diff options
| author |   Jon Loeliger <jdl@netgate.com> | 2019-11-14 16:44:40 -0600 |
|---|---|---|
| committer |   Ole Trøan <otroan@employees.org> | 2019-11-19 03:41:46 +0000 |
| commit | b15ad95124ca97dd9a800394b93f1fe19567d2e1 (patch) | |
| tree | fa59c275143f0efbf531cb6240e979cefff0e436 /src/plugins/map | |
| parent | 93e060aee441e98adf44a72149679a838d7084f3 (diff) | |
map: Fix TCP MSS clamping for MAP-E traffic.
Original MSS clamp patch by Vladimir Ratnikov.
Modified to apply only to TCP packets.
Type: fix
Test: Wrote new unit test to ensure MAP-E TCP MSS clamping.
Change-Id: I77c69714a2e3cc3b7473aa12b645243bb595c2a2
Signed-off-by: Vladimir Ratnikov <vratnikov@netgate.com>
Signed-off-by: Jon Loeliger <jdl@netgate.com>
Diffstat (limited to 'src/plugins/map')
| -rw-r--r-- | src/plugins/map/ip4_map.c | 14 | ||||
| -rw-r--r-- | src/plugins/map/test/test_map.py | 72 |
2 files changed, 84 insertions, 2 deletions
diff --git a/src/plugins/map/ip4_map.c b/src/plugins/map/ip4_map.c index f2a00907a57..68c3d73094c 100644 --- a/src/plugins/map/ip4_map.c +++ b/src/plugins/map/ip4_map.c @@ -209,6 +209,20 @@ ip4_map (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) */ port0 = ip4_map_port_and_security_check (d0, p0, &error0); + /* + * Clamp TCP MSS value. + */ + if (ip40->protocol == IP_PROTOCOL_TCP) + { + tcp_header_t *tcp = ip4_next_header (ip40); + if (mm->tcp_mss > 0 && tcp_syn (tcp)) + { + ip_csum_t csum = tcp->checksum; + map_mss_clamping (tcp, &csum, mm->tcp_mss); + tcp->checksum = ip_csum_fold (csum); + } + } + /* Decrement IPv4 TTL */ ip4_map_decrement_ttl (ip40, &error0); bool df0 = diff --git a/src/plugins/map/test/test_map.py b/src/plugins/map/test/test_map.py index 0bb7a859f8b..94cb6d7865d 100644 --- a/src/plugins/map/test/test_map.py +++ b/src/plugins/map/test/test_map.py @@ -96,8 +96,8 @@ class TestMAP(VppTestCase): self.assertEqual(rv[0].tag, tag, "output produced incorrect tag value.") - def test_map_e(self): - """ MAP-E """ + def test_map_e_udp(self): + """ MAP-E UDP""" # # Add a route to the MAP-BR @@ -363,6 +363,74 @@ class TestMAP(VppTestCase): self.validate(rx[0][1], v6_reply1) self.validate(rx[1][1], v6_reply2) + def test_map_e_tcp_mss(self): + """ MAP-E TCP MSS""" + + # + # Add a route to the MAP-BR + # + map_br_pfx = "2001::" + map_br_pfx_len = 32 + map_route = VppIpRoute(self, + map_br_pfx, + map_br_pfx_len, + [VppRoutePath(self.pg1.remote_ip6, + self.pg1.sw_if_index)]) + map_route.add_vpp_config() + + # + # Add a domain that maps from pg0 to pg1 + # + map_dst = '2001::/32' + map_src = '3000::1/128' + client_pfx = '192.168.0.0/16' + map_translated_addr = '2001:0:101:5000:0:c0a8:101:5' + tag = 'MAP-E TCP tag.' + self.vapi.map_add_domain(ip4_prefix=client_pfx, + ip6_prefix=map_dst, + ip6_src=map_src, + ea_bits_len=20, + psid_offset=4, + psid_length=4, + tag=tag) + + # Enable MAP on pg0 interface. + self.vapi.map_if_enable_disable(is_enable=1, + sw_if_index=self.pg0.sw_if_index, + is_translation=0) + + # Enable MAP on pg1 interface. + self.vapi.map_if_enable_disable(is_enable=1, + sw_if_index=self.pg1.sw_if_index, + is_translation=0) + + # TCP MSS clamping + mss_clamp = 1300 + self.vapi.map_param_set_tcp(mss_clamp) + + # + # Send a v4 packet that will be encapped. + # + p_ether = Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) + p_ip4 = IP(src=self.pg0.remote_ip4, dst='192.168.1.1') + p_tcp = TCP(sport=20000, dport=30000, flags="S", + options=[("MSS", 1455)]) + p4 = p_ether / p_ip4 / p_tcp + + self.pg1.add_stream(p4) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + + rx = self.pg1.get_capture(1) + rx = rx[0] + + self.assertTrue(rx.haslayer(IPv6)) + self.assertEqual(rx[IP].src, p4[IP].src) + self.assertEqual(rx[IP].dst, p4[IP].dst) + self.assertEqual(rx[IPv6].src, "3000::1") + self.assertEqual(rx[TCP].options, + TCP(options=[('MSS', mss_clamp)]).options) + def validate(self, rx, expected): self.assertEqual(rx, expected.__class__(scapy.compat.raw(expected))) |