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13#include <linux/err.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/crypto.h>
18#include <crypto/algapi.h>
19#include <crypto/cryptd.h>
20#include <crypto/gf128mul.h>
21#include <crypto/internal/hash.h>
22#include <asm/fpu/api.h>
23#include <asm/cpu_device_id.h>
24
25#define GHASH_BLOCK_SIZE 16
26#define GHASH_DIGEST_SIZE 16
27
28void clmul_ghash_mul(char *dst, const u128 *shash);
29
30void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
31 const u128 *shash);
32
33struct ghash_async_ctx {
34 struct cryptd_ahash *cryptd_tfm;
35};
36
37struct ghash_ctx {
38 u128 shash;
39};
40
41struct ghash_desc_ctx {
42 u8 buffer[GHASH_BLOCK_SIZE];
43 u32 bytes;
44};
45
46static int ghash_init(struct shash_desc *desc)
47{
48 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
49
50 memset(dctx, 0, sizeof(*dctx));
51
52 return 0;
53}
54
55static int ghash_setkey(struct crypto_shash *tfm,
56 const u8 *key, unsigned int keylen)
57{
58 struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
59 be128 *x = (be128 *)key;
60 u64 a, b;
61
62 if (keylen != GHASH_BLOCK_SIZE) {
63 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
64 return -EINVAL;
65 }
66
67
68 a = be64_to_cpu(x->a);
69 b = be64_to_cpu(x->b);
70
71 ctx->shash.a = (b << 1) | (a >> 63);
72 ctx->shash.b = (a << 1) | (b >> 63);
73
74 if (a >> 63)
75 ctx->shash.b ^= ((u64)0xc2) << 56;
76
77 return 0;
78}
79
80static int ghash_update(struct shash_desc *desc,
81 const u8 *src, unsigned int srclen)
82{
83 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
84 struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
85 u8 *dst = dctx->buffer;
86
87 kernel_fpu_begin();
88 if (dctx->bytes) {
89 int n = min(srclen, dctx->bytes);
90 u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
91
92 dctx->bytes -= n;
93 srclen -= n;
94
95 while (n--)
96 *pos++ ^= *src++;
97
98 if (!dctx->bytes)
99 clmul_ghash_mul(dst, &ctx->shash);
100 }
101
102 clmul_ghash_update(dst, src, srclen, &ctx->shash);
103 kernel_fpu_end();
104
105 if (srclen & 0xf) {
106 src += srclen - (srclen & 0xf);
107 srclen &= 0xf;
108 dctx->bytes = GHASH_BLOCK_SIZE - srclen;
109 while (srclen--)
110 *dst++ ^= *src++;
111 }
112
113 return 0;
114}
115
116static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
117{
118 u8 *dst = dctx->buffer;
119
120 if (dctx->bytes) {
121 u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
122
123 while (dctx->bytes--)
124 *tmp++ ^= 0;
125
126 kernel_fpu_begin();
127 clmul_ghash_mul(dst, &ctx->shash);
128 kernel_fpu_end();
129 }
130
131 dctx->bytes = 0;
132}
133
134static int ghash_final(struct shash_desc *desc, u8 *dst)
135{
136 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
137 struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
138 u8 *buf = dctx->buffer;
139
140 ghash_flush(ctx, dctx);
141 memcpy(dst, buf, GHASH_BLOCK_SIZE);
142
143 return 0;
144}
145
146static struct shash_alg ghash_alg = {
147 .digestsize = GHASH_DIGEST_SIZE,
148 .init = ghash_init,
149 .update = ghash_update,
150 .final = ghash_final,
151 .setkey = ghash_setkey,
152 .descsize = sizeof(struct ghash_desc_ctx),
153 .base = {
154 .cra_name = "__ghash",
155 .cra_driver_name = "__ghash-pclmulqdqni",
156 .cra_priority = 0,
157 .cra_flags = CRYPTO_ALG_TYPE_SHASH |
158 CRYPTO_ALG_INTERNAL,
159 .cra_blocksize = GHASH_BLOCK_SIZE,
160 .cra_