Current OVS intercepts and processes all BFD packets, thus VM-2-VM BFD packets get lost and the recipient VM never sees them.
This patch fixes it by only intercepting and processing BFD packets destined to a configured BFD instance, and other BFD packets are made available to the OVS flow table for forwarding. This patch keeps BFD's backward compatibility. VMWare-BZ: 2579326 Signed-off-by: Yifeng Sun <pkusunyif...@gmail.com> --- v1->v2: Add test by William's suggestion. v2->v3: Fix BFD config, thanks William. lib/bfd.c | 16 +++++++++++++--- tests/system-traffic.at | 43 +++++++++++++++++++++++++++++++++++++++++++ vswitchd/vswitch.xml | 7 +++++++ 3 files changed, 63 insertions(+), 3 deletions(-) diff --git a/lib/bfd.c b/lib/bfd.c index cc8c6857afa4..3c965699ace3 100644 --- a/lib/bfd.c +++ b/lib/bfd.c @@ -149,6 +149,9 @@ BUILD_ASSERT_DECL(BFD_PACKET_LEN == sizeof(struct msg)); #define FLAGS_MASK 0x3f #define DEFAULT_MULT 3 +#define BFD_DEFAULT_SRC_IP 0xA9FE0101 /* 169.254.1.1 */ +#define BFD_DEFAULT_DST_IP 0xA9FE0100 /* 169.254.1.0 */ + struct bfd { struct hmap_node node; /* In 'all_bfds'. */ uint32_t disc; /* bfd.LocalDiscr. Key in 'all_bfds' hmap. */ @@ -457,9 +460,9 @@ bfd_configure(struct bfd *bfd, const char *name, const struct smap *cfg, &bfd->rmt_eth_dst); bfd_lookup_ip(smap_get_def(cfg, "bfd_src_ip", ""), - htonl(0xA9FE0101) /* 169.254.1.1 */, &bfd->ip_src); + htonl(BFD_DEFAULT_SRC_IP), &bfd->ip_src); bfd_lookup_ip(smap_get_def(cfg, "bfd_dst_ip", ""), - htonl(0xA9FE0100) /* 169.254.1.0 */, &bfd->ip_dst); + htonl(BFD_DEFAULT_DST_IP), &bfd->ip_dst); forwarding_if_rx = smap_get_bool(cfg, "forwarding_if_rx", false); if (bfd->forwarding_if_rx != forwarding_if_rx) { @@ -674,7 +677,14 @@ bfd_should_process_flow(const struct bfd *bfd_, const struct flow *flow, memset(&wc->masks.nw_proto, 0xff, sizeof wc->masks.nw_proto); if (flow->nw_proto == IPPROTO_UDP && !(flow->nw_frag & FLOW_NW_FRAG_LATER) - && tp_dst_equals(flow, BFD_DEST_PORT, wc)) { + && tp_dst_equals(flow, BFD_DEST_PORT, wc) + && (bfd->ip_src == htonl(BFD_DEFAULT_SRC_IP) + || bfd->ip_src == flow->nw_dst)) { + + if (bfd->ip_src == flow->nw_dst) { + memset(&wc->masks.nw_dst, 0xffffffff, sizeof wc->masks.nw_dst); + } + bool check_tnl_key; atomic_read_relaxed(&bfd->check_tnl_key, &check_tnl_key); diff --git a/tests/system-traffic.at b/tests/system-traffic.at index 2a0fbadff4a1..5c1aee49aba2 100644 --- a/tests/system-traffic.at +++ b/tests/system-traffic.at @@ -6289,3 +6289,46 @@ OVS_WAIT_UNTIL([cat p2.pcap | egrep "0x0050: *0000 *0000 *5002 *2000 *b85e *0000 OVS_TRAFFIC_VSWITCHD_STOP AT_CLEANUP + +AT_SETUP([bfd - BFD overlay]) +OVS_CHECK_GENEVE() + +OVS_TRAFFIC_VSWITCHD_START() + +AT_CHECK([ovs-vsctl -- set bridge br0 other-config:hwaddr=\"f2:ff:00:00:00:01\"]) +ADD_BR([br-underlay], [set bridge br-underlay other-config:hwaddr=\"ee:09:e0:4d:bf:31\"]) + +AT_CHECK([ovs-ofctl add-flow br0 "actions=normal"]) +AT_CHECK([ovs-ofctl add-flow