iftable: fix incomplete list of interfaces via nlif_query

RTM_GETLINK with NLM_F_DUMP returns a multi-part netlink message.
The existing code only handled the first message of it, thus,
ignoring the remaining interfaces.

This is the cause of the following bug in conntrackd:

[Thu Aug  9 14:14:23 2012] (pid=3819) [notice] -- starting in daemon mode --
[Thu Aug  9 14:14:23 2012] (pid=3819) [ERROR] no dedicated links available!
[Thu Aug  9 14:14:23 2012] (pid=3819) [ERROR] no dedicated links available!
[Thu Aug  9 14:14:23 2012] (pid=3819) [ERROR] no dedicated links available!
[Thu Aug  9 14:19:54 2012] (pid=3819) [notice] ---- shutdown received ----

Thanks to Jan Engelhardt for providing useful pointer to address the
problem.

Reported-by: Arturo Borrero <aborrero@cica.es>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/src/rtnl.c b/src/rtnl.c
index 1092c81..5ccb272 100644
--- a/src/rtnl.c
+++ b/src/rtnl.c
@@ -193,6 +193,15 @@ int rtnl_receive(struct rtnl_handle *rtnl_handle)
 	return 1;
 }
 
+int rtnl_receive_multi(struct rtnl_handle *rtnl_handle)
+{
+	while (1) {
+		if (rtnl_receive(rtnl_handle) <= 0)
+			break;
+	}
+	return 1;
+}
+
 /* rtnl_open - constructor of rtnetlink module */
 struct rtnl_handle *rtnl_open(void)
 {