[mdnsd] Ignore RTM_NEWLINK event generated by wext.

mDNSResponder refreshes all the interface list whenever it receives
RTM_NEWLINK event from kernel. It is found that Wireless events are
carried through rtnetlink socket to user space. They are encapsulated in
the IFLA_WIRELESS field of a RTM_NEWLINK message. There is no need to
refresh all the interface list on receiving these Wireless events
containing IFLA_WIRELESS field.
This patch ignores any Wireless event which contains IFLA_WIRELESS
field.

Change-Id: Ic0361cb229fb282d7f0c5f5d2cb5b0da8e01543f
Signed-off-by: Saurav Babu <saurav.babu@samsung.com>

diff --git a/mDNSPosix/mDNSPosix.c b/mDNSPosix/mDNSPosix.c
index 39cd66c..fa4da21 100755 (executable)
--- a/mDNSPosix/mDNSPosix.c
+++ b/mDNSPosix/mDNSPosix.c
@@ -1067,6 +1067,29 @@ mDNSlocal void      PrintNetLinkMsg(const struct nlmsghdr *pNLMsg)
 }
 #endif
 
+#if defined TIZEN_EXT
+static int extract_link(struct ifinfomsg *msg, int bytes, const char **ifname, unsigned char *operstate)
+{
+        struct rtattr *attr;
+
+        for (attr = IFLA_RTA(msg); RTA_OK(attr, bytes); attr = RTA_NEXT(attr, bytes)) {
+                switch (attr->rta_type) {
+                case IFLA_IFNAME:
+                        *ifname = RTA_DATA(attr);
+                        break;
+                case IFLA_OPERSTATE:
+                        *operstate = *((unsigned char *) RTA_DATA(attr));
+                        break;
+                case IFLA_WIRELESS:
+                        /* Ignore RTM_NEWLINK with IFLA_WIRELESS */
+                        return 0;
+                }
+        }
+
+        return 1;
+}
+#endif
+
 mDNSlocal mDNSu32       ProcessRoutingNotification(int sd)
 // Read through the messages on sd and if any indicate that any interface records should
 // be torn down and rebuilt, return affected indices as a bitmask. Otherwise return 0.
@@ -1075,6 +1098,10 @@ mDNSlocal mDNSu32       ProcessRoutingNotification(int sd)
     char buff[4096];
     struct nlmsghdr         *pNLMsg = (struct nlmsghdr*) buff;
     mDNSu32 result = 0;
+#if defined TIZEN_EXT
+    unsigned char operstate = 0xff;
+    const char *ifname = NULL;
+#endif
 
     // The structure here is more complex than it really ought to be because,
     // unfortunately, there's no good way to size a buffer in advance large
@@ -1108,6 +1135,19 @@ mDNSlocal mDNSu32       ProcessRoutingNotification(int sd)
         PrintNetLinkMsg(pNLMsg);
 #endif
 
+#if defined TIZEN_EXT
+        if (pNLMsg->nlmsg_type == RTM_NEWLINK) {
+            struct ifinfomsg *msg = (struct ifinfomsg *) NLMSG_DATA(pNLMsg);
+
+            /* Check if RTM_NEWLINK contains IFLA_WIRELESS */
+            if (extract_link(msg, IFA_PAYLOAD(pNLMsg), &ifname, &operstate) == 0)
+                return result;
+#if MDNS_DEBUGMSGS
+            printf("Interface Name %s Operstate %d\n", ifname, operstate);
+#endif
+        }
+#endif
+
         // Process the NetLink message
         if (pNLMsg->nlmsg_type == RTM_GETLINK || pNLMsg->nlmsg_type == RTM_NEWLINK)
             result |= 1 << ((struct ifinfomsg*) NLMSG_DATA(pNLMsg))->ifi_index;