Commit | Line | Data |
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8676590a MC |
1 | /** |
2 | * AES routines supporting VMX instructions on the Power 8 | |
3 | * | |
4 | * Copyright (C) 2015 International Business Machines Inc. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; version 2 only. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
18 | * | |
19 | * Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com> | |
20 | */ | |
21 | ||
22 | #include <linux/types.h> | |
23 | #include <linux/err.h> | |
24 | #include <linux/crypto.h> | |
25 | #include <linux/delay.h> | |
26 | #include <linux/hardirq.h> | |
27 | #include <asm/switch_to.h> | |
28 | #include <crypto/aes.h> | |
29 | ||
30 | #include "aesp8-ppc.h" | |
31 | ||
32 | struct p8_aes_ctx { | |
4beb1060 HX |
33 | struct crypto_cipher *fallback; |
34 | struct aes_key enc_key; | |
35 | struct aes_key dec_key; | |
8676590a MC |
36 | }; |
37 | ||
38 | static int p8_aes_init(struct crypto_tfm *tfm) | |
39 | { | |
4beb1060 HX |
40 | const char *alg; |
41 | struct crypto_cipher *fallback; | |
42 | struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); | |
43 | ||
44 | if (!(alg = crypto_tfm_alg_name(tfm))) { | |
45 | printk(KERN_ERR "Failed to get algorithm name.\n"); | |
46 | return -ENOENT; | |
47 | } | |
48 | ||
49 | fallback = crypto_alloc_cipher(alg, 0, CRYPTO_ALG_NEED_FALLBACK); | |
50 | if (IS_ERR(fallback)) { | |
51 | printk(KERN_ERR | |
52 | "Failed to allocate transformation for '%s': %ld\n", | |
53 | alg, PTR_ERR(fallback)); | |
54 | return PTR_ERR(fallback); | |
55 | } | |
56 | printk(KERN_INFO "Using '%s' as fallback implementation.\n", | |
57 | crypto_tfm_alg_driver_name((struct crypto_tfm *) fallback)); | |
58 | ||
59 | crypto_cipher_set_flags(fallback, | |
60 | crypto_cipher_get_flags((struct | |
61 | crypto_cipher *) | |
62 | tfm)); | |
63 | ctx->fallback = fallback; | |
64 | ||
65 | return 0; | |
8676590a MC |
66 | } |
67 | ||
68 | static void p8_aes_exit(struct crypto_tfm *tfm) | |
69 | { | |
4beb1060 | 70 | struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); |
8676590a | 71 | |
4beb1060 HX |
72 | if (ctx->fallback) { |
73 | crypto_free_cipher(ctx->fallback); | |
74 | ctx->fallback = NULL; | |
75 | } | |
8676590a MC |
76 | } |
77 | ||
78 | static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key, | |
4beb1060 | 79 | unsigned int keylen) |
8676590a | 80 | { |
4beb1060 HX |
81 | int ret; |
82 | struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); | |
83 | ||
44d21c3f | 84 | preempt_disable(); |
4beb1060 | 85 | pagefault_disable(); |
2d6f0600 | 86 | enable_kernel_vsx(); |
4beb1060 HX |
87 | ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); |
88 | ret += aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key); | |
dc4fbba1 | 89 | disable_kernel_vsx(); |
4beb1060 | 90 | pagefault_enable(); |
44d21c3f | 91 | preempt_enable(); |
4beb1060 HX |
92 | |
93 | ret += crypto_cipher_setkey(ctx->fallback, key, keylen); | |
94 | return ret; | |
8676590a MC |
95 | } |
96 | ||
97 | static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) | |
98 | { | |
4beb1060 HX |
99 | struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); |
100 | ||
101 | if (in_interrupt()) { | |
102 | crypto_cipher_encrypt_one(ctx->fallback, dst, src); | |
103 | } else { | |
44d21c3f | 104 | preempt_disable(); |
4beb1060 | 105 | pagefault_disable(); |
2d6f0600 | 106 | enable_kernel_vsx(); |
4beb1060 | 107 | aes_p8_encrypt(src, dst, &ctx->enc_key); |
dc4fbba1 | 108 | disable_kernel_vsx(); |
4beb1060 | 109 | pagefault_enable(); |
44d21c3f | 110 | preempt_enable(); |
4beb1060 | 111 | } |
8676590a MC |
112 | } |
113 | ||
114 | static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) | |
115 | { | |
4beb1060 HX |
116 | struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); |
117 | ||
118 | if (in_interrupt()) { | |
119 | crypto_cipher_decrypt_one(ctx->fallback, dst, src); | |
120 | } else { | |
44d21c3f | 121 | preempt_disable(); |
4beb1060 | 122 | pagefault_disable(); |
2d6f0600 | 123 | enable_kernel_vsx(); |
4beb1060 | 124 | aes_p8_decrypt(src, dst, &ctx->dec_key); |
dc4fbba1 | 125 | disable_kernel_vsx(); |
4beb1060 | 126 | pagefault_enable(); |
44d21c3f | 127 | preempt_enable(); |
4beb1060 | 128 | } |
8676590a MC |
129 | } |
130 | ||
131 | struct crypto_alg p8_aes_alg = { | |
4beb1060 HX |
132 | .cra_name = "aes", |
133 | .cra_driver_name = "p8_aes", | |
134 | .cra_module = THIS_MODULE, | |
135 | .cra_priority = 1000, | |
136 | .cra_type = NULL, | |
137 | .cra_flags = CRYPTO_ALG_TYPE_CIPHER | CRYPTO_ALG_NEED_FALLBACK, | |
138 | .cra_alignmask = 0, | |
139 | .cra_blocksize = AES_BLOCK_SIZE, | |
140 | .cra_ctxsize = sizeof(struct p8_aes_ctx), | |
141 | .cra_init = p8_aes_init, | |
142 | .cra_exit = p8_aes_exit, | |
143 | .cra_cipher = { | |
144 | .cia_min_keysize = AES_MIN_KEY_SIZE, | |
145 | .cia_max_keysize = AES_MAX_KEY_SIZE, | |
146 | .cia_setkey = p8_aes_setkey, | |
147 | .cia_encrypt = p8_aes_encrypt, | |
148 | .cia_decrypt = p8_aes_decrypt, | |
149 | }, | |
8676590a | 150 | }; |