blob: 27a94a11900926d9614d5a747f7e95d07f21afb1 [file] [log] [blame]
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -02001/**
2 * GHASH 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>
Marcelo Cerri80da44c2016-09-28 13:42:10 -030029#include <crypto/ghash.h>
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020030#include <crypto/scatterwalk.h>
31#include <crypto/internal/hash.h>
32#include <crypto/b128ops.h>
33
34#define IN_INTERRUPT in_interrupt()
35
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020036void gcm_init_p8(u128 htable[16], const u64 Xi[2]);
37void gcm_gmult_p8(u64 Xi[2], const u128 htable[16]);
38void gcm_ghash_p8(u64 Xi[2], const u128 htable[16],
Herbert Xu4beb1062015-06-15 16:55:46 +080039 const u8 *in, size_t len);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020040
41struct p8_ghash_ctx {
Herbert Xu4beb1062015-06-15 16:55:46 +080042 u128 htable[16];
43 struct crypto_shash *fallback;
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020044};
45
46struct p8_ghash_desc_ctx {
Herbert Xu4beb1062015-06-15 16:55:46 +080047 u64 shash[2];
48 u8 buffer[GHASH_DIGEST_SIZE];
49 int bytes;
50 struct shash_desc fallback_desc;
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020051};
52
53static int p8_ghash_init_tfm(struct crypto_tfm *tfm)
54{
Marcelo Cerri80da44c2016-09-28 13:42:10 -030055 const char *alg = "ghash-generic";
Herbert Xu4beb1062015-06-15 16:55:46 +080056 struct crypto_shash *fallback;
57 struct crypto_shash *shash_tfm = __crypto_shash_cast(tfm);
58 struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020059
Herbert Xu4beb1062015-06-15 16:55:46 +080060 fallback = crypto_alloc_shash(alg, 0, CRYPTO_ALG_NEED_FALLBACK);
61 if (IS_ERR(fallback)) {
62 printk(KERN_ERR
63 "Failed to allocate transformation for '%s': %ld\n",
64 alg, PTR_ERR(fallback));
65 return PTR_ERR(fallback);
66 }
67 printk(KERN_INFO "Using '%s' as fallback implementation.\n",
68 crypto_tfm_alg_driver_name(crypto_shash_tfm(fallback)));
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020069
Herbert Xu4beb1062015-06-15 16:55:46 +080070 crypto_shash_set_flags(fallback,
71 crypto_shash_get_flags((struct crypto_shash
72 *) tfm));
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020073
Marcelo Cerri80da44c2016-09-28 13:42:10 -030074 /* Check if the descsize defined in the algorithm is still enough. */
75 if (shash_tfm->descsize < sizeof(struct p8_ghash_desc_ctx)
76 + crypto_shash_descsize(fallback)) {
77 printk(KERN_ERR
78 "Desc size of the fallback implementation (%s) does not match the expected value: %lu vs %u\n",
79 alg,
80 shash_tfm->descsize - sizeof(struct p8_ghash_desc_ctx),
81 crypto_shash_descsize(fallback));
82 return -EINVAL;
83 }
84 ctx->fallback = fallback;
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020085
Herbert Xu4beb1062015-06-15 16:55:46 +080086 return 0;
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020087}
88
89static void p8_ghash_exit_tfm(struct crypto_tfm *tfm)
90{
Herbert Xu4beb1062015-06-15 16:55:46 +080091 struct p8_ghash_ctx *ctx = crypto_tfm_ctx(tfm);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020092
Herbert Xu4beb1062015-06-15 16:55:46 +080093 if (ctx->fallback) {
94 crypto_free_shash(ctx->fallback);
95 ctx->fallback = NULL;
96 }
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -020097}
98
99static int p8_ghash_init(struct shash_desc *desc)
100{
Herbert Xu4beb1062015-06-15 16:55:46 +0800101 struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm));
102 struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200103
Herbert Xu4beb1062015-06-15 16:55:46 +0800104 dctx->bytes = 0;
105 memset(dctx->shash, 0, GHASH_DIGEST_SIZE);
106 dctx->fallback_desc.tfm = ctx->fallback;
107 dctx->fallback_desc.flags = desc->flags;
108 return crypto_shash_init(&dctx->fallback_desc);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200109}
110
111static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key,
Herbert Xu4beb1062015-06-15 16:55:46 +0800112 unsigned int keylen)
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200113{
Herbert Xu4beb1062015-06-15 16:55:46 +0800114 struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(tfm));
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200115
Marcelo Cerri80da44c2016-09-28 13:42:10 -0300116 if (keylen != GHASH_BLOCK_SIZE)
Herbert Xu4beb1062015-06-15 16:55:46 +0800117 return -EINVAL;
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200118
Linus Torvalds44d21c32015-06-22 21:04:48 -0700119 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800120 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -0300121 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800122 gcm_init_p8(ctx->htable, (const u64 *) key);
