Inotroduce lb_skip_snat in load balancer option column in order to not force_snat traffic that is hitting a given load balancer applied on a logical router where lb_force_snat has been configured
https://bugzilla.redhat.com/show_bug.cgi?id=1927540 Tested-by: Andrew Stoycos <[email protected]> Signed-off-by: Lorenzo Bianconi <[email protected]> --- include/ovn/logical-fields.h | 5 ++++ lib/logical-fields.c | 4 ++++ northd/lrouter.dl | 10 ++++++-- northd/ovn-northd.8.xml | 25 +++++++++++++++++++- northd/ovn-northd.c | 44 ++++++++++++++++++++++++------------ northd/ovn_northd.dl | 32 +++++++++++++++++++------- tests/ovn-northd.at | 25 +++++++++++++++++++- 7 files changed, 119 insertions(+), 26 deletions(-) diff --git a/include/ovn/logical-fields.h b/include/ovn/logical-fields.h index 017176f98..d44b30b30 100644 --- a/include/ovn/logical-fields.h +++ b/include/ovn/logical-fields.h @@ -66,6 +66,7 @@ enum mff_log_flags_bits { MLF_LOOKUP_MAC_BIT = 6, MLF_LOOKUP_LB_HAIRPIN_BIT = 7, MLF_LOOKUP_FDB_BIT = 8, + MLF_SKIP_SNAT_FOR_LB_BIT = 9, }; /* MFF_LOG_FLAGS_REG flag assignments */ @@ -102,6 +103,10 @@ enum mff_log_flags { /* Indicate that the lookup in the fdb table was successful. */ MLF_LOOKUP_FDB = (1 << MLF_LOOKUP_FDB_BIT), + + /* Indicate that a packet must not SNAT in the gateway router when + * load-balancing has taken place. */ + MLF_SKIP_SNAT_FOR_LB = (1 << MLF_SKIP_SNAT_FOR_LB_BIT), }; /* OVN logical fields diff --git a/lib/logical-fields.c b/lib/logical-fields.c index 9d08b44c2..72853013e 100644 --- a/lib/logical-fields.c +++ b/lib/logical-fields.c @@ -121,6 +121,10 @@ ovn_init_symtab(struct shash *symtab) MLF_FORCE_SNAT_FOR_LB_BIT); expr_symtab_add_subfield(symtab, "flags.force_snat_for_lb", NULL, flags_str); + snprintf(flags_str, sizeof flags_str, "flags[%d]", + MLF_SKIP_SNAT_FOR_LB_BIT); + expr_symtab_add_subfield(symtab, "flags.skip_snat_for_lb", NULL, + flags_str); /* Connection tracking state. */ expr_symtab_add_field_scoped(symtab, "ct_mark", MFF_CT_MARK, NULL, false, diff --git a/northd/lrouter.dl b/northd/lrouter.dl index 36cedd2dc..5eb06c77f 100644 --- a/northd/lrouter.dl +++ b/northd/lrouter.dl @@ -355,8 +355,14 @@ function lb_force_snat_router_ip(lr_options: Map<string, string>): bool { lr_options.contains_key("chassis") } -function force_snat_for_lb(lr: nb::Logical_Router): bool { - not get_force_snat_ip(lr, "lb").is_empty() or lb_force_snat_router_ip(lr.options) +function snat_for_lb(lr: nb::Logical_Router, lb: Ref<nb::Load_Balancer>): bit<8> { + if (lb.options.get_bool_def("lb_skip_snat", false)) { + return 2 + }; + if (not get_force_snat_ip(lr, "lb").is_empty() or lb_force_snat_router_ip(lr.options)) { + return 1 + }; + return 0 } /* For each router, collect the set of IPv4 and IPv6 addresses used for SNAT, diff --git a/northd/ovn-northd.8.xml b/northd/ovn-northd.8.xml index a62f5c057..96ab11892 100644 --- a/northd/ovn-northd.8.xml +++ b/northd/ovn-northd.8.xml @@ -2754,7 +2754,11 @@ icmp6 { (and optional port numbers) to load balance to. If the router is configured to force SNAT any load-balanced packets, the above action will be replaced by <code>flags.force_snat_for_lb = 1; - ct_lb(<var>args</var>);</code>. If health check is enabled, then + ct_lb(<var>args</var>);</code>. + If the load balancig rule is configured with <code>lb_skip_snat</code> + set to true, the above action will be replaced by + <code>flags.skip_snat_for_lb = 1; ct_lb(<var>args</var>);</code>. + If health check is enabled, then <var>args</var> will only contain those endpoints whose service monitor status entry in <code>OVN_Southbound</code> db is either <code>online</code> or empty. @@ -2771,6 +2775,9 @@ icmp6 { with an action of <code>ct_dnat;</code>. If the router is configured to force SNAT any load-balanced packets, the above action will be replaced by <code>flags.force_snat_for_lb = 1; ct_dnat;</code>. + If the load balancig rule is configured with <code>lb_skip_snat</code> + set to true, the above action will be replaced by + <code>flags.skip_snat_for_lb = 1; ct_dnat;</code>. </li> <li> @@ -2785,6 +2792,9 @@ icmp6 { to force SNAT any load-balanced packets, the above action will be replaced by <code>flags.force_snat_for_lb = 1; ct_lb(<var>args</var>);</code>. + If the load balancig rule is configured with <code>lb_skip_snat</code> + set to true, the above action will be replaced by + <code>flags.skip_snat_for_lb = 1; ct_lb(<var>args</var>);</code>. </li> <li> @@ -2797,6 +2807,9 @@ icmp6 { If the router is configured to force SNAT any load-balanced packets, the above action will be replaced by <code>flags.force_snat_for_lb = 1; ct_dnat;</code>. + If the load balancig rule is configured with <code>lb_skip_snat</code> + set to true, the above action will be replaced by + <code>flags.skip_snat_for_lb = 1; ct_dnat;</code>. </li> <li> @@ -3829,6 +3842,16 @@ nd_ns { </p> </li> + <li> + <p> + If the Gateway router in the OVN Northbound database has been + configured to skip SNAT a packet (that has been previously + load-balanced), a priority-120 flow matches + <code>flags.skip_snat_for_lb == 1 && ip</code> with an + action <code>next;</code>. + </p> + </li> + <li> <p> If the Gateway router in the OVN Northbound database has been diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c index 9839b8c4f..cc07e3a21 100644 --- a/northd/ovn-northd.c +++ b/northd/ovn-northd.c @@ -8576,7 +8576,7 @@ get_force_snat_ip(struct ovn_datapath *od, const char *key_type, static void add_router_lb_flow(struct hmap *lflows, struct ovn_datapath *od, struct ds *match, struct ds *actions, int priority, - bool force_snat_for_lb, struct ovn_lb_vip *lb_vip, + int snat_type, struct ovn_lb_vip *lb_vip, const char *proto, struct nbrec_load_balancer *lb, struct shash *meter_groups, struct sset *nat_entries) { @@ -8585,8 +8585,9 @@ add_router_lb_flow(struct hmap *lflows, struct ovn_datapath *od, /* A match and actions for new connections. */ char *new_match = xasprintf("ct.new && %s", ds_cstr(match)); - if (force_snat_for_lb) { - char *new_actions = xasprintf("flags.force_snat_for_lb = 1; %s", + if (snat_type) { + char *new_actions = xasprintf("flags.%s_snat_for_lb = 1; %s", + snat_type == 2 ? "skip" : "force", ds_cstr(actions)); ovn_lflow_add_with_hint(lflows, od, S_ROUTER_IN_DNAT, priority, new_match, new_actions, &lb->header_); @@ -8598,11 +8599,12 @@ add_router_lb_flow(struct hmap *lflows, struct ovn_datapath *od, /* A match and actions for established connections. */ char *est_match = xasprintf("ct.est && %s", ds_cstr(match)); - if (force_snat_for_lb) { + if (snat_type) { + char *est_actions = xasprintf("flags.