isisd: update struct isis_route_info has multiple sr info by algorithm

Before this commit, there was only one sr psid info
included in route_info.

In fact, in RFC8667, Algorithm ID, which is a property of
Prefix-SID, has 8 bits of information. That is, each Prefix
can hold up to 256 Prefix-SIDs. This commit implements it.
The previously implemented single Prefix-SID will be
continued as Algorithm 0.

Signed-off-by: Hiroki Shirokura <hiroki.shirokura@linecorp.com>
Signed-off-by: Louis Scalbert <louis.scalbert@6wind.com>

isisd/isis_route.c

@@ -39,6 +39,8 @@
 
 DEFINE_MTYPE_STATIC(ISISD, ISIS_NEXTHOP,    "ISIS nexthop");
 DEFINE_MTYPE_STATIC(ISISD, ISIS_ROUTE_INFO, "ISIS route info");
+DEFINE_MTYPE_STATIC(ISISD, ISIS_ROUTE_TABLE_INFO, "ISIS route table info");
+
 
 DEFINE_HOOK(isis_route_update_hook,
 	    (struct isis_area * area, struct prefix *prefix,
@@ -51,8 +53,25 @@ static void isis_route_update(struct isis_area *area, struct prefix *prefix,
 			      struct prefix_ipv6 *src_p,
 			      struct isis_route_info *route_info);
 
-static struct isis_nexthop *isis_nexthop_create(int family, union g_addr *ip,
+static struct mpls_label_stack *
-						ifindex_t ifindex)
+label_stack_dup(const struct mpls_label_stack *const orig)
+{
+	struct mpls_label_stack *copy;
+	int array_size;
+
+	if (orig == NULL)
+		return NULL;
+
+	array_size = orig->num_labels * sizeof(mpls_label_t);
+	copy = XCALLOC(MTYPE_ISIS_NEXTHOP_LABELS,
+		       sizeof(struct mpls_label_stack) + array_size);
+	copy->num_labels = orig->num_labels;
+	memcpy(copy->label, orig->label, array_size);
+	return copy;
+}
+
+static struct isis_nexthop *
+isis_nexthop_create(int family, const union g_addr *const ip, ifindex_t ifindex)
 {
 	struct isis_nexthop *nexthop;
 
@@ -65,12 +84,40 @@ static struct isis_nexthop *isis_nexthop_create(int family, union g_addr *ip,
 	return nexthop;
 }
 
+static struct isis_nexthop *
+isis_nexthop_dup(const struct isis_nexthop *const orig)
+{
+	struct isis_nexthop *nexthop;
+
+	nexthop = isis_nexthop_create(orig->family, &orig->ip, orig->ifindex);
+	memcpy(nexthop->sysid, orig->sysid, ISIS_SYS_ID_LEN);
+	nexthop->sr = orig->sr;
+	nexthop->label_stack = label_stack_dup(orig->label_stack);
+
+	return nexthop;
+}
+
 void isis_nexthop_delete(struct isis_nexthop *nexthop)
 {
 	XFREE(MTYPE_ISIS_NEXTHOP_LABELS, nexthop->label_stack);
 	XFREE(MTYPE_ISIS_NEXTHOP, nexthop);
 }
 
+static struct list *isis_nexthop_list_dup(const struct list *orig)
+{
+	struct list *copy;
+	struct listnode *node;
+	struct isis_nexthop *nh;
+	struct isis_nexthop *nhcopy;
+
+	copy = list_new();
+	for (ALL_LIST_ELEMENTS_RO(orig, node, nh)) {
+		nhcopy = isis_nexthop_dup(nh);
+		listnode_add(copy, nhcopy);
+	}
+	return copy;
+}
+
 static struct isis_nexthop *nexthoplookup(struct list *nexthops, int family,
 					  union g_addr *ip, ifindex_t ifindex)
 {
@@ -238,9 +285,9 @@ isis_route_info_new(struct prefix *prefix, struct prefix_ipv6 *src_p,
 
 	rinfo->cost = cost;
 	rinfo->depth = depth;
-	rinfo->sr = *sr;
+	rinfo->sr_algo[sr->algorithm] = *sr;
-	rinfo->sr.nexthops = rinfo->nexthops;
+	rinfo->sr_algo[sr->algorithm].nexthops = rinfo->nexthops;
-	rinfo->sr.nexthops_backup =
+	rinfo->sr_algo[sr->algorithm].nexthops_backup =
 		rinfo->backup ? rinfo->backup->nexthops : NULL;
 