Anton Blancharddc4fbba2015-10-29 11:44:05 +1100123 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800124 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -0700125 preempt_enable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800126 return crypto_shash_setkey(ctx->fallback, key, keylen);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200127}
128
129static int p8_ghash_update(struct shash_desc *desc,
Herbert Xu4beb1062015-06-15 16:55:46 +0800130 const u8 *src, unsigned int srclen)
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200131{
Herbert Xu4beb1062015-06-15 16:55:46 +0800132 unsigned int len;
133 struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm));
134 struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200135
Herbert Xu4beb1062015-06-15 16:55:46 +0800136 if (IN_INTERRUPT) {
137 return crypto_shash_update(&dctx->fallback_desc, src,
138 srclen);
139 } else {
140 if (dctx->bytes) {
141 if (dctx->bytes + srclen < GHASH_DIGEST_SIZE) {
142 memcpy(dctx->buffer + dctx->bytes, src,
143 srclen);
144 dctx->bytes += srclen;
145 return 0;
146 }
147 memcpy(dctx->buffer + dctx->bytes, src,
148 GHASH_DIGEST_SIZE - dctx->bytes);
Linus Torvalds44d21c32015-06-22 21:04:48 -0700149 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800150 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -0300151 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800152 gcm_ghash_p8(dctx->shash, ctx->htable,
153 dctx->buffer, GHASH_DIGEST_SIZE);
Anton Blancharddc4fbba2015-10-29 11:44:05 +1100154 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800155 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -0700156 preempt_enable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800157 src += GHASH_DIGEST_SIZE - dctx->bytes;
158 srclen -= GHASH_DIGEST_SIZE - dctx->bytes;
159 dctx->bytes = 0;
160 }
161 len = srclen & ~(GHASH_DIGEST_SIZE - 1);
162 if (len) {
Linus Torvalds44d21c32015-06-22 21:04:48 -0700163 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800164 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -0300165 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800166 gcm_ghash_p8(dctx->shash, ctx->htable, src, len);
Anton Blancharddc4fbba2015-10-29 11:44:05 +1100167 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800168 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -0700169 preempt_enable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800170 src += len;
171 srclen -= len;
172 }
173 if (srclen) {
174 memcpy(dctx->buffer, src, srclen);
175 dctx->bytes = srclen;
176 }
177 return 0;
178 }
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200179}
180
181static int p8_ghash_final(struct shash_desc *desc, u8 *out)
182{
Herbert Xu4beb1062015-06-15 16:55:46 +0800183 int i;
184 struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm));
185 struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc);
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200186
Herbert Xu4beb1062015-06-15 16:55:46 +0800187 if (IN_INTERRUPT) {
188 return crypto_shash_final(&dctx->fallback_desc, out);
189 } else {
190 if (dctx->bytes) {
191 for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++)
192 dctx->buffer[i] = 0;
Linus Torvalds44d21c32015-06-22 21:04:48 -0700193 preempt_disable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800194 pagefault_disable();
Leonidas Da Silva Barbosa2d6f0602015-07-13 13:51:39 -0300195 enable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800196 gcm_ghash_p8(dctx->shash, ctx->htable,
197 dctx->buffer, GHASH_DIGEST_SIZE);
Anton Blancharddc4fbba2015-10-29 11:44:05 +1100198 disable_kernel_vsx();
Herbert Xu4beb1062015-06-15 16:55:46 +0800199 pagefault_enable();
Linus Torvalds44d21c32015-06-22 21:04:48 -0700200 preempt_enable();
Herbert Xu4beb1062015-06-15 16:55:46 +0800201 dctx->bytes = 0;
202 }
203 memcpy(out, dctx->shash, GHASH_DIGEST_SIZE);
204 return 0;
205 }
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200206}
207
208struct shash_alg p8_ghash_alg = {
Herbert Xu4beb1062015-06-15 16:55:46 +0800209 .digestsize = GHASH_DIGEST_SIZE,
210 .init = p8_ghash_init,
211 .update = p8_ghash_update,
212 .final = p8_ghash_final,
213 .setkey = p8_ghash_setkey,
Marcelo Cerri80da44c2016-09-28 13:42:10 -0300214 .descsize = sizeof(struct p8_ghash_desc_ctx)
215 + sizeof(struct ghash_desc_ctx),
Herbert Xu4beb1062015-06-15 16:55:46 +0800216 .base = {
217 .cra_name = "ghash",
218 .cra_driver_name = "p8_ghash",
219 .cra_priority = 1000,
220 .cra_flags = CRYPTO_ALG_TYPE_SHASH | CRYPTO_ALG_NEED_FALLBACK,
221 .cra_blocksize = GHASH_BLOCK_SIZE,
222 .cra_ctxsize = sizeof(struct p8_ghash_ctx),
223 .cra_module = THIS_MODULE,
224 .cra_init = p8_ghash_init_tfm,
225 .cra_exit = p8_ghash_exit_tfm,
226 },
Marcelo H. Cerricc333cd2015-02-06 14:59:05 -0200227};