[PATCH v3 net-next 5/5] selftests: openvswitch: add ct-nat test case with ipv4

From: Aaron Conole
Date: Tue Aug 01 2023 - 17:24:07 EST


Building on the previous work, add a very simplistic NAT case
using ipv4. This just tests dnat transformation

Signed-off-by: Aaron Conole <aconole@xxxxxxxxxx>
---
NOTE: A number of lines flag the line-length checkpatch
warning, but there didnt seem to be a really good
way of breaking the lines smaller.

.../selftests/net/openvswitch/openvswitch.sh | 64 +++++++++++++++++++
.../selftests/net/openvswitch/ovs-dpctl.py | 62 ++++++++++++++++++
2 files changed, 126 insertions(+)

diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh
index 40a66c72af0f0..dced4f612a78c 100755
--- a/tools/testing/selftests/net/openvswitch/openvswitch.sh
+++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh
@@ -14,6 +14,7 @@ tests="
arp_ping eth-arp: Basic arp ping between two NS
ct_connect_v4 ip4-ct-xon: Basic ipv4 tcp connection using ct
connect_v4 ip4-xon: Basic ipv4 ping between two NS
+ nat_connect_v4 ip4-nat-xon: Basic ipv4 tcp connection via NAT
netlink_checks ovsnl: validate netlink attrs and settings
upcall_interfaces ovs: test the upcall interfaces"

@@ -300,6 +301,69 @@ test_connect_v4 () {
return 0
}

+# nat_connect_v4 test
+# - client has 1500 byte MTU
+# - server has 1500 byte MTU
+# - use ICMP to ping in each direction
+# - only allow CT state stuff to pass through new in c -> s
+test_nat_connect_v4 () {
+ which nc >/dev/null 2>/dev/null || return $ksft_skip
+
+ sbx_add "test_nat_connect_v4" || return $?
+
+ ovs_add_dp "test_nat_connect_v4" nat4 || return 1
+ info "create namespaces"
+ for ns in client server; do
+ ovs_add_netns_and_veths "test_nat_connect_v4" "nat4" "$ns" \
+ "${ns:0:1}0" "${ns:0:1}1" || return 1
+ done
+
+ ip netns exec client ip addr add 172.31.110.10/24 dev c1
+ ip netns exec client ip link set c1 up
+ ip netns exec server ip addr add 172.31.110.20/24 dev s1
+ ip netns exec server ip link set s1 up
+
+ ip netns exec client ip route add default via 172.31.110.20
+
+ ovs_add_flow "test_nat_connect_v4" nat4 \
+ 'in_port(1),eth(),eth_type(0x0806),arp()' '2' || return 1
+ ovs_add_flow "test_nat_connect_v4" nat4 \
+ 'in_port(2),eth(),eth_type(0x0806),arp()' '1' || return 1
+ ovs_add_flow "test_nat_connect_v4" nat4 \
+ "ct_state(-trk),in_port(1),eth(),eth_type(0x0800),ipv4(dst=192.168.0.20)" \
+ "ct(commit,nat(dst=172.31.110.20)),recirc(0x1)"
+ ovs_add_flow "test_nat_connect_v4" nat4 \
+ "ct_state(-trk),in_port(2),eth(),eth_type(0x0800),ipv4()" \
+ "ct(commit,nat),recirc(0x2)"
+
+ ovs_add_flow "test_nat_connect_v4" nat4 \
+ "recirc_id(0x1),ct_state(+trk-inv),in_port(1),eth(),eth_type(0x0800),ipv4()" "2"
+ ovs_add_flow "test_nat_connect_v4" nat4 \
+ "recirc_id(0x2),ct_state(+trk-inv),in_port(2),eth(),eth_type(0x0800),ipv4()" "1"
+
+ # do a ping
+ ovs_sbx "test_nat_connect_v4" ip netns exec client ping 192.168.0.20 -c 3 || return 1
+
+ # create an echo server in 'server'
+ echo "server" | \
+ ovs_netns_spawn_daemon "test_nat_connect_v4" "server" \
+ nc -lvnp 4443
+ ovs_sbx "test_nat_connect_v4" ip netns exec client nc -i 1 -zv 192.168.0.20 4443 || return 1
+
+ # Now test in the other direction (should fail)
+ echo "client" | \
+ ovs_netns_spawn_daemon "test_nat_connect_v4" "client" \
+ nc -lvnp 4443
+ ovs_sbx "test_nat_connect_v4" ip netns exec client nc -i 1 -zv 172.31.110.10 4443
+ if [ $? == 0 ]; then
+ info "connect to client was successful"
+ return 1
+ fi
+
+ info "done..."
+ return 0
+}
+
# netlink_validation
# - Create a dp
# - check no warning with "old version" simulation
diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
index 1a3dc3762361b..fbdac15e31344 100644
--- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
+++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
@@ -530,6 +530,68 @@ class ovsactions(nla):
else:
ctact["attrs"].append([scan[1], None])
actstr = actstr[strspn(actstr, ", ") :]
+ # it seems strange to put this here, but nat() is a complex
+ # sub-action and this lets it sit anywhere in the ct() action
+ if actstr.startswith("nat"):
+ actstr = actstr[3:]
+ natact = ovsactions.ctact.natattr()
+
+ if actstr.startswith("("):
+ t = None
+ actstr = actstr[1:]
+ if actstr.startswith("src"):
+ t = "OVS_NAT_ATTR_SRC"
+ actstr = actstr[3:]
+ elif actstr.startswith("dst"):
+ t = "OVS_NAT_ATTR_DST"
+ actstr = actstr[3:]
+
+ actstr, ip_block_min = parse_extract_field(
+ actstr, "=", "([0-9a-fA-F\.]+)", str, False
+ )
+ actstr, ip_block_max = parse_extract_field(
+ actstr, "-", "([0-9a-fA-F\.]+)", str, False
+ )
+
+ actstr, proto_min = parse_extract_field(
+ actstr, ":", "(\d+)", int, False
+ )
+ actstr, proto_max = parse_extract_field(
+ actstr, "-", "(\d+)", int, False
+ )
+
+ if t is not None:
+ natact["attrs"].append([t, None])
+
+ if ip_block_min is not None:
+ natact["attrs"].append(
+ ["OVS_NAT_ATTR_IP_MIN", ip_block_min]
+ )
+ if ip_block_max is not None:
+ natact["attrs"].append(
+ ["OVS_NAT_ATTR_IP_MAX", ip_block_max]
+ )
+ if proto_min is not None:
+ natact["attrs"].append(
+ ["OVS_NAT_ATTR_PROTO_MIN", proto_min]
+ )
+ if proto_max is not None:
+ natact["attrs"].append(
+ ["OVS_NAT_ATTR_PROTO_MAX", proto_max]
+ )
+
+ for natscan in (
+ ("persistent", "OVS_NAT_ATTR_PERSISTENT"),
+ ("hash", "OVS_NAT_ATTR_PROTO_HASH"),
+ ("random", "OVS_NAT_ATTR_PROTO_RANDOM"),
+ ):
+ if actstr.startswith(natscan[0]):
+ actstr = actstr[len(natscan[0]) :]
+ natact["attrs"].append([natscan[1], None])
+ actstr = actstr[strspn(actstr, ", ") :]
+
+ ctact["attrs"].append(["OVS_CT_ATTR_NAT", natact])
+ actstr = actstr[strspn(actstr, ",) ") :]

self["attrs"].append(["OVS_ACTION_ATTR_CT", ctact])
parsed = True
--
2.40.1