Re: Decrypting openpgp data created by gpg

Hi Peter,

Another small issue that I found related to PGP:

I need to use nested enveloping to encrypt a compressed envelope (and set
the CRYPT_ENVINFO_CONTENTTYPE attribute of the encrypting envelope to
CRYPT_CONTENT_COMPRESSEDDATA in the process). However when I decrypt such
an encrypted envelope (which contains compressed data), the content type I
get back from the envelope is CRYPT_CONTENT_DATA instead of
CRYPT_CONTENT_COMPRESSEDDATA. Again, this works properly when the envelope
type is set to CRYPT_FORMAT_CRYPTLIB.

I think this is a problem in the enveloping step (as opposed to the
de-enveloping step), as I have successfully de-enveloped PGP messages with
the same structure that were created by a different program (for example,
when solving the original problem I had).

Thanks,
Lahiru


On Wed, Feb 27, 2013 at 2:28 PM, Lahiru Dissanayake <[email protected]>wrote:

> Hi Peter,
>
> Found another issue similar to this when specifying the
> CRYPT_ENVINFO_SIGNATURE attribute to verify a digitally signed PGP
> envelope. The following line returns -2 in the de-enveloping process:
>
> status = cryptSetAttribute(cryptEnvelope, CRYPT_ENVINFO_SIGNATURE,
> publicKeyContext);
>
> You don't get this error when the envelope type is CRYPT_FORMAT_CRYPTLIB.
> Similar to the issue with the private key context, directly specifying a
> keyset instead of the above line works.
>
> I'd appreciate it if you could provide a simple workaround as before,
> rather than having to wait for the next release.
>
> Thanks,
> Lahiru
>
>
> On Mon, Feb 25, 2013 at 10:47 AM, Peter Gutmann <[email protected]
> > wrote:
>
>> Lahiru Dissanayake <[email protected]> writes:
>>
>> >Are you sure this works? Because the line
>> >{ CRYPT_ENVINFO_PRIVATEKEY,     formatAll,              ACTION_CRYPT,
>> MESSAGE_CHECK_PKC_DECRYPT, 0 },
>> >fixed the error, but the new one
>> >{ CRYPT_ENVINFO_PRIVATEKEY,     formatAllDeenv, ACTION_CRYPT,
>> MESSAGE_CHECK_PKC_DECRYPT, ENVELOPE_ISDEENVELOPE },
>> >brought it back.
>>
>> Ah, you also need to change formatAllDeenv to:
>>
>> static const CRYPT_FORMAT_TYPE formatAllDeenv[] = {
>>         CRYPT_FORMAT_AUTO, CRYPT_FORMAT_CMS, CRYPT_FORMAT_PGP,
>>         CRYPT_FORMAT_NONE, CRYPT_FORMAT_NONE };
>>
>> but then there are changes elsewhere as well... for now just leave it at
>> formatAll and it should work, the next release will contain the full set
>> of
>> changes.
>>
>> Peter.
>>
>
>

_______________________________________________
Cryptlib mailing list
[email protected] via Mail: [email protected]
Archive: ftp://ftp.franken.de/pub/crypt/cryptlib/archives/
http://news.gmane.org/gmane.comp.encryption.cryptlib
Posts from non-subscribed addresses are blocked to prevent spam, please
subscribe in order to post messages.