diff options
| -rw-r--r-- | src/plugins/snat/in2out.c | 206 | ||||
| -rw-r--r-- | test/test_snat.py | 111 |
2 files changed, 189 insertions, 128 deletions
diff --git a/src/plugins/snat/in2out.c b/src/plugins/snat/in2out.c index ba752cf0d41..fba852c6fe1 100644 --- a/src/plugins/snat/in2out.c +++ b/src/plugins/snat/in2out.c @@ -115,6 +115,93 @@ typedef enum { SNAT_IN2OUT_N_NEXT, } snat_in2out_next_t; +/** + * @brief Check if packet should be translated + * + * Packets aimed at outside interface and external addresss with active session + * should be translated. + * + * @param sm SNAT main + * @param rt SNAT runtime data + * @param sw_if_index0 index of the inside interface + * @param ip0 IPv4 header + * @param proto0 SNAT protocol + * @param rx_fib_index0 RX FIB index + * + * @returns 0 if packet should be translated otherwise 1 + */ +static inline int +snat_not_translate (snat_main_t * sm, snat_runtime_t * rt, u32 sw_if_index0, + ip4_header_t * ip0, u32 proto0, u32 rx_fib_index0) +{ + ip4_address_t * first_int_addr; + udp_header_t * udp0 = ip4_next_header (ip0); + snat_session_key_t key0, sm0; + clib_bihash_kv_8_8_t kv0, value0; + fib_node_index_t fei = FIB_NODE_INDEX_INVALID; + fib_prefix_t pfx = { + .fp_proto = FIB_PROTOCOL_IP4, + .fp_len = 32, + .fp_addr = { + .ip4.as_u32 = ip0->dst_address.as_u32, + }, + }; + + if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) + { + first_int_addr = + ip4_interface_first_address (sm->ip4_main, sw_if_index0, + 0 /* just want the address */); + rt->cached_sw_if_index = sw_if_index0; + if (first_int_addr) + rt->cached_ip4_address = first_int_addr->as_u32; + else + rt->cached_ip4_address = 0; + } + + /* Don't NAT packet aimed at the intfc address */ + if (PREDICT_FALSE(ip0->dst_address.as_u32 == rt->cached_ip4_address)) + return 1; + + key0.addr = ip0->dst_address; + key0.port = udp0->dst_port; + key0.protocol = proto0; + key0.fib_index = sm->outside_fib_index; + kv0.key = key0.as_u64; + + /* NAT packet aimed at external address if */ + /* has active sessions */ + if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0)) + { + /* or is static mappings */ + if (!snat_static_mapping_match(sm, key0, &sm0, 1)) + return 0; + } + else + return 0; + + fei = fib_table_lookup (rx_fib_index0, &pfx); + if (FIB_NODE_INDEX_INVALID != fei) + { + u32 sw_if_index = fib_entry_get_resolving_interface (fei); + if (sw_if_index == ~0) + { + fei = fib_table_lookup (sm->outside_fib_index, &pfx); + if (FIB_NODE_INDEX_INVALID != fei) + sw_if_index = fib_entry_get_resolving_interface (fei); + } + snat_interface_t *i; + pool_foreach (i, sm->interfaces, + ({ + /* NAT packet aimed at outside interface */ + if ((i->is_inside == 0) && (sw_if_index == i->sw_if_index)) + return 0; + })); + } + + return 1; +} + static u32 slow_path (snat_main_t *sm, vlib_buffer_t *b0, ip4_header_t * ip0, u32 rx_fib_index0, @@ -359,25 +446,10 @@ static inline u32 icmp_in2out_slow_path (snat_main_t *sm, if (clib_bihash_search_8_8 (&sm->in2out, &kv0, &value0)) { - ip4_address_t * first_int_addr; - - if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) - { - first_int_addr = - ip4_interface_first_address (sm->ip4_main, sw_if_index0, - 0 /* just want the address */); - rt->cached_sw_if_index = sw_if_index0; - if (first_int_addr) - rt->cached_ip4_address = first_int_addr->as_u32; - else - rt->cached_ip4_address = 