summaryrefslogtreecommitdiff
path: root/arch/x86/crypto/aegis128-aesni-glue.c
blob: 46d22712264309b65c2f96c4a691d01d7ed1398c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * The AEGIS-128 Authenticated-Encryption Algorithm
 *   Glue for AES-NI + SSE2 implementation
 *
 * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com>
 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
 */

#include <crypto/internal/aead.h>
#include <crypto/internal/simd.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/module.h>
#include <asm/fpu/api.h>
#include <asm/cpu_device_id.h>

#define AEGIS128_BLOCK_ALIGN 16
#define AEGIS128_BLOCK_SIZE 16
#define AEGIS128_NONCE_SIZE 16
#define AEGIS128_STATE_BLOCKS 5
#define AEGIS128_KEY_SIZE 16
#define AEGIS128_MIN_AUTH_SIZE 8
#define AEGIS128_MAX_AUTH_SIZE 16

asmlinkage void crypto_aegis128_aesni_init(void *state, void *key, void *iv);

asmlinkage void crypto_aegis128_aesni_ad(
		void *state, unsigned int length, const void *data);

asmlinkage void crypto_aegis128_aesni_enc(
		void *state, unsigned int length, const void *src, void *dst);

asmlinkage void crypto_aegis128_aesni_dec(
		void *state, unsigned int length, const void *src, void *dst);

asmlinkage void crypto_aegis128_aesni_enc_tail(
		void *state, unsigned int length, const void *src, void *dst);

asmlinkage void crypto_aegis128_aesni_dec_tail(
		void *state, unsigned int length, const void *src, void *dst);

asmlinkage void crypto_aegis128_aesni_final(
		void *state, void *tag_xor, unsigned int cryptlen,
		unsigned int assoclen);

struct aegis_block {
	u8 bytes[AEGIS128_BLOCK_SIZE] __aligned(AEGIS128_BLOCK_ALIGN);
};

struct aegis_state {
	struct aegis_block blocks[AEGIS128_STATE_BLOCKS];
};

struct aegis_ctx {
	struct aegis_block key;
};

struct aegis_crypt_ops {
	int (*skcipher_walk_init)(struct skcipher_walk *walk,
				  struct aead_request *req, bool atomic);

	void (*crypt_blocks)(void *state, unsigned int length, const void *src,
			     void *dst);
	void (*crypt_tail)(void *state, unsigned int length, const void *src,
			   void *dst);
};

static void crypto_aegis128_aesni_process_ad(
		struct aegis_state *state, struct scatterlist *sg_src,
		unsigned int assoclen)
{
	struct scatter_walk walk;
	struct aegis_block buf;
	unsigned int pos = 0;

	scatterwalk_start(&walk, sg_src);
	while (assoclen != 0) {
		unsigned int size = scatterwalk_clamp(&walk, assoclen);
		unsigned int left = size;
		void *mapped = scatterwalk_map(&walk);
		const u8 *src = (const u8 *)mapped;

		if (pos + size >= AEGIS128_BLOCK_SIZE) {
			if (pos > 0) {
				unsigned int fill = AEGIS128_BLOCK_SIZE - pos;
				memcpy(buf.bytes + pos, src, fill);
				crypto_aegis128_aesni_ad(state,
							 AEGIS128_BLOCK_SIZE,
							 buf.bytes);
				pos = 0;
				left -= fill;
				src += fill;
			}

			crypto_aegis128_aesni_ad(state, left, src);

			src += left & ~(AEGIS128_BLOCK_SIZE - 1);
			left &= AEGIS128_BLOCK_SIZE - 1;
		}

		memcpy(buf.bytes + pos, src, left);
		pos += left;
		assoclen -= size;

		scatterwalk_unmap(mapped);
		scatterwalk_advance(&walk, size);
		scatterwalk_done(&walk, 0, assoclen);
	}

	if (pos > 0) {
		memset(buf.bytes + pos, 0, AEGIS128_BLOCK_SIZE - pos);
		crypto_aegis128_aesni_ad(state, AEGIS128_BLOCK_SIZE, buf.bytes);
	}
}

static void crypto_aegis128_aesni_process_crypt(
		struct aegis_state *state, struct skcipher_walk *walk,
		const struct aegis_crypt_ops *ops)
{
	while (walk->nbytes >= AEGIS128_BLOCK_SIZE) {
		ops->crypt_blocks(state,
				  round_down(walk->nbytes, AEGIS128_BLOCK_SIZE),
				  walk->src.virt.addr, walk->dst.virt.addr);
		skcipher_walk_done(walk, walk->nbytes % AEGIS128_BLOCK_SIZE);
	}

	if (walk->nbytes) {
		ops->crypt_tail(state, walk->nbytes, walk->src.virt.addr,
				walk->dst.virt.addr);
		skcipher_walk_done(walk, 0);
	}
}

static struct aegis_ctx *crypto_aegis128_aesni_ctx(struct crypto_aead *aead)
{
	u8 *ctx = crypto_aead_ctx(aead);
	ctx = PTR_ALIGN(ctx, __alignof__(struct aegis_ctx));
	return (void *)ctx;
}

