SNAT: Remove the oldest translation fix (VPP-568)

Fixed bug and add test.

Change-Id: Ibe70dfc81e6c264223050d316cf6a2a3a0e1524e
Signed-off-by: Matus Fabian <matfabia@cisco.com>

2 files changed, 33 insertions, 0 deletions

diff --git a/test/test_snat.py b/test/test_snat.py
index fdd81f02e75..8985c3e47dc 100644
--- a/test/test_snat.py
+++ b/test/test_snat.py
@@ -589,6 +589,33 @@ class TestSNAT(VppTestCase):
             self.logger.error(ppp("Unexpected or invalid packet:"), p)
             raise
 
+    def test_max_translations_per_user(self):
+        """ MAX translations per user - recycle the least recently used """
+
+        self.snat_add_address(self.snat_addr)
+        self.vapi.snat_interface_add_del_feature(self.pg0.sw_if_index)
+        self.vapi.snat_interface_add_del_feature(self.pg1.sw_if_index,
+                                                 is_inside=0)
+
+        # get maximum number of translations per user
+        snat_config = self.vapi.snat_show_config()
+
+        # send more than maximum number of translations per user packets
+        pkts_num = snat_config.max_translations_per_user + 5
+        pkts = []
+        for port in range(0, pkts_num):
+            p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
+                 IP(src=self.pg0.remote_ip4, dst=self.pg1.remote_ip4) /
+                 TCP(sport=1025 + port))
+            pkts.append(p)
+        self.pg0.add_stream(pkts)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+
+        # verify number of translated packet
+        capture = self.pg1.get_capture()
+        self.assertEqual(pkts_num, len(capture))
+
     def tearDown(self):
         super(TestSNAT, self).tearDown()
         if not self.vpp_dead:
diff --git a/test/vpp_papi_provider.py b/test/vpp_papi_provider.py
index 7c9059295f8..3279a2746d4 100644
--- a/test/vpp_papi_provider.py
+++ b/test/vpp_papi_provider.py
@@ -842,6 +842,12 @@ class VppPapiProvider(object):
         """
         return self.api(self.papi.snat_static_mapping_dump, {})
 
+    def snat_show_config(self):
+        """Show S-NAT config
+        :return: S-NAT config parameters
+        """
+        return self.api(self.papi.snat_show_config, {})
+
     def control_ping(self):
         self.api(self.papi.control_ping)