isisd: update struct sr_prefix_cfg with algorithm id

The information in prefix-sid has a new property
called algorithm id.  This is used to identify
the algorithm that separates it in the same IGP
network. This is used in Flex-Algo.In all other
cases, the algorithm id is basically 0.

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

isisd/isis_lsp.c

@@ -907,7 +907,8 @@ static void lsp_build_ext_reach_ipv4(struct isis_lsp *lsp,
 			struct sr_prefix_cfg *pcfg = NULL;
 
 			if (area->srdb.enabled)
-				pcfg = isis_sr_cfg_prefix_find(area, ipv4);
+				pcfg = isis_sr_cfg_prefix_find(
+					area, ipv4, SR_ALGORITHM_SPF);
 
 			isis_tlvs_add_extended_ip_reach(lsp->tlvs, ipv4, metric,
 							true, pcfg);
@@ -941,7 +942,8 @@ static void lsp_build_ext_reach_ipv6(struct isis_lsp *lsp,
 			struct sr_prefix_cfg *pcfg = NULL;
 
 			if (area->srdb.enabled)
-				pcfg = isis_sr_cfg_prefix_find(area, p);
+				pcfg = isis_sr_cfg_prefix_find(
+					area, p, SR_ALGORITHM_SPF);
 
 			isis_tlvs_add_ipv6_reach(lsp->tlvs,
 						 isis_area_ipv6_topology(area),
@@ -1205,7 +1207,8 @@ static void lsp_build(struct isis_lsp *lsp, struct isis_area *area)
 
 					if (area->srdb.enabled)
 						pcfg = isis_sr_cfg_prefix_find(
-							area, ipv4);
+							area, ipv4,
+							SR_ALGORITHM_SPF);
 
 					isis_tlvs_add_extended_ip_reach(
 						lsp->tlvs, ipv4, metric, false,
@@ -1228,7 +1231,7 @@ static void lsp_build(struct isis_lsp *lsp, struct isis_area *area)
 
 				if (area->srdb.enabled)
 					pcfg = isis_sr_cfg_prefix_find(area,
-								       ipv6);
+								       ipv6, 0);
 
 				isis_tlvs_add_ipv6_reach(
 					lsp->tlvs,

isisd/isis_nb_config.c

@@ -2276,7 +2276,7 @@ int isis_instance_segment_routing_prefix_sid_map_prefix_sid_create(
 	area = nb_running_get_entry(args->dnode, NULL, true);
 	yang_dnode_get_prefix(&prefix, args->dnode, "./prefix");
 
-	pcfg = isis_sr_cfg_prefix_add(area, &prefix);
+	pcfg = isis_sr_cfg_prefix_add(area, &prefix, SR_ALGORITHM_SPF);
 	nb_running_set_entry(args->dnode, pcfg);
 
 	return NB_OK;

isisd/isis_sr.c

@@ -57,7 +57,17 @@ static void sr_adj_sid_del(struct sr_adjacency *sra);
 static inline int sr_prefix_sid_cfg_compare(const struct sr_prefix_cfg *a,
 					    const struct sr_prefix_cfg *b)
 {
-	return prefix_cmp(&a->prefix, &b->prefix);
+	int ret;
+
+	ret = prefix_cmp(&a->prefix, &b->prefix);
+	if (ret != 0)
+		return ret;
+
+	ret = a->algorithm - b->algorithm;
+	if (ret != 0)
+		return ret;
+
+	return 0;
 }
 DECLARE_RBTREE_UNIQ(srdb_prefix_cfg, struct sr_prefix_cfg, entry,
 		    sr_prefix_sid_cfg_compare);
@@ -331,7 +341,8 @@ int isis_sr_cfg_srlb_update(struct isis_area *area, uint32_t lower_bound,
  * @return	  Newly added Prefix-SID configuration structure
  */
 struct sr_prefix_cfg *isis_sr_cfg_prefix_add(struct isis_area *area,
-					     const struct prefix *prefix)
+					     const struct prefix *prefix,
+					     uint8_t algorithm)
 {
 	struct sr_prefix_cfg *pcfg;
 	struct interface *ifp;
@@ -341,6 +352,7 @@ struct sr_prefix_cfg *isis_sr_cfg_prefix_add(struct isis_area *area,
 	pcfg = XCALLOC(MTYPE_ISIS_SR_INFO, sizeof(*pcfg));
 	pcfg->prefix = *prefix;
 	pcfg->area = area;
+	pcfg->algorithm = algorithm;
 
