Help with assertion encryption ?

[Cantor, Scott]

On 5/20/14, 8:52 PM, "Brent Putman" <putmanb at georgetown.edu> wrote:

>
>Looking at this further and comparing to some AES GCM test code that I
>had from a long time ago, I think the problem may be the IV size that
>Santuario uses for the GCM variants, as defined in their JCEMapper.
>They specify 96 bits (12 bytes). (Non-GCM AES uses 128 bits).  My test
>code with BC was using 128 bits (16 bytes).  I tried 96 bits and it
>still worked.  So maybe it's really supposed to be 128, but BC pads it
>out or something if it's less.
>
>When I get into the office, I'll test where I have a Java 8 environment,
>but I suspect it will show that Java 8's AES GCM support requires an IV
>of 128 bits.  I don't know off-hand what the correct IV size(s) for AES
>GCM are, have to go do some reading.  Maybe Scott or Ian knows.

I'll have to review. There's no guarantee that the C++ implementation is
correct, I had very little to go on and not much help since the Java
version didn't have it. It was one of the harder things I've built.

But since this is failing in the Java code, this isn't (yet) an interop
issue with the SP, so we'll cross our fingers.

I'll try and download specs and code before I board tomorrow so I can
review on the plane.

-- Scott