*: add srte color support in nhg

The nexthop group CLI can not configure color support.
Add a new option under nexthop command to configure an
srte color:

> nexthop-group 1
> [..]
>  nexthop 192.0.2.100 color 100

Add srte color support for nhg:
- Add NEXTHOP_GROUP_MESSAGE_COLOR support in NHG.
- Add ZAPI_NEXTHOP_MESSAGE_SRTE support in ZAPI.
- When checking for nexthop active, an SRTE policy with
the (color, nexthop ip) tuple will be looked ip.

Add a NHG sharp test for SRTE color:
- a NHG matching an SRTE policy is configured
- NHG sharp is extended to watch a given NHT color
> sharp watch nexthop 172.31.0.200 color 1
- Upon NHT call back, the NHG is re-added, and updates
the nexthop.

Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>

doc/user/nexthop_groups.rst

@@ -12,7 +12,7 @@ listing of ECMP nexthops used to forward packets.
    sub-mode where you can specify individual nexthops.  To exit this mode type
    exit or end as per normal conventions for leaving a sub-mode.
 
-.. clicmd:: nexthop [A.B.C.D|X:X::X:XX] [interface [onlink]] [nexthop-vrf NAME] [label LABELS]
+.. clicmd:: nexthop [A.B.C.D|X:X::X:XX] [interface [onlink]] [nexthop-vrf NAME] [label LABELS] [color (1-4294967295)]
 
    Create a v4 or v6 nexthop.  All normal rules for creating nexthops that you
    are used to are allowed here.  The syntax was intentionally kept the same as

lib/nexthop_group.c

@@ -31,6 +31,7 @@ struct nexthop_hold {
 	vni_t vni;
 	uint32_t weight;
 	char *backup_str;
+	uint32_t color;
 };
 
 struct nexthop_group_hooks {
@@ -51,7 +52,7 @@ nexthop_group_cmd_compare(const struct nexthop_group_cmd *nhgc1,
 RB_GENERATE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
 	    nexthop_group_cmd_compare)
 
-static struct nhgc_entry_head nhgc_entries;
+struct nhgc_entry_head nhgc_entries;
 
 static inline int
 nexthop_group_cmd_compare(const struct nexthop_group_cmd *nhgc1,
@@ -721,6 +722,23 @@ DEFPY(nexthop_group_ibgp,
 	return CMD_SUCCESS;
 }
 
+static void nhgc_configure_color(struct nexthop_group_cmd *nhgc, bool enable)
+{
+	if (enable ==
+	    !!CHECK_FLAG(nhgc->nhg.message, NEXTHOP_GROUP_MESSAGE_SRTE))
+		return;
+
+	if (enable)
+		SET_FLAG(nhgc->nhg.message, NEXTHOP_GROUP_MESSAGE_SRTE);
+	else
+		UNSET_FLAG(nhgc->nhg.message, NEXTHOP_GROUP_MESSAGE_SRTE);
+
+	SET_FLAG(nhgc->nhg.flags, NEXTHOP_GROUP_RESET_NHG);
+	if (nhg_hooks.modify)
+		nhg_hooks.modify(nhgc);
+	UNSET_FLAG(nhgc->nhg.flags, NEXTHOP_GROUP_RESET_NHG);
+}
+
 DEFPY(no_nexthop_group_backup, no_nexthop_group_backup_cmd,
       "no backup-group [WORD$name]",
       NO_STR
@@ -778,12 +796,11 @@ DEFPY(no_nexthop_group_resilience,
 	return CMD_SUCCESS;
 }
 
-static void nexthop_group_save_nhop(struct nexthop_group_cmd *nhgc,
-				    const char *nhvrf_name,
-				    const union sockunion *addr,
-				    const char *intf, bool onlink,
-				    const char *labels, const uint32_t weight,
-				    const char *backup_str)
+static void
+nexthop_group_save_nhop(struct nexthop_group_cmd *nhgc, const char *nhvrf_name,
+			const union sockunion *addr, const char *intf,
+			bool onlink, const char *labels, const uint32_t weight,
+			const char *backup_str, const uint32_t color)
 {
 	struct nexthop_hold *nh;
 
@@ -802,6 +819,8 @@ static void nexthop_group_save_nhop(struct nexthop_group_cmd *nhgc,
 
 	nh->weight = weight;
 
+	nh->color = color;
+
 	if (backup_str)
 		nh->backup_str = XSTRDUP(MTYPE_TMP, backup_str);
 
@@ -850,8 +869,8 @@ static bool nexthop_group_parse_nexthop(struct nexthop *nhop,
 					const union sockunion *addr,
 					const char *intf, bool onlink,
 					const char *name, const char *labels,
-					vni_t vni, int *lbl_ret,
-					uint32_t weight, const char *backup_str)
+					vni_t vni, int *lbl_ret, uint32_t weight,
+					const char *backup_str, uint32_t color)
 {
 	int ret = 0;
 	struct vrf *vrf;
@@ -918,6 +937,7 @@ static bool nexthop_group_parse_nexthop(struct nexthop *nhop,
 	}
 
 	nhop->weight = weight;
+	nhop->srte_color = color;
 
 	if (backup_str) {
 		/* Parse backup indexes */
@@ -939,9 +959,11 @@ static bool nexthop_group_parse_nexthop(struct nexthop *nhop,
 static bool nexthop_group_parse_nhh(struct nexthop *nhop,
 				    const struct nexthop_hold *nhh)
 {
-	return (nexthop_group_parse_nexthop(
-		nhop, nhh->addr, nhh->intf, nhh->onlink, nhh->nhvrf_name,
-		nhh->labels, nhh->vni, NULL, nhh->weight, nhh->backup_str));
+	return (nexthop_group_parse_nexthop(nhop, nhh->addr, nhh->intf,
+					    nhh->onlink, nhh->nhvrf_name,
+					    nhh->labels, nhh->vni, NULL,
+					    nhh->weight, nhh->backup_str,
+					    nhh->color));
 }
 
 DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
@@ -956,6 +978,7 @@ DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
 	   |vni (1-16777215) \
            |weight (1-255) \
            |backup-idx WORD \
+           |color (1-4294967295) \
 	}]",
       NO_STR
       "Specify one of the nexthops in this ECMP group\n"
@@ -973,7 +996,9 @@ DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
       "Weight to be used by the nexthop for purposes of ECMP\n"
       "Weight value to be used\n"
       "Specify backup nexthop indexes in another group\n"
-      "One or more indexes in the range (0-254) separated by ','\n")
+      "One or more indexes in the range (0-254) separated by ','\n"
+      SRTE_STR
+      SRTE_COLOR_STR)
 {
 	VTY_DECLVAR_CONTEXT(nexthop_group_cmd, nhgc);
 	struct nexthop nhop;
@@ -982,7 +1007,9 @@ DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
 	bool legal;
 	int num;
 	uint8_t backups[NEXTHOP_MAX_BACKUPS];
-	bool yes = !no;
+	bool yes = !no, color_config = false;
+	struct nexthop_hold *nhh;
+	struct listnode *node;
 
 	/* Pre-parse backup string to validate */
 	if (backup_idx) {
@@ -995,7 +1022,7 @@ DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
 
 	legal = nexthop_group_parse_nexthop(&nhop, addr, intf, !!onlink,
 					    vrf_name, label, vni, &lbl_ret,
-					    weight, backup_idx);
+					    weight, backup_idx, color);
 
 	if (nhop.type == NEXTHOP_TYPE_IPV6
 	    && IN6_IS_ADDR_LINKLOCAL(&nhop.gate.ipv6)) {
@@ -1058,10 +1085,18 @@ DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
 
 		/* Save config always */
 		nexthop_group_save_nhop(nhgc, vrf_name, addr, intf, !!onlink,
-					label, weight, backup_idx);
+					label, weight, backup_idx, color);
+		if (color)
+			nhgc_configure_color(nhgc, true);
 
 		if (legal && nhg_hooks.add_nexthop)
 			nhg_hooks.add_nexthop(nhgc, nh);
+	} else {
+		for (ALL_LIST_ELEMENTS_RO(nhgc->nhg_list, node, nhh)) {
+			if (nhh->color)
+				color_config = true;
+		}
+		nhgc_configure_color(nhgc, color_config);
 	}
 
 	return CMD_SUCCESS;
@@ -1134,6 +1169,9 @@ void nexthop_group_write_nexthop(struct vty *vty, const struct nexthop *nh)
 	if (nh->weight)
 		vty_out(vty, " weight %u", nh->weight);
 
