Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 1 | /** |
| 2 | * AES CTR 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 | #include <crypto/scatterwalk.h> |
| 30 | #include "aesp8-ppc.h" |
| 31 | |
| 32 | struct p8_aes_ctr_ctx { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 33 | struct crypto_blkcipher *fallback; |
| 34 | struct aes_key enc_key; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 35 | }; |
| 36 | |
| 37 | static int p8_aes_ctr_init(struct crypto_tfm *tfm) |
| 38 | { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 39 | const char *alg; |
| 40 | struct crypto_blkcipher *fallback; |
| 41 | struct p8_aes_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 42 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 43 | if (!(alg = crypto_tfm_alg_name(tfm))) { |
| 44 | printk(KERN_ERR "Failed to get algorithm name.\n"); |
| 45 | return -ENOENT; |
| 46 | } |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 47 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 48 | fallback = |
| 49 | crypto_alloc_blkcipher(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. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 58 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 59 | crypto_blkcipher_set_flags( |
| 60 | fallback, |
| 61 | crypto_blkcipher_get_flags((struct crypto_blkcipher *)tfm)); |
| 62 | ctx->fallback = fallback; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 63 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 64 | return 0; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 65 | } |
| 66 | |
| 67 | static void p8_aes_ctr_exit(struct crypto_tfm *tfm) |
| 68 | { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 69 | struct p8_aes_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 70 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 71 | if (ctx->fallback) { |
| 72 | crypto_free_blkcipher(ctx->fallback); |
| 73 | ctx->fallback = NULL; |
| 74 | } |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 75 | } |
| 76 | |
| 77 | static int p8_aes_ctr_setkey(struct crypto_tfm *tfm, const u8 *key, |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 78 | unsigned int keylen) |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 79 | { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 80 | int ret; |
| 81 | struct p8_aes_ctr_ctx *ctx = crypto_tfm_ctx(tfm); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 82 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 83 | pagefault_disable(); |
Leonidas Da Silva Barbosa | 2d6f060 | 2015-07-13 13:51:39 -0300 | [diff] [blame] | 84 | enable_kernel_vsx(); |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 85 | ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); |
Anton Blanchard | dc4fbba | 2015-10-29 11:44:05 +1100 | [diff] [blame] | 86 | disable_kernel_vsx(); |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 87 | pagefault_enable(); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 88 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 89 | ret += crypto_blkcipher_setkey(ctx->fallback, key, keylen); |
| 90 | return ret; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | static void p8_aes_ctr_final(struct p8_aes_ctr_ctx *ctx, |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 94 | struct blkcipher_walk *walk) |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 95 | { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 96 | u8 *ctrblk = walk->iv; |
| 97 | u8 keystream[AES_BLOCK_SIZE]; |
| 98 | u8 *src = walk->src.virt.addr; |
| 99 | u8 *dst = walk->dst.virt.addr; |
| 100 | unsigned int nbytes = walk->nbytes; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 101 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 102 | pagefault_disable(); |
Leonidas Da Silva Barbosa | 2d6f060 | 2015-07-13 13:51:39 -0300 | [diff] [blame] | 103 | enable_kernel_vsx(); |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 104 | aes_p8_encrypt(ctrblk, keystream, &ctx->enc_key); |
Anton Blanchard | dc4fbba | 2015-10-29 11:44:05 +1100 | [diff] [blame] | 105 | disable_kernel_vsx(); |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 106 | pagefault_enable(); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 107 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 108 | crypto_xor(keystream, src, nbytes); |
