lib: Handle if up/down and vrf enable/disable events

Properly notice when we get if up/down and vrf enable/disable
events and attempt to properly install nexthops as they
come in.

Ticket: CM20489
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

4 files changed, 219 insertions, 50 deletions

diff --git a/lib/nexthop_group.c b/lib/nexthop_group.c
index dc234bc45d..5ac38d6685 100644
--- a/lib/nexthop_group.c
+++ b/lib/nexthop_group.c
@@ -331,75 +331,78 @@ static void nexthop_group_unsave_nhop(struct nexthop_group_cmd *nhgc,
 	XFREE(MTYPE_TMP, nh);
 }
 
-DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
-      "[no] nexthop <A.B.C.D|X:X::X:X>$addr [INTERFACE]$intf [nexthop-vrf NAME$name]",
-      NO_STR
-      "Specify one of the nexthops in this ECMP group\n"
-      "v4 Address\n"
-      "v6 Address\n"
-      "Interface to use\n"
-      "If the nexthop is in a different vrf tell us\n"
-      "The nexthop-vrf Name\n")
+static bool nexthop_group_parse_nexthop(struct nexthop *nhop,
+					const union sockunion *addr,
+					const char *intf, const char *name)
 {
-	VTY_DECLVAR_CONTEXT(nexthop_group_cmd, nhgc);
 	struct vrf *vrf;
-	struct nexthop nhop;
-	struct nexthop *nh;
+
+	memset(nhop, 0, sizeof(*nhop));
 
 	if (name)
 		vrf = vrf_lookup_by_name(name);
 	else
 		vrf = vrf_lookup_by_id(VRF_DEFAULT);
 
-	if (!vrf) {
-		vty_out(vty, "Specified: %s is non-existent\n", name);
-		return CMD_WARNING;
-	}
+	if (!vrf)
+		return false;
 
-	memset(&nhop, 0, sizeof(nhop));
-	nhop.vrf_id = vrf->vrf_id;
+	nhop->vrf_id = vrf->vrf_id;
 
 	if (addr->sa.sa_family == AF_INET) {
-		nhop.gate.ipv4.s_addr = addr->sin.sin_addr.s_addr;
+		nhop->gate.ipv4.s_addr = addr->sin.sin_addr.s_addr;
 		if (intf) {
-			nhop.type = NEXTHOP_TYPE_IPV4_IFINDEX;
-			nhop.ifindex = ifname2ifindex(intf, vrf->vrf_id);
-			if (nhop.ifindex == IFINDEX_INTERNAL) {
-				vty_out(vty,
-					"Specified Intf %s does not exist in vrf: %s\n",
-					intf, vrf->name);
-				return CMD_WARNING;
-			}
+			nhop->type = NEXTHOP_TYPE_IPV4_IFINDEX;
+			nhop->ifindex = ifname2ifindex(intf, vrf->vrf_id);
+			if (nhop->ifindex == IFINDEX_INTERNAL)
+				return false;
 		} else
-			nhop.type = NEXTHOP_TYPE_IPV4;
+			nhop->type = NEXTHOP_TYPE_IPV4;
 	} else {
-		memcpy(&nhop.gate.ipv6, &addr->sin6.sin6_addr, 16);
+		memcpy(&nhop->gate.ipv6, &addr->sin6.sin6_addr, 16);
 		if (intf) {
-			nhop.type = NEXTHOP_TYPE_IPV6_IFINDEX;
-			nhop.ifindex = ifname2ifindex(intf, vrf->vrf_id);
-			if (nhop.ifindex == IFINDEX_INTERNAL) {
-				vty_out(vty,
-					"Specified Intf %s does not exist in vrf: %s\n",
-					intf, vrf->name);
-				return CMD_WARNING;
-			}
-		} else {
-			if (IN6_IS_ADDR_LINKLOCAL(&nhop.gate.ipv6)) {
-				vty_out(vty,
-					"Specified a v6 LL with no interface, rejecting\n");
-				return CMD_WARNING_CONFIG_FAILED;
-			}
-			nhop.type = NEXTHOP_TYPE_IPV6;
-		}
+			nhop->type = NEXTHOP_TYPE_IPV6_IFINDEX;
+			nhop->ifindex = ifname2ifindex(intf, vrf->vrf_id);
+			if (nhop->ifindex == IFINDEX_INTERNAL)
+				return false;
+		} else
+			nhop->type = NEXTHOP_TYPE_IPV6;
+	}
+
+	return true;
+}
+
+DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
+      "[no] nexthop <A.B.C.D|X:X::X:X>$addr [INTERFACE]$intf [nexthop-vrf NAME$name]",
+      NO_STR
+      "Specify one of the nexthops in this ECMP group\n"
+      "v4 Address\n"
+      "v6 Address\n"
+      "Interface to use\n"
+      "If the nexthop is in a different vrf tell us\n"
+      "The nexthop-vrf Name\n")
+{
+	VTY_DECLVAR_CONTEXT(nexthop_group_cmd, nhgc);
+	struct nexthop nhop;
+	struct nexthop *nh;
+	bool legal;
+
+	legal = nexthop_group_parse_nexthop(&nhop, addr, intf, name);
+
+	if (nhop.type == NEXTHOP_TYPE_IPV6
+	    && IN6_IS_ADDR_LINKLOCAL(&nhop.gate.ipv6)) {
+		vty_out(vty,
+			"Specified a v6 LL with no interface, rejecting\n");
+		return CMD_WARNING_CONFIG_FAILED;
 	}
 
