Neigh suppression

.clang-format

@@ -71,23 +71,26 @@ EmptyLineBeforeAccessModifier: LogicalBlock
 ExperimentalAutoDetectBinPacking: false
 FixNamespaceComments: false
 ForEachMacros:
+  - EC_COMP_FOREACH
   - LIST_FOREACH
   - LIST_FOREACH_SAFE
+  - RB_FOREACH
+  - RNODE_FOREACH_RE
   - RTE_ETH_FOREACH_DEV
+  - RTE_ETH_FOREACH_MATCHING_DEV
   - RTE_LCORE_FOREACH
   - SLIST_FOREACH
   - SLIST_FOREACH_SAFE
   - STAILQ_FOREACH
   - STAILQ_FOREACH_SAFE
   - TAILQ_FOREACH
   - TAILQ_FOREACH_SAFE
-  - rte_graph_foreach_node
   - gr_api_client_stream_foreach
+  - gr_flags_foreach
+  - nexthop_type_ops_foreach
+  - rte_graph_foreach_node
   - vec_foreach
   - vec_foreach_ref
-  - gr_nh_flags_foreach
-IfMacros:
-  - KJ_IF_MAYBE
 IncludeBlocks: Regroup
 IncludeCategories:
   - Regex:           '^".*'

.github/workflows/check.yml

@@ -87,7 +87,7 @@ jobs:
           sudo apt-get install -qy --no-install-recommends \
             make gcc gdb ccache ninja-build meson git scdoc inotify-tools \
             libibverbs-dev libasan8 libcmocka-dev libedit-dev libarchive-dev \
-            libevent-dev libmnl-dev libnuma-dev python3-pyelftools \
+            libevent-dev libmnl-dev libnuma-dev python3-pyelftools arping \
             socat tcpdump traceroute graphviz iproute2 iputils-ping ndisc6 jq \
             dnsmasq systemd-coredump abigail-tools \
             "linux-modules-extra-$(uname -r)"

README.md

@@ -287,13 +287,13 @@ In order to run the `smoke-tests`, `lint`, `check-patches` and `update-graph`
 targets, you'll need additional packages:
 
 ```sh
-dnf install gawk gdb clang-tools-extra jq codespell curl traceroute graphviz ndisc6 abidiff inotify-tools
+dnf install gawk gdb clang-tools-extra iputils jq codespell curl traceroute graphviz ndisc6 abidiff inotify-tools
 ```
 
 or
 
 ```sh
-apt install gawk gdb clang-format jq codespell curl traceroute graphviz ndisc6 abigail-tools inotify-tools
+apt install arping gawk gdb clang-format jq codespell curl traceroute graphviz ndisc6 abigail-tools inotify-tools
 ```
 
 ### Build

api/gr_api.h

@@ -11,7 +11,7 @@
 #include <stdlib.h>
 
 // Must be bumped when making non-backward compatible changes in API headers
-#define GR_API_VERSION 5
+#define GR_API_VERSION 6
 
 // API request header.
 struct gr_api_request {

api/gr_macro.h

@@ -5,6 +5,7 @@
 
 #include <errno.h>
 #include <limits.h>
+#include <stdint.h>
 
 // Get number of elements in a static array.
 #define ARRAY_DIM(array) (sizeof(array) / sizeof(array[0]))
@@ -48,3 +49,7 @@
 
 #define GR_SYMBOL_FORBIDDEN(func, new_func)                                                        \
 	sorry_##func##_is_a_banned_function_use_##new_func##_instead
+
+#define gr_flags_foreach(f, flags)                                                                 \
+	for (uint64_t __bit = 0, f = 1ULL; __bit < sizeof(flags) * CHAR_BIT; f = 1ULL << ++__bit)  \
+		if (flags & f)

cli/complete.c

@@ -115,7 +115,7 @@ int bash_complete(struct ec_node *cmdlist) {
 
 	count = 0;
 	comp_width = 0;
-	EC_COMP_FOREACH(item, cmpl, EC_COMP_FULL | EC_COMP_PARTIAL) {
+	EC_COMP_FOREACH (item, cmpl, EC_COMP_FULL | EC_COMP_PARTIAL) {
 		int w = strlen(ec_comp_item_get_str(item));
 		if (w > comp_width)
 			comp_width = w;
@@ -131,7 +131,7 @@ int bash_complete(struct ec_node *cmdlist) {
 		colon_prefix = last_colon - comp_word + 1;
 	comp_width -= colon_prefix;
 
