From d95c39e87bf9d21b2a9d4c49fdf7ebca2a5eab3d Mon Sep 17 00:00:00 2001 From: Matus Fabian Date: Tue, 23 Jan 2018 06:07:01 -0800 Subject: [PATCH] NAT44: asymmetrical static mapping and one-armed NAT (VPP-1138) One-armed NAT should work for asymmetrical static mappings without adding external address to the NAT44 pool. Change-Id: Ie886b75b55c3b552d1029a50bd967625fde80f09 Signed-off-by: Matus Fabian --- src/plugins/nat/nat.c | 11 ++++++++- test/test_nat.py | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 74 insertions(+), 1 deletion(-) diff --git a/src/plugins/nat/nat.c b/src/plugins/nat/nat.c index bedf4e5d386..56904ef7e04 100644 --- a/src/plugins/nat/nat.c +++ b/src/plugins/nat/nat.c @@ -387,7 +387,7 @@ nat44_classify_node_fn_inline (vlib_main_t * vm, if (ip0->dst_address.as_u32 == ap->addr.as_u32) { next0 = NAT44_CLASSIFY_NEXT_OUT2IN; - break; + goto enqueue0; } } @@ -401,8 +401,17 @@ nat44_classify_node_fn_inline (vlib_main_t * vm, if (!clib_bihash_search_8_8 (&sm->static_mapping_by_external, &kv0, &value0)) { next0 = NAT44_CLASSIFY_NEXT_OUT2IN; + goto enqueue0; } + udp_header_t * udp0 = ip4_next_header (ip0); + m_key0.port = clib_net_to_host_u16 (udp0->dst_port); + m_key0.protocol = ip_proto_to_snat_proto (ip0->protocol); + kv0.key = m_key0.as_u64; + if (!clib_bihash_search_8_8 (&sm->static_mapping_by_external, &kv0, &value0)) + next0 = NAT44_CLASSIFY_NEXT_OUT2IN; } + + enqueue0: /* verify speculative enqueue, maybe switch current next frame */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, diff --git a/test/test_nat.py b/test/test_nat.py index d2bc4569af0..298863833fa 100644 --- a/test/test_nat.py +++ b/test/test_nat.py @@ -3240,6 +3240,70 @@ class TestNAT44(MethodHolder): self.logger.error(ppp("Unexpected or invalid packet:", p)) raise + def test_one_armed_nat44_static(self): + """ One armed NAT44 and 1:1 NAPT symmetrical rule """ + remote_host = self.pg9.remote_hosts[0] + local_host = self.pg9.remote_hosts[1] + external_port = 80 + local_port = 8080 + eh_port_in = 0 + + self.vapi.nat44_forwarding_enable_disable(1) + self.nat44_add_address(self.nat_addr, twice_nat=1) + self.nat44_add_static_mapping(local_host.ip4, self.nat_addr, + local_port, external_port, + proto=IP_PROTOS.tcp, out2in_only=1, + twice_nat=1) + self.vapi.nat44_interface_add_del_feature(self.pg9.sw_if_index) + self.vapi.nat44_interface_add_del_feature(self.pg9.sw_if_index, + is_inside=0) + + # from client to service + p = (Ether(src=self.pg9.remote_mac, dst=self.pg9.local_mac) / + IP(src=remote_host.ip4, dst=self.nat_addr) / + TCP(sport=12345, dport=external_port)) + self.pg9.add_stream(p) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + capture = self.pg9.get_capture(1) + p = capture[0] + server = None + try: + ip = p[IP] + tcp = p[TCP] + self.assertEqual(ip.dst, local_host.ip4) + self.assertEqual(ip.src, self.nat_addr) + self.assertEqual(tcp.dport, local_port) + self.assertNotEqual(tcp.sport, 12345) + eh_port_in = tcp.sport + self.check_tcp_checksum(p) + self.check_ip_checksum(p) + except: + self.logger.error(ppp("Unexpected or invalid packet:", p)) + raise + + # from service back to client + p = (Ether(src=self.pg9.remote_mac, dst=self.pg9.local_mac) / + IP(src=local_host.ip4, dst=self.nat_addr) / + TCP(sport=local_port, dport=eh_port_in)) + self.pg9.add_stream(p) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + capture = self.pg9.get_capture(1) + p = capture[0] + try: + ip = p[IP] + tcp = p[TCP] + self.assertEqual(ip.src, self.nat_addr) + self.assertEqual(ip.dst, remote_host.ip4) + self.assertEqual(tcp.sport, external_port) + self.assertEqual(tcp.dport, 12345) + self.check_tcp_checksum(p) + self.check_ip_checksum(p) + except: + self.logger.error(ppp("Unexpected or invalid packet:", p)) + raise + def test_del_session(self): """ Delete NAT44 session """ self.nat44_add_address(self.nat_addr) -- 2.16.6