%s_snat_for_lb = 1; ct_dnat;", + snat_type == 2 ? "skip" : "force"); ovn_lflow_add_with_hint(lflows, od, S_ROUTER_IN_DNAT, priority, - est_match, - "flags.force_snat_for_lb = 1; ct_dnat;", - &lb->header_); + est_match, est_actions, &lb->header_); + free(est_actions); } else { ovn_lflow_add_with_hint(lflows, od, S_ROUTER_IN_DNAT, priority, est_match, "ct_dnat;", &lb->header_); @@ -8675,11 +8677,13 @@ add_router_lb_flow(struct hmap *lflows, struct ovn_datapath *od, ds_put_format(&undnat_match, ") && outport == %s && " "is_chassis_resident(%s)", od->l3dgw_port->json_key, od->l3redirect_port->json_key); - if (force_snat_for_lb) { + if (snat_type) { + char *action = xasprintf("flags.%s_snat_for_lb = 1; ct_dnat;", + snat_type == 2 ? "skip" : "force"); ovn_lflow_add_with_hint(lflows, od, S_ROUTER_OUT_UNDNAT, 120, - ds_cstr(&undnat_match), - "flags.force_snat_for_lb = 1; ct_dnat;", + ds_cstr(&undnat_match), action, &lb->header_); + free(action); } else { ovn_lflow_add_with_hint(lflows, od, S_ROUTER_OUT_UNDNAT, 120, ds_cstr(&undnat_match), "ct_dnat;", @@ -8706,6 +8710,13 @@ build_lrouter_lb_flows(struct hmap *lflows, struct ovn_datapath *od, ovn_northd_lb_find(lbs, &nb_lb->header_.uuid); ovs_assert(lb); + bool lb_skip_snat = smap_get_bool(&nb_lb->options, "lb_skip_snat", + false); + if (lb_skip_snat) { + ovn_lflow_add(lflows, od, S_ROUTER_OUT_SNAT, 120, + "flags.skip_snat_for_lb == 1 && ip", "next;"); + } + for (size_t j = 0; j < lb->n_vips; j++) { struct ovn_lb_vip *lb_vip = &lb->vips[j]; struct ovn_northd_lb_vip *lb_vip_nb = &lb->vips_nb[j]; @@ -8767,11 +8778,16 @@ build_lrouter_lb_flows(struct hmap *lflows, struct ovn_datapath *od, ds_put_format(match, " && is_chassis_resident(%s)", od->l3redirect_port->json_key); } - bool force_snat_for_lb = - lb_force_snat_ip || od->lb_force_snat_router_ip; + + int snat_type = 0; + if (lb_skip_snat) { + snat_type = 2; + } else if (lb_force_snat_ip || od->lb_force_snat_router_ip) { + snat_type = 1; + } add_router_lb_flow(lflows, od, match, actions, prio, - force_snat_for_lb, lb_vip, proto, - nb_lb, meter_groups, nat_entries); + snat_type, lb_vip, proto, nb_lb, + meter_groups, nat_entries); } } sset_destroy(&all_ips); diff --git a/northd/ovn_northd.dl b/northd/ovn_northd.dl index 0063021e1..8dc07c02f 100644 --- a/northd/ovn_northd.dl +++ b/northd/ovn_northd.dl @@ -5367,6 +5367,16 @@ for (&Router(.lr = lr)) { .external_ids = map_empty()) } +Flow(.logical_datapath = lr, + .stage = s_ROUTER_OUT_SNAT(), + .priority = 120, + .__match = "flags.skip_snat_for_lb == 1 && ip", + .actions = "next;", + .external_ids = stage_hint(lb._uuid)) :- + LogicalRouterLB(lr, lb), + lb.options.get_bool_def("lb_skip_snat", false) + . + function lrouter_nat_is_stateless(nat: NAT): bool = { Some{"true"} == nat.nat.options.get("stateless") } @@ -6010,14 +6020,15 @@ for (RouterLBVIP( (Some{gwport}, true) -> " && is_chassis_resident(${redirect_port_name})", _ -> "" } in - var force_snat_for_lb = force_snat_for_lb(lr) in + var snat_for_lb = snat_for_lb(lr, lb) in { /* A match and actions for established