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