blob: 022c7ab7351a08c4f6afdff324e0b51eb1214bb1 [file] [log] [blame]
Marcelo H. Cerri86765902015-02-06 14:57:22 -02001/**
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
32struct p8_aes_ctx {
Herbert Xu4beb1062015-06-15 16:55:46 +080033 struct crypto_cipher *fallback;
34 struct aes_key enc_key;
35 struct aes_key dec_key;
Marcelo H. Cerri86765902015-02-06 14:57:22 -020036};
37
38static int p8_aes_init(struct crypto_tfm *tfm)
39{
Herbert Xu4beb1062015-06-15 16:55:46 +080040 const char *alg;
41 struct crypto_cipher *fallback;
42 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerri86765902015-02-06 14:57:22 -020043
Herbert Xu4beb1062015-06-15 16:55:46 +080044 if (!(alg = crypto_tfm_alg_name(tfm))) {
45 printk(KERN_ERR "Failed to get algorithm name.\n");
46 return -ENOENT;
47 }
Marcelo H. Cerri86765902015-02-06 14:57:22 -020048
Herbert Xu4beb1062015-06-15 16:55:46 +080049 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));
Marcelo H. Cerri86765902015-02-06 14:57:22 -020058
Herbert Xu4beb1062015-06-15 16:55:46 +080059 crypto_cipher_set_flags(fallback,
60 crypto_cipher_get_flags((struct
61 crypto_cipher *)
62 tfm));
63 ctx->fallback = fallback;
Marcelo H. Cerri86765902015-02-06 14:57:22 -020064
Herbert Xu4beb1062015-06-15 16:55:46 +080065 return 0;
Marcelo H. Cerri86765902015-02-06 14:57:22 -020066}
67
68static void p8_aes_exit(struct crypto_tfm *tfm)
69{
Herbert Xu4beb1062015-06-15 16:55:46 +080070 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerri86765902015-02-06 14:57:22 -020071
Herbert Xu4beb1062015-06-15 16:55:46 +080072 if (ctx->fallback) {
73 crypto_free_cipher(ctx->fallback);
74 ctx->fallback = NULL;
75 }
Marcelo H. Cerri86765902015-02-06 14:57:22 -020076}
77
78static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key,
Herbert Xu4beb1062015-06-15 16:55:46 +080079 unsigned int keylen)
Marcelo H. Cerri86765902015-02-06 14:57:22 -020080{
Herbert Xu4beb1062015-06-15 16:55:46 +080081 int ret;
82 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerri86765902015-02-06 14:57:22 -020083
Linus Torvalds44d21c32015-06-22 21:04:48 -070084 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +080085 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -030086 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +080087 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);
Anton Blancharddc4fbba2015-10-29 11:44:05 +110089 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +080090 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -070091 preempt_enable();
David Hildenbrand5f76eea2015-05-11 17:52:18 +020092
Herbert Xu4beb1062015-06-15 16:55:46 +080093 ret += crypto_cipher_setkey(ctx->fallback, key, keylen);
94 return ret;
Marcelo H. Cerri86765902015-02-06 14:57:22 -020095}
96
97static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
98{
Herbert Xu4beb1062015-06-15 16:55:46 +080099 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerri86765902015-02-06 14:57:22 -0200100
Herbert Xu4beb1062015-06-15 16:55:46 +0800101 if (in_interrupt()) {
102 crypto_cipher_encrypt_one(ctx->fallback, dst, src);
103 } else {
Linus Torvalds44d21c32015-06-22 21:04:48 -0700104 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800105 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -0300106 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800107 aes_p8_encrypt(src, dst, &ctx->enc_key);
Anton Blancharddc4fbba2015-10-29 11:44:05 +1100108 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800109 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -0700110 preempt_enable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800111 }
Marcelo H. Cerri86765902015-02-06 14:57:22 -0200112}
113
114static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
115{
Herbert Xu4beb1062015-06-15 16:55:46 +0800116 struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerri86765902015-02-06 14:57:22 -0200117
Herbert Xu4beb1062015-06-15 16:55:46 +0800118 if (in_interrupt()) {
119 crypto_cipher_decrypt_one(ctx->fallback, dst, src);
120 } else {
Linus Torvalds44d21c32015-06-22 21:04:48 -0700121 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800122 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -0300123 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800124 aes_p8_decrypt(src, dst, &ctx->dec_key);
Anton Blancharddc4fbba2015-10-29 11:44:05 +1100125 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800126 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -0700127 preempt_enable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800128 }
Marcelo H. Cerri86765902015-02-06 14:57:22 -0200129}
130
131struct crypto_alg p8_aes_alg = {
Herbert Xu4beb1062015-06-15 16:55:46 +0800132 .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 },
Marcelo H. Cerri86765902015-02-06 14:57:22 -0200150};