diff options
| author |   Matus Fabian <matfabia@cisco.com> | 2017-06-09 02:33:30 -0700 |
|---|---|---|
| committer |   Ole Trøan <otroan@employees.org> | 2017-06-13 08:19:10 +0000 |
| commit | 4b30ceb1b4f9174d528525059d7fd52d585f059d (patch) | |
| tree | 1bc96c94b566acf5d9d60054c49f7cc03b6b4ce1 | |
| parent | 3b20ee4e2b66c287d7a67aff1a304b45be55a4a8 (diff) | |
SNAT: fix 1:1 NAT without port hairpinning TCP checksum update
Change-Id: I5077fcf3671a6116b475f87e43120efc10ecaa08
Signed-off-by: Matus Fabian <matfabia@cisco.com>
| -rw-r--r-- | src/plugins/snat/in2out.c | 10 | ||||
| -rw-r--r-- | test/test_snat.py | 17 |
2 files changed, 27 insertions, 0 deletions
diff --git a/src/plugins/snat/in2out.c b/src/plugins/snat/in2out.c index ddde702a..685cdca8 100644 --- a/src/plugins/snat/in2out.c +++ b/src/plugins/snat/in2out.c @@ -854,6 +854,16 @@ snat_hairpinning (snat_main_t *sm, udp0->checksum = 0; } } + else + { + if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP)) + { + sum0 = tcp0->checksum; + sum0 = ip_csum_update (sum0, old_dst_addr0, new_dst_addr0, + ip4_header_t, dst_address); + tcp0->checksum = ip_csum_fold(sum0); + } + } } } diff --git a/test/test_snat.py b/test/test_snat.py index c6344a9e..c2f9280d 100644 --- a/test/test_snat.py +++ b/test/test_snat.py @@ -27,6 +27,17 @@ class MethodHolder(VppTestCase): def tearDown(self): super(MethodHolder, self).tearDown() + def check_tcp_checksum(self, pkt): + """ + Check TCP checksum in IP packet + + :param pkt: Packet to check TCP checksum + """ + new = pkt.__class__(str(pkt)) + del new['TCP'].chksum + new = new.__class__(str(new)) + self.assertEqual(new['TCP'].chksum, pkt['TCP'].chksum) + def create_stream_in(self, in_if, out_if, ttl=64): """ Create packet stream for inside network @@ -1111,6 +1122,7 @@ class TestSNAT(MethodHolder): self.assertEqual(ip.dst, server.ip4) self.assertNotEqual(tcp.sport, host_in_port) self.assertEqual(tcp.dport, server_in_port) + self.check_tcp_checksum(p) host_out_port = tcp.sport except: self.logger.error(ppp("Unexpected or invalid packet:", p)) @@ -1132,6 +1144,7 @@ class TestSNAT(MethodHolder): self.assertEqual(ip.dst, host.ip4) self.assertEqual(tcp.sport, server_out_port) self.assertEqual(tcp.dport, host_in_port) + self.check_tcp_checksum(p) except: self.logger.error(ppp("Unexpected or invalid packet:"), p) raise @@ -1182,6 +1195,7 @@ class TestSNAT(MethodHolder): self.assertNotEqual(packet[TCP].sport, self.tcp_port_in) self.assertEqual(packet[TCP].dport, server_tcp_port) self.tcp_port_out = packet[TCP].sport + self.check_tcp_checksum(packet) elif packet.haslayer(UDP): self.assertNotEqual(packet[UDP].sport, self.udp_port_in) self.assertEqual(packet[UDP].dport, server_udp_port) @@ -1218,6 +1232,7 @@ class TestSNAT(MethodHolder): if packet.haslayer(TCP): self.assertEqual(packet[TCP].dport, self.tcp_port_in) self.assertEqual(packet[TCP].sport, server_tcp_port) + self.check_tcp_checksum(packet) elif packet.haslayer(UDP): self.assertEqual(packet[UDP].dport, self.udp_port_in) self.assertEqual(packet[UDP].sport, server_udp_port) @@ -1253,6 +1268,7 @@ class TestSNAT(MethodHolder): self.assertEqual(packet[TCP].sport, self.tcp_port_in) self.assertEqual(packet[TCP].dport, server_tcp_port) self.tcp_port_out = packet[TCP].sport + self.check_tcp_checksum(packet) elif packet.haslayer(UDP): self.assertEqual(packet[UDP].sport, self.udp_port_in) self.assertEqual(packet[UDP].dport, server_udp_port) @@ -1289,6 +1305,7 @@ class TestSNAT(MethodHolder): if packet.haslayer(TCP): self.assertEqual(packet[TCP].dport, self.tcp_port_in) self.assertEqual(packet[TCP].sport, server_tcp_port) + self.check_tcp_checksum(packet) elif packet.haslayer(UDP): self.assertEqual(packet[UDP].dport, self.udp_port_in) self.assertEqual(packet[UDP].sport, server_udp_port) |