 	nh = nexthop_exists(&nhgc->nhg, &nhop);
 
 	if (no) {
+		nexthop_group_unsave_nhop(nhgc, name, addr, intf);
 		if (nh) {
 			nexthop_del(&nhgc->nhg, nh);
 
-			nexthop_group_unsave_nhop(nhgc, name, addr, intf);
 			if (nhg_hooks.del_nexthop)
 				nhg_hooks.del_nexthop(nhgc, nh);
 
@@ -407,14 +410,16 @@ DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
 		}
 	} else if (!nh) {
 		/* must be adding new nexthop since !no and !nexthop_exists */
-		nh = nexthop_new();
+		if (legal) {
+			nh = nexthop_new();
 
-		memcpy(nh, &nhop, sizeof(nhop));
-		nexthop_add(&nhgc->nhg.nexthop, nh);
+			memcpy(nh, &nhop, sizeof(nhop));
+			nexthop_add(&nhgc->nhg.nexthop, nh);
+		}
 
 		nexthop_group_save_nhop(nhgc, name, addr, intf);
 
-		if (nhg_hooks.add_nexthop)
+		if (legal && nhg_hooks.add_nexthop)
 			nhg_hooks.add_nexthop(nhgc, nh);
 	}
 
@@ -504,6 +509,152 @@ static int nexthop_group_write(struct vty *vty)
 	return 1;
 }
 
+void nexthop_group_enable_vrf(struct vrf *vrf)
+{
+	struct nexthop_group_cmd *nhgc;
+	struct nexthop_hold *nhh;
+
+	RB_FOREACH (nhgc, nhgc_entry_head, &nhgc_entries) {
+		struct listnode *node;
+
+		for (ALL_LIST_ELEMENTS_RO(nhgc->nhg_list, node, nhh)) {
+			struct nexthop nhop;
+			struct nexthop *nh;
+
+			if (!nexthop_group_parse_nexthop(&nhop, &nhh->addr,
+							 nhh->intf,
+							 nhh->nhvrf_name))
+				continue;
+
+			nh = nexthop_exists(&nhgc->nhg, &nhop);
+
+			if (nh)
+				continue;
+
+			if (nhop.vrf_id != vrf->vrf_id)
+				continue;
+
+			nh = nexthop_new();
+
+			memcpy(nh, &nhop, sizeof(nhop));
+			nexthop_add(&nhgc->nhg.nexthop, nh);
+
+			if (nhg_hooks.add_nexthop)
+				nhg_hooks.add_nexthop(nhgc, nh);
+		}
+	}
+}
+
+void nexthop_group_disable_vrf(struct vrf *vrf)
+{
+	struct nexthop_group_cmd *nhgc;
+	struct nexthop_hold *nhh;
+
+	RB_FOREACH (nhgc, nhgc_entry_head, &nhgc_entries) {
+		struct listnode *node;
+
+		for (ALL_LIST_ELEMENTS_RO(nhgc->nhg_list, node, nhh)) {
+			struct nexthop nhop;
+			struct nexthop *nh;
+
+			if (!nexthop_group_parse_nexthop(&nhop, &nhh->addr,
+							 nhh->intf,
+							 nhh->nhvrf_name))
+				continue;
+
+			nh = nexthop_exists(&nhgc->nhg, &nhop);
+
+			if (!nh)
+				continue;
+
+			if (nh->vrf_id != vrf->vrf_id)
+				continue;
+
+			nexthop_del(&nhgc->nhg, nh);
+
+			if (nhg_hooks.del_nexthop)
+				nhg_hooks.del_nexthop(nhgc, nh);
+
+			nexthop_free(nh);
+		}
+	}
+}
+
+void nexthop_group_interface_state_change(struct interface *ifp,
+					  ifindex_t oldifindex)
+{
+	struct nexthop_group_cmd *nhgc;
+	struct nexthop_hold *nhh;
+
+	RB_FOREACH (nhgc, nhgc_entry_head, &nhgc_entries) {
+		struct listnode *node;
+		struct nexthop *nh;
+
+		if (if_is_up(ifp)) {
+			for (ALL_LIST_ELEMENTS_RO(nhgc->nhg_list, node, nhh)) {
+				struct nexthop nhop;
+
+				if (!nexthop_group_parse_nexthop(
+					    &nhop, &nhh->addr, nhh->intf,
+					    nhh->nhvrf_name))
+					continue;
+
+				switch (nhop.type) {
+				case NEXTHOP_TYPE_IPV4:
+				case NEXTHOP_TYPE_IPV6:
+				case NEXTHOP_TYPE_BLACKHOLE:
+					continue;
+				case NEXTHOP_TYPE_IFINDEX:
+				case NEXTHOP_TYPE_IPV4_IFINDEX:
+				case NEXTHOP_TYPE_IPV6_IFINDEX:
+					break;
+				}
+				nh = nexthop_exists(&nhgc->nhg, &nhop);
+
+				if (nh)
+					continue;
+
+				if (ifp->ifindex != nhop.ifindex)
+					continue;
+
+				nh = nexthop_new();
+
+				memcpy(nh, &nhop, sizeof(nhop));
+				nexthop_add(&nhgc->nhg.nexthop, nh);
+
+				if (nhg_hooks.add_nexthop)
+					nhg_hooks.add_nexthop(nhgc, nh);
+			}
+		} else {
+			struct nexthop *next_nh;
+
+			for (nh = nhgc->nhg.nexthop; nh; nh = next_nh) {
+				next_nh = nh->next;
+				switch (nh->type) {
+				case NEXTHOP_TYPE_IPV4:
+				case NEXTHOP_TYPE_IPV6:
+				case NEXTHOP_TYPE_BLACKHOLE:
+					continue;
+				case NEXTHOP_TYPE_IFINDEX:
+				case NEXTHOP_TYPE_IPV4_IFINDEX:
+				case NEXTHOP_TYPE_IPV6_IFINDEX:
+					break;
+				}
+
+				if (oldifindex != nh->ifindex)
+					continue;
+
+				nexthop_del(&nhgc->nhg, nh);
+
+				if (nhg_hooks.del_nexthop)
+					nhg_hooks.del_nexthop(nhgc, nh);
+
+				nexthop_free(nh);
+			}
+		}
+	}
+}
+
 void nexthop_group_init(void (*new)(const char *name),
 			void (*add_nexthop)(const struct nexthop_group_cmd *nhg,
 					    const struct nexthop *nhop),
diff --git a/lib/nexthop_group.h b/lib/nexthop_group.h
index e9b670d537..a44f4e3542 100644
--- a/lib/nexthop_group.h
+++ b/lib/nexthop_group.h
@@ -94,6 +94,11 @@ void nexthop_group_init(
 			    const struct nexthop *nhop),
 	void (*delete)(const char *name));
 
