jmx-dev RFR: 8010285 Enforce the requirement of Management Interfaces being public

[Daniel Fuchs]

On 5/29/13 7:17 PM, Jaroslav Bachorik wrote:
> On Wed 29 May 2013 05:33:21 PM CEST, Eamonn McManus wrote:
>> I would recommend against changing the code to do additional calls to
>> Class.forName during MBean introspection. As I recall we made the
>> opposite change some years ago, both because Class.forName can be slow
>> (it may call out to a user ClassLoader) and because it is a potential
>> source of security problems.
>
> Thanks. I was trying to dig some history from mercurial but couldn't.
> Walking through all the related interfaces is equally acceptable - I've
> tried both of the solutions and they test well with the regtests.
>
> I am still puzzled by the current implementation which will fail to
> locate the correct MBean interface in eg.
>
> <<CInterface>> extends <<BInterface>> extends <<ServiceMBean>>
>
> ClassA extends Service implements <<CInterface>>
>
> as the process would stop on <<BInterface>> (checks the superclass of
> the ClassA, checks all the interfaces implemented by the Service class,
> checks all the interfaces extended by <<CInterface>>) which plainly
> does not conform to the MBean interface naming convention and would
> miss the <<ServiceMBean>> interface.

Hi Jaroslav,

<<Service>> would have to implement <<ServiceMBean>> either
directly or indirectly.

So the current implementation is correct.

If <<ServiceMBean>> is not assignable from <<Service>> then
<<ServiceMBean>> is not an MBean interface for ClassA.

You can work around that by wrapping an instance of ClassA
in an instance of  javax.management.StandardMBean, and by
specifying <<ServiceMBean>>.class as the MBean interface
in the constructor.

Hope this helps,

-- daniel

>
> -JB-
>
>>
>> Éamonn
>>
>>
>> 2013/5/29 Jaroslav Bachorik <jaroslav.bachorik at oracle.com
>> <mailto:jaroslav.bachorik at oracle.com>>
>>
>>      Updated webrev -
>>      http://cr.openjdk.java.net/~jbachorik/8010285/webrev.01
>>
>>      It adds regtests and takes care of the comments from David and
>>      Shanliang.
>>
>>      -JB-
>>
>>      On 05/28/2013 04:22 PM, Jaroslav Bachorik wrote:
>>      > The fix enforces the management interfaces (read MBean and MXBean
>>      > interfaces) being public. While this is defined in the
>>      specification it
>>      > was not enforced in any way and it was allowed to create MBeans
>>      for eg.
>>      > private MBean interfaces.
>>      >
>>      > The fix adds checks when creating and registering MBeans and throws
>>      > javax.management.NotCompliantMBeanException when a user tries to
>>      create
>>      > an MBean with non-public management interface.
>>      >
>>      > Since this change can cause problems for users having non-public
>>      > management interfaces a system property is introduced that will
>>      revert
>>      > to the old behaviour when set (com.sun.jmx.mbeans.allowNonPublic).
>>      >
>>      > Thanks,
>>      >
>>      > -JB-
>>      >
>>
>>
>
>