1
2
3
4
5
6
7
8
9
10
11#include <asm/hwcap.h>
12#include <asm/neon.h>
13#include <asm/simd.h>
14#include <asm/unaligned.h>
15#include <crypto/cryptd.h>
16#include <crypto/internal/hash.h>
17#include <crypto/gf128mul.h>
18#include <linux/crypto.h>
19#include <linux/module.h>
20
21MODULE_DESCRIPTION("GHASH secure hash using ARMv8 Crypto Extensions");
22MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
23MODULE_LICENSE("GPL v2");
24
25#define GHASH_BLOCK_SIZE 16
26#define GHASH_DIGEST_SIZE 16
27
28struct ghash_key {
29 u64 a;
30 u64 b;
31};
32
33struct ghash_desc_ctx {
34 u64 digest[GHASH_DIGEST_SIZE/sizeof(u64)];
35 u8 buf[GHASH_BLOCK_SIZE];
36 u32 count;
37};
38
39struct ghash_async_ctx {
40 struct cryptd_ahash *cryptd_tfm;
41};
42
43asmlinkage void pmull_ghash_update(int blocks, u64 dg[], const char *src,
44 struct ghash_key const *k, const char *head);
45
46static int ghash_init(struct shash_desc *desc)
47{
48 struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
49
50 *ctx = (struct ghash_desc_ctx){};
51 return 0;
52}
53
54static int ghash_update(struct shash_desc *desc, const u8 *src,
55 unsigned int len)
56{
57 struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
58 unsigned int partial = ctx->count % GHASH_BLOCK_SIZE;
59
60 ctx->count += len;
61
62 if ((partial + len) >= GHASH_BLOCK_SIZE) {
63 struct ghash_key *key = crypto_shash_ctx(desc->tfm);
64 int blocks;
65
66 if (partial) {
67 int p = GHASH_BLOCK_SIZE - partial;
68
69 memcpy(ctx->buf + partial, src, p);
70 src += p;
71 len -= p;
72 }
73
74 blocks = len / GHASH_BLOCK_SIZE;
75 len %= GHASH_BLOCK_SIZE;
76
77 kernel_neon_begin();
78 pmull_ghash_update(blocks, ctx->digest, src, key,
79 partial ? ctx->buf : NULL);
80 kernel_neon_end();
81 src += blocks * GHASH_BLOCK_SIZE;
82 partial = 0;
83 }
84 if (len)
85 memcpy(ctx->buf + partial, src, len);
86 return 0;
87}
88
89static int ghash_final(struct shash_desc *desc, u8 *dst)
90{
91 struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
92 unsigned int partial = ctx->count % GHASH_BLOCK_SIZE;
93
94 if (partial) {
95 struct ghash_key *key = crypto_shash_ctx(desc->tfm);
96
97 memset(ctx->buf + partial, 0, GHASH_BLOCK_SIZE - partial);
98 kernel_neon_begin();
99 pmull_ghash_update(1, ctx->digest, ctx->buf, key, NULL);
100 kernel_neon_end();
101 }
102 put_unaligned_be64(ctx->digest[1], dst);
103 put_unaligned_be64(ctx->digest[0], dst + 8);
104
105 *ctx = (struct ghash_desc_ctx){};
106 return 0;
107}
108
109static int ghash_setkey(struct crypto_shash *tfm,
110 const u8 *inkey, unsigned int keylen)
111{
112 struct ghash_key *key = crypto_shash_ctx(tfm);
113 u64 a, b;
114
115 if (keylen != GHASH_BLOCK_SIZE) {
116 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
117 return -EINVAL;
118 }
119
120
121 b = get_unaligned_be64(inkey);
122 a = get_unaligned_be64(inkey + 8);
123
124 key->a = (a << 1) | (b >> 63);
125 key->b = (b << 1) | (a >> 63);
126
127 if (b >> 63)
128 key->b ^= 0xc200000000000000UL;
129
130 return 0;
131}
132
133static struct shash_alg ghash_alg = {
134 .digestsize = GHASH_DIGEST_SIZE,
135 .init = ghash_init,
136 .update = ghash_update,
137 .final = ghash_final,
138 .setkey = ghash_setkey,
139 .descsize = sizeof(struct ghash_desc_ctx),
140 .base = {
141 .cra_name = "__ghash",
142 .cra_driver_name = "__driver-ghash-ce",
143 .cra_priority = 0,
144 .cra_flags = CRYPTO_ALG_TYPE_SHASH | CRYPTO_ALG_INTERNAL,
145 .cra_blocksize = GHASH_BLOCK_SIZE,
146 .cra_ctxsize = sizeof(struct ghash_key),
147 .cra_module = THIS_MODULE,
148 },
149};
150
151static int ghash_async_init(struct ahash_request *req)
152{
153 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
154 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
155 struct ahash_request *cryptd_req = ahash_request_ctx(req);
156 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
157 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
158 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
159
160 desc->tfm = child;
161 desc->flags = req->base.flags;
162 return crypto_shash_init(desc);
163}
164
165static int ghash_async_update(struct ahash_request *req)
166{
167 struct ahash_request *cryptd_req = ahash_request_ctx(req);
168 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
169 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
170 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
171
172 if (!may_use_simd() ||
173 (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
174 memcpy(cryptd_req, req, sizeof(*req));
175 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
176 return crypto_ahash_update(cryptd_req);
177 } else {
178 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
179 return shash_ahash_update(req, desc);
180 }
181}
182
183static int ghash_async_final(struct ahash_request *req)