connections. */ var est_match = "ct.est && " ++ __match in var actions = - match (force_snat_for_lb) { - true -> "flags.force_snat_for_lb = 1; ct_dnat;", - false -> "ct_dnat;" + match (snat_for_lb) { + 2 -> "flags.skip_snat_for_lb = 1; ct_dnat;", + 1 -> "flags.force_snat_for_lb = 1; ct_dnat;", + _ -> "ct_dnat;" } in Flow(.logical_datapath = lr._uuid, .stage = s_ROUTER_IN_DNAT(), @@ -6076,9 +6087,10 @@ for (RouterLBVIP( ") && outport == ${json_string_escape(gwport.name)} && " "is_chassis_resident(${redirect_port_name})" in var action = - match (force_snat_for_lb) { - true -> "flags.force_snat_for_lb = 1; ct_dnat;", - false -> "ct_dnat;" + match (snat_for_lb) { + 2 -> "flags.skip_snat_for_lb = 1; ct_dnat;", + 1 -> "flags.force_snat_for_lb = 1; ct_dnat;", + _ -> "ct_dnat;" } in Flow(.logical_datapath = lr._uuid, .stage = s_ROUTER_OUT_UNDNAT(), @@ -6113,7 +6125,11 @@ Flow(.logical_datapath = r.lr._uuid, _ -> "" }, var priority = if (lbvip.vip_port != 0) 120 else 110, - var force_snat = if (force_snat_for_lb(r.lr)) "flags.force_snat_for_lb = 1; " else "", + var force_snat = match (snat_for_lb(r.lr, lb)) { + 2 -> "flags.skip_snat_for_lb = 1; ", + 1 -> "flags.force_snat_for_lb = 1; ", + _ -> "" + }, var actions = build_lb_vip_actions(lbvip, s_ROUTER_OUT_SNAT(), force_snat). diff --git a/tests/ovn-northd.at b/tests/ovn-northd.at index 96476497d..c63b514a9 100644 --- a/tests/ovn-northd.at +++ b/tests/ovn-northd.at @@ -2847,6 +2847,29 @@ AT_CHECK([grep "lr_out_snat" lr0flows | sort], [0], [dnl table=1 (lr_out_snat ), priority=120 , match=(nd_ns), action=(next;) ]) +check ovn-nbctl --wait=sb lb-add lb2 10.0.0.20:80 10.0.0.40:8080 +check ovn-nbctl --wait=sb set load_balancer lb2 options:lb_skip_snat=true +check ovn-nbctl lr-lb-add lr0 lb2 +check ovn-nbctl --wait=sb lb-del lb1 +ovn-sbctl dump-flows lr0 > lr0flows + +AT_CHECK([grep "lr_in_unsnat" lr0flows | sort], [0], [dnl + table=5 (lr_in_unsnat ), priority=0 , match=(1), action=(next;) + table=5 (lr_in_unsnat ), priority=110 , match=(inport == "lr0-public" && ip4.dst == 172.168.0.100), action=(ct_snat;) + table=5 (lr_in_unsnat ), priority=110 , match=(inport == "lr0-sw0" && ip4.dst == 10.0.0.1), action=(ct_snat;) + table=5 (lr_in_unsnat ), priority=110 , match=(inport == "lr0-sw1" && ip4.dst == 20.0.0.1), action=(ct_snat;) + table=5 (lr_in_unsnat ), priority=110 , match=(inport == "lr0-sw1" && ip6.dst == bef0::1), action=(ct_snat;) +]) + +AT_CHECK([grep "lr_in_dnat" lr0flows | grep skip_snat_for_lb | sort], [0], [dnl + table=6 (lr_in_dnat ), priority=120 , match=(ct.est && ip && ip4.dst == 10.0.0.20 && tcp && tcp.dst == 80), action=(flags.skip_snat_for_lb = 1; ct_dnat;) + table=6 (lr_in_dnat ), priority=120 , match=(ct.new && ip && ip4.dst == 10.0.0.20 && tcp && tcp.dst == 80), action=(flags.skip_snat_for_lb = 1; ct_lb(backends=10.0.0.40:8080);) +]) + +AT_CHECK([grep "lr_out_snat" lr0flows | grep skip_snat_for_lb | sort], [0], [dnl + table=1 (lr_out_snat ), priority=120 , match=(flags.skip_snat_for_lb == 1 && ip), action=(next;) +]) + AT_CLEANUP ]) @@ -2950,4 +2973,4 @@ wait_row_count FDB 0 ovn-sbctl list FDB AT_CLEANUP -]) \ No newline at end of file +]) -- 2.30.2 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
