From f478f758b9fc13089a4ff47fa1e66d7d1db9f003 Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Thu, 17 Feb 2022 15:41:32 +0000 Subject: ping: correct the fib-index used for the reply Type: fix if original packet was to the link local, then the fib index in the buffer is that of the LL table, we can't use that to foward the response if the new destination is global, so reset to the fib index of the link. In other case, the fib index we need has been written to the buffer already. Add a test for IPv6 ping in an MPLS-VPN where int inout interface is not the the same VRF as the response should be sent. Signed-off-by: Neale Ranns Change-Id: I18a232d90ddd3ef051a52476c5d861c87060e76f --- src/plugins/ping/ping.c | 42 +++++++++++++++++++++++++++--------------- test/test_mpls.py | 49 +++++++++++++++++++++++++++++++++++-------------- 2 files changed, 62 insertions(+), 29 deletions(-) diff --git a/src/plugins/ping/ping.c b/src/plugins/ping/ping.c index 2cc6b771268..050048211e6 100644 --- a/src/plugins/ping/ping.c +++ b/src/plugins/ping/ping.c @@ -662,15 +662,20 @@ ip6_icmp_echo_request (vlib_main_t *vm, vlib_node_runtime_t *node, ip0->hop_limit = im->host_config.ttl; ip1->hop_limit = im->host_config.ttl; - /* Determine the correct lookup fib indices... */ - fib_index0 = vec_elt (im->fib_index_by_sw_if_index, - vnet_buffer (p0)->sw_if_index[VLIB_RX]); - vnet_buffer (p0)->sw_if_index[VLIB_TX] = fib_index0; - /* Determine the correct lookup fib indices... */ - fib_index1 = vec_elt (im->fib_index_by_sw_if_index, - vnet_buffer (p1)->sw_if_index[VLIB_RX]); - vnet_buffer (p1)->sw_if_index[VLIB_TX] = fib_index1; - + if (ip6_address_is_link_local_unicast (&ip0->src_address) && + !ip6_address_is_link_local_unicast (&ip0->dst_address)) + { + fib_index0 = vec_elt (im->fib_index_by_sw_if_index, + vnet_buffer (p0)->sw_if_index[VLIB_RX]); + vnet_buffer (p0)->sw_if_index[VLIB_TX] = fib_index0; + } + if (ip6_address_is_link_local_unicast (&ip1->src_address) && + !ip6_address_is_link_local_unicast (&ip1->dst_address)) + { + fib_index1 = vec_elt (im->fib_index_by_sw_if_index, + vnet_buffer (p1)->sw_if_index[VLIB_RX]); + vnet_buffer (p1)->sw_if_index[VLIB_TX] = fib_index1; + } p0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; p1->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; @@ -722,12 +727,19 @@ ip6_icmp_echo_request (vlib_main_t *vm, vlib_node_runtime_t *node, ip0->hop_limit = im->host_config.ttl; - /* if the packet is link local, we'll bounce through the link-local - * table with the RX interface correctly set */ - fib_index0 = vec_elt (im->fib_index_by_sw_if_index, - vnet_buffer (p0)->sw_if_index[VLIB_RX]); - vnet_buffer (p0)->sw_if_index[VLIB_TX] = fib_index0; - + if (ip6_address_is_link_local_unicast (&ip0->src_address) && + !ip6_address_is_link_local_unicast (&ip0->dst_address)) + { + /* if original packet was to the link local, then the + * fib index is that of the LL table, we can't use that + * to foward the response if the new destination + * is global, so reset to the fib index of the link. + * In other case, the fib index we need has been written + * to the buffer already. */ + fib_index0 = vec_elt (im->fib_index_by_sw_if_index, + vnet_buffer (p0)->sw_if_index[VLIB_RX]); + vnet_buffer (p0)->sw_if_index[VLIB_TX] = fib_index0; + } p0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; /* Verify speculative enqueue, maybe switch current next frame */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, diff --git a/test/test_mpls.py b/test/test_mpls.py index f7709d10cc1..4cc7a0759f2 100644 --- a/test/test_mpls.py +++ b/test/test_mpls.py @@ -18,7 +18,7 @@ import scapy.compat from scapy.packet import Raw from scapy.layers.l2 import Ether, ARP from scapy.layers.inet import IP, UDP, ICMP -from scapy.layers.inet6 import IPv6, ICMPv6TimeExceeded +from scapy.layers.inet6 import IPv6, ICMPv6TimeExceeded, ICMPv6EchoRequest from scapy.contrib.mpls import MPLS NUM_PKTS = 67 @@ -196,7 +196,8 @@ class TestMPLS(VppTestCase): return pkts def create_stream_labelled_ip6(self, src_if, mpls_labels, - hlim=64, dst_ip=None): + hlim=64, dst_ip=None, + ping=0, ip_itf=None): if dst_ip is None: dst_ip = src_if.remote_ip6 self.reset_packet_infos() @@ -208,9 +209,14 @@ class TestMPLS(VppTestCase): for l in mpls_labels: p = p / MPLS(label=l.value, ttl=l.ttl, cos=l.exp) - p = p / (IPv6(src=src_if.remote_ip6, dst=dst_ip, hlim=hlim) / - UDP(sport=1234, dport=1234) / - Raw(payload)) + if ping: + p = p / (IPv6(src=ip_itf.remote_ip6, + dst=ip_itf.local_ip6) / + ICMPv6EchoRequest()) + else: + p = p / (IPv6(src=src_if.remote_ip6, dst=dst_ip, hlim=hlim) / + UDP(sport=1234, dport=1234) / + Raw(payload)) info.data = p.copy() pkts.append(p) return pkts @@ -337,7 +343,8 @@ class TestMPLS(VppTestCase): raise def verify_capture_ip6(self, src_if, capture, sent, - ip_hlim=None, ip_dscp=0): + ip_hlim=None, ip_dscp=0, + ping_resp=0): try: self.assertEqual(len(capture), len(sent)) @@ -352,15 +359,18 @@ class TestMPLS(VppTestCase): tx_ip = tx[IPv6] rx_ip = rx[IPv6] - self.assertEqual(rx_ip.src, tx_ip.src) - self.assertEqual(rx_ip.dst, tx_ip.dst) - self.assertEqual(rx_ip.tc, ip_dscp) - # IP processing post pop has decremented the TTL - if not ip_hlim: - self.assertEqual(rx_ip.hlim + 1, tx_ip.hlim) + if not ping_resp: + self.assertEqual(rx_ip.src, tx_ip.src) + self.assertEqual(rx_ip.dst, tx_ip.dst) + self.assertEqual(rx_ip.tc, ip_dscp) + # IP processing post pop has decremented the TTL + if not ip_hlim: + self.assertEqual(rx_ip.hlim + 1, tx_ip.hlim) + else: + self.assertEqual(rx_ip.hlim, ip_hlim) else: - self.assertEqual(rx_ip.hlim, ip_hlim) - + self.assertEqual(rx_ip.src, tx_ip.dst) + self.assertEqual(rx_ip.dst, tx_ip.src) except: raise @@ -1170,6 +1180,13 @@ class TestMPLS(VppTestCase): 0xffffffff, nh_table_id=1)]) route_35_eos.add_vpp_config() + route_356_eos = VppMplsRoute( + self, 356, 1, + [VppRoutePath("0::0", + 0xffffffff, + nh_table_id=1)], + eos_proto=FibPathProto.FIB_PATH_NH_PROTO_IP6) + route_356_eos.add_vpp_config() # # ping an interface in the non-default table @@ -1180,6 +1197,10 @@ class TestMPLS(VppTestCase): self.pg0, [VppMplsLabel(35)], ping=1, ip_itf=self.pg1) rx = self.send_and_expect(self.pg0, tx, self.pg1) self.verify_capture_ip4(self.pg1, rx, tx, ping_resp=1) + tx = self.create_stream_labelled_ip6( + self.pg0, [VppMplsLabel(356)], ping=1, ip_itf=self.pg1) + rx = self.send_and_expect(self.pg0, tx, self.pg1) + self.verify_capture_ip6(self.pg1, rx, tx, ping_resp=1) # # Double pop -- cgit 1.2.3-korg