static int crypto_aegis128_aesni_setkey(struct crypto_aead *aead, const u8 *key,
					unsigned int keylen)
{
	struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(aead);

	if (keylen != AEGIS128_KEY_SIZE) {
		crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
		return -EINVAL;
	}

	memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE);

	return 0;
}

static int crypto_aegis128_aesni_setauthsize(struct crypto_aead *tfm,
						unsigned int authsize)
{
	if (authsize > AEGIS128_MAX_AUTH_SIZE)
		return -EINVAL;
	if (authsize < AEGIS128_MIN_AUTH_SIZE)
		return -EINVAL;
	return 0;
}

static void crypto_aegis128_aesni_crypt(struct aead_request *req,
					struct aegis_block *tag_xor,
					unsigned int cryptlen,
					const struct aegis_crypt_ops *ops)
{
	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(tfm);
	struct skcipher_walk walk;
	struct aegis_state state;

	ops->skcipher_walk_init(&walk, req, true);

	kernel_fpu_begin();

	crypto_aegis128_aesni_init(&state, ctx->key.bytes, req->iv);
	crypto_aegis128_aesni_process_ad(&state, req->src, req->assoclen);
	crypto_aegis128_aesni_process_crypt(&state, &walk, ops);
	crypto_aegis128_aesni_final(&state, tag_xor, req->assoclen, cryptlen);

	kernel_fpu_end();
}

static int crypto_aegis128_aesni_encrypt(struct aead_request *req)
{
	static const struct aegis_crypt_ops OPS = {
		.skcipher_walk_init = skcipher_walk_aead_encrypt,
		.crypt_blocks = crypto_aegis128_aesni_enc,
		.crypt_tail = crypto_aegis128_aesni_enc_tail,
	};

	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct aegis_block tag = {};
	unsigned int authsize = crypto_aead_authsize(tfm);
	unsigned int cryptlen = req->cryptlen;

	crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS);

	scatterwalk_map_and_copy(tag.bytes, req->dst,
				 req->assoclen + cryptlen, authsize, 1);
	return 0;
}

static int crypto_aegis128_aesni_decrypt(struct aead_request *req)
{
	static const struct aegis_block zeros = {};

	static const struct aegis_crypt_ops OPS = {
		.skcipher_walk_init = skcipher_walk_aead_decrypt,
		.crypt_blocks = crypto_aegis128_aesni_dec,
		.crypt_tail = crypto_aegis128_aesni_dec_tail,
	};

	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct aegis_block tag;
	unsigned int authsize = crypto_aead_authsize(tfm);
	unsigned int cryptlen = req->cryptlen - authsize;

	scatterwalk_map_and_copy(tag.bytes, req->src,
				 req->assoclen + cryptlen, authsize, 0);

	crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS);

	return crypto_memneq(tag.bytes, zeros.bytes, authsize) ? -EBADMSG : 0;
}

static int crypto_aegis128_aesni_init_tfm(struct crypto_aead *aead)
{
	return 0;
}

static void crypto_aegis128_aesni_exit_tfm(struct crypto_aead *aead)
{
}

static struct aead_alg crypto_aegis128_aesni_alg = {
	.setkey = crypto_aegis128_aesni_setkey,
	.setauthsize = crypto_aegis128_aesni_setauthsize,
	.encrypt = crypto_aegis128_aesni_encrypt,
	.decrypt = crypto_aegis128_aesni_decrypt,
	.init = crypto_aegis128_aesni_init_tfm,
	.exit = crypto_aegis128_aesni_exit_tfm,

	.ivsize = AEGIS128_NONCE_SIZE,
	.maxauthsize = AEGIS128_MAX_AUTH_SIZE,
	.chunksize = AEGIS128_BLOCK_SIZE,

	.base = {
		.cra_flags = CRYPTO_ALG_INTERNAL,
		.cra_blocksize = 1,
		.cra_ctxsize = sizeof(struct aegis_ctx) +
			       __alignof__(struct aegis_ctx),
		.cra_alignmask = 0,
		.cra_priority = 400,

		.cra_name = "__aegis128",
		.cra_driver_name = "__aegis128-aesni",

		.cra_module = THIS_MODULE,
	}
};

static struct simd_aead_alg *simd_alg;

static int __init crypto_aegis128_aesni_module_init(void)
{
	if (!boot_cpu_has(X86_FEATURE_XMM2) ||
	    !boot_cpu_has(X86_FEATURE_AES) ||
	    !cpu_has_xfeatures(XFEATURE_MASK_SSE, NULL))
		return -ENODEV;

	return simd_register_aeads_compat(&crypto_aegis128_aesni_alg, 1,
					  &simd_alg);
}

static void __exit crypto_aegis128_aesni_module_exit(void)
{
	simd_unregister_aeads(&crypto_aegis128_aesni_alg, 1, &simd_alg);
}

module_init(crypto_aegis128_aesni_module_init);
module_exit(crypto_aegis128_aesni_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm -- AESNI+SSE2 implementation");
MODULE_ALIAS_CRYPTO("aegis128");
MODULE_ALIAS_CRYPTO("aegis128-aesni");