| 109 | memcpy(dst, keystream, nbytes); |
| 110 | crypto_inc(ctrblk, AES_BLOCK_SIZE); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | static int p8_aes_ctr_crypt(struct blkcipher_desc *desc, |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 114 | struct scatterlist *dst, |
| 115 | struct scatterlist *src, unsigned int nbytes) |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 116 | { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 117 | int ret; |
Leonidas Da Silva Barbosa | 1d4aa0b | 2015-08-14 10:12:22 -0300 | [diff] [blame] | 118 | u64 inc; |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 119 | struct blkcipher_walk walk; |
| 120 | struct p8_aes_ctr_ctx *ctx = |
| 121 | crypto_tfm_ctx(crypto_blkcipher_tfm(desc->tfm)); |
| 122 | struct blkcipher_desc fallback_desc = { |
| 123 | .tfm = ctx->fallback, |
| 124 | .info = desc->info, |
| 125 | .flags = desc->flags |
| 126 | }; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 127 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 128 | if (in_interrupt()) { |
| 129 | ret = crypto_blkcipher_encrypt(&fallback_desc, dst, src, |
| 130 | nbytes); |
| 131 | } else { |
| 132 | blkcipher_walk_init(&walk, dst, src, nbytes); |
| 133 | ret = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE); |
| 134 | while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) { |
| 135 | pagefault_disable(); |
Leonidas Da Silva Barbosa | 2d6f060 | 2015-07-13 13:51:39 -0300 | [diff] [blame] | 136 | enable_kernel_vsx(); |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 137 | aes_p8_ctr32_encrypt_blocks(walk.src.virt.addr, |
| 138 | walk.dst.virt.addr, |
| 139 | (nbytes & |
| 140 | AES_BLOCK_MASK) / |
| 141 | AES_BLOCK_SIZE, |
| 142 | &ctx->enc_key, |
| 143 | walk.iv); |
Anton Blanchard | dc4fbba | 2015-10-29 11:44:05 +1100 | [diff] [blame] | 144 | disable_kernel_vsx(); |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 145 | pagefault_enable(); |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 146 | |
Leonidas Da Silva Barbosa | 1d4aa0b | 2015-08-14 10:12:22 -0300 | [diff] [blame] | 147 | /* We need to update IV mostly for last bytes/round */ |
| 148 | inc = (nbytes & AES_BLOCK_MASK) / AES_BLOCK_SIZE; |
| 149 | if (inc > 0) |
| 150 | while (inc--) |
| 151 | crypto_inc(walk.iv, AES_BLOCK_SIZE); |
| 152 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 153 | nbytes &= AES_BLOCK_SIZE - 1; |
| 154 | ret = blkcipher_walk_done(desc, &walk, nbytes); |
| 155 | } |
| 156 | if (walk.nbytes) { |
| 157 | p8_aes_ctr_final(ctx, &walk); |
| 158 | ret = blkcipher_walk_done(desc, &walk, 0); |
| 159 | } |
| 160 | } |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 161 | |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 162 | return ret; |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 163 | } |
| 164 | |
| 165 | struct crypto_alg p8_aes_ctr_alg = { |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 166 | .cra_name = "ctr(aes)", |
| 167 | .cra_driver_name = "p8_aes_ctr", |
| 168 | .cra_module = THIS_MODULE, |
Anton Blanchard | 12d3f49 | 2016-06-10 16:47:03 +1000 | [diff] [blame] | 169 | .cra_priority = 2000, |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 170 | .cra_type = &crypto_blkcipher_type, |
| 171 | .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | CRYPTO_ALG_NEED_FALLBACK, |
| 172 | .cra_alignmask = 0, |
| 173 | .cra_blocksize = 1, |
| 174 | .cra_ctxsize = sizeof(struct p8_aes_ctr_ctx), |
| 175 | .cra_init = p8_aes_ctr_init, |
| 176 | .cra_exit = p8_aes_ctr_exit, |
| 177 | .cra_blkcipher = { |
Leonidas Da Silva Barbosa | 0d3d054 | 2015-11-30 16:19:03 -0200 | [diff] [blame] | 178 | .ivsize = AES_BLOCK_SIZE, |
Herbert Xu | 4beb106 | 2015-06-15 16:55:46 +0800 | [diff] [blame] | 179 | .min_keysize = AES_MIN_KEY_SIZE, |
| 180 | .max_keysize = AES_MAX_KEY_SIZE, |
| 181 | .setkey = p8_aes_ctr_setkey, |
| 182 | .encrypt = p8_aes_ctr_crypt, |
| 183 | .decrypt = p8_aes_ctr_crypt, |
| 184 | }, |
Marcelo H. Cerri | 4f7f60d | 2015-02-06 14:58:31 -0200 | [diff] [blame] | 185 | }; |