0; - } - - /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip0->dst_address.as_u32 == - rt->cached_ip4_address)) + if (PREDICT_FALSE(snat_not_translate(sm, rt, sw_if_index0, ip0, + IP_PROTOCOL_ICMP, rx_fib_index0))) return next0; - + next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0, cpu_index); @@ -652,25 +724,10 @@ snat_in2out_node_fn_inline (vlib_main_t * vm, { if (is_slow_path) { - ip4_address_t * first_int_addr; - - if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) - { - first_int_addr = - ip4_interface_first_address (sm->ip4_main, sw_if_index0, - 0 /* just want the address */); - rt->cached_sw_if_index = sw_if_index0; - if (first_int_addr) - rt->cached_ip4_address = first_int_addr->as_u32; - else - rt->cached_ip4_address = 0; - } - - /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip0->dst_address.as_u32 == - rt->cached_ip4_address)) + if (PREDICT_FALSE(snat_not_translate(sm, rt, sw_if_index0, ip0, + proto0, rx_fib_index0))) goto trace00; - + next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0, cpu_index); if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP)) @@ -803,25 +860,10 @@ snat_in2out_node_fn_inline (vlib_main_t * vm, { if (is_slow_path) { - ip4_address_t * first_int_addr; - - if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index1)) - { - first_int_addr = - ip4_interface_first_address (sm->ip4_main, sw_if_index1, - 0 /* just want the address */); - rt->cached_sw_if_index = sw_if_index1; - if (first_int_addr) - rt->cached_ip4_address = first_int_addr->as_u32; - else - rt->cached_ip4_address = 0; - } - - /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip1->dst_address.as_u32 == - rt->cached_ip4_address)) + if (PREDICT_FALSE(snat_not_translate(sm, rt, sw_if_index1, ip1, + proto1, rx_fib_index1))) goto trace01; - + next1 = slow_path (sm, b1, ip1, rx_fib_index1, &key1, &s1, node, next1, cpu_index); if (PREDICT_FALSE (next1 == SNAT_IN2OUT_NEXT_DROP)) @@ -989,25 +1031,10 @@ snat_in2out_node_fn_inline (vlib_main_t * vm, { if (is_slow_path) { - ip4_address_t * first_int_addr; - - if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) - { - first_int_addr = - ip4_interface_first_address (sm->ip4_main, sw_if_index0, - 0 /* just want the address */); - rt->cached_sw_if_index = sw_if_index0; - if (first_int_addr) - rt->cached_ip4_address = first_int_addr->as_u32; - else - rt->cached_ip4_address = 0; - } - - /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip0->dst_address.as_u32 == - rt->cached_ip4_address)) + if (PREDICT_FALSE(snat_not_translate(sm, rt, sw_if_index0, ip0, + proto0, rx_fib_index0))) goto trace0; - + next0 = slow_path (sm, b0, ip0, rx_fib_index0, &key0, &s0, node, next0, cpu_index); if (PREDICT_FALSE (next0 == SNAT_IN2OUT_NEXT_DROP)) @@ -1375,23 +1402,8 @@ static inline u32 icmp_in2out_static_map (snat_main_t *sm, if (snat_static_mapping_match(sm, key0, &sm0, 0)) { - ip4_address_t * first_int_addr; - - if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) - { - first_int_addr = - ip4_interface_first_address (sm->ip4_main, sw_if_index0, - 0 /* just want the address */); - rt->cached_sw_if_index = sw_if_index0; - if (first_int_addr) - rt->cached_ip4_address = first_int_addr->as_u32; - else - rt->cached_ip4_address = 0; - } - - /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip0->dst_address.as_u32 == - rt->cached_ip4_address)) + if (PREDICT_FALSE(snat_not_translate(sm, rt, sw_if_index0, ip0, + IP_PROTOCOL_ICMP, rx_fib_index0))) return next0; b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION]; @@ -1498,20 +1510,8 @@ snat_in2out_fast_static_map_fn (vlib_main_t * vm, if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP)) { - ip4_address_t * first_int_addr; - - if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) - { - first_int_addr = - ip4_interface_first_address (sm->ip4_main, sw_if_index0, - 0 /* just want the address */); - rt->cached_sw_if_index = sw_if_index0; - rt->cached_ip4_address = first_int_addr->as_u32; - } - - /* Don't NAT packet aimed at the intfc address */ - if (PREDICT_FALSE(ip0->dst_address.as_u32 == - rt->cached_ip4_address)) + if (PREDICT_FALSE(snat_not_translate(sm, rt, sw_if_index0, ip0, + proto0, rx_fib_index0))) goto trace0; next0 = icmp_in2out_static_map diff --git a/test/test_snat.py b/test/test_snat.py index 1abb3daaa40..09fdb108c0b 100644 --- a/test/test_snat.py +++ b/test/test_snat.py @@ -41,11 +41,19 @@ class TestSNAT(VppTestCase): cls.overlapping_interfaces = list(list(cls.pg_interfaces[4:7])) + cls.pg4._local_ip4 = "172.16.255.1" + cls.pg4._local_ip4n = socket.inet_pton(socket.AF_INET, i.local_ip4) + cls.pg4._remote_hosts[0]._ip4 = "172.16.255.2" + cls.pg4.set_table_ip4(10) + cls.pg5._local_ip4 = "172.16.255.3" + cls.pg5._local_ip4n = socket.inet_pton(socket.AF_INET, i.local_ip4) + cls.pg5._remote_hosts[0]._ip4 = "172.16.255.4" + cls.pg5.set_table_ip4(10) + cls.pg6._local_ip4 = "172.16.255.1" + cls.pg6._local_ip4n = socket.inet_pton(socket.AF_INET, i.local_ip4) + cls.pg6._remote_hosts[0]._ip4 = "172.16.255.2" + cls.pg6.set_table_ip4(20) for i in cls.overlapping_interfaces: - i._local_ip4 = "172.16.255.1" - i._local_ip4n = socket.inet_pton(socket.AF_INET, i.local_ip4) - i._remote_hosts[0]._ip4 = "172.16.255.2" - i.set_table_ip4(i.sw_if_index) i.config_ip4() i.admin_up() i.resolve_arp() @@ -178,6 +186,29 @@ class TestSNAT(VppTestCase): "(inside network):", packet)) raise + def verify_capture_no_translation(self, capture, ingress_if, egress_if): + """ + Verify captured packet that don't have to be translated + + :param capture: Captured packets + :param ingress_if: Ingress interface + :param egress_if: Egress interface + """ + for packet in capture: + try: + self.assertEqual(packet[IP].src, ingress_if.remote_ip4) + self.assertEqual(packet[IP].dst, egress_if.remote_ip4) + if packet.haslayer(TCP): + self.assertEqual(packet[TCP].sport, self.tcp_port_in) + elif packet.haslayer(UDP): + self.assertEqual(packet[UDP].sport, self.udp_port_in) + else: + self.assertEqual(packet[ICMP].id, self.icmp_id_in) + except: + self.logger.error(ppp("Unexpected or invalid packet " + "(inside network):", packet)) + raise + def verify_ipfix_nat44_ses(self, data): """ Verify IPFIX NAT44 session create/delete event @@ -462,9 +493,9 @@ class TestSNAT(VppTestCase): self.icmp_id_out = 6305 self.snat_add_static_mapping(self.pg4.remote_ip4, nat_ip1, - vrf_id=self.pg4.sw_if_index) + vrf_id=10) self.snat_add_static_mapping(self.pg0.remote_ip4, nat_ip2, - vrf_id=self.pg4.sw_if_index) + vrf_id=10) self.vapi.snat_interface_add_del_feature(self.pg3.sw_if_index, is_inside=0) self.vapi.snat_interface_add_del_feature(self.pg0.sw_if_index) @@ -494,10 +525,25 @@ class TestSNAT(VppTestCase): 