Oh, one other thing in case you weren't talking about this in the
context of Cipher and instead were talking about the AlgorithmParameters
object itself. If that's all you've got in scope one approach is to
call getParameterSpec(IvParameterSpec.class).getIV(); That will give
you the byte array as well. Now that I think about it, I should
probably do that in my test code because I went and manually parsed the
DER encoding. :) Glad you brought it up.
--Jamil
On 12/7/2020 5:39 PM, Jamil Nimeh wrote:
Hi Bernd, it's not a stupid question at all. I think what you might
be looking for is Cipher.getIV()? In the case of ChaCha20-Poly1305,
that method returns the nonce as a byte array where getParameters()
returns an AlgorithmParameters object where the encoding is consistent
with RFC 8103.
But both getParameters() and getIV() were doing the wrong thing
(chucking NPE) when they should've either come up with a random param
or null, respectively when in a pre-initialized state.
--Jamil
On 12/7/2020 5:19 PM, Bernd Eckenfels wrote:
BTW stupid - somewhat related - question, why does the nonce to be
parsed out of a DER blob, shouldn’t there be an getter on the
Parameter Spec object? Many protocols would need the raw array, is
there a matching spec - or should we add one?
Gruss
Bernd
--
http://bernd.eckenfels.net
------------------------------------------------------------------------
*Von:* security-dev <security-dev-r...@openjdk.java.net> im Auftrag
von Jamil Nimeh <jni...@openjdk.java.net>
*Gesendet:* Monday, December 7, 2020 9:05:16 PM
*An:* security-dev@openjdk.java.net <security-dev@openjdk.java.net>
*Betreff:* Re: RFR: 8257769: Cipher.getParameters() throws NPE for
ChaCha20-Poly1305 [v2]
On Mon, 7 Dec 2020 19:53:27 GMT, Valerie Peng <valer...@openjdk.org>
wrote:
>> Jamil Nimeh has updated the pull request incrementally with one
additional commit since the last revision:
>>
>> pre-init getParameters nonce data is now a local variable
>
>
src/java.base/share/classes/com/sun/crypto/provider/ChaCha20Cipher.java
line 232:
>
>> 230: // this call should cause a random nonce to be
generated, but
>> 231: // not attached to the object.
>> 232: byte[] nonceData = initialized ? nonce :
createRandomNonce(null);
>
> The "initialized" variable is set to false in engineDoFinal() call.
So, if users call getParameters() after finish cipher operation, this
will return random nonces instead of the one used in previous doFinal
operation. Will this be a little un-intuitive?
Unintuitive is a charitable way to put it. After doFinal the Cipher
technically isn't in an uninitialized state per the spec, it's
supposed to be in the state it would be immediately following
init(). So the wrong behavior would happen in this use case. Will fix.
-------------
PR: https://git.openjdk.java.net/jdk/pull/1644
<https://git.openjdk.java.net/jdk/pull/1644>
