tipc: remove restrictions on node address values

Nominally, TIPC organizes network nodes into a three-level network
hierarchy consisting of the levels 'zone', 'cluster' and 'node'. This
hierarchy is reflected in the node address format, - it is sub-divided
into an 8-bit zone id, and 12 bit cluster id, and a 12-bit node id.

However, the 'zone' and 'cluster' levels have in reality never been
fully implemented,and never will be. The result of this has been
that the first 20 bits the node identity structure have been wasted,
and the usable node identity range within a cluster has been limited
to 12 bits. This is starting to become a problem.

In the following commits, we will need to be able to connect between
nodes which are using the whole 32-bit value space of the node address.
We therefore remove the restrictions on which values can be assigned
to node identity, -it is from now on only a 32-bit integer with no
assumed internal structure.

Isolation between clusters is now achieved only by setting different
values for the 'network id' field used during neighbor discovery, in
practice leading to the latter becoming the new cluster identity.

The rules for accepting discovery requests/responses from neighboring
nodes now become:

- If the user is using legacy address format on both peers, reception
  of discovery messages is subject to the legacy lookup domain check
  in addition to the cluster id check.

- Otherwise, the discovery request/response is always accepted, provided
  both peers have the same network id.

This secures backwards compatibility for users who have been using zone
or cluster identities as cluster separators, instead of the intended
'network id'.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/tipc/net.c b/net/tipc/net.c
index 5c4c4405b78e..a074f285e6ea 100644
--- a/net/tipc/net.c
+++ b/net/tipc/net.c
@@ -121,7 +121,7 @@ int tipc_net_start(struct net *net, u32 addr)
 			     TIPC_CLUSTER_SCOPE, 0, tn->own_addr);
 
 	pr_info("Started in network mode\n");
-	pr_info("Own node address %s, network identity %u\n",
+	pr_info("Own node address %s, cluster identity %u\n",
 		tipc_addr_string_fill(addr_string, tn->own_addr),
 		tn->net_id);
 	return 0;
@@ -238,7 +238,7 @@ int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info)
 			return -EPERM;
 
 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
-		if (!tipc_addr_node_valid(addr))
+		if (!addr)
 			return -EINVAL;
 
 		tipc_net_start(net, addr);