What version of the PKCS#1 spec is gcrypt implemented against?

Question

I am trying to determine which version of the PKCS#1 spec that gcrypt is implemented against.

Thank you

Answer 1

The gcrypt manual talks about "type 1 padding" (for signatures) and "type 2 padding" (for encryption). This means that it implements the "old-style" PKCS#1 signature and encryption methods, also called "v1.5" because they were the only ones specified in PKCS#1 v1.5. gcrypt does not appear (from what I see in the documentation) to implement the more recent OAEP (encryption) and PSS (signature) paddings.

Note, though, that the "v1.5" paddings are still specified in more recent versions of PKCS#1, so it can be said that gcrypt is also implemented against PKCS#1 v2.1 -- but it does not implement all of it.