror_uninstall $swp1 $direction
+
+	log_test "$direction $what ($tcflags)"
+}
+
+quick_test_span_gre_dir()
+{
+	quick_test_span_gre_dir_ips "$@" 192.0.2.1 192.0.2.2
+}
+
+fail_test_span_gre_dir()
+{
+	fail_test_span_gre_dir_ips "$@" 192.0.2.1 192.0.2.2
+}
+
+test_span_gre_dir()
+{
+	test_span_gre_dir_ips "$@" 192.0.2.1 192.0.2.2
+}
+
+full_test_span_gre_dir()
+{
+	full_test_span_gre_dir_ips "$@" 192.0.2.1 192.0.2.2
+}

tools/testing/selftests/net/forwarding/mirror_gre_topo_lib.sh

+# SPDX-License-Identifier: GPL-2.0
+
+# This is the standard topology for testing mirroring to gretap and ip6gretap
+# netdevices. The tests that use it tweak it in one way or another--importantly,
+# $swp3 and $h3 need to have addresses set up.
+#
+#   +---------------------+                             +---------------------+
+#   | H1                  |                             |                  H2 |
+#   |     + $h1           |                             |           $h2 +     |
+#   |     | 192.0.2.1/28  |                             |  192.0.2.2/28 |     |
+#   +-----|---------------+                             +---------------|-----+
+#         |                                                             |
+#   +-----|-------------------------------------------------------------|-----+
+#   | SW  o--> mirror                                                   |     |
+#   | +---|-------------------------------------------------------------|---+ |
+#   | |   + $swp1                    BR                           $swp2 +   | |
+#   | +---------------------------------------------------------------------+ |
+#   |                                                                         |
+#   |     + $swp3               + gt6 (ip6gretap)      + gt4 (gretap)         |
+#   |     |                     : loc=2001:db8:2::1    : loc=192.0.2.129      |
+#   |     |                     : rem=2001:db8:2::2    : rem=192.0.2.130      |
+#   |     |                     : ttl=100              : ttl=100              |
+#   |     |                     : tos=inherit          : tos=inherit          |
+#   |     |                     :                      :                      |
+#   +-----|---------------------:----------------------:----------------------+
+#         |                     :                      :
+#   +-----|---------------------:----------------------:----------------------+
+#   | H3  + $h3                 + h3-gt6 (ip6gretap)   + h3-gt4 (gretap)      |
+#   |                             loc=2001:db8:2::2      loc=192.0.2.130      |
+#   |                             rem=2001:db8:2::1      rem=192.0.2.129      |
+#   |                             ttl=100                ttl=100              |
+#   |                             tos=inherit            tos=inherit          |
+#   |                                                                         |
+#   +-------------------------------------------------------------------------+
+
+mirror_gre_topo_h1_create()
+{
+	simple_if_init $h1 192.0.2.1/28
+}
+
+mirror_gre_topo_h1_destroy()
+{
+	simple_if_fini $h1 192.0.2.1/28
+}
+
+mirror_gre_topo_h2_create()
+{
+	simple_if_init $h2 192.0.2.2/28
+}
+
+mirror_gre_topo_h2_destroy()
+{
+	simple_if_fini $h2 192.0.2.2/28
+}
+
+mirror_gre_topo_h3_create()
+{
+	simple_if_init $h3
+
+	tunnel_create h3-gt4 gretap 192.0.2.130 192.0.2.129
+	ip link set h3-gt4 vrf v$h3
+	matchall_sink_create h3-gt4
+
+	tunnel_create h3-gt6 ip6gretap 2001:db8:2::2 2001:db8:2::1
+	ip link set h3-gt6 vrf v$h3
+	matchall_sink_create h3-gt6
+}
+
+mirror_gre_topo_h3_destroy()
+{
+	tunnel_destroy h3-gt6
+	tunnel_destroy h3-gt4
+
+	simple_if_fini $h3
+}
+
+mirror_gre_topo_switch_create()
+{
+	ip link set dev $swp3 up
+
+	ip link add name br1 type bridge vlan_filtering 1
+	ip link set dev br1 up
+
+	ip link set dev $swp1 master br1
+	ip link set dev $swp1 up
+
+	ip link set dev $swp2 master br1
+	ip link set dev $swp2 up
+
+	tunnel_create gt4 gretap 192.0.2.129 192.0.2.130 \
+		      ttl 100 tos inherit
+
+	tunnel_create gt6 ip6gretap 2001:db8:2::1 2001:db8:2::2 \
+		      ttl 100 tos inherit allow-localremote
+
+	tc qdisc add dev $swp1 clsact
+}
+
+mirror_gre_topo_switch_destroy()
+{
+	tc qdisc del dev $swp1 clsact
+
+	tunnel_destroy gt6
+	tunnel_destroy gt4
+
+	ip link set dev $swp1 down
+	ip link set dev $swp2 down
+	ip link del dev br1
+
+	ip link set dev $swp3 down
+}
+
+mirror_gre_topo_create()
+{
+	mirror_gre_topo_h1_create
+	mirror_gre_topo_h2_create
+	mirror_gre_topo_h3_create
+
+	mirror_gre_topo_switch_create
+}
+
+mirror_gre_topo_destroy()
+{
+	mirror_gre_topo_switch_destroy
+
+	mirror_gre_topo_h3_destroy
+	mirror_gre_topo_h2_destroy
+	mirror_gre_topo_h1_destroy
+}

tools/testing/selftests/net/forwarding/mirror_lib.sh

+# SPDX-License-Identifier: GPL-2.0
+
+mirror_install()
+{
+	local from_dev=$1; shift
+	local direction=$1; shift
+	local to_dev=$1; shift
+	local filter=$1; shift
+
+	tc filter add dev $from_dev $direction \
+	   pref 1000 $filter \
+	   action mirred egress mirror dev $to_dev
+}
+
+mirror_uninstall()
+{
+	local from_dev=$1; shift
+	local direction=$1; shift
+
+	tc filter del dev $swp1 $direction pref 1000
+}
+
+mirror_test()
+{
+	local vrf_name=$1; shift
+	local sip=$1; shift
+	local dip=$1; shift
+	local dev=$1; shift
+	local pref=$1; shift
+	local expect=$1; shift
+
+	local t0=$(tc_rule_stats_get $dev $pref)
+	ip vrf exec $vrf_name \
+	   ${PING} ${sip:+-I $sip} $dip -c 10 -i 0.1 -w 2 &> /dev/null
+	local t1=$(tc_rule_stats_get $dev $pref)
+	local delta=$((t1 - t0))
+	# Tolerate a couple stray extra packets.
+	((expect <= delta && delta <= expect + 2))
+	check_err $? "Expected to capture $expect packets, got $delta."
+}