David McCullough | f0be44f | 2012-09-07 04:17:02 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Glue Code for the asm optimized version of the AES Cipher Algorithm |
| 3 | */ |
| 4 | |
| 5 | #include <linux/module.h> |
| 6 | #include <linux/crypto.h> |
| 7 | #include <crypto/aes.h> |
| 8 | |
| 9 | #define AES_MAXNR 14 |
| 10 | |
| 11 | typedef struct { |
| 12 | unsigned int rd_key[4 *(AES_MAXNR + 1)]; |
| 13 | int rounds; |
| 14 | } AES_KEY; |
| 15 | |
| 16 | struct AES_CTX { |
| 17 | AES_KEY enc_key; |
| 18 | AES_KEY dec_key; |
| 19 | }; |
| 20 | |
| 21 | asmlinkage void AES_encrypt(const u8 *in, u8 *out, AES_KEY *ctx); |
| 22 | asmlinkage void AES_decrypt(const u8 *in, u8 *out, AES_KEY *ctx); |
| 23 | asmlinkage int private_AES_set_decrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key); |
| 24 | asmlinkage int private_AES_set_encrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key); |
| 25 | |
| 26 | static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) |
| 27 | { |
| 28 | struct AES_CTX *ctx = crypto_tfm_ctx(tfm); |
| 29 | AES_encrypt(src, dst, &ctx->enc_key); |
| 30 | } |
| 31 | |
| 32 | static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) |
| 33 | { |
| 34 | struct AES_CTX *ctx = crypto_tfm_ctx(tfm); |
| 35 | AES_decrypt(src, dst, &ctx->dec_key); |
| 36 | } |
| 37 | |
| 38 | static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, |
| 39 | unsigned int key_len) |
| 40 | { |
| 41 | struct AES_CTX *ctx = crypto_tfm_ctx(tfm); |
| 42 | |
| 43 | switch (key_len) { |
| 44 | case AES_KEYSIZE_128: |
| 45 | key_len = 128; |
| 46 | break; |
| 47 | case AES_KEYSIZE_192: |
| 48 | key_len = 192; |
| 49 | break; |
| 50 | case AES_KEYSIZE_256: |
| 51 | key_len = 256; |
| 52 | break; |
| 53 | default: |
| 54 | tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; |
| 55 | return -EINVAL; |
| 56 | } |
| 57 | |
| 58 | if (private_AES_set_encrypt_key(in_key, key_len, &ctx->enc_key) == -1) { |
| 59 | tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; |
| 60 | return -EINVAL; |
| 61 | } |
| 62 | /* private_AES_set_decrypt_key expects an encryption key as input */ |
| 63 | ctx->dec_key = ctx->enc_key; |
| 64 | if (private_AES_set_decrypt_key(in_key, key_len, &ctx->dec_key) == -1) { |
| 65 | tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; |
| 66 | return -EINVAL; |
| 67 | } |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | static struct crypto_alg aes_alg = { |
| 72 | .cra_name = "aes", |
| 73 | .cra_driver_name = "aes-asm", |
| 74 | .cra_priority = 200, |
| 75 | .cra_flags = CRYPTO_ALG_TYPE_CIPHER, |
| 76 | .cra_blocksize = AES_BLOCK_SIZE, |
| 77 | .cra_ctxsize = sizeof(struct AES_CTX), |
| 78 | .cra_module = THIS_MODULE, |
| 79 | .cra_list = LIST_HEAD_INIT(aes_alg.cra_list), |
| 80 | .cra_u = { |
| 81 | .cipher = { |
| 82 | .cia_min_keysize = AES_MIN_KEY_SIZE, |
| 83 | .cia_max_keysize = AES_MAX_KEY_SIZE, |
| 84 | .cia_setkey = aes_set_key, |
| 85 | .cia_encrypt = aes_encrypt, |
| 86 | .cia_decrypt = aes_decrypt |
| 87 | } |
| 88 | } |
| 89 | }; |
| 90 | |
| 91 | static int __init aes_init(void) |
| 92 | { |
| 93 | return crypto_register_alg(&aes_alg); |
| 94 | } |
| 95 | |
| 96 | static void __exit aes_fini(void) |
| 97 | { |
| 98 | crypto_unregister_alg(&aes_alg); |
| 99 | } |
| 100 | |
| 101 | module_init(aes_init); |
| 102 | module_exit(aes_fini); |
| 103 | |
| 104 | MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm (ASM)"); |
| 105 | MODULE_LICENSE("GPL"); |
| 106 | MODULE_ALIAS("aes"); |
| 107 | MODULE_ALIAS("aes-asm"); |
| 108 | MODULE_AUTHOR("David McCullough <ucdevel@gmail.com>"); |