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) - self.vapi.snat_interface_add_del_feature(self.pg2.sw_if_index) self.vapi.snat_interface_add_del_feature(self.pg3.sw_if_index, is_inside=0) + # between two S-NAT inside interfaces (no translation) + 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_no_translation(capture, self.pg0, self.pg1) + + # from S-NAT inside to interface without S-NAT feature (no translation) + pkts = self.create_stream_in(self.pg0, self.pg2) + self.pg0.add_stream(pkts) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + capture = self.pg2.get_capture(len(pkts)) + self.verify_capture_no_translation(capture, self.pg0, self.pg2) + # in2out 1st interface pkts = self.create_stream_in(self.pg0, self.pg3) self.pg0.add_stream(pkts) @@ -530,31 +576,46 @@ class TestSNAT(VppTestCase): capture = self.pg1.get_capture(len(pkts)) self.verify_capture_in(capture, self.pg1) - # in2out 3rd interface - pkts = self.create_stream_in(self.pg2, self.pg3) - self.pg2.add_stream(pkts) - self.pg_enable_capture(self.pg_interfaces) - self.pg_start() - capture = self.pg3.get_capture(len(pkts)) - self.verify_capture_out(capture) - - # out2in 3rd interface - pkts = self.create_stream_out(self.pg3) - self.pg3.add_stream(pkts) - self.pg_enable_capture(self.pg_interfaces) - self.pg_start() - capture = self.pg2.get_capture(len(pkts)) - self.verify_capture_in(capture, self.pg2) - def test_inside_overlapping_interfaces(self): """ SNAT multiple inside interfaces with overlapping address space """ + static_nat_ip = "10.0.0.10" self.snat_add_address(self.snat_addr) self.vapi.snat_interface_add_del_feature(self.pg3.sw_if_index, is_inside=0) self.vapi.snat_interface_add_del_feature(self.pg4.sw_if_index) self.vapi.snat_interface_add_del_feature(self.pg5.sw_if_index) self.vapi.snat_interface_add_del_feature(self.pg6.sw_if_index) + self.snat_add_static_mapping(self.pg6.remote_ip4, static_nat_ip, + vrf_id=20) + + # between S-NAT inside interfaces with same VRF (no translation) + pkts = self.create_stream_in(self.pg4, self.pg5) + self.pg4.add_stream(pkts) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + capture = self.pg5.get_capture(len(pkts)) + self.verify_capture_no_translation(capture, self.pg4, self.pg5) + + # between S-NAT inside interfaces with different VRF (hairpinning) + p = (Ether(src=self.pg4.remote_mac, dst=self.pg4.local_mac) / + IP(src=self.pg4.remote_ip4, dst=static_nat_ip) / + TCP(sport=1234, dport=5678)) + self.pg4.add_stream(p) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + capture = self.pg6.get_capture(1) + p = capture[0] + try: + ip = p[IP] + tcp = p[TCP] + self.assertEqual(ip.src, self.snat_addr) + self.assertEqual(ip.dst, self.pg6.remote_ip4) + self.assertNotEqual(tcp.sport, 1234) + self.assertEqual(tcp.dport, 5678) + except: + self.logger.error(ppp("Unexpected or invalid packet:", p)) + raise # in2out 1st interface pkts = self.create_stream_in(self.pg4, self.pg3) @@ -594,10 +655,10 @@ class TestSNAT(VppTestCase): self.pg_enable_capture(self.pg_interfaces) self.pg_start() capture = self.pg3.get_capture(len(pkts)) - self.verify_capture_out(capture) + self.verify_capture_out(capture, static_nat_ip, True) # out2in 3rd interface - pkts = self.create_stream_out(self.pg3) + pkts = self.create_stream_out(self.pg3, static_nat_ip) self.pg3.add_stream(pkts) self.pg_enable_capture(self.pg_interfaces) self.pg_start() |