/* Copyright (c) (2011,2012,2014,2015,2019) Apple Inc. All rights reserved.
 *
 * corecrypto is licensed under Apple Inc.’s Internal Use License Agreement (which
 * is contained in the License.txt file distributed with corecrypto) and only to 
 * people who accept that license. IMPORTANT:  Any license rights granted to you by 
 * Apple Inc. (if any) are limited to internal use within your organization only on 
 * devices and computers you own or control, for the sole purpose of verifying the 
 * security characteristics and correct functioning of the Apple Software.  You may 
 * not, directly or indirectly, redistribute the Apple Software or any portions thereof.
 */

#include <corecrypto/ccpad.h>
#include <corecrypto/cc_priv.h>
#include <stdbool.h>

size_t ccpad_pkcs7_ecb_decrypt(const struct ccmode_ecb *ecb, ccecb_ctx *ecb_key,
                               size_t nbytes, const void *in, void *out) {
    const size_t block_size = ecb->block_size;
    size_t nblocks = nbytes / block_size;
    size_t pad_size = 0;
    // Decryption
    ecb->ecb(ecb_key, nblocks, in, out);
    unsigned char *plain = out;
    // Padding parsing and determining real size.
    pad_size = ccpad_pkcs7_decode(block_size,plain+((nblocks-1)*block_size));
    return nbytes - pad_size;
}