 	return rinfo;
@@ -248,6 +295,18 @@ isis_route_info_new(struct prefix *prefix, struct prefix_ipv6 *src_p,
 
 static void isis_route_info_delete(struct isis_route_info *route_info)
 {
+	for (int i = 0; i < SR_ALGORITHM_COUNT; i++) {
+		if (!route_info->sr_algo[i].present)
+			continue;
+
+		if (route_info->sr_algo[i].nexthops == route_info->nexthops)
+			continue;
+
+		route_info->sr_algo[i].nexthops->del =
+			(void (*)(void *))isis_nexthop_delete;
+		list_delete(&route_info->sr_algo[i].nexthops);
+	}
+
 	if (route_info->nexthops) {
 		route_info->nexthops->del =
 			(void (*)(void *))isis_nexthop_delete;
@@ -263,6 +322,27 @@ void isis_route_node_cleanup(struct route_table *table, struct route_node *node)
 		isis_route_info_delete(node->info);
 }
 
+struct isis_route_table_info *isis_route_table_info_alloc(uint8_t algorithm)
+{
+	struct isis_route_table_info *info;
+
+	info = XCALLOC(MTYPE_ISIS_ROUTE_TABLE_INFO, sizeof(*info));
+	info->algorithm = algorithm;
+	return info;
+}
+
+void isis_route_table_info_free(void *info)
+{
+	XFREE(MTYPE_ISIS_ROUTE_TABLE_INFO, info);
+}
+
+uint8_t isis_route_table_algorithm(const struct route_table *table)
+{
+	const struct isis_route_table_info *info = table->info;
+
+	return info ? info->algorithm : 0;
+}
+
 static bool isis_sr_psid_info_same(struct isis_sr_psid_info *new,
 				   struct isis_sr_psid_info *old)
 {
@@ -319,11 +399,23 @@ static int isis_route_info_same(struct isis_route_info *new,
 		return 0;
 	}
 
-	if (!isis_sr_psid_info_same(&new->sr, &old->sr)) {
+	for (int i = 0; i < SR_ALGORITHM_COUNT; i++) {
+		struct isis_sr_psid_info new_sr_algo;
+		struct isis_sr_psid_info old_sr_algo;
+
+		new_sr_algo = new->sr_algo[i];
+		old_sr_algo = old->sr_algo[i];
+
+		if (!isis_sr_psid_info_same(&new_sr_algo, &old_sr_algo)) {
 			if (buf)
-			snprintf(buf, buf_size, "SR input label");
+				snprintf(
+					buf, buf_size,
+					"SR input label algo-%u (old: %s, new: %s)",
+					i, old_sr_algo.present ? "yes" : "no",
+					new_sr_algo.present ? "yes" : "no");
 			return 0;
 		}
+	}
 