+	if (nh->srte_color)
+		vty_out(vty, " color %u", nh->srte_color);
+
 	if (CHECK_FLAG(nh->flags, NEXTHOP_FLAG_HAS_BACKUP)) {
 		vty_out(vty, " backup-idx %d", nh->backup_idx[0]);
 
@@ -1191,6 +1229,9 @@ void nexthop_group_json_nexthop(json_object *j, const struct nexthop *nh)
 	if (nh->weight)
 		json_object_int_add(j, "weight", nh->weight);
 
+	if (nh->srte_color)
+		json_object_int_add(j, "color", nh->srte_color);
+
 	if (CHECK_FLAG(nh->flags, NEXTHOP_FLAG_HAS_BACKUP)) {
 		json_backups = json_object_new_array();
 		for (i = 0; i < nh->backup_num; i++)
@@ -1228,6 +1269,9 @@ static void nexthop_group_write_nexthop_internal(struct vty *vty,
 	if (nh->weight)
 		vty_out(vty, " weight %u", nh->weight);
 
+	if (nh->color)
+		vty_out(vty, " color %u", nh->color);
+
 	if (nh->backup_str)
 		vty_out(vty, " backup-idx %s", nh->backup_str);
 

lib/nexthop_group.h

@@ -41,6 +41,9 @@ struct nexthop_group {
 #define NEXTHOP_GROUP_FORCE_NH_CONFIG (1 << 3)
 #define NEXTHOP_GROUP_IBGP	      (1 << 4)
 	uint8_t flags;
+	/* nexthop group messages */
+#define NEXTHOP_GROUP_MESSAGE_SRTE (1 << 1)
+	uint8_t message;
 };
 
 struct nexthop_group *nexthop_group_new(void);
@@ -106,6 +109,7 @@ RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
 RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
 	     nexthop_group_cmd_compare)
 DECLARE_QOBJ_TYPE(nexthop_group_cmd);
+extern struct nhgc_entry_head nhgc_entries;
 
 /*
  * Initialize nexthop_groups.  If you are interested in when

lib/zclient.c

@@ -1148,6 +1148,7 @@ int zapi_srv6_locator_decode(struct stream *s, struct srv6_locator *l)
 static int zapi_nhg_encode(struct stream *s, int cmd, struct zapi_nhg *api_nhg)
 {
 	int i;
+	uint32_t api_message = 0;
 
 	if (cmd != ZEBRA_NHG_DEL && cmd != ZEBRA_NHG_ADD) {
 		flog_err(EC_LIB_ZAPI_ENCODE,
@@ -1174,6 +1175,9 @@ static int zapi_nhg_encode(struct stream *s, int cmd, struct zapi_nhg *api_nhg)
 	stream_putl(s, api_nhg->resilience.unbalanced_timer);
 
 	stream_putc(s, api_nhg->flags);
+	stream_putc(s, api_nhg->message);
+	if (CHECK_FLAG(api_nhg->message, ZAPI_NEXTHOP_MESSAGE_SRTE))
+		SET_FLAG(api_message, ZAPI_MESSAGE_SRTE);
 
 	if (cmd == ZEBRA_NHG_ADD) {
 		/* Nexthops */
@@ -1183,14 +1187,15 @@ static int zapi_nhg_encode(struct stream *s, int cmd, struct zapi_nhg *api_nhg)
 		stream_putw(s, api_nhg->nexthop_num);
 
 		for (i = 0; i < api_nhg->nexthop_num; i++)
-			zapi_nexthop_encode(s, &api_nhg->nexthops[i], 0, 0);
+			zapi_nexthop_encode(s, &api_nhg->nexthops[i], 0,
+					    api_message);
 
