1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * The AEGIS-128 Authenticated-Encryption Algorithm
4 * Glue for AES-NI + SSE2 implementation
5 *
6 * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com>
7 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
8 */
9
10 #include <crypto/internal/aead.h>
11 #include <crypto/internal/simd.h>
12 #include <crypto/internal/skcipher.h>
13 #include <crypto/scatterwalk.h>
14 #include <linux/module.h>
15 #include <asm/fpu/api.h>
16 #include <asm/cpu_device_id.h>
17
18 #define AEGIS128_BLOCK_ALIGN 16
19 #define AEGIS128_BLOCK_SIZE 16
20 #define AEGIS128_NONCE_SIZE 16
21 #define AEGIS128_STATE_BLOCKS 5
22 #define AEGIS128_KEY_SIZE 16
23 #define AEGIS128_MIN_AUTH_SIZE 8
24 #define AEGIS128_MAX_AUTH_SIZE 16
25
26 asmlinkage void crypto_aegis128_aesni_init(void *state, void *key, void *iv);
27
28 asmlinkage void crypto_aegis128_aesni_ad(
29 void *state, unsigned int length, const void *data);
30
31 asmlinkage void crypto_aegis128_aesni_enc(
32 void *state, unsigned int length, const void *src, void *dst);
33
34 asmlinkage void crypto_aegis128_aesni_dec(
35 void *state, unsigned int length, const void *src, void *dst);
36
37 asmlinkage void crypto_aegis128_aesni_enc_tail(
38 void *state, unsigned int length, const void *src, void *dst);
39
40 asmlinkage void crypto_aegis128_aesni_dec_tail(
41 void *state, unsigned int length, const void *src, void *dst);
42
43 asmlinkage void crypto_aegis128_aesni_final(
44 void *state, void *tag_xor, unsigned int cryptlen,
45 unsigned int assoclen);
46
47 struct aegis_block {
48 u8 bytes[AEGIS128_BLOCK_SIZE] __aligned(AEGIS128_BLOCK_ALIGN);
49 };
50
51 struct aegis_state {
52 struct aegis_block blocks[AEGIS128_STATE_BLOCKS];
53 };
54
55 struct aegis_ctx {
56 struct aegis_block key;
57 };
58
59 struct aegis_crypt_ops {
60 int (*skcipher_walk_init)(struct skcipher_walk *walk,
61 struct aead_request *req, bool atomic);
62
63 void (*crypt_blocks)(void *state, unsigned int length, const void *src,
64 void *dst);
65 void (*crypt_tail)(void *state, unsigned int length, const void *src,
66 void *dst);
67 };
68
69 static void crypto_aegis128_aesni_process_ad(
70 struct aegis_state *state, struct scatterlist *sg_src,
71 unsigned int assoclen)
72 {
73 struct scatter_walk walk;
74 struct aegis_block buf;
75 unsigned int pos = 0;
76
77 scatterwalk_start(&walk, sg_src);
78 while (assoclen != 0) {
79 unsigned int size = scatterwalk_clamp(&walk, assoclen);
80 unsigned int left = size;
81 void *mapped = scatterwalk_map(&walk);
82 const u8 *src = (const u8 *)mapped;
83
84 if (pos + size >= AEGIS128_BLOCK_SIZE) {
85 if (pos > 0) {
86 unsigned int fill = AEGIS128_BLOCK_SIZE - pos;
87 memcpy(buf.bytes + pos, src, fill);
88 crypto_aegis128_aesni_ad(state,
89 AEGIS128_BLOCK_SIZE,
90 buf.bytes);
91 pos = 0;
92 left -= fill;
93 src += fill;
94 }
95
96 crypto_aegis128_aesni_ad(state, left, src);
97
98 src += left & ~(AEGIS128_BLOCK_SIZE - 1);
99 left &= AEGIS128_BLOCK_SIZE - 1;
100 }
101
102 memcpy(buf.bytes + pos, src, left);
103 pos += left;
104 assoclen -= size;
105
106 scatterwalk_unmap(mapped);
107 scatterwalk_advance(&walk, size);
108 scatterwalk_done(&walk, 0, assoclen);
109 }
110
111 if (pos > 0) {
112 memset(buf.bytes + pos, 0, AEGIS128_BLOCK_SIZE - pos);
113 crypto_aegis128_aesni_ad(state, AEGIS128_BLOCK_SIZE, buf.bytes);
114 }
115 }
116
117 static void crypto_aegis128_aesni_process_crypt(
118 struct aegis_state *state, struct skcipher_walk *walk,
119 const struct aegis_crypt_ops *ops)
120 {
121 while (walk->nbytes >= AEGIS128_BLOCK_SIZE) {
122 ops->crypt_blocks(state,
123 round_down(walk->nbytes, AEGIS128_BLOCK_SIZE),
124 walk->src.virt.addr, walk->dst.virt.addr);
125 skcipher_walk_done(walk, walk->nbytes % AEGIS128_BLOCK_SIZE);
126 }
127
128 if (walk->nbytes) {
129 ops->crypt_tail(state, walk->nbytes, walk->src.virt.addr,
130 walk->dst.virt.addr);
131 skcipher_walk_done(walk, 0);
132 }
133 }
134
135 static struct aegis_ctx *crypto_aegis128_aesni_ctx(struct crypto_aead *aead)
136 {
137 u8 *ctx = crypto_aead_ctx(aead);
138 ctx = PTR_ALIGN(ctx, __alignof__(struct aegis_ctx));
139 return (void *)ctx;
140 }
141
142 static int crypto_aegis128_aesni_setkey(struct crypto_aead *aead, const u8 *key,
143 unsigned int keylen)
144 {
145 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(aead);
146
147 if (keylen != AEGIS128_KEY_SIZE)
148 return -EINVAL;
149
150 memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE);
