// SPDX-License-Identifier: GPL-2.0

#include <asm/neon.h>
#include <asm/simd.h>
#include <crypto/algapi.h>
#include <crypto/sm4.h>
#include <crypto/internal/simd.h>
#include <linux/module.h>
#include <linux/cpufeature.h>
#include <linux/types.h>

MODULE_ALIAS_CRYPTO("sm4");
MODULE_ALIAS_CRYPTO("sm4-ce");
MODULE_DESCRIPTION("SM4 symmetric cipher using ARMv8 Crypto Extensions");
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
MODULE_LICENSE("GPL v2");

asmlinkage void sm4_ce_do_crypt(const u32 *rk, void *out, const void *in);

static int sm4_ce_setkey(struct crypto_tfm *tfm, const u8 *key,
                       unsigned int key_len)
{
        struct sm4_ctx *ctx = crypto_tfm_ctx(tfm);

        return sm4_expandkey(ctx, key, key_len);
}

static void sm4_ce_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
        const struct sm4_ctx *ctx = crypto_tfm_ctx(tfm);

        if (!crypto_simd_usable()) {
                sm4_crypt_block(ctx->rkey_enc, out, in);
        } else {
                scoped_ksimd()
                        sm4_ce_do_crypt(ctx->rkey_enc, out, in);
        }
}

static void sm4_ce_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
        const struct sm4_ctx *ctx = crypto_tfm_ctx(tfm);

        if (!crypto_simd_usable()) {
                sm4_crypt_block(ctx->rkey_dec, out, in);
        } else {
                scoped_ksimd()
                        sm4_ce_do_crypt(ctx->rkey_dec, out, in);
        }
}

static struct crypto_alg sm4_ce_alg = {
        .cra_name                       = "sm4",
        .cra_driver_name                = "sm4-ce",
        .cra_priority                   = 300,
        .cra_flags                      = CRYPTO_ALG_TYPE_CIPHER,
        .cra_blocksize                  = SM4_BLOCK_SIZE,
        .cra_ctxsize                    = sizeof(struct sm4_ctx),
        .cra_module                     = THIS_MODULE,
        .cra_u.cipher = {
                .cia_min_keysize        = SM4_KEY_SIZE,
                .cia_max_keysize        = SM4_KEY_SIZE,
                .cia_setkey             = sm4_ce_setkey,
                .cia_encrypt            = sm4_ce_encrypt,
                .cia_decrypt            = sm4_ce_decrypt
        }
};

static int __init sm4_ce_mod_init(void)
{
        return crypto_register_alg(&sm4_ce_alg);
}

static void __exit sm4_ce_mod_fini(void)
{
        crypto_unregister_alg(&sm4_ce_alg);
}

module_cpu_feature_match(SM4, sm4_ce_mod_init);
module_exit(sm4_ce_mod_fini);