[cgutman] 66734: [IP] - Don't select disconnected interfaces as default - Only count prefix matches of non-zero length - Fixes connectivity with multiple NICs when one or more is disconnected

Author: cgutman
Date: Mon Mar 16 00:52:02 2015
New Revision: 66734

URL: http://svn.reactos.org/svn/reactos?rev=66734&view=rev
Log:
[IP]
- Don't select disconnected interfaces as default
- Only count prefix matches of non-zero length
- Fixes connectivity with multiple NICs when one or more is disconnected

Modified:
    trunk/reactos/lib/drivers/ip/network/interface.c

Modified: trunk/reactos/lib/drivers/ip/network/interface.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/lib/drivers/ip/network/inte...
==============================================================================
--- trunk/reactos/lib/drivers/ip/network/interface.c	[iso-8859-1] (original)
+++ trunk/reactos/lib/drivers/ip/network/interface.c	[iso-8859-1] Mon Mar 16 00:52:02 2015
@@ -134,6 +134,11 @@
         A2S(Address), A2S(Prefix)));
 #endif

+    /* Don't report matches for empty prefixes */
+    if (Length == 0) {
+        return FALSE;
+    }
+
     /* Check that initial integral bytes match */
     while (Length > 8) {
         if (*pAddress++ != *pPrefix++)
@@ -152,37 +157,48 @@
 {
    KIRQL OldIrql;
    ULONG Index = 0;
+   ULONG IfStatus;

IF_LIST_ITER(CurrentIF);

TcpipAcquireSpinLock(&InterfaceListLock, &OldIrql);
    /* DHCP hack: Always return the adapter without an IP address */
    ForEachInterface(CurrentIF) {
-      if (CurrentIF->Context) {
-          if (AddrIsUnspecified(&CurrentIF->Unicast)) {
-              TcpipReleaseSpinLock(&InterfaceListLock, OldIrql);
+      if (CurrentIF->Context && AddrIsUnspecified(&CurrentIF->Unicast)) {
+          TcpipReleaseSpinLock(&InterfaceListLock, OldIrql);
+          if (NT_SUCCESS(GetInterfaceConnectionStatus(CurrentIF, &IfStatus)) &&
+                (IfStatus == MIB_IF_OPER_STATUS_OPERATIONAL)) {
               return CurrentIF;
           }
+          TcpipAcquireSpinLock(&InterfaceListLock, &OldIrql);
       }
    } EndFor(CurrentIF);

/* Try to continue from the next adapter */
    ForEachInterface(CurrentIF) {
-      if (CurrentIF->Context) {
-          if (Index++ == NextDefaultAdapter) {
+      if (CurrentIF->Context && (Index++ == NextDefaultAdapter)) {
+          TcpipReleaseSpinLock(&InterfaceListLock, OldIrql);
+          if (NT_SUCCESS(GetInterfaceConnectionStatus(CurrentIF, &IfStatus)) &&
+                (IfStatus == MIB_IF_OPER_STATUS_OPERATIONAL)) {
               NextDefaultAdapter++;
-              TcpipReleaseSpinLock(&InterfaceListLock, OldIrql);
               return CurrentIF;
           }
+          TcpipAcquireSpinLock(&InterfaceListLock, &OldIrql);
       }
    } EndFor(CurrentIF);

/* No luck, so we'll choose the first adapter this time */
+   Index = 0;
    ForEachInterface(CurrentIF) {
       if (CurrentIF->Context) {
-          NextDefaultAdapter = 1;
+          Index++;
           TcpipReleaseSpinLock(&InterfaceListLock, OldIrql);
-          return CurrentIF;
+          if (NT_SUCCESS(GetInterfaceConnectionStatus(CurrentIF, &IfStatus)) &&
+                (IfStatus == MIB_IF_OPER_STATUS_OPERATIONAL)) {
+              NextDefaultAdapter = Index;
+              return CurrentIF;
+          }
+          TcpipAcquireSpinLock(&InterfaceListLock, &OldIrql);
       }
    } EndFor(CurrentIF);