 	if (new->nexthops->count != old->nexthops->count) {
 		if (buf)
@@ -411,7 +503,9 @@ isis_route_create(struct prefix *prefix, struct prefix_ipv6 *src_p,
 				zlog_debug(
 					"ISIS-Rte (%s): route changed: %pFX, change: %s",
 					area->area_tag, prefix, change_buf);
-			rinfo_new->sr_previous = rinfo_old->sr;
+			for (int i = 0; i < SR_ALGORITHM_COUNT; i++)
+				rinfo_new->sr_algo_previous[i] =
+					rinfo_old->sr_algo[i];
 			isis_route_info_delete(rinfo_old);
 			route_info = rinfo_new;
 			UNSET_FLAG(route_info->flag,
@@ -467,11 +561,42 @@ static void isis_route_remove_previous_sid(struct isis_area *area,
 	 * Explicitly uninstall previous Prefix-SID label if it has
 	 * changed or was removed.
 	 */
-	if (route_info->sr_previous.present &&
+	for (int i = 0; i < SR_ALGORITHM_COUNT; i++) {
-	    (!route_info->sr.present ||
+		if (route_info->sr_algo_previous[i].present &&
-	     route_info->sr_previous.label != route_info->sr.label))
+		    (!route_info->sr_algo[i].present ||
-		isis_zebra_prefix_sid_uninstall(area, prefix, route_info,
+		     route_info->sr_algo_previous[i].label !=
-						&route_info->sr_previous);
+			     route_info->sr_algo[i].label))
+			isis_zebra_prefix_sid_uninstall(
+				area, prefix, route_info,
+				&route_info->sr_algo_previous[i]);
+	}
+}
+
+static void set_merge_route_info_sr_algo(struct isis_route_info *mrinfo,
+					 struct isis_route_info *rinfo)
+{
+	for (int i = 0; i < SR_ALGORITHM_COUNT; i++) {
+		if (rinfo->sr_algo[i].present) {
+			assert(i == rinfo->sr_algo[i].algorithm);
+			assert(rinfo->nexthops);
+			assert(rinfo->backup ? rinfo->backup->nexthops != NULL
+					     : true);
+
+			if (mrinfo->sr_algo[i].nexthops != NULL &&
+			    mrinfo->sr_algo[i].nexthops != mrinfo->nexthops) {
+				mrinfo->sr_algo[i].nexthops->del =
+					(void (*)(void *))isis_nexthop_delete;
+				list_delete(&mrinfo->sr_algo[i].nexthops);
+			}
+
+			mrinfo->sr_algo[i] = rinfo->sr_algo[i];
+			mrinfo->sr_algo[i].nexthops = isis_nexthop_list_dup(
+				rinfo->sr_algo[i].nexthops);
+		}
+	}
+
+	UNSET_FLAG(rinfo->flag, ISIS_ROUTE_FLAG_ZEBRA_SYNCED);
+	UNSET_FLAG(mrinfo->flag, ISIS_ROUTE_FLAG_ZEBRA_SYNCED);
 }
 
 static void isis_route_update(struct isis_area *area, struct prefix *prefix,
@@ -490,10 +615,22 @@ static void isis_route_update(struct isis_area *area, struct prefix *prefix,
 		/* Install route. */
 		isis_zebra_route_add_route(area->isis, prefix, src_p,
 					   route_info);
-		/* Install/reinstall Prefix-SID label. */
+
-		if (route_info->sr.present)
+		for (int i = 0; i < SR_ALGORITHM_COUNT; i++) {
+			struct isis_sr_psid_info sr_algo;
+
+			sr_algo = route_info->sr_algo[i];
+
+			/*
+			 * Install/reinstall Prefix-SID label.
+			 */
+			if (sr_algo.present)
 				isis_zebra_prefix_sid_install(area, prefix,
-						      &route_info->sr);
+							      &sr_algo);
+
+			hook_call(isis_route_update_hook, area, prefix,
+				  route_info);
+		}
 
 		hook_call(isis_route_update_hook, area, prefix, route_info);
 
@@ -501,9 +638,12 @@ static void isis_route_update(struct isis_area *area, struct prefix *prefix,
 		UNSET_FLAG(route_info->flag, ISIS_ROUTE_FLAG_ZEBRA_RESYNC);
 	} else {
 		/* Uninstall Prefix-SID label. */
-		if (route_info->sr.present)
+		for (int i = 0; i < SR_ALGORITHM_COUNT; i++)
+			if (route_info->sr_algo[i].present)
 				isis_zebra_prefix_sid_uninstall(
-				area, prefix, route_info, &route_info->sr);
+					area, prefix, route_info,
+					&route_info->sr_algo[i]);
+
 		/* Uninstall route. */
 		isis_zebra_route_del_route(area->isis, prefix, src_p,
 					   route_info);
@@ -523,6 +663,7 @@ static void _isis_route_verify_table(struct isis_area *area,
 #ifdef EXTREME_DEBUG
 	char buff[SRCDEST2STR_BUFFER];
 #endif /* EXTREME_DEBUG */
+	uint8_t algorithm = isis_route_table_algorithm(table);
 
