tipc: introduce constants for tipc address validation

In this commit, we introduce defines for tipc address size,
offset and mask specification for Zone.Cluster.Node.
There is no functional change in this commit.

Reviewed-by: Jon Maloy <[e-mail]>
Signed-off-by: Parthasarathy Bhuvaragan <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/uapi/linux/tipc.h

···
 	__u32 upper;
 };
 
+/* TIPC Address Size, Offset, Mask specification for Z.C.N
+ */
+#define TIPC_NODE_BITS          12
+#define TIPC_CLUSTER_BITS       12
+#define TIPC_ZONE_BITS          8
+
+#define TIPC_NODE_OFFSET        0
+#define TIPC_CLUSTER_OFFSET     TIPC_NODE_BITS
+#define TIPC_ZONE_OFFSET        (TIPC_CLUSTER_OFFSET + TIPC_CLUSTER_BITS)
+
+#define TIPC_NODE_SIZE          ((1UL << TIPC_NODE_BITS) - 1)
+#define TIPC_CLUSTER_SIZE       ((1UL << TIPC_CLUSTER_BITS) - 1)
+#define TIPC_ZONE_SIZE          ((1UL << TIPC_ZONE_BITS) - 1)
+
+#define TIPC_NODE_MASK		(TIPC_NODE_SIZE << TIPC_NODE_OFFSET)
+#define TIPC_CLUSTER_MASK	(TIPC_CLUSTER_SIZE << TIPC_CLUSTER_OFFSET)
+#define TIPC_ZONE_MASK		(TIPC_ZONE_SIZE << TIPC_ZONE_OFFSET)
+
+#define TIPC_ZONE_CLUSTER_MASK (TIPC_ZONE_MASK | TIPC_CLUSTER_MASK)
+
 static inline __u32 tipc_addr(unsigned int zone,
 			      unsigned int cluster,
 			      unsigned int node)
 {
-	return (zone << 24) | (cluster << 12) | node;
+	return (zone << TIPC_ZONE_OFFSET) |
+		(cluster << TIPC_CLUSTER_OFFSET) |
+		node;
 }
 
 static inline unsigned int tipc_zone(__u32 addr)
 {
-	return addr >> 24;
+	return addr >> TIPC_ZONE_OFFSET;
 }
 
 static inline unsigned int tipc_cluster(__u32 addr)
 {
-	return (addr >> 12) & 0xfff;
+	return (addr & TIPC_CLUSTER_MASK) >> TIPC_CLUSTER_OFFSET;
 }
 
 static inline unsigned int tipc_node(__u32 addr)
 {
-	return addr & 0xfff;
+	return addr & TIPC_NODE_MASK;
 }
 
 /*

net/tipc/addr.h

···
 #include <net/netns/generic.h>
 #include "core.h"
 
-#define TIPC_ZONE_MASK		0xff000000u
-#define TIPC_CLUSTER_MASK	0xfffff000u
-
 static inline u32 tipc_own_addr(struct net *net)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
···
 
 static inline u32 tipc_cluster_mask(u32 addr)
 {
-	return addr & TIPC_CLUSTER_MASK;
+	return addr & TIPC_ZONE_CLUSTER_MASK;
 }
 
 u32 tipc_own_addr(struct net *net);

net/tipc/bearer.c

···
 	if (tipc_addr_domain_valid(disc_domain) &&
 	    (disc_domain != tn->own_addr)) {
 		if (tipc_in_scope(disc_domain, tn->own_addr)) {
-			disc_domain = tn->own_addr & TIPC_CLUSTER_MASK;
+			disc_domain = tn->own_addr & TIPC_ZONE_CLUSTER_MASK;
 			res = 0;   /* accept any node in own cluster */
 		} else if (in_own_cluster_exact(net, disc_domain))
 			res = 0;   /* accept specified node in own cluster */
···
 	u32 prio;
 
 	prio = TIPC_MEDIA_LINK_PRI;
-	domain = tn->own_addr & TIPC_CLUSTER_MASK;
+	domain = tn->own_addr & TIPC_ZONE_CLUSTER_MASK;
 
 	if (!info->attrs[TIPC_NLA_BEARER])
 		return -EINVAL;