From 98874cda5853ea2d6b2dc32001b935d394b88430 Mon Sep 17 00:00:00 2001 From: =?utf8?q?J=C3=BAlius=20Milan?= Date: Tue, 16 Feb 2021 19:20:47 +0100 Subject: [PATCH] fib: fix sa selection for fib routed destinations MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The move from ip4(6)_src_address_for_packet to fib_sas4(6)_get changed the behavior, so that the new looked only to adjacent gleans. This caused a problem for destinations routed according to FIB table. To reproduce: vpp# create tap vpp# set interface state tap0 up vpp# set interface ip address tap0 192.168.11.1/24 vpp# ip route add 192.168.20.0/24 via 192.168.11.2 linux$ sudo ip addr add 192.168.20.1/24 dev lo linux$ sudo ip link set tap0 up linux$ sudo ip addr add 192.168.11.2/24 dev tap0 vpp# ping 192.168.20.1 Failed: no source address for egress interface Type: fix Signed-off-by: Július Milan Signed-off-by: Neale Ranns Change-Id: I22899f4dbbf8c1c85ccce72f801b92c183195b5d --- src/vnet/adj/adj_glean.c | 18 ++++++++++++++---- test/test_ping.py | 26 +++++++++++++++++++++++++- 2 files changed, 39 insertions(+), 5 deletions(-) diff --git a/src/vnet/adj/adj_glean.c b/src/vnet/adj/adj_glean.c index e956318a1ff..8df104bd19d 100644 --- a/src/vnet/adj/adj_glean.c +++ b/src/vnet/adj/adj_glean.c @@ -258,8 +258,8 @@ adj_glean_get_src (fib_protocol_t proto, u32 sw_if_index, const ip46_address_t *nh) { + const ip46_address_t *conn, *source; const ip_adjacency_t *adj; - ip46_address_t *conn; adj_index_t ai; if (vec_len(adj_gleans[proto]) <= sw_if_index || @@ -274,23 +274,33 @@ adj_glean_get_src (fib_protocol_t proto, if (nh) pfx.fp_addr = *nh; + /* + * An interface can have more than one glean address. Where + * possible we want to return a source address from the same + * subnet as the destination. If this is not possible then any address + * will do. + */ + source = NULL; + hash_foreach_mem(conn, ai, adj_gleans[proto][sw_if_index], ({ adj = adj_get(ai); if (adj->sub_type.glean.rx_pfx.fp_len > 0) { + source = &adj->sub_type.glean.rx_pfx.fp_addr; + /* if no destination is specified use the just glean */ if (NULL == nh) - return (&adj->sub_type.glean.rx_pfx.fp_addr); + return (source); /* check the clean covers the desintation */ if (fib_prefix_is_cover(&adj->sub_type.glean.rx_pfx, &pfx)) - return (&adj->sub_type.glean.rx_pfx.fp_addr); + return (source); } })); - return (NULL); + return (source); } void diff --git a/test/test_ping.py b/test/test_ping.py index 40ad9d4efe0..8c5c087b0c5 100644 --- a/test/test_ping.py +++ b/test/test_ping.py @@ -7,7 +7,7 @@ from scapy.packet import Raw from framework import VppTestCase from util import ppp -from vpp_ip_route import VppIpInterfaceAddress +from vpp_ip_route import VppIpInterfaceAddress, VppIpRoute, VppRoutePath from vpp_neighbor import VppNeighbor """ TestPing is a subclass of VPPTestCase classes. @@ -150,3 +150,27 @@ class TestPing(VppTestCase): for p in out: icmp = self.verify_ping_request(p, "10.0.0.1", nbr_addr, icmp_seq) icmp_seq = icmp_seq + 1 + + def test_ping_fib_routed_dst(self): + """ ping destination routed according to FIB table """ + + try: + self.pg1.generate_remote_hosts(1) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + routed_dst = "10.0.2.0" + self.logger.info(self.vapi.cli("show ip4 neighbors")) + VppIpRoute(self, routed_dst, 24, + [VppRoutePath(self.pg1.remote_hosts[0].ip4, + self.pg1.sw_if_index)]).add_vpp_config() + ping_cmd = "ping %s interval 0.01 repeat 3" % routed_dst + ret = self.vapi.cli(ping_cmd) + self.logger.info(ret) + out = self.pg1.get_capture(3) + icmp_seq = 1 + for p in out: + self.verify_ping_request(p, self.pg1.local_ip4, routed_dst, + icmp_seq) + icmp_seq = icmp_seq + 1 + finally: + self.vapi.cli("show error") -- 2.16.6