184{
185 struct ahash_request *cryptd_req = ahash_request_ctx(req);
186 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
187 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
188 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
189
190 if (!may_use_simd() ||
191 (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
192 memcpy(cryptd_req, req, sizeof(*req));
193 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
194 return crypto_ahash_final(cryptd_req);
195 } else {
196 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
197 return crypto_shash_final(desc, req->result);
198 }
199}
200
201static int ghash_async_digest(struct ahash_request *req)
202{
203 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
204 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
205 struct ahash_request *cryptd_req = ahash_request_ctx(req);
206 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
207
208 if (!may_use_simd() ||
209 (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
210 memcpy(cryptd_req, req, sizeof(*req));
211 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
212 return crypto_ahash_digest(cryptd_req);
213 } else {
214 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
215 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
216
217 desc->tfm = child;
218 desc->flags = req->base.flags;
219 return shash_ahash_digest(req, desc);
220 }
221}
222
223static int ghash_async_import(struct ahash_request *req, const void *in)
224{
225 struct ahash_request *cryptd_req = ahash_request_ctx(req);
226 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
227 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
228 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
229
230 desc->tfm = cryptd_ahash_child(ctx->cryptd_tfm);
231 desc->flags = req->base.flags;
232
233 return crypto_shash_import(desc, in);
234}
235
236static int ghash_async_export(struct ahash_request *req, void *out)
237{
238 struct ahash_request *cryptd_req = ahash_request_ctx(req);
239 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
240
241 return crypto_shash_export(desc, out);
242}
243
244static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
245 unsigned int keylen)
246{
247 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
248 struct crypto_ahash *child = &ctx->cryptd_tfm->base;
249 int err;
250
251 crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
252 crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
253 & CRYPTO_TFM_REQ_MASK);
254 err = crypto_ahash_setkey(child, key, keylen);
255 crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
256 & CRYPTO_TFM_RES_MASK);
257
258 return err;
259}
260
261static int ghash_async_init_tfm(struct crypto_tfm *tfm)
262{
263 struct cryptd_ahash *cryptd_tfm;
264 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
265
266 cryptd_tfm = cryptd_alloc_ahash("__driver-ghash-ce",
267 CRYPTO_ALG_INTERNAL,
268 CRYPTO_ALG_INTERNAL);
269 if (IS_ERR(cryptd_tfm))
270 return PTR_ERR(cryptd_tfm);
271 ctx->cryptd_tfm = cryptd_tfm;
272 crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
273 sizeof(struct ahash_request) +
274 crypto_ahash_reqsize(&cryptd_tfm->base));
275
276 return 0;
277}
278
279static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
280{
281 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
282
283 cryptd_free_ahash(ctx->cryptd_tfm);
284}
285
286static struct ahash_alg ghash_async_alg = {
287 .init = ghash_async_init,
288 .update = ghash_async_update,
289 .final = ghash_async_final,
290 .setkey = ghash_async_setkey,
291 .digest = ghash_async_digest,
292 .import = ghash_async_import,
293 .export = ghash_async_export,
294 .halg.digestsize = GHASH_DIGEST_SIZE,
295 .halg.statesize = sizeof(struct ghash_desc_ctx),
296 .halg.base = {
297 .cra_name = "ghash",
298 .cra_driver_name = "ghash-ce",
299 .cra_priority = 300,
300 .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
301 .cra_blocksize = GHASH_BLOCK_SIZE,
302 .cra_type = &crypto_ahash_type,
303 .cra_ctxsize = sizeof(struct ghash_async_ctx),
304 .cra_module = THIS_MODULE,
305 .cra_init = ghash_async_init_tfm,
306 .cra_exit = ghash_async_exit_tfm,
307 },
308};
309
310static int __init ghash_ce_mod_init(void)
311{
312 int err;
313
314 if (!(elf_hwcap2 & HWCAP2_PMULL))
315 return -ENODEV;
316
317 err = crypto_register_shash(&ghash_alg);
318 if (err)
319 return err;
320 err = crypto_register_ahash(&ghash_async_alg);
321 if (err)
322 goto err_shash;
323
324 return 0;
325
326err_shash:
327 crypto_unregister_shash(&ghash_alg);
328 return err;
329}
330
331static void __exit ghash_ce_mod_exit(void)
332{
333 crypto_unregister_ahash(&ghash_async_alg);
334 crypto_unregister_shash(&ghash_alg);
335}
336
337module_init(ghash_ce_mod_init);
338module_exit(ghash_ce_mod_exit);
339
