isisd: ignore routes w/ incompatible metric style

Currently the transition metric style is redundant because isis will
always read both reachability TLVs regardless of the configured
metric style. Correct this by only considering TLVs matching our
configuration.

Signed-off-by: Emanuele Di Pascale <emanuele@voltanet.io>

1 files changed, 44 insertions, 33 deletions

diff --git a/isisd/isis_spf.c b/isisd/isis_spf.c
index 57b1d66c2..7e046167f 100644
--- a/isisd/isis_spf.c
+++ b/isisd/isis_spf.c
@@ -820,7 +820,8 @@ lspfragloop:
 #endif /* EXTREME_DEBUG */
 
 	if (no_overload) {
-		if (pseudo_lsp || spftree->mtid == ISIS_MT_IPV4_UNICAST) {
+		if ((pseudo_lsp || spftree->mtid == ISIS_MT_IPV4_UNICAST)
+		    && spftree->area->oldmetric) {
 			struct isis_oldstyle_reach *r;
 			for (r = (struct isis_oldstyle_reach *)
 					 lsp->tlvs->oldstyle_reach.head;
@@ -848,42 +849,47 @@ lspfragloop:
 			}
 		}
 
-		struct isis_item_list *te_neighs = NULL;
-		if (pseudo_lsp || spftree->mtid == ISIS_MT_IPV4_UNICAST)
-			te_neighs = &lsp->tlvs->extended_reach;
-		else
-			te_neighs = isis_lookup_mt_items(&lsp->tlvs->mt_reach,
-							 spftree->mtid);
-
-		struct isis_extended_reach *er;
-		for (er = te_neighs
-				  ? (struct isis_extended_reach *)
-					    te_neighs->head
-				  : NULL;
-		     er; er = er->next) {
-			/* C.2.6 a) */
-			/* Two way connectivity */
-			if (!LSP_PSEUDO_ID(er->id)
-			    && !memcmp(er->id, root_sysid, ISIS_SYS_ID_LEN))
-				continue;
-			if (!pseudo_lsp
-			    && !memcmp(er->id, null_sysid, ISIS_SYS_ID_LEN))
-				continue;
-			dist = cost
-			       + (CHECK_FLAG(spftree->flags,
-					     F_SPFTREE_HOPCOUNT_METRIC)
-					  ? 1
-					  : er->metric);
-			process_N(spftree,
-				  LSP_PSEUDO_ID(er->id) ? VTYPE_PSEUDO_TE_IS
-							: VTYPE_NONPSEUDO_TE_IS,
-				  (void *)er->id, dist, depth + 1, NULL,
-				  parent);
+		if (spftree->area->newmetric) {
+			struct isis_item_list *te_neighs = NULL;
+			if (pseudo_lsp || spftree->mtid == ISIS_MT_IPV4_UNICAST)
+				te_neighs = &lsp->tlvs->extended_reach;
+			else
+				te_neighs = isis_lookup_mt_items(
+					&lsp->tlvs->mt_reach, spftree->mtid);
+
+			struct isis_extended_reach *er;
+			for (er = te_neighs ? (struct isis_extended_reach *)
+						      te_neighs->head
+					    : NULL;
+			     er; er = er->next) {
+				/* C.2.6 a) */
+				/* Two way connectivity */
+				if (!LSP_PSEUDO_ID(er->id)
+				    && !memcmp(er->id, root_sysid,
+					       ISIS_SYS_ID_LEN))
+					continue;
+				if (!pseudo_lsp
+				    && !memcmp(er->id, null_sysid,
+					       ISIS_SYS_ID_LEN))
+					continue;
+				dist = cost
+				       + (CHECK_FLAG(spftree->flags,
+						     F_SPFTREE_HOPCOUNT_METRIC)
+						  ? 1
+						  : er->metric);
+				process_N(spftree,
+					  LSP_PSEUDO_ID(er->id)
+						  ? VTYPE_PSEUDO_TE_IS
+						  : VTYPE_NONPSEUDO_TE_IS,
+					  (void *)er->id, dist, depth + 1, NULL,
+					  parent);
+			}
 		}
 	}
 
 	if (!fabricd && !pseudo_lsp && spftree->family == AF_INET
-	    && spftree->mtid == ISIS_MT_IPV4_UNICAST) {
+	    && spftree->mtid == ISIS_MT_IPV4_UNICAST
+	    && spftree->area->oldmetric) {
 		struct isis_item_list *reachs[] = {
 			&lsp->tlvs->oldstyle_ip_reach,
 			&lsp->tlvs->oldstyle_ip_reach_ext};
@@ -908,6 +914,10 @@ lspfragloop:
 		}
 	}
 
+	/* we can skip all the rest if we're using metric style narrow */
+	if (!spftree->area->newmetric)
+		goto end;
+
 	if (!pseudo_lsp && spftree->family == AF_INET) {
 		struct isis_item_list *ipv4_reachs;
 		if (spftree->mtid == ISIS_MT_IPV4_UNICAST)
@@ -1027,6 +1037,7 @@ lspfragloop:
 		}
 	}
 
+end:
 	if (fragnode == NULL)
 		fragnode = listhead(lsp->lspu.frags);
 	else