/*
 * Copyright (c) 2015 South Silicon Valley Microelectronics Inc.
 * Copyright (c) 2015 iComm Corporation
 *
 * This program is free software: you can redistribute it and/or modify 
 * it under the terms of the GNU General Public License as published by 
 * the Free Software Foundation, either version 3 of the License, or 
 * (at your option) any later version.
 * This program is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of 
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  
 * See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License 
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/module.h>
#include <linux/crypto.h>
#include <crypto/aes.h>
#define AES_MAXNR 14
typedef struct {
 unsigned int rd_key[4 *(AES_MAXNR + 1)];
 int rounds;
} AES_KEY;
struct AES_CTX {
 AES_KEY enc_key;
 AES_KEY dec_key;
};
asmlinkage void AES_encrypt(const u8 *in, u8 *out, AES_KEY *ctx);
asmlinkage void AES_decrypt(const u8 *in, u8 *out, AES_KEY *ctx);
asmlinkage int private_AES_set_decrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key);
asmlinkage int private_AES_set_encrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key);
static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
 struct AES_CTX *ctx = crypto_tfm_ctx(tfm);
 AES_encrypt(src, dst, &ctx->enc_key);
}
static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
 struct AES_CTX *ctx = crypto_tfm_ctx(tfm);
 AES_decrypt(src, dst, &ctx->dec_key);
}
static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
  unsigned int key_len)
{
 struct AES_CTX *ctx = crypto_tfm_ctx(tfm);
 switch (key_len) {
 case AES_KEYSIZE_128:
  key_len = 128;
  break;
 case AES_KEYSIZE_192:
  key_len = 192;
  break;
 case AES_KEYSIZE_256:
  key_len = 256;
  break;
 default:
  tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
  return -EINVAL;
 }
 if (private_AES_set_encrypt_key(in_key, key_len, &ctx->enc_key) == -1) {
  tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
  return -EINVAL;
 }
 ctx->dec_key = ctx->enc_key;
 if (private_AES_set_decrypt_key(in_key, key_len, &ctx->dec_key) == -1) {
  tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
  return -EINVAL;
 }
 return 0;
}
static struct crypto_alg aes_alg = {
 .cra_name = "aes",
 .cra_driver_name = "aes-asm",
 .cra_priority = 200,
 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
 .cra_blocksize = AES_BLOCK_SIZE,
 .cra_ctxsize = sizeof(struct AES_CTX),
 .cra_module = THIS_MODULE,
 .cra_list = LIST_HEAD_INIT(aes_alg.cra_list),
 .cra_u = {
  .cipher = {
   .cia_min_keysize = AES_MIN_KEY_SIZE,
   .cia_max_keysize = AES_MAX_KEY_SIZE,
   .cia_setkey = aes_set_key,
   .cia_encrypt = aes_encrypt,
   .cia_decrypt = aes_decrypt
  }
 }
};
int aes_init(void)
{
 return crypto_register_alg(&aes_alg);
}
void aes_fini(void)
{
 crypto_unregister_alg(&aes_alg);
}