1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Scalar AES core transform
4  *
5  * Copyright (C) 2017 Linaro Ltd.
6  * Author: Ard Biesheuvel <ard.biesheuvel@linaro.org>
7  */
8 
9 #include <crypto/aes.h>
10 #include <linux/crypto.h>
11 #include <linux/module.h>
12 
13 asmlinkage void __aes_arm_encrypt(u32 *rk, int rounds, const u8 *in, u8 *out);
14 EXPORT_SYMBOL(__aes_arm_encrypt);
15 
16 asmlinkage void __aes_arm_decrypt(u32 *rk, int rounds, const u8 *in, u8 *out);
17 EXPORT_SYMBOL(__aes_arm_decrypt);
18 
19 static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
20 {
21 	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
22 	int rounds = 6 + ctx->key_length / 4;
23 
24 	__aes_arm_encrypt(ctx->key_enc, rounds, in, out);
25 }
26 
27 static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
28 {
29 	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
30 	int rounds = 6 + ctx->key_length / 4;
31 
32 	__aes_arm_decrypt(ctx->key_dec, rounds, in, out);
33 }
34 
35 static struct crypto_alg aes_alg = {
36 	.cra_name			= "aes",
37 	.cra_driver_name		= "aes-arm",
38 	.cra_priority			= 200,
39 	.cra_flags			= CRYPTO_ALG_TYPE_CIPHER,
40 	.cra_blocksize			= AES_BLOCK_SIZE,
41 	.cra_ctxsize			= sizeof(struct crypto_aes_ctx),
42 	.cra_module			= THIS_MODULE,
43 
44 	.cra_cipher.cia_min_keysize	= AES_MIN_KEY_SIZE,
45 	.cra_cipher.cia_max_keysize	= AES_MAX_KEY_SIZE,
46 	.cra_cipher.cia_setkey		= crypto_aes_set_key,
47 	.cra_cipher.cia_encrypt		= aes_encrypt,
48 	.cra_cipher.cia_decrypt		= aes_decrypt,
49 
50 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
51 	.cra_alignmask			= 3,
52 #endif
53 };
54 
55 static int __init aes_init(void)
56 {
57 	return crypto_register_alg(&aes_alg);
58 }
59 
60 static void __exit aes_fini(void)
61 {
62 	crypto_unregister_alg(&aes_alg);
63 }
64 
65 module_init(aes_init);
66 module_exit(aes_fini);
67 
68 MODULE_DESCRIPTION("Scalar AES cipher for ARM");
69 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
70 MODULE_LICENSE("GPL v2");
71 MODULE_ALIAS_CRYPTO("aes");
72