 		/* Backup nexthops */
 		stream_putw(s, api_nhg->backup_nexthop_num);
 
 		for (i = 0; i < api_nhg->backup_nexthop_num; i++)
 			zapi_nexthop_encode(s, &api_nhg->backup_nexthops[i], 0,
-					    0);
+					    api_message);
 	}
 
 	stream_putw_at(s, 0, stream_get_endp(s));

lib/zclient.h

@@ -489,6 +489,9 @@ struct zapi_nhg {
 
 	/* nexthop group flags */
 	uint8_t flags;
+	/* nexthop group message : definition from nexthop_group.h */
+#define ZAPI_NEXTHOP_MESSAGE_SRTE NEXTHOP_GROUP_MESSAGE_SRTE
+	uint8_t message;
 };
 
 /*

sharpd/sharp_nht.h

@@ -15,6 +15,8 @@ struct sharp_nh_tracker {
 	uint32_t nhop_num;
 
 	uint32_t updates;
+
+	uint32_t color;
 };
 
 extern struct sharp_nh_tracker *sharp_nh_tracker_get(struct prefix *p);

sharpd/sharp_vty.c

@@ -55,7 +55,7 @@ DEFPY(watch_redistribute, watch_redistribute_cmd,
 }
 
 DEFPY(watch_nexthop_v6, watch_nexthop_v6_cmd,
-      "sharp watch [vrf NAME$vrf_name] <nexthop$n X:X::X:X$nhop|import$import X:X::X:X/M$inhop>  [connected$connected]",
+      "sharp watch [vrf NAME$vrf_name] <nexthop$n X:X::X:X$nhop|import$import X:X::X:X/M$inhop>  [connected$connected] [color (1-4294967295)]",
       "Sharp routing Protocol\n"
       "Watch for changes\n"
       "The vrf we would like to watch if non-default\n"
@@ -64,11 +64,14 @@ DEFPY(watch_nexthop_v6, watch_nexthop_v6_cmd,
       "The v6 nexthop to signal for watching\n"
       "Watch for import check changes\n"
       "The v6 prefix to signal for watching\n"
-      "Should the route be connected\n")
+      "Should the route be connected\n"
+      SRTE_STR
+      SRTE_COLOR_STR)
 {
 	struct vrf *vrf;
 	struct prefix p;
 	bool type_import;
+	struct sharp_nh_tracker *nht;
 
 	if (!vrf_name)
 		vrf_name = VRF_DEFAULT_NAME;
@@ -91,15 +94,18 @@ DEFPY(watch_nexthop_v6, watch_nexthop_v6_cmd,
 		prefix_copy(&p, inhop);
 	}
 
-	sharp_nh_tracker_get(&p);
+	nht = sharp_nh_tracker_get(&p);
+	if (color)
+		nht->color = color;
+
 	sharp_zebra_nexthop_watch(&p, vrf->vrf_id, type_import,
 				  true, !!connected);
 
 	return CMD_SUCCESS;
 }
 
 DEFPY(watch_nexthop_v4, watch_nexthop_v4_cmd,
-      "sharp watch [vrf NAME$vrf_name] <nexthop$n A.B.C.D$nhop|import$import A.B.C.D/M$inhop> [connected$connected]",
+      "sharp watch [vrf NAME$vrf_name] <nexthop$n A.B.C.D$nhop|import$import A.B.C.D/M$inhop> [connected$connected] [color (1-4294967295)]",
       "Sharp routing Protocol\n"
       "Watch for changes\n"
       "The vrf we would like to watch if non-default\n"
@@ -108,11 +114,14 @@ DEFPY(watch_nexthop_v4, watch_nexthop_v4_cmd,
       "The v4 address to signal for watching\n"
       "Watch for import check changes\n"
       "The v4 prefix for import check to watch\n"
-      "Should the route be connected\n")
+      "Should the route be connected\n"
+      SRTE_STR
+      SRTE_COLOR_STR)
 {
 	struct vrf *vrf;
 	struct prefix p;
 	bool type_import;
+	struct sharp_nh_tracker *nht;
 
 	if (!vrf_name)
 		vrf_name = VRF_DEFAULT_NAME;
@@ -136,7 +145,9 @@ DEFPY(watch_nexthop_v4, watch_nexthop_v4_cmd,
 		prefix_copy(&p, inhop);
 	}
 
-	sharp_nh_tracker_get(&p);
+	nht = sharp_nh_tracker_get(&p);
+	if (color)
+		nht->color = color;
 	sharp_zebra_nexthop_watch(&p, vrf->vrf_id, type_import,
 				  true, !!connected);