Add basic EVP_KEYMGMT API and libcrypto <-> provider interface

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)

1 files changed, 1 insertions, 0 deletions

diff --git a/util/private.num b/util/private.num
index f63319dd96..3307e3e239 100644
--- a/util/private.num
+++ b/util/private.num
@@ -24,6 +24,7 @@ CRYPTO_EX_new                           datatype
 DTLS_timer_cb                           datatype
 EVP_KDF                                 datatype
 EVP_KDF_CTX                             datatype
+EVP_KEYMGMT                             datatype
 EVP_MAC                                 datatype
 EVP_MAC_CTX                             datatype
 EVP_PKEY_gen_cb                         datatype