Add priority-80 flows to generate TCP reset messages in reply to TCP datagrams directed to the router's IP address since the logical router doesn't accept any TCP traffic
Signed-off-by: Lorenzo Bianconi <lorenzo.bianc...@redhat.com> --- ovn/northd/ovn-northd.8.xml | 4 ---- ovn/northd/ovn-northd.c | 29 ++++++++++++++++++++++++++++- tests/ovn.at | 31 +++++++++++++++++++++++++++++++ 3 files changed, 59 insertions(+), 5 deletions(-) diff --git a/ovn/northd/ovn-northd.8.xml b/ovn/northd/ovn-northd.8.xml index a33de3d95..18a481b3d 100644 --- a/ovn/northd/ovn-northd.8.xml +++ b/ovn/northd/ovn-northd.8.xml @@ -1330,10 +1330,6 @@ nd_na { <p> These flows should not match IP fragments with nonzero offset. </p> - - <p> - Details TBD. Not yet implemented. - </p> </li> <li> diff --git a/ovn/northd/ovn-northd.c b/ovn/northd/ovn-northd.c index 568d19b7d..27d7aab06 100644 --- a/ovn/northd/ovn-northd.c +++ b/ovn/northd/ovn-northd.c @@ -5147,7 +5147,7 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, ds_cstr(&match), ds_cstr(&actions)); } - /* UDP port unreachable */ + /* UDP/TCP port unreachable */ for (int i = 0; i < op->lrp_networks.n_ipv4_addrs; i++) { const char *action; @@ -5164,6 +5164,17 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, "next; };"; ovn_lflow_add(lflows, op->od, S_ROUTER_IN_IP_INPUT, 80, ds_cstr(&match), action); + + ds_clear(&match); + ds_put_format(&match, + "ip4 && ip4.dst == %s && !ip.later_frag && tcp", + op->lrp_networks.ipv4_addrs[i].addr_s); + action = "tcp_reset {" + "eth.dst <-> eth.src; " + "ip4.dst <-> ip4.src; " + "next; };"; + ovn_lflow_add(lflows, op->od, S_ROUTER_IN_IP_INPUT, 80, + ds_cstr(&match), action); } ds_clear(&match); @@ -5285,6 +5296,22 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, ovn_lflow_add(lflows, op->od, S_ROUTER_IN_IP_INPUT, 90, ds_cstr(&match), ds_cstr(&actions)); } + + /* TCP port unreachable */ + for (int i = 0; i < op->lrp_networks.n_ipv6_addrs; i++) { + const char *action; + + ds_clear(&match); + ds_put_format(&match, + "ip6 && ip6.dst == %s && !ip.later_frag && tcp", + op->lrp_networks.ipv6_addrs[i].addr_s); + action = "tcp_reset {" + "eth.dst <-> eth.src; " + "ip6.dst <-> ip6.src; " + "next; };"; + ovn_lflow_add(lflows, op->od, S_ROUTER_IN_IP_INPUT, 80, + ds_cstr(&match), action); + } } /* NAT, Defrag and load balancing. */ diff --git a/tests/ovn.at b/tests/ovn.at index ee807f9c3..4648a303c 100644 --- a/tests/ovn.at +++ b/tests/ovn.at @@ -10379,6 +10379,34 @@ test_ip_packet() { as hv$hv ovs-appctl netdev-dummy/receive vif$inport $packet } +# test_tcp_syn_packet INPORT HV ETH_SRC ETH_DST IPV4_SRC IPV4_ROUTER IP_CHKSUM TCP_SPORT TCP_DPORT TCP_CHKSUM EXP_IP_CHKSUM EXP_TCP_RST_CHKSUM +# +# Causes a packet to be received on INPORT of the hypervisor HV. The packet is an TCP syn segment with +# ETH_SRC, ETH_DST, IPV4_SRC, IPV4_ROUTER, IP_CHKSUM, TCP_SPORT, TCP_DPORT, TCP_CHKSUM as specified. +# EXP_IP_CHKSUM and EXP_TCP_RST_CHKSUM are the ip and tcp checksums of the tcp reset segment generated by OVN logical router +# +# INPORT is an lport number, e.g. 11 for vif11. +# HV is an hypervisor number +# ETH_SRC and ETH_DST are each 12 hex digits. +# IPV4_SRC and IPV4_ROUTER are each 8 hex digits. +# TCP_SPORT and TCP_DPORT are 4 hex digits. +# IP_CHKSUM, TCP_CHKSUM, EXP_IP_CHSUM and EXP_TCP_RST_CHKSUM are each 4 hex digits +test_tcp_syn_packet() { + local inport=$1 hv=$2 eth_src=$3 eth_dst=$4 ipv4_src=$5 ip_router=$6 ip_chksum=$7 + local tcp_sport=$8 tcp_dport=$9 tcp_chksum=${10} + local exp_ip_chksum=${11} exp_tcp_rst_chksum=${12} + shift 12 + + local ip_ttl=ff + local packet=${eth_dst}${eth_src}08004500002800004000${ip_ttl}06${ip_chksum}${ipv4_src}${ip_router}${tcp_sport}${tcp_dport}000000010000000050027210${tcp_chksum}0000 + + local tcp_rst_ttl=fe + local reply=${eth_src}${eth_dst}08004500002800004000${tcp_rst_ttl}06${exp_ip_chksum}${ip_router}${ipv4_src}${tcp_dport}${tcp_sport}000000000000000150040000${exp_tcp_rst_chksum}0000 + echo $reply >> vif$inport.expected + + as hv$hv ovs-appctl netdev-dummy/receive vif$inport $packet +} + ip_to_hex() { printf "%02x%02x%02x%02x" "$@" } @@ -10418,5 +10446,8 @@ ovn-nbctl --wait=hv sync test_ip_packet 1 1 000000000001 00000000ff01 $(ip_to_hex 192 168 1 1) $(ip_to_hex 192 168 1 254) 11 0000 7dae fcfc 0303 OVN_CHECK_PACKETS([hv1/vif1-tx.pcap], [vif1.expected]) +test_tcp_syn_packet 2 2 000000000002 00000000ff02 $(ip_to_hex 192 168 2 1) $(ip_to_hex 192 168 2 254) 0000 8b40 3039 0000 7bae 4486 +OVN_CHECK_PACKETS([hv2/vif2-tx.pcap], [vif2.expected]) + OVN_CLEANUP([hv1], [hv2]) AT_CLEANUP -- 2.17.1 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev