Using icmp4 action, send an ICMP time exceeded frame whenever
an OVN logical router receives an IPv4 packets whose TTL has
expired (ip.ttl == {0, 1})Signed-off-by: Lorenzo Bianconi <[email protected]> --- ovn/northd/ovn-northd.8.xml | 4 --- ovn/northd/ovn-northd.c | 26 +++++++++++++-- tests/ovn.at | 77 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 100 insertions(+), 7 deletions(-) diff --git a/ovn/northd/ovn-northd.8.xml b/ovn/northd/ovn-northd.8.xml index 1d68f1aab..759d3dace 100644 --- a/ovn/northd/ovn-northd.8.xml +++ b/ovn/northd/ovn-northd.8.xml @@ -1401,10 +1401,6 @@ icmp4 { next; }; </pre> - - <p> - Not yet implemented. - </p> </li> <li> diff --git a/ovn/northd/ovn-northd.c b/ovn/northd/ovn-northd.c index 0e06776ad..60f43e2a6 100644 --- a/ovn/northd/ovn-northd.c +++ b/ovn/northd/ovn-northd.c @@ -4852,9 +4852,7 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, ovn_lflow_add(lflows, od, S_ROUTER_IN_IP_INPUT, 50, "eth.bcast", "drop;"); - /* TTL discard. - * - * XXX Need to send ICMP time exceeded if !ip.later_frag. */ + /* TTL discard */ ds_clear(&match); ds_put_cstr(&match, "ip4 && ip.ttl == {0, 1}"); ovn_lflow_add(lflows, od, S_ROUTER_IN_IP_INPUT, 30, @@ -4920,6 +4918,28 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, ds_cstr(&match), ds_cstr(&actions)); } + /* ICMP time exceeded */ + for (int i = 0; i < op->lrp_networks.n_ipv4_addrs; i++) { + ds_clear(&match); + ds_clear(&actions); + + ds_put_format(&match, + "inport == %s && ip4 && " + "ip.ttl == {0, 1} && !ip.later_frag", op->json_key); + ds_put_format(&actions, + "icmp4 {" + "eth.dst <-> eth.src; " + "icmp4.type = 11; /* Time exceeded */ " + "icmp4.code = 0; /* TTL exceeded in transit */ " + "ip4.dst = ip4.src; " + "ip4.src = %s; " + "ip.ttl = 255; " + "next; };", + op->lrp_networks.ipv4_addrs[i].addr_s); + ovn_lflow_add(lflows, op->od, S_ROUTER_IN_IP_INPUT, 40, + ds_cstr(&match), ds_cstr(&actions)); + } + /* ARP reply. These flows reply to ARP requests for the router's own * IP address. */ for (int i = 0; i < op->lrp_networks.n_ipv4_addrs; i++) { diff --git a/tests/ovn.at b/tests/ovn.at index f12c24c17..81c834276 100644 --- a/tests/ovn.at +++ b/tests/ovn.at @@ -10267,3 +10267,80 @@ $PYTHON "$top_srcdir/utilities/ovs-pcap.in" hv1/vif2-tx.pcap > 2.packets AT_CHECK([cat 2.packets], [0], []) AT_CLEANUP + +AT_SETUP([ovn -- TTL exceeded]) +AT_KEYWORDS([ttl-exceeded]) +AT_SKIP_IF([test $HAVE_PYTHON = no]) +ovn_start + +# test_ip_packet INPORT HV ETH_SRC ETH_DST IPV4_SRC IPV4_DST IPV4_ROUTER IP_CHKSUM EXP_IP_CHKSUM EXP_ICMP_CHKSUM +# +# Causes a packet to be received on INPORT of the hypervisor HV. The packet is an IPv4 packet with +# ETH_SRC, ETH_DST, IPV4_SRC, IPV4_DST, IP_CHKSUM as specified and TTL set to 1. +# EXP_IP_CHKSUM and EXP_ICMP_CHKSUM are the ip and icmp checksums of the icmp time exceeded frame +# generated by OVN logical router +# +# INPORT is a lport number, e.g. 11 for vif11. +# HV is a hypervisor number +# ETH_SRC and ETH_DST are each 12 hex digits. +# IPV4_SRC, IPV4_DST and IPV4_ROUTER are each 8 hex digits. +# IP_CHKSUM, EXP_IP_CHSUM and EXP_ICMP_CHKSUM are each 4 hex digits +test_ip_packet() { + local inport=$1 hv=$2 eth_src=$3 eth_dst=$4 ipv4_src=$5 ipv4_dst=$6 ip_router=$7 ip_chksum=$8 + local exp_ip_chksum=$9 exp_icmp_chksum=${10} + shift 10 + + local ip_ttl=01 + local packet=${eth_dst}${eth_src}08004500001400004000${ip_ttl}01${ip_chksum}${ipv4_src}${ipv4_dst} + + local reply_icmp_ttl=fe + local icmp_type_code_response=0b00 + local icmp_data=00000000 + local reply_icmp_payload=${icmp_type_code_response}${exp_icmp_chksum}${icmp_data} + local reply=${eth_src}${eth_dst}08004500001c00004000${reply_icmp_ttl}01${exp_ip_chksum}${ip_router}${ipv4_src}${reply_icmp_payload} + echo $reply >> vif$inport.expected + + as hv$hv ovs-appctl netdev-dummy/receive vif$inport $packet +} + +ip_to_hex() { + printf "%02x%02x%02x%02x" "$@" +} + +for i in 1 2; do + net_add n$i + ovn-nbctl ls-add sw$i + + sim_add hv$i + as hv$i + ovs-vsctl add-br br-phys + ovn_attach n$i br-phys 192.168.$i.1 + + ovn-nbctl lsp-add sw$i sw$i-p${i}0 -- \ + lsp-set-addresses sw$i-p${i}0 "00:00:00:00:00:0$i 192.168.$i.1" + + ovs-vsctl -- add-port br-int vif$i -- \ + set interface vif$i \ + external-ids:iface-id=sw$i-p${i}0 \ + options:tx_pcap=hv$i/vif$i-tx.pcap \ + options:rxq_pcap=hv$i/vif$i-rx.pcap \ + ofport-request=$i +done + +ovn-nbctl lr-add lr0 +for i in 1 2; do + ovn-nbctl lrp-add lr0 lrp$i 00:00:00:00:ff:0$i 192.168.$i.254/24 + ovn-nbctl -- lsp-add sw$i lrp$i-attachment \ + -- set Logical_Switch_Port lrp$i-attachment type=router \ + options:router-port=lrp$i addresses='"00:00:00:00:ff:'0$i'"' +done + +OVN_POPULATE_ARP +# allow some time for ovn-northd and ovn-controller to catch up. +sleep 1 + +test_ip_packet 1 1 000000000001 00000000ff01 $(ip_to_hex 192 168 1 1) $(ip_to_hex 192 168 2 1) $(ip_to_hex 192 168 1 254) 0000 7dae f4ff +OVN_CHECK_PACKETS([hv1/vif1-tx.pcap], [vif1.expected]) + +OVN_CLEANUP([hv1], [hv2]) +AT_CLEANUP -- 2.14.4 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