 	for (rnode = route_top(table); rnode;
 	     rnode = srcdest_route_next(rnode)) {
@@ -545,13 +686,14 @@ static void _isis_route_verify_table(struct isis_area *area,
 							 src_p);
 			if (rnode_bck) {
 				rinfo->backup = rnode_bck->info;
-				rinfo->sr.nexthops_backup =
+				rinfo->sr_algo[algorithm].nexthops_backup =
 					rinfo->backup->nexthops;
 				UNSET_FLAG(rinfo->flag,
 					   ISIS_ROUTE_FLAG_ZEBRA_SYNCED);
 			} else if (rinfo->backup) {
 				rinfo->backup = NULL;
-				rinfo->sr.nexthops_backup = NULL;
+				rinfo->sr_algo[algorithm].nexthops_backup =
+					NULL;
 				UNSET_FLAG(rinfo->flag,
 					   ISIS_ROUTE_FLAG_ZEBRA_SYNCED);
 			}
@@ -645,6 +787,8 @@ void isis_route_verify_merge(struct isis_area *area,
 	merge = srcdest_table_init();
 
 	for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
+		uint8_t algorithm =
+			isis_route_table_algorithm(tables[level - 1]);
 		for (rnode = route_top(tables[level - 1]); rnode;
 		     rnode = srcdest_route_next(rnode)) {
 			struct isis_route_info *rinfo = rnode->info;
@@ -665,13 +809,14 @@ void isis_route_verify_merge(struct isis_area *area,
 				tables_backup[level - 1], prefix, src_p);
 			if (rnode_bck) {
 				rinfo->backup = rnode_bck->info;
-				rinfo->sr.nexthops_backup =
+				rinfo->sr_algo[algorithm].nexthops_backup =
 					rinfo->backup->nexthops;
 				UNSET_FLAG(rinfo->flag,
 					   ISIS_ROUTE_FLAG_ZEBRA_SYNCED);
 			} else if (rinfo->backup) {
 				rinfo->backup = NULL;
-				rinfo->sr.nexthops_backup = NULL;
+				rinfo->sr_algo[algorithm].nexthops_backup =
+					NULL;
 				UNSET_FLAG(rinfo->flag,
 					   ISIS_ROUTE_FLAG_ZEBRA_SYNCED);
 			}
@@ -680,6 +825,8 @@ void isis_route_verify_merge(struct isis_area *area,
 			struct isis_route_info *mrinfo = mrnode->info;
 			if (mrinfo) {
 				route_unlock_node(mrnode);
+				set_merge_route_info_sr_algo(mrinfo, rinfo);
+
 				if (CHECK_FLAG(mrinfo->flag,
 					       ISIS_ROUTE_FLAG_ACTIVE)) {
 					/* Clear the ZEBRA_SYNCED flag on the
@@ -723,6 +870,7 @@ void isis_route_invalidate_table(struct isis_area *area,
 {
 	struct route_node *rode;
 	struct isis_route_info *rinfo;
+	uint8_t algorithm = isis_route_table_algorithm(table);
 	for (rode = route_top(table); rode; rode = srcdest_route_next(rode)) {
 		if (rode->info == NULL)
 			continue;
@@ -730,7 +878,7 @@ void isis_route_invalidate_table(struct isis_area *area,
 
 		if (rinfo->backup) {
 			rinfo->backup = NULL;
-			rinfo->sr.nexthops_backup = NULL;
+			rinfo->sr_algo[algorithm].nexthops_backup = NULL;
 			/*
 			 * For now, always force routes that have backup
 			 * nexthops to be reinstalled.

isisd/isis_route.h

@@ -30,12 +30,16 @@ struct isis_route_info {
 	uint8_t flag;
 	uint32_t cost;
 	uint32_t depth;
-	struct isis_sr_psid_info sr;
+	struct isis_sr_psid_info sr_algo[SR_ALGORITHM_COUNT];
-	struct isis_sr_psid_info sr_previous;
+	struct isis_sr_psid_info sr_algo_previous[SR_ALGORITHM_COUNT];
 	struct list *nexthops;
 	struct isis_route_info *backup;
 };
 
+struct isis_route_table_info {
+	uint8_t algorithm;
+};
+
 DECLARE_HOOK(isis_route_update_hook,
 	     (struct isis_area * area, struct prefix *prefix,
 	      struct isis_route_info *route_info),
@@ -73,9 +77,14 @@ void isis_route_invalidate_table(struct isis_area *area,
 void isis_route_node_cleanup(struct route_table *table,
 			     struct route_node *node);
 
