Re: Cryptlib OpenPGP enveloping occasionally produces unreadable data

>>I notice that when we perform openpgp enveloping, cryptlib occasionally
>>produces data that cannot be de-enveloped by itself. I've attached the code
>>for a test I wrote for this. When I run it, cryptlib gives
>>CRYPT_ERROR_BADDATA about 5-10 times out of a 1000.

> The problem occurs because some of the lower-level code used by cryptlib
> performs leading-zero truncation and some doesn't (specifically, PKCS #11
> drivers are erratic as to whether they do it or not, see the code comment in
> device/pkcs11_pkc.c).  cryptlib tries to compensate for the differences, but
> in this case it over-compensated (the fact that about one in 256 operations
> failed was the giveaway because 1/256 results will have a leading zero, what
> puzzled me was that I knew I'd addressed this issue, but it was being
> cancelled out in a second location that only occurred with PGP data).  Anyway,
> the fix is, in mechs/mech_pkwrap.c, line 297, to change the code block to:

At least the internet did not collapse with this one ;)

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