/* SPDX-License-Identifier: GPL-2.0 */

/*
 * Common values for the SM4 algorithm
 * Copyright (C) 2018 ARM Limited or its affiliates.
 * Copyright (c) 2021 Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
 */

#ifndef _CRYPTO_SM4_H
#define _CRYPTO_SM4_H

#include <linux/types.h>
#include <linux/crypto.h>

#define SM4_KEY_SIZE    16
#define SM4_BLOCK_SIZE  16
#define SM4_RKEY_WORDS  32

struct sm4_ctx {
        u32 rkey_enc[SM4_RKEY_WORDS];
        u32 rkey_dec[SM4_RKEY_WORDS];
};

extern const u32 crypto_sm4_fk[];
extern const u32 crypto_sm4_ck[];
extern const u8 crypto_sm4_sbox[];

/**
 * sm4_expandkey - Expands the SM4 key as described in GB/T 32907-2016
 * @ctx:        The location where the computed key will be stored.
 * @in_key:     The supplied key.
 * @key_len:    The length of the supplied key.
 *
 * Returns 0 on success. The function fails only if an invalid key size (or
 * pointer) is supplied.
 */
int sm4_expandkey(struct sm4_ctx *ctx, const u8 *in_key,
                          unsigned int key_len);

/**
 * sm4_crypt_block - Encrypt or decrypt a single SM4 block
 * @rk:         The rkey_enc for encrypt or rkey_dec for decrypt
 * @out:        Buffer to store output data
 * @in:         Buffer containing the input data
 */
void sm4_crypt_block(const u32 *rk, u8 *out, const u8 *in);

#endif