The idea with the key management "operation" is to support the
following set of functionality:
- Key domain parameter generation
- Key domain parameter import
- Key domain parameter export
- Key generation
- Key import
- Key export
- Key loading (HSM / hidden key support)
With that set of function, we can support handling domain parameters
on one provider, key handling on another, and key usage on a third,
with transparent export / import of applicable data. Of course, if a
provider doesn't offer export / import functionality, then all
operations surrounding a key must be performed with the same
provider.
This method also avoids having to do anything special with legacy
assignment of libcrypto key structures, i.e. EVP_PKEY_assign_RSA().
They will simply be used as keys to be exported from whenever they are
used with provider based operations.
This change only adds the EVP_KEYMGMT API and the libcrypto <->
provider interface. Further changes will integrate them into existing
libcrypto functionality.
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9312)