[openssl-users] OCSP_BASICRESP_verify() in 1.1.0

[Matt Caswell]

On 31/10/17 13:06, Dave Coombs wrote:
> Hello,
> 
> I was fiddling around with OpenSSL 1.1.0 this past weekend, because
> One Day We'll Need To Upgrade (tm), and ran into the following.
> 
> We have some code that uses OCSP_BASICRESP_verify() with 1.0.1 /
> 1.0.2 to confirm that the signature on an ocsp response is correct.
> This is a macro in ocsp.h, which directly accesses the signature,
> signatureAlgorithm, and tbsResponseData members of the OCSP_BASICRESP
> structure.  In 1.1.0, this structure is now opaque, but the macros
> are still present in the public ocsp.h, so any external code that
> uses this macro can't compile.
> 
> I can get around this by copying the struct definitions from
> ocsp_lcl.h into the external code, but that both defeats the purpose
> of opaque structures and will cause me problems if the structure
> contents ever change.
> 
> Is the correct solution to use OCSP_basic_verify(), which feels like
> overkill for my needs (the code in question is *part of* our own
> path-validation routine), or might there be some other way?

Can you use OCSP_basic_verify() passing in OCSP_NOVERIFY in the final
"flags" argument? This basically finds the signer certificate and
verifies the signature using OCSP_BASICRESP_verify(), but skips all the
chain validation bit.

> Either way, I hereby report you've got a few macros in a public
> header that can't possibly work as things stand. :-)

Yes - a bug. I'm tempted just to remove them.

Matt