CID-1116485: cast cidr during bit shifting

 and simple test included

Author: DaanHoogland

utils/src/main/java/com/cloud/utils/net/NetUtils.java

@@ -775,7 +775,7 @@ public static String getSubNet(final String ip, final String netmask) {
     }
 
     public static String getCidrSubNet(final String ip, final long cidrSize) {
-        final long numericNetmask = 0xffffffff >> MAX_CIDR - cidrSize << MAX_CIDR - cidrSize;
+        final long numericNetmask = ((long)0xffffffff) >> MAX_CIDR - cidrSize << MAX_CIDR - cidrSize;
         final String netmask = NetUtils.long2Ip(numericNetmask);
         return getSubNet(ip, netmask);
     }

utils/src/test/java/com/cloud/utils/net/NetUtilsTest.java

@@ -418,4 +418,10 @@ public void testIs31PrefixCidr() {
 
         assertTrue("It should pass! 31 bit prefix.", is31PrefixCidr);
     }
+    @Test
+    public void testGetCidrSubNet() {
+        final String cidr = "10.10.0.0/16";
+        String subnet = NetUtils.getCidrSubNet("10.10.10.10", 16);
+        assertTrue(NetUtils.isIpWithtInCidrRange(subnet, cidr));
+    }
 }