+
 void isis_route_switchover_nexthop(struct isis_area *area,
 				   struct route_table *table, int family,
 				   union g_addr *nexthop_addr,
 				   ifindex_t ifindex);
 
+struct isis_route_table_info *isis_route_table_info_alloc(uint8_t algorithm);
+void isis_route_table_info_free(void *info);
+uint8_t isis_route_table_algorithm(const struct route_table *table);
+
 #endif /* _ZEBRA_ISIS_ROUTE_H */

isisd/isis_spf.c

@@ -335,7 +335,9 @@ isis_spftree_new(struct isis_area *area, struct lspdb_head *lspdb,
 	isis_vertex_queue_init(&tree->paths, "IS-IS SPF paths", false);
 	tree->route_table = srcdest_table_init();
 	tree->route_table->cleanup = isis_route_node_cleanup;
+	tree->route_table->info = isis_route_table_info_alloc(algorithm);
 	tree->route_table_backup = srcdest_table_init();
+	tree->route_table_backup->info = isis_route_table_info_alloc(algorithm);
 	tree->route_table_backup->cleanup = isis_route_node_cleanup;
 	tree->area = area;
 	tree->lspdb = lspdb;
@@ -380,6 +382,8 @@ void isis_spftree_del(struct isis_spftree *spftree)
 	list_delete(&spftree->sadj_list);
 	isis_vertex_queue_free(&spftree->tents);
 	isis_vertex_queue_free(&spftree->paths);
+	isis_route_table_info_free(spftree->route_table->info);
+	isis_route_table_info_free(spftree->route_table_backup->info);
 	route_table_finish(spftree->route_table);
 	route_table_finish(spftree->route_table_backup);
 	spftree->route_table = NULL;
@@ -1838,11 +1842,18 @@ void isis_spf_verify_routes(struct isis_area *area, struct isis_spftree **trees)
 
 void isis_spf_invalidate_routes(struct isis_spftree *tree)
 {
+	struct isis_route_table_info *backup_info;
+
 	isis_route_invalidate_table(tree->area, tree->route_table);
 
 	/* Delete backup routes. */
+
+	backup_info = tree->route_table_backup->info;
 	route_table_finish(tree->route_table_backup);
+	isis_route_table_info_free(backup_info);
 	tree->route_table_backup = srcdest_table_init();
+	tree->route_table_backup->info =
+		isis_route_table_info_alloc(tree->algorithm);
 	tree->route_table_backup->cleanup = isis_route_node_cleanup;
 }
 
@@ -2242,8 +2253,10 @@ static void isis_print_route(struct ttable *tt, const struct prefix *prefix,
 			if (nexthop->sr.present) {
 				snprintf(buf_sid, sizeof(buf_sid), "%u",
 					 nexthop->sr.sid.value);
-				sr_op2str(buf_lblop, sizeof(buf_lblop),
+				sr_op2str(
-					  rinfo->sr.label, nexthop->sr.label);
+					buf_lblop, sizeof(buf_lblop),
+					rinfo->sr_algo[SR_ALGORITHM_SPF].label,
+					nexthop->sr.label);
 			} else {
 				strlcpy(buf_sid, "-", sizeof(buf_sid));
 				strlcpy(buf_lblop, "-", sizeof(buf_lblop));
@@ -2298,11 +2311,13 @@ static void isis_print_route(struct ttable *tt, const struct prefix *prefix,
 			char buf_sid[BUFSIZ] = {};
 			char buf_lblop[BUFSIZ] = {};
 
-			if (rinfo->sr.present) {
+			if (rinfo->sr_algo[SR_ALGORITHM_SPF].present) {
 				snprintf(buf_sid, sizeof(buf_sid), "%u",
-					 rinfo->sr.sid.value);
+					 rinfo->sr_algo[SR_ALGORITHM_SPF]
-				sr_op2str(buf_lblop, sizeof(buf_lblop),
+						 .sid.value);
-					  rinfo->sr.label,
+				sr_op2str(
+					buf_lblop, sizeof(buf_lblop),
+					rinfo->sr_algo[SR_ALGORITHM_SPF].label,
 					MPLS_LABEL_IMPLICIT_NULL);
 			} else {
 				strlcpy(buf_sid, "-", sizeof(buf_sid));