selftests: openvswitch: add basic ct test case parsing

Forwarding via ct() action is an important use case for openvswitch, but
generally would require using a full ovs-vswitchd to get working. Add a
ct action parser for basic ct test case.
Signed-off-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Adrian Moreno <amorenoz@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

tools/testing/selftests/net/openvswitch/openvswitch.sh

@@ -12,6 +12,7 @@ TRACING=0
 
 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
 	netlink_checks				ovsnl: validate netlink attrs and settings
 	upcall_interfaces			ovs: test the upcall interfaces"
@@ -193,6 +194,73 @@ test_arp_ping () {
 	return 0
 }
 
+# ct_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_ct_connect_v4 () {
+
+	which nc >/dev/null 2>/dev/null || return $ksft_skip
+
+	sbx_add "test_ct_connect_v4" || return $?
+
+	ovs_add_dp "test_ct_connect_v4" ct4 || return 1
+	info "create namespaces"
+	for ns in client server; do
+		ovs_add_netns_and_veths "test_ct_connect_v4" "ct4" "$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
+
+	# Add forwarding for ARP and ip packets - completely wildcarded
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		'in_port(1),eth(),eth_type(0x0806),arp()' '2' || return 1
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		'in_port(2),eth(),eth_type(0x0806),arp()' '1' || return 1
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		     'ct_state(-trk),eth(),eth_type(0x0800),ipv4()' \
+		     'ct(commit),recirc(0x1)' || return 1
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		     'recirc_id(0x1),ct_state(+trk+new),in_port(1),eth(),eth_type(0x0800),ipv4(src=172.31.110.10)' \
+		     '2' || return 1
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		     'recirc_id(0x1),ct_state(+trk+est),in_port(1),eth(),eth_type(0x0800),ipv4(src=172.31.110.10)' \
+		     '2' || return 1
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		     'recirc_id(0x1),ct_state(+trk+est),in_port(2),eth(),eth_type(0x0800),ipv4(dst=172.31.110.10)' \
+		     '1' || return 1
+	ovs_add_flow "test_ct_connect_v4" ct4 \
+		     'recirc_id(0x1),ct_state(+trk+inv),eth(),eth_type(0x0800),ipv4()' 'drop' || \
+		     return 1
+
+	# do a ping
+	ovs_sbx "test_ct_connect_v4" ip netns exec client ping 172.31.110.20 -c 3 || return 1
+
+	# create an echo server in 'server'
+	echo "server" | \
+		ovs_netns_spawn_daemon "test_ct_connect_v4" "server" \
+				nc -lvnp 4443
+	ovs_sbx "test_ct_connect_v4" ip netns exec client nc -i 1 -zv 172.31.110.20 4443 || return 1
+
+	# Now test in the other direction (should fail)
+	echo "client" | \
+		ovs_netns_spawn_daemon "test_ct_connect_v4" "client" \
+				nc -lvnp 4443
+	ovs_sbx "test_ct_connect_v4" ip netns exec client nc -i 1 -zv 172.31.110.10 4443
+	if [ $? == 0 ]; then
+	   info "ct connect to client was successful"
+	   return 1
+	fi
+
+	info "done..."
+	return 0
+}
+
 # connect_v4 test
 #  - client has 1500 byte MTU
 #  - server has 1500 byte MTU

tools/testing/selftests/net/openvswitch/ovs-dpctl.py

@@ -62,6 +62,15 @@ def macstr(mac):
     return outstr
 
 
+def strcspn(str1, str2):
+    tot = 0
+    for char in str1:
+        if str2.find(char) != -1:
+            return tot
+        tot += 1
+    return tot
+
+
 def strspn(str1, str2):
     tot = 0
     for char in str1:
@@ -496,6 +505,36 @@ class ovsactions(nla):
                     actstr = actstr[strspn(actstr, ", ") :]
                     parsed = True
 
+            if parse_starts_block(actstr, "ct(", False):
+                actstr = actstr[len("ct(") :]
+                ctact = ovsactions.ctact()
+
+                for scan in (
+                    ("commit", "OVS_CT_ATTR_COMMIT", None),
+                    ("force_commit", "OVS_CT_ATTR_FORCE_COMMIT", None),
+                    ("zone", "OVS_CT_ATTR_ZONE", int),
+                    ("mark", "OVS_CT_ATTR_MARK", int),
+                    ("helper", "OVS_CT_ATTR_HELPER", lambda x, y: str(x)),
+                    ("timeout", "OVS_CT_ATTR_TIMEOUT", lambda x, y: str(x)),
+                ):
+                    if actstr.startswith(scan[0]):
+                        actstr = actstr[len(scan[0]) :]
+                        if scan[2] is not None:
+                            if actstr[0] != "=":
+                                raise ValueError("Invalid ct attr")
+                            actstr = actstr[1:]
+                            pos = strcspn(actstr, ",)")
+                            datum = scan[2](actstr[:pos], 0)
+                            ctact["attrs"].append([scan[1], datum])
+                            actstr = actstr[pos:]
+                        else:
+                            ctact["attrs"].append([scan[1], None])
+                        actstr = actstr[strspn(actstr, ", ") :]
+
+                self["attrs"].append(["OVS_ACTION_ATTR_CT", ctact])
+                parsed = True
+
+            actstr = actstr[strspn(actstr, "), ") :]
             if not parsed:
                 raise ValueError("Action str: '%s' not supported" % actstr)