RFR: 8207775: Better management of CipherCore buffers

[Seán Coffey]

Thanks again for review Tony. I think you raise a good point and should 
give some performance gain.

for line 676: maybe this :

                  byte[] copy = Arrays.copyOf(output, len);
                  if (decrypting) {
                      Arrays.fill(output, (byte) 0x00);
                  }
                  return copy;


perhaps the same again for around line 852 :
                  byte[] copy = Arrays.copyOf(output, len);
                  if (decrypting) {
                      Arrays.fill(output, (byte) 0x00);
                  }
                  return copy;

==

Any other reviews/comments from folks before I submit final build/test & 
webrev ?

Regards,
Sean.

On 01/08/18 15:55, Anthony Scarpino wrote:
>
>
> My only comment is if it makes sense to have the change at 676 to also 
> only null out on decrypt?
>
> Otherwise I'm fine with the changes
>
> Tony
>
> On 07/31/2018 02:04 AM, Seán Coffey wrote:
>> Thanks for review Tony. Comments inline..
>>
>> On 27/07/18 21:02, Anthony Scarpino wrote:
>>> If we are going to add more, here are two more ton consider:
>>>
>>> - It looks like there is another Arrays.copyOf() on doFinal() line 851
>> Good point.
>>> - doFinal()
>>> at line 897 there might be something that should be done with 
>>> 'buffer'.  In particular as a result of line 963's arraycopy().
>> Yes - I've identified two areas where we can be proactive about 
>> nulling out 'buffer' contents. That's around the same time where we 
>> reset 'buffered' to 0. See lines 777 and 967
>>
>> http://cr.openjdk.java.net/~coffeys/webrev.8207775.v3/webrev/
>>
>> regards,
>> Sean.
>>>
>>> Tony
>>>
>>>
>>> On 07/27/2018 08:29 AM, Seán Coffey wrote:
>>>> Thanks Tony. If it's alright with you, I'd like to make one more 
>>>> edit for this change.
>>>>
>>>> http://cr.openjdk.java.net/~coffeys/webrev.8207775.v2/webrev/
>>>>
>>>> There's a condition where we can null out an array early if we're 
>>>> returning a copy. See lines 671-683
>>>>
>>>> Regards,
>>>> Sean.
>>>>
>>>> On 26/07/18 17:42, Anthony Scarpino wrote:
>>>>> On 07/26/2018 07:36 AM, Seán Coffey wrote:
>>>>>> https://bugs.openjdk.java.net/browse/JDK-8207775
>>>>>>
>>>>>> Simple enough fix to null out some internal buffers once they're 
>>>>>> no longer required.
>>>>>>
>>>>>> webrev : http://cr.openjdk.java.net/~coffeys/webrev.8207775/webrev/
>>>>>>
>>>>>> regards,
>>>>>> Sean.
>>>>>>
>>>>>
>>>>> that looks fine..
>>>>>
>>>>> Tony
>>>>
>>>
>>
>