Whenever the acl reject rule is hit by a TCP segment send back a TCP RST packet to close the connection using the tcp_reset action. Moreover add add tcp_reset test case to 'ACL reject rule test'
Signed-off-by: Lorenzo Bianconi <[email protected]> --- ovn/northd/ovn-northd.c | 14 +++++++++----- tests/ovn.at | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+), 5 deletions(-) diff --git a/ovn/northd/ovn-northd.c b/ovn/northd/ovn-northd.c index 396381049..b299703f9 100644 --- a/ovn/northd/ovn-northd.c +++ b/ovn/northd/ovn-northd.c @@ -2905,9 +2905,11 @@ build_pre_acls(struct ovn_datapath *od, struct hmap *lflows) * Not to do conntrack on ND and ICMP destination * unreachable packets. */ ovn_lflow_add(lflows, od, S_SWITCH_IN_PRE_ACL, 110, - "nd || nd_rs || nd_ra || icmp4.type == 3", "next;"); + "nd || nd_rs || nd_ra || icmp4.type == 3 || " + "(tcp && tcp.flags == 4)", "next;"); ovn_lflow_add(lflows, od, S_SWITCH_OUT_PRE_ACL, 110, - "nd || nd_rs || nd_ra || icmp4.type == 3", "next;"); + "nd || nd_rs || nd_ra || icmp4.type == 3 || " + "(tcp && tcp.flags == 4)", "next;"); /* Ingress and Egress Pre-ACL Table (Priority 100). * @@ -3097,14 +3099,16 @@ build_reject_acl_rules(struct ovn_datapath *od, struct hmap *lflows, struct ds actions = DS_EMPTY_INITIALIZER; bool ingress = (stage == S_SWITCH_IN_ACL); - /* XXX: Treat TCP connections as "drop;" for now */ build_acl_log(&actions, acl); if (extra_match->length > 0) { ds_put_format(&match, "(%s) && ", extra_match->string); } ds_put_format(&match, "ip && tcp && (%s)", acl->match); - ds_put_cstr(&actions, "/* drop */"); - ovn_lflow_add(lflows, od, stage, acl->priority + OVN_ACL_PRI_OFFSET, + ds_put_format(&actions, "reg0 = 0; " + "eth.dst <-> eth.src; ip4.dst <-> ip4.src; " + "tcp_reset { outport <-> inport; %s };", + ingress ? "output;" : "next(pipeline=ingress,table=0);"); + ovn_lflow_add(lflows, od, stage, acl->priority + OVN_ACL_PRI_OFFSET + 10, ds_cstr(&match), ds_cstr(&actions)); /* IPv4 traffic */ diff --git a/tests/ovn.at b/tests/ovn.at index 4cd3bbf9b..0f37b8892 100644 --- a/tests/ovn.at +++ b/tests/ovn.at @@ -9386,6 +9386,34 @@ 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_DST 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_DST, 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 from ACL rule hit +# +# 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_DST 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 ipv4_dst=$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}${ipv4_src}${ipv4_dst}${tcp_sport}${tcp_dport}000000010000000050027210${tcp_chksum}0000 + + local tcp_rst_ttl=ff + local reply=${eth_src}${eth_dst}08004500002800004000${tcp_rst_ttl}06${exp_ip_chksum}${ipv4_dst}${ipv4_src}${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 +} + # Create hypervisors hv[123]. # Add vif1[123] to hv1, vif2[123] to hv2, vif3[123] to hv3. # Add all of the vifs to a single logical switch sw0. @@ -9432,6 +9460,10 @@ test_ip_packet 11 1 000000000011 000000000021 $(ip_to_hex 192 168 1 11) $(ip_to_ test_ip_packet 21 2 000000000021 000000000011 $(ip_to_hex 192 168 1 21) $(ip_to_hex 192 168 1 11) 0000 7d8d fcfe test_ip_packet 31 3 000000000031 000000000012 $(ip_to_hex 192 168 1 31) $(ip_to_hex 192 168 1 12) 0000 7d82 fcfe +test_tcp_syn_packet 11 1 000000000011 000000000021 $(ip_to_hex 192 168 1 11) $(ip_to_hex 192 168 1 21) 0000 8b40 3039 0000 7d8d 4486 +test_tcp_syn_packet 21 2 000000000021 000000000011 $(ip_to_hex 192 168 1 21) $(ip_to_hex 192 168 1 11) 0000 8b40 3039 0000 7d8d 4486 +test_tcp_syn_packet 31 3 000000000031 000000000012 $(ip_to_hex 192 168 1 31) $(ip_to_hex 192 168 1 12) 0000 8b40 3039 0000 7d82 4486 + for i in 1 2 3; do OVN_CHECK_PACKETS([hv$i/vif${i}1-tx.pcap], [vif${i}1.expected]) done -- 2.14.3 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