br-underlay "actions=normal"]) + +ADD_NAMESPACES(at_ns0) + +dnl Set up underlay link from host into the namespace using veth pair. +ADD_VETH(p0, at_ns0, br-underlay, "172.16.180.105/24", 4e:12:5d:6c:74:3d) +AT_CHECK([ip addr add dev br-underlay "172.16.180.106/24"]) +AT_CHECK([ip link set dev br-underlay up]) + +dnl Set up tunnel endpoints on OVS outside the namespace. +ADD_OVS_TUNNEL([geneve], [br0], [at_gnv0], [172.16.180.105], [192.168.10.100/24], + [options:packet_type=ptap]) +AT_CHECK([ovs-vsctl -- set Interface at_gnv0 bfd:enable=true bfd:bfd_src_ip=172.16.180.106]) + +dnl Certain Linux distributions, like CentOS, have default iptable rules +dnl to reject input traffic from br-underlay. Here we add a rule to walk +dnl around it. +iptables -I INPUT 1 -i br-underlay -j ACCEPT +on_exit 'iptables -D INPUT 1' + +dnl Firstly, test normal BFD packet. +ovs-ofctl -O OpenFlow13 packet-out br-underlay "in_port=1 packet=ee09e04dbf314e125d6c743d080045c0006624d94000401153f9ac10b469ac10b46a739f17c1005247f900806558000000000023200000016a0f5a9ed376080045c0003400000000ff11fa03ac10b469ac10b46ac0070ec80020000021c003187b3c96ebbc96b962000186a0000f424000000000 actions=NORMAL" +dnl Next we test overlay BFD packet. +ovs-ofctl -O OpenFlow13 packet-out br-underlay "in_port=1 packet=ee09e04dbf314e125d6c743d08004500005b2558400040115445ac10b469ac10b46a6b1017c1004722c1024065580000000001048001001803005254009d0b6d5254000c89840800450000210e22400040119688c0a80a68c0a80a6995cd0ec8000dd342746573740a actions=NORMAL" + +ovs-dpctl dump-flows > datapath-flows.txt +dnl BFD packet was handled by BFD flow. Ipv4.dst is matched. +AT_FAIL_IF([cat datapath-flows.txt | egrep "tunnel\(.*,src=172.16.180.105,dst=172.16.180.106,.*,eth\(\),eth_type\(0x0800\),ipv4\(dst=172.16.180.106,proto=17,.*\),udp\(dst=3784\), .*, actions:userspace\(pid=.*,slow_path\(bfd\)\)" 2>&1 1>/dev/null]) +dnl Overlay BFD packet was handled by non-BFD flows. +AT_FAIL_IF([cat datapath-flows.txt | egrep "tunnel\(.*,src=172.16.180.105,dst=172.16.180.106,.*,eth\(.*\),eth_type\(0x0800\),ipv4\(src=192.168.10.104,dst=192.168.10.105,proto=17,.*\),udp\(.*,dst=3784\), .*, actions:drop" 2>&1 1>/dev/null]) + +OVS_TRAFFIC_VSWITCHD_STOP +AT_CLEANUP diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml index b6acb34ca1b8..e1f895134ff2 100644 --- a/vswitchd/vswitch.xml +++ b/vswitchd/vswitch.xml @@ -3662,6 +3662,13 @@ ovs-vsctl add-port br0 p0 -- set Interface p0 type=patch options:peer=p1 \ optional Authentication or ``Echo Mode'' features. </p> + <p> + OVS 2.13 and earlier intercepted and processed all BFD packets. + OVS 2.14 and later only intercept and process BFD packets destined + to a configured BFD instance, and other BFD packets are made available + to the OVS flow table for forwarding. + </p> + <group title="BFD Configuration"> <p> A controller sets up key-value pairs in the <ref column="bfd"/> -- 2.7.4 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev