tipc: obtain node identity from interface by default

Selecting and explicitly configuring a TIPC node identity may be
unwanted in some cases.

In this commit we introduce a default setting if the identity has not
been set at the moment the first bearer is enabled. We do this by
using a raw copy of a unique identifier from the used interface: MAC
address in the case of an L2 bearer, IPv4/IPv6 address in the case
of a UDP bearer.

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, 13 insertions, 0 deletions

diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index 3deabcab4882..2c13b18426d9 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -47,6 +47,8 @@
 #include <net/addrconf.h>
 #include <linux/tipc_netlink.h>
 #include "core.h"
+#include "addr.h"
+#include "net.h"
 #include "bearer.h"
 #include "netlink.h"
 #include "msg.h"
@@ -647,6 +649,7 @@ static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
 	struct udp_port_cfg udp_conf = {0};
 	struct udp_tunnel_sock_cfg tuncfg = {NULL};
 	struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
+	u8 node_id[NODE_ID_LEN] = {0,};
 
 	ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
 	if (!ub)
@@ -677,6 +680,16 @@ static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
 	if (err)
 		goto err;
 
+	/* Autoconfigure own node identity if needed */
+	if (!tipc_own_id(net)) {
+		memcpy(node_id, local.ipv6.in6_u.u6_addr8, 16);
+		tipc_net_init(net, node_id, 0);
+	}
+	if (!tipc_own_id(net)) {
+		pr_warn("Failed to set node id, please configure manually\n");
+		return -EINVAL;
+	}
+
 	b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
 	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
 	rcu_assign_pointer(b->media_ptr, ub);