-	EC_COMP_FOREACH(item, cmpl, EC_COMP_FULL | EC_COMP_PARTIAL) {
+	EC_COMP_FOREACH (item, cmpl, EC_COMP_FULL | EC_COMP_PARTIAL) {
 		const char *choice = ec_comp_item_get_str(item) + colon_prefix;
 		const char *help = find_help(item);
 		if (count > 1 && help != NULL) {

cli/exec.c

@@ -98,7 +98,7 @@ get_suggestions(const struct ec_node *cmdlist, const char *cmdline, unsigned *po
 				goto out;
 
 			struct ec_comp_item *i;
-			EC_COMP_FOREACH(i, c, EC_COMP_FULL) {
+			EC_COMP_FOREACH (i, c, EC_COMP_FULL) {
 				if (ec_strvec_add(sug, ec_comp_item_get_str(i)) < 0)
 					goto out;
 			}

frr/rt_grout.c

@@ -654,7 +654,7 @@ static enum zebra_dplane_result grout_add_nexthop_group(struct zebra_dplane_ctx
 static enum zebra_dplane_result grout_del_nexthop(uint32_t nh_id) {
 	gr_log_debug("nh_id %u", nh_id);
 
-	struct gr_nh_del_req req = {.missing_ok = true, .nh_id = nh_id};
+	struct gr_nh_del_req req = {.missing_ok = true, .nh = {.nh_id = nh_id}};
 
 	if (grout_client_send_recv(GR_NH_DEL, sizeof(req), &req, NULL) < 0)
 		return ZEBRA_DPLANE_REQUEST_FAILURE;
@@ -931,16 +931,80 @@ void grout_nexthop_group_add(struct gr_nexthop *gr_nh, bool startup) {
 	);
 }
 
+static void grout_neigh_notify(bool new, struct gr_nexthop *gr_nh) {
+	const struct gr_nexthop_info_l3 *l3;
+	static const struct ethaddr zero_mac = {};
+	struct zebra_dplane_ctx *ctx;
+	struct ethaddr mac;
+	struct ipaddr ip;
+
+	if (gr_nh->type != GR_NH_T_L3)
+		return;
+
+	l3 = (const struct gr_nexthop_info_l3 *)gr_nh->info;
+
+	if (l3->af != GR_AF_IP4 && l3->af != GR_AF_IP6)
+		return;
+	if (l3->flags & (GR_NH_F_LOCAL | GR_NH_F_LINK | GR_NH_F_MCAST | GR_NH_F_REMOTE))
+		return;
+	if (new && memcmp(&l3->mac, &zero_mac, sizeof(zero_mac)) == 0)
+		return;
+
+	memset(&ip, 0, sizeof(ip));
+	if (l3->af == GR_AF_IP4) {
+		ip.ipa_type = IPADDR_V4;
+		memcpy(&ip.ipaddr_v4, &l3->ipv4, sizeof(ip.ipaddr_v4));
+	} else {
+		ip.ipa_type = IPADDR_V6;
+		memcpy(&ip.ipaddr_v6, &l3->ipv6, sizeof(ip.ipaddr_v6));
+	}
+	memcpy(&mac, &l3->mac, sizeof(mac));
+
+	gr_log_debug(
+		"%s neigh iface=%u %pIA %pEA", new ? "add" : "del", gr_nh->iface_id, &ip, &mac
+	);
+
+	ctx = dplane_ctx_alloc();
+	dplane_ctx_set_op(ctx, new ? DPLANE_OP_NEIGH_INSTALL : DPLANE_OP_NEIGH_DELETE);
+	dplane_ctx_set_ns_id(ctx, GROUT_NS);
+	dplane_ctx_set_ifindex(ctx, ifindex_grout_to_frr(gr_nh->iface_id));
+	dplane_ctx_neigh_set_ipaddr(ctx, &ip);
+	dplane_ctx_neigh_set_mac(ctx, &mac);
+	dplane_ctx_neigh_set_ndm_state(ctx, NUD_REACHABLE);
+	dplane_ctx_neigh_set_ndm_family(ctx, l3->af == GR_AF_IP4 ? AF_INET : AF_INET6);
+	dplane_ctx_neigh_set_l2_len(ctx, ETH_ALEN);
+#if CURRENT_FRR_VERSION >= MAKE_FRRVERSION(10, 6, 0)
+	dplane_ctx_neigh_set_is_own(ctx, false);
+#else
+	dplane_ctx_neigh_set_is_ext(ctx, false);
+#endif
+	dplane_ctx_neigh_set_is_router(ctx, false);
+	dplane_ctx_neigh_set_dp_static(ctx, false);
+	dplane_ctx_neigh_set_local_inactive(ctx, false);
+
+	dplane_provider_enqueue_to_zebra(ctx);
+}
+
 void grout_nexthop_change(bool new, struct gr_nexthop *gr_nh, bool startup) {
 	struct nexthop *nh = NULL;
 	afi_t afi = AFI_UNSPEC;
 	int family, type;
 
