NAT44: fix nat_not_translate_output_feature for ICMP (VPP-1191)

Change-Id: I1552e1418b704fdf1f1fa2c0174313b9b82a37a3
Signed-off-by: Matus Fabian <matfabia@cisco.com>

2 files changed, 49 insertions, 45 deletions

diff --git a/src/plugins/nat/in2out.c b/src/plugins/nat/in2out.c
index f009ce47d78..5d6969f5789 100755
--- a/src/plugins/nat/in2out.c
+++ b/src/plugins/nat/in2out.c
@@ -254,14 +254,13 @@ snat_not_translate (snat_main_t * sm, vlib_node_runtime_t *node,
 
 static inline int
 nat_not_translate_output_feature (snat_main_t * sm, ip4_header_t * ip0,
-                                  u32 proto0, u32 thread_index)
+                                  u32 proto0, u16 src_port, u32 thread_index)
 {
-  udp_header_t * udp0 = ip4_next_header (ip0);
   snat_session_key_t key0;
   clib_bihash_kv_8_8_t kv0, value0;
 
   key0.addr = ip0->src_address;
-  key0.port = udp0->src_port;
+  key0.port = src_port;
   key0.protocol = proto0;
   key0.fib_index = sm->outside_fib_index;
   kv0.key = key0.as_u64;
@@ -562,7 +561,7 @@ u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
       if (vnet_buffer(b0)->sw_if_index[VLIB_TX] != ~0)
         {
           if (PREDICT_FALSE(nat_not_translate_output_feature(sm,
-              ip0, IP_PROTOCOL_ICMP, thread_index)))
+              ip0, SNAT_PROTOCOL_ICMP, key0.port, thread_index)))
             {
               dont_translate = 1;
               goto out;
@@ -571,7 +570,7 @@ u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
       else
         {
           if (PREDICT_FALSE(snat_not_translate(sm, node, sw_if_index0,
-              ip0, IP_PROTOCOL_ICMP, rx_fib_index0, thread_index)))
+              ip0, SNAT_PROTOCOL_ICMP, rx_fib_index0, thread_index)))
             {
               dont_translate = 1;
               goto out;
@@ -1602,7 +1601,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                   if (is_output_feature)
                     {
                       if (PREDICT_FALSE(nat_not_translate_output_feature(sm,
-                          ip0, proto0, thread_index)))
+                          ip0, proto0, udp0->src_port, thread_index)))
                         goto trace00;
                     }
                   else
@@ -1794,7 +1793,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                   if (is_output_feature)
                     {
                       if (PREDICT_FALSE(nat_not_translate_output_feature(sm,
-                          ip1, proto1, thread_index)))
+                          ip1, proto1, udp1->src_port, thread_index)))
                         goto trace00;
                     }
                   else
@@ -2022,7 +2021,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                   if (is_output_feature)
                     {
                       if (PREDICT_FALSE(nat_not_translate_output_feature(sm,
-                          ip0, proto0, thread_index)))
+                          ip0, proto0, udp0->src_port, thread_index)))
                         goto trace0;
                     }
                   else
diff --git a/test/test_nat.py b/test/test_nat.py
index ec2009ef6fd..344a459cbde 100644
--- a/test/test_nat.py
+++ b/test/test_nat.py
@@ -1806,10 +1806,36 @@ class TestNAT44(MethodHolder):
             self.logger.error(ppp("Unexpected or invalid packet:", p))
             raise
 
-        # multiple clients
+    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
+    def test_static_lb_multi_clients(self):
+        """ NAT44 local service load balancing - multiple clients"""
+
+        external_addr_n = socket.inet_pton(socket.AF_INET, self.nat_addr)
+        external_port = 80
+        local_port = 8080
+        server1 = self.pg0.remote_hosts[0]
+        server2 = self.pg0.remote_hosts[1]
+
+        locals = [{'addr': server1.ip4n,
+                   'port': local_port,
+                   'probability': 90},
+                  {'addr': server2.ip4n,
+                   'port': local_port,
+                   'probability': 10}]
+
+        self.nat44_add_address(self.nat_addr)
+        self.vapi.nat44_add_del_lb_static_mapping(external_addr_n,
+                                                  external_port,
+                                                  IP_PROTOS.tcp,
+                                                  local_num=len(locals),
+                                                  locals=locals)
+        self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
+                                                  is_inside=0)
+
         server1_n = 0
         server2_n = 0
-        clients = ip4_range(self.pg1.remote_ip4, 10, 20)
+        clients = ip4_range(self.pg1.remote_ip4, 10, 50)
         pkts = []
         for client in clients:
             p = (Ether(src=self.pg1.remote_mac, dst=self.pg1.local_mac) /
@@ -3327,47 +3353,26 @@ class TestNAT44(MethodHolder):
             raise
 
         # from local network host to external network
-        ext_port = 0
-        p = (Ether(src=self.pg0.remote_mac, dst=self.pg0.local_mac) /
-             IP(src=self.pg0.remote_ip4, dst=self.pg1.remote_ip4) /
-             TCP(sport=23456, dport=34567))
-        self.pg0.add_stream(p)
+        pkts = self.create_stream_in(self.pg0, self.pg1)
+        self.pg0.add_stream(pkts)
         self.pg_enable_capture(self.pg_interfaces)
         self.pg_start()
-        capture = self.pg1.get_capture(1)
-        p = capture[0]
-        try:
-            ip = p[IP]
-            tcp = p[TCP]
-            self.assertEqual(ip.src, self.nat_addr)
-            self.assertNotEqual(tcp.sport, 23456)
-            ext_port = tcp.sport
-            self.check_tcp_checksum(p)
-            self.check_ip_checksum(p)
-        except:
-            self.logger.error(ppp("Unexpected or invalid packet:", p))
-            raise
+        capture = self.pg1.get_capture(len(pkts))
+        self.verify_capture_out(capture)
+        pkts = self.create_stream_in(self.pg0, self.pg1)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        capture = self.pg1.get_capture(len(pkts))
+        self.verify_capture_out(capture)
 
         # from external network back to local network host
-        p = (Ether(src=self.pg1.remote_mac, dst=self.pg1.local_mac) /
-             IP(src=self.pg1.remote_ip4, dst=self.nat_addr) /
-             TCP(sport=34567, dport=ext_port))
-        self.pg1.add_stream(p)
+        pkts = self.create_stream_out(self.pg1)
+        self.pg1.add_stream(pkts)
         self.pg_enable_capture(self.pg_interfaces)
         self.pg_start()
-        capture = self.pg0.get_capture(1)
-        p = capture[0]
-        server = None
-        try:
-            ip = p[IP]
-            tcp = p[TCP]
-            self.assertEqual(ip.dst, self.pg0.remote_ip4)
-            self.assertEqual(tcp.dport, 23456)
-            self.check_tcp_checksum(p)
-            self.check_ip_checksum(p)
-        except:
-            self.logger.error(ppp("Unexpected or invalid packet:", p))
-            raise
+        capture = self.pg0.get_capture(len(pkts))
+        self.verify_capture_in(capture, self.pg0)
 
     def test_output_feature_and_service2(self):
         """ NAT44 interface output feature and service host direct access """