151
152 return 0;
153 }
154
155 static int crypto_aegis128_aesni_setauthsize(struct crypto_aead *tfm,
156 unsigned int authsize)
157 {
158 if (authsize > AEGIS128_MAX_AUTH_SIZE)
159 return -EINVAL;
160 if (authsize < AEGIS128_MIN_AUTH_SIZE)
161 return -EINVAL;
162 return 0;
163 }
164
165 static void crypto_aegis128_aesni_crypt(struct aead_request *req,
166 struct aegis_block *tag_xor,
167 unsigned int cryptlen,
168 const struct aegis_crypt_ops *ops)
169 {
170 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
171 struct aegis_ctx *ctx = crypto_aegis128_aesni_ctx(tfm);
172 struct skcipher_walk walk;
173 struct aegis_state state;
174
175 ops->skcipher_walk_init(&walk, req, true);
176
177 kernel_fpu_begin();
178
179 crypto_aegis128_aesni_init(&state, ctx->key.bytes, req->iv);
180 crypto_aegis128_aesni_process_ad(&state, req->src, req->assoclen);
181 crypto_aegis128_aesni_process_crypt(&state, &walk, ops);
182 crypto_aegis128_aesni_final(&state, tag_xor, req->assoclen, cryptlen);
183
184 kernel_fpu_end();
185 }
186
187 static int crypto_aegis128_aesni_encrypt(struct aead_request *req)
188 {
189 static const struct aegis_crypt_ops OPS = {
190 .skcipher_walk_init = skcipher_walk_aead_encrypt,
191 .crypt_blocks = crypto_aegis128_aesni_enc,
192 .crypt_tail = crypto_aegis128_aesni_enc_tail,
193 };
194
195 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
196 struct aegis_block tag = {};
197 unsigned int authsize = crypto_aead_authsize(tfm);
198 unsigned int cryptlen = req->cryptlen;
199
200 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS);
201
202 scatterwalk_map_and_copy(tag.bytes, req->dst,
203 req->assoclen + cryptlen, authsize, 1);
204 return 0;
205 }
206
207 static int crypto_aegis128_aesni_decrypt(struct aead_request *req)
208 {
209 static const struct aegis_block zeros = {};
210
211 static const struct aegis_crypt_ops OPS = {
212 .skcipher_walk_init = skcipher_walk_aead_decrypt,
213 .crypt_blocks = crypto_aegis128_aesni_dec,
214 .crypt_tail = crypto_aegis128_aesni_dec_tail,
215 };
216
217 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
218 struct aegis_block tag;
219 unsigned int authsize = crypto_aead_authsize(tfm);
220 unsigned int cryptlen = req->cryptlen - authsize;
221
222 scatterwalk_map_and_copy(tag.bytes, req->src,
223 req->assoclen + cryptlen, authsize, 0);
224
225 crypto_aegis128_aesni_crypt(req, &tag, cryptlen, &OPS);
226
227 return crypto_memneq(tag.bytes, zeros.bytes, authsize) ? -EBADMSG : 0;
228 }
229
230 static int crypto_aegis128_aesni_init_tfm(struct crypto_aead *aead)
231 {
232 return 0;
233 }
234
235 static void crypto_aegis128_aesni_exit_tfm(struct crypto_aead *aead)
236 {
237 }
238
239 static struct aead_alg crypto_aegis128_aesni_alg = {
240 .setkey = crypto_aegis128_aesni_setkey,
241 .setauthsize = crypto_aegis128_aesni_setauthsize,
242 .encrypt = crypto_aegis128_aesni_encrypt,
243 .decrypt = crypto_aegis128_aesni_decrypt,
244 .init = crypto_aegis128_aesni_init_tfm,
245 .exit = crypto_aegis128_aesni_exit_tfm,
246
247 .ivsize = AEGIS128_NONCE_SIZE,
248 .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
249 .chunksize = AEGIS128_BLOCK_SIZE,
250
251 .base = {
252 .cra_flags = CRYPTO_ALG_INTERNAL,
253 .cra_blocksize = 1,
254 .cra_ctxsize = sizeof(struct aegis_ctx) +
255 __alignof__(struct aegis_ctx),
256 .cra_alignmask = 0,
257 .cra_priority = 400,
258
259 .cra_name = "__aegis128",
260 .cra_driver_name = "__aegis128-aesni",
261
262 .cra_module = THIS_MODULE,
263 }
264 };
265
266 static struct simd_aead_alg *simd_alg;
267
268 static int __init crypto_aegis128_aesni_module_init(void)
269 {
270 if (!boot_cpu_has(X86_FEATURE_XMM2) ||
271 !boot_cpu_has(X86_FEATURE_AES) ||
272 !cpu_has_xfeatures(XFEATURE_MASK_SSE, NULL))
273 return -ENODEV;
274
275 return simd_register_aeads_compat(&crypto_aegis128_aesni_alg, 1,
276 &simd_alg);
277 }
278
279 static void __exit crypto_aegis128_aesni_module_exit(void)
280 {
281 simd_unregister_aeads(&crypto_aegis128_aesni_alg, 1, &simd_alg);
282 }
283
284 module_init(crypto_aegis128_aesni_module_init);
285 module_exit(crypto_aegis128_aesni_module_exit);
286
287 MODULE_LICENSE("GPL");
288 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
289 MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm -- AESNI+SSE2 implementation");
290 MODULE_ALIAS_CRYPTO("aegis128");
291 MODULE_ALIAS_CRYPTO("aegis128-aesni");
292
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