+void nexthop_group_enable_vrf(struct vrf *vrf);
+void nexthop_group_disable_vrf(struct vrf *vrf);
+void nexthop_group_interface_state_change(struct interface *ifp,
+					  ifindex_t oldifindex);
+
 extern struct nexthop *nexthop_exists(struct nexthop_group *nhg,
 				      struct nexthop *nh);
 
diff --git a/lib/vrf.c b/lib/vrf.c
index b493f832f3..db539d375d 100644
--- a/lib/vrf.c
+++ b/lib/vrf.c
@@ -34,6 +34,7 @@
 #include "command.h"
 #include "ns.h"
 #include "privs.h"
+#include "nexthop_group.h"
 
 /* default VRF ID value used when VRF backend is not NETNS */
 #define VRF_DEFAULT_INTERNAL 0
@@ -269,6 +270,13 @@ int vrf_enable(struct vrf *vrf)
 	if (vrf_master.vrf_enable_hook)
 		(*vrf_master.vrf_enable_hook)(vrf);
 
+	/*
+	 * If we have any nexthop group entries that
+	 * are awaiting vrf initialization then
+	 * let's let people know about it
+	 */
+	nexthop_group_enable_vrf(vrf);
+
 	return 1;
 }
 
diff --git a/lib/zclient.c b/lib/zclient.c
index e1ce40ce70..48182d6b2c 100644
--- a/lib/zclient.c
+++ b/lib/zclient.c
@@ -37,6 +37,7 @@
 #include "mpls.h"
 #include "sockopt.h"
 #include "pbr.h"
+#include "nexthop_group.h"
 
 DEFINE_MTYPE_STATIC(LIB, ZCLIENT, "Zclient")
 DEFINE_MTYPE_STATIC(LIB, REDIST_INST, "Redistribution instance IDs")
@@ -1697,7 +1698,9 @@ struct interface *zebra_interface_link_params_read(struct stream *s)
 void zebra_interface_if_set_value(struct stream *s, struct interface *ifp)
 {
 	uint8_t link_params_status = 0;
+	ifindex_t old_ifindex;
 
+	old_ifindex = ifp->ifindex;
 	/* Read interface's index. */
 	if_set_index(ifp, stream_getl(s));
 	ifp->status = stream_getc(s);
@@ -1724,6 +1727,8 @@ void zebra_interface_if_set_value(struct stream *s, struct interface *ifp)
 		struct if_link_params *iflp = if_link_params_get(ifp);
 		link_params_set_value(s, iflp);
 	}
+
+	nexthop_group_interface_state_change(ifp, old_ifindex);
 }
 
 size_t zebra_interface_link_params_write(struct stream *s,