make NetworkInterface working under XP

on >= Vista NetworkInterface works, but if you try under XP you have ifIndex always not setted: if you compile with XP SP1 defines you get code working on >=XP

Net/src/NetworkInterface.cpp

@@ -1097,12 +1097,22 @@ NetworkInterface::Map NetworkInterface::map(bool ipOnly, bool upOnly)
 		ifIndex = pAddress->Ipv6IfIndex;
 	#elif (_WIN32_WINNT >= 0x0501) && (NTDDI_VERSION >= 0x05010100) // Win XP SP1
 		#if defined (IP_ADAPTER_IPV6_ENABLED) // Vista
-			if ((pAddress->Flags & IP_ADAPTER_IPV6_ENABLED) &&
+			if(osvi.dwMajorVersion>=6)//vista
-				(osvi.dwMajorVersion >= 5) &&
-				(osvi.dwMinorVersion >= 1) &&
-				(osvi.dwBuildNumber >=1))
 			{
-				ifIndex = pAddress->Ipv6IfIndex;
+				if ((pAddress->Flags & IP_ADAPTER_IPV6_ENABLED) &&
+					(osvi.dwMajorVersion >= 5) &&
+					(osvi.dwMinorVersion >= 1) &&
+					(osvi.dwBuildNumber >=1))
+				{
+					ifIndex = pAddress->Ipv6IfIndex;
+				}
+			}
+			else if ((osvi.dwMajorVersion >= 5) &&
+					(osvi.dwMinorVersion >= 1) &&
+					(osvi.dwBuildNumber >= 1))
+				{
+					ifIndex = pAddress->Ipv6IfIndex;
+				}
 			}
 		#else // !defined(IP_ADAPTER_IPV6_ENABLED)
 			if ((osvi.dwMajorVersion >= 5) &&
@@ -1116,7 +1126,14 @@ NetworkInterface::Map NetworkInterface::map(bool ipOnly, bool upOnly)
 #endif // POCO_HAVE_IPv6
 
 #if defined (IP_ADAPTER_IPV4_ENABLED)
-		if (pAddress->Flags & IP_ADAPTER_IPV4_ENABLED)
+		if(osvi.dwMajorVersion>=6)
+		{//vista
+			if (pAddress->Flags & IP_ADAPTER_IPV4_ENABLED)
+			{
+				ifIndex = pAddress->IfIndex;
+			}
+		}
+		else
 		{
 			ifIndex = pAddress->IfIndex;
 		}
@@ -1205,8 +1222,15 @@ NetworkInterface::Map NetworkInterface::map(bool ipOnly, bool upOnly)
 #elif (_WIN32_WINNT >= 0x0501) && (NTDDI_VERSION >= 0x05010100) // Win XP SP1
 						ULONG prefixLength = 0;
 	#if (_WIN32_WINNT >= 0x0600) // Vista and newer
-						prefixLength = pUniAddr->OnLinkPrefixLength;
+						if (osvi.dwMajorVersion >= 6)
-						broadcastAddress = getBroadcastAddress(pAddress->FirstPrefix, address);
+						{
+							prefixLength = pUniAddr->OnLinkPrefixLength;
+							broadcastAddress = getBroadcastAddress(pAddress->FirstPrefix, address);
+						}
+						else
+						{
+							broadcastAddress = getBroadcastAddress(pAddress->FirstPrefix, address, &prefixLength);
+						}
 	#else
 						broadcastAddress = getBroadcastAddress(pAddress->FirstPrefix, address, &prefixLength);
 	#endif