 	/* Pull defaults from the YANG module. */
 	pcfg->sid_type = yang_get_default_enum(
@@ -386,11 +398,13 @@ void isis_sr_cfg_prefix_del(struct sr_prefix_cfg *pcfg)
  * @return	  Configured Prefix-SID structure if found, NULL otherwise
  */
 struct sr_prefix_cfg *isis_sr_cfg_prefix_find(struct isis_area *area,
-					      union prefixconstptr prefix)
+					      union prefixconstptr prefix,
+					      uint8_t algorithm)
 {
 	struct sr_prefix_cfg pcfg = {};
 
 	prefix_copy(&pcfg.prefix, prefix.p);
+	pcfg.algorithm = algorithm;
 	return srdb_prefix_cfg_find(&area->srdb.config.prefix_sids, &pcfg);
 }
 
@@ -405,7 +419,7 @@ void isis_sr_prefix_cfg2subtlv(const struct sr_prefix_cfg *pcfg, bool external,
 			       struct isis_prefix_sid *psid)
 {
 	/* Set SID algorithm. */
-	psid->algorithm = SR_ALGORITHM_SPF;
+	psid->algorithm = pcfg->algorithm;
 
 	/* Set SID flags. */
 	psid->flags = 0;
@@ -939,7 +953,8 @@ static int sr_if_new_hook(struct interface *ifp)
 	FOR_ALL_INTERFACES_ADDRESSES (ifp, connected, node) {
 		struct sr_prefix_cfg *pcfg;
 
-		pcfg = isis_sr_cfg_prefix_find(area, connected->address);
+		pcfg = isis_sr_cfg_prefix_find(area, connected->address,
+					       SR_ALGORITHM_SPF);
 		if (!pcfg)
 			continue;
 

isisd/isis_sr.h

@@ -147,6 +147,9 @@ struct sr_prefix_cfg {
 
 	/* Backpointer to IS-IS area. */
 	struct isis_area *area;
+
+	/* SR Algorithm number */
+	uint8_t algorithm;
 };
 
 /* Per-area IS-IS Segment Routing Data Base (SRDB). */
@@ -198,11 +201,13 @@ extern int isis_sr_cfg_srgb_update(struct isis_area *area, uint32_t lower_bound,
 				   uint32_t upper_bound);
 extern int isis_sr_cfg_srlb_update(struct isis_area *area, uint32_t lower_bound,
 				   uint32_t upper_bound);
-extern struct sr_prefix_cfg *
+extern struct sr_prefix_cfg *isis_sr_cfg_prefix_add(struct isis_area *area,
-isis_sr_cfg_prefix_add(struct isis_area *area, const struct prefix *prefix);
+						    const struct prefix *prefix,
+						    uint8_t algorithm);
 extern void isis_sr_cfg_prefix_del(struct sr_prefix_cfg *pcfg);
 extern struct sr_prefix_cfg *
-isis_sr_cfg_prefix_find(struct isis_area *area, union prefixconstptr prefix);
+isis_sr_cfg_prefix_find(struct isis_area *area, union prefixconstptr prefix,
+			uint8_t algorithm);
 extern void isis_sr_prefix_cfg2subtlv(const struct sr_prefix_cfg *pcfg,
 				      bool external,
 				      struct isis_prefix_sid *psid);