tipc: Add routines for safe checking of node's network address

Introduces routines that test whether a given network address is
equal to a node's own network address or if it lies within the node's
own network cluster, and which work properly regardless of whether
the node is using the default network address <0.0.0> or a non-zero
network address that is assigned later on. In essence, these routines
ensure that address <0.0.0> is treated as an alias for "this node",
regardless of which network address the node is actually using.

Old users of the pre-existing more strict match in_own_cluster()
have been accordingly redirected to what is now called
in_own_cluster_exact() --- which does not extend matching to <0,0,0>.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

net/tipc/addr.h

@@ -50,11 +50,29 @@ static inline u32 tipc_cluster_mask(u32 addr)
 	return addr & TIPC_CLUSTER_MASK;
 }
 
-static inline int in_own_cluster(u32 addr)
+static inline int in_own_cluster_exact(u32 addr)
 {
 	return !((addr ^ tipc_own_addr) >> 12);
 }
 
+/**
+ * in_own_node - test for node inclusion; <0.0.0> always matches
+ */
+
+static inline int in_own_node(u32 addr)
+{
+	return (addr == tipc_own_addr) || !addr;
+}
+
+/**
+ * in_own_cluster - test for cluster inclusion; <0.0.0> always matches
+ */
+
+static inline int in_own_cluster(u32 addr)
+{
+	return in_own_cluster_exact(addr) || !addr;
+}
+
 /**
  * addr_domain - convert 2-bit scope value to equivalent message lookup domain
  *

net/tipc/bearer.c

@@ -449,7 +449,7 @@ int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
 		if (tipc_in_scope(disc_domain, tipc_own_addr)) {
 			disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
 			res = 0;   /* accept any node in own cluster */
-		} else if (in_own_cluster(disc_domain))
+		} else if (in_own_cluster_exact(disc_domain))
 			res = 0;   /* accept specified node in own cluster */
 	}
 	if (res) {

net/tipc/name_table.c

@@ -342,7 +342,7 @@ static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
 	list_add(&publ->zone_list, &info->zone_list);
 	info->zone_list_size++;
 
-	if (in_own_cluster(node)) {
+	if (in_own_cluster_exact(node)) {
 		list_add(&publ->cluster_list, &info->cluster_list);
 		info->cluster_list_size++;
 	}
@@ -411,7 +411,7 @@ found:
 
 	/* Remove publication from cluster scope list, if present */
 
-	if (in_own_cluster(node)) {
+	if (in_own_cluster_exact(node)) {
 		list_del(&publ->cluster_list);
 		info->cluster_list_size--;
 	}
@@ -604,7 +604,7 @@ u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
 		publ = list_first_entry(&info->node_list, struct publication,
 					node_list);
 		list_move_tail(&publ->node_list, &info->node_list);
-	} else if (in_own_cluster(*destnode)) {
+	} else if (in_own_cluster_exact(*destnode)) {
 		if (list_empty(&info->cluster_list))
 			goto no_match;
 		publ = list_first_entry(&info->cluster_list, struct publication,

net/tipc/node.c

@@ -72,7 +72,7 @@ struct tipc_node *tipc_node_find(u32 addr)
 	struct tipc_node *node;
 	struct hlist_node *pos;
 
-	if (unlikely(!in_own_cluster(addr)))
+	if (unlikely(!in_own_cluster_exact(addr)))
 		return NULL;
 
 	hlist_for_each_entry(node, pos, &node_htable[tipc_hashfn(addr)], hash) {