openssl/crypto/cmac/cm_ameth.c
Richard Levitte e74bd29053 Prepare EVP_MAC infrastructure for moving all MACs to providers
Quite a few adaptations are needed, most prominently the added code
to allow provider based MACs.

As part of this, all the old information functions are gone, except
for EVP_MAC_name().  Some of them will reappear later, for example
EVP_MAC_do_all() in some form.

MACs by EVP_PKEY was particularly difficult to deal with, as they
need to allocate and deallocate EVP_MAC_CTXs "under the hood", and
thereby implicitly fetch the corresponding EVP_MAC.  This means that
EVP_MACs can't be constant in a EVP_MAC_CTX, as their reference count
may need to be incremented and decremented as part of the allocation
or deallocation of the EVP_MAC_CTX.  It may be that other provider
based EVP operation types may need to be handled in a similar manner.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8877)
2019-08-15 22:12:25 +02:00

53 lines
1.1 KiB
C

/*
* Copyright 2010-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/evp.h>
#include "internal/asn1_int.h"
/*
* CMAC "ASN1" method. This is just here to indicate the maximum CMAC output
* length and to free up a CMAC key.
*/
static int cmac_size(const EVP_PKEY *pkey)
{
return EVP_MAX_BLOCK_LENGTH;
}
static void cmac_key_free(EVP_PKEY *pkey)
{
EVP_MAC_CTX *cmctx = EVP_PKEY_get0(pkey);
EVP_MAC *mac = cmctx == NULL ? NULL : EVP_MAC_CTX_mac(cmctx);
EVP_MAC_CTX_free(cmctx);
EVP_MAC_free(mac);
}
const EVP_PKEY_ASN1_METHOD cmac_asn1_meth = {
EVP_PKEY_CMAC,
EVP_PKEY_CMAC,
0,
"CMAC",
"OpenSSL CMAC method",
0, 0, 0, 0,
0, 0, 0,
cmac_size,
0, 0,
0, 0, 0, 0, 0, 0, 0,
cmac_key_free,
0,
0, 0
};