river-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Gregg Wonderly <gr...@wonderly.org>
Subject Re: PAM - Pluggable Authentication Modules Any Ideas?
Date Thu, 13 May 2010 21:40:52 GMT
Craig L Russell wrote:
> Hi Gregg,
> 
> On May 13, 2010, at 8:23 AM, Gregg Wonderly wrote:
>> If you use System.load(), then you can use a static initialization 
>> block to copy the jni bits from the jar into a temp directory and then 
>> load it from that path.
> 
> My understanding is that you need to start the VM with the knowledge of 
> where all the jni libraries are. You can either put them into the 
> "standard" place (varies by platform) or in a special place and name 
> that special directory using the -Djava.library.path system property 
> when you start the VM. It doesn't work to set the system property after 
> you start the VM.

System.loadLibrary() does behave this way.  System.load() does not, and can load 
from anywhere providing permissions are granted appropriately.

Gregg Wonderly

>> Associated permissions need to be granted of course.
> 
> Of course.
> 
> Craig
> 
>> Gregg Wonderly
>>
>> Sent from my iPad
>>
>> On May 13, 2010, at 9:59 AM, Dennis Reedy <dennis.reedy@gmail.com> wrote:
>>
>>>
>>> On May 12, 2010, at 714PM, Peter Firmstone wrote:
>>>
>>>> I like the sound of that.
>>>>
>>>> We can have an Authentication Service, we could place the constraint 
>>>> of a key signature on that particular service (don't want untrusted 
>>>> parties providing authentication), but once loaded, the smart proxy 
>>>> could contain the JNI code required to perform the authentication?
>>>
>>> I'm not really sure if (and how) a smart proxy that once download can 
>>> (or should be given permission to) load a native library. From what I 
>>> have seen, the native library needs to be loaded from a location that 
>>> the JVM knows about (a priori). Would that native library need to be 
>>> installed onto the machine to the location where the JVM has been 
>>> configured to load native libraries from before that native library 
>>> was loaded?
>>>
>>> Would the native library need to be loaded by a class loader that is 
>>> hierarchically a parent of class loaders that load services? This is 
>>> because the same JNI native library cannot be loaded into more than 
>>> one class loader, but different child class loaders of a class loader 
>>> that loaded the JNI library can gain access to the loaded library 
>>> such that System.loadLibrary will succeed (this naturally assumes 
>>> that other class loaders in the JVM would want the capability to load 
>>> the native library).
>>>
>>> Dennis
>>>
>>>
> 
> Craig L Russell
> Architect, Oracle
> http://db.apache.org/jdo
> 408 276-5638 mailto:Craig.Russell@oracle.com
> P.S. A good JDO? O, Gasp!
> 
> 


Mime
View raw message