-	gr_log_debug("%s nh_id %u", new ? "add" : "del", gr_nh->nh_id);
+	gr_log_debug(
+		"%s nh_id %u origin %s",
+		new ? "add" : "del",
+		gr_nh->nh_id,
+		gr_nh_origin_name(gr_nh->origin)
+	);
+
+	grout_neigh_notify(new, gr_nh);
 
-	// XXX: grout is optional to have an ID for nexthop
-	// but in FRR, it's mandatory
+	if (gr_nh->origin == GR_NH_ORIGIN_NEIGH) {
+		gr_log_debug("dynamic neighbor learn, skip");
+		return;
+	}
 	if (gr_nh->nh_id == 0) {
+		// Nexthop IDs are optional in grout, but mandatory in FRR.
 		gr_log_debug("nexthop without ID, skip");
 		return;
 	}
@@ -1095,6 +1159,90 @@ enum zebra_dplane_result grout_macfdb_update_ctx(struct zebra_dplane_ctx *ctx) {
 	return ret == 0 ? ZEBRA_DPLANE_REQUEST_SUCCESS : ZEBRA_DPLANE_REQUEST_FAILURE;
 }
 
+static void neigh_install_nexthop(struct zebra_dplane_ctx *ctx, const struct ipaddr *addr) {
+	uint16_t iface_id = ifindex_frr_to_grout(dplane_ctx_get_ifindex(ctx));
+	const struct ethaddr *mac = dplane_ctx_neigh_get_mac(ctx);
+	struct gr_nexthop_info_l3 *l3;
+	struct gr_nh_add_req *req;
+	size_t len;
+
+	if (iface_id == GR_IFACE_ID_UNDEF)
+		return;
+
+	len = sizeof(*req) + sizeof(*l3);
+	req = calloc(1, len);
+	if (req == NULL) {
+		gr_log_err("calloc: %s", strerror(errno));
+		return;
+	}
+
+	req->exist_ok = true;
+	req->nh.type = GR_NH_T_L3;
+	req->nh.origin = zebra2origin(dplane_ctx_get_type(ctx));
+	req->nh.iface_id = iface_id;
+	l3 = (struct gr_nexthop_info_l3 *)req->nh.info;
+	l3->flags = GR_NH_F_REMOTE;
+
+	switch (addr->ipa_type) {
+	case IPADDR_V4:
+		l3->af = GR_AF_IP4;
+		memcpy(&l3->ipv4, &addr->ipaddr_v4, sizeof(l3->ipv4));
+		break;
+	case IPADDR_V6:
+		l3->af = GR_AF_IP6;
+		memcpy(&l3->ipv6, &addr->ipaddr_v6, sizeof(l3->ipv6));
+		break;
+	default:
+		free(req);
+		return;
+	}
+	memcpy(&l3->mac, mac, sizeof(l3->mac));
+
+	gr_log_debug("install remote nh iface=%u %pIA %pEA", iface_id, addr, mac);
+	grout_client_send_recv(GR_NH_ADD, len, req, NULL);
+	free(req);
+}
+
+static void neigh_delete_nexthop(struct zebra_dplane_ctx *ctx, const struct ipaddr *addr) {
+	uint16_t iface_id = ifindex_frr_to_grout(dplane_ctx_get_ifindex(ctx));
+	struct gr_nexthop_info_l3 *l3;
+	struct gr_nh_del_req *req;
+	size_t len;
+
+	if (iface_id == GR_IFACE_ID_UNDEF)
+		return;
+
+	len = sizeof(*req) + sizeof(*l3);
+	req = calloc(1, len);
+	if (req == NULL) {
+		gr_log_err("calloc: %s", strerror(errno));
+		return;
+	}
+
+	req->missing_ok = true;
+	req->nh.type = GR_NH_T_L3;
+	req->nh.iface_id = iface_id;
+	l3 = (struct gr_nexthop_info_l3 *)req->nh.info;
+
+	switch (addr->ipa_type) {
+	case IPADDR_V4:
+		l3->af = GR_AF_IP4;
+		memcpy(&l3->ipv4, &addr->ipaddr_v4, sizeof(l3->ipv4));
+		break;
+	case IPADDR_V6:
+		l3->af = GR_AF_IP6;
+		memcpy(&l3->ipv6, &addr->ipaddr_v6, sizeof(l3->ipv6));
+		break;
+	default:
+		free(req);
+		return;
+	}
+
+	gr_log_debug("delete remote nh iface=%u %pIA", iface_id, addr);
+	grout_client_send_recv(GR_NH_DEL, len, req, NULL);
+	free(req);
+}
+
 enum zebra_dplane_result grout_neigh_update_ctx(struct zebra_dplane_ctx *ctx) {
 	const struct ipaddr *addr = dplane_ctx_neigh_get_ipaddr(ctx);
 	bool add = dplane_ctx_get_op(ctx) != DPLANE_OP_NEIGH_DELETE;
@@ -1115,9 +1263,12 @@ enum zebra_dplane_result grout_neigh_update_ctx(struct zebra_dplane_ctx *ctx) {
 		const struct ethaddr *mac = dplane_ctx_neigh_get_mac(ctx);
 		gr_log_debug("cache rmac vrf=%u %pIA %pEA", vrf_id, addr, mac);
 		l3vni_rmac_set(vrf_id, addr, mac);
+		// Install a remote nexthop for ARP/ND suppression.
+		neigh_install_nexthop(ctx, addr);
 	} else {
 		gr_log_debug("uncache rmac vrf=%u %pIA", vrf_id, addr);
 		l3vni_rmac_del(vrf_id, addr);
+		neigh_delete_nexthop(ctx, addr);
 	}
 
 	return ZEBRA_DPLANE_REQUEST_SUCCESS;

frr/zebra_dplane_grout.c

@@ -244,7 +244,7 @@ static void grout_sync_poll_marker(struct event *e) {
 	if (table) {
 		rn = route_node_lookup(table, &grout_sync_marker_prefix);
 		if (rn) {
-			RNODE_FOREACH_RE(rn, re) {
+			RNODE_FOREACH_RE (rn, re) {
 				if (CHECK_FLAG(re->status, ROUTE_ENTRY_REMOVED))
 					continue;
 				if (re->tag == GROUT_SYNC_MARKER_TAG
@@ -944,7 +944,7 @@ static void grout_ns_reset(void) {
 	struct vrf *default_vrf, *vrf;
 	struct interface *ifp;
 
-	RB_FOREACH(vrf, vrf_id_head, &vrfs_by_id) {
+	RB_FOREACH (vrf, vrf_id_head, &vrfs_by_id) {
 		FOR_ALL_INTERFACES(vrf, ifp) {
 			if_down(ifp);
 		}

modules/infra/api/gr_infra.h

@@ -34,6 +34,7 @@ typedef enum : uint16_t {
 	GR_IFACE_F_PACKET_TRACE = GR_BIT16(2),
 	GR_IFACE_F_SNAT_STATIC = GR_BIT16(3),
 	GR_IFACE_F_SNAT_DYNAMIC = GR_BIT16(4),
+	GR_IFACE_F_NEIGH_SNOOP = GR_BIT16(5),
 } gr_iface_flags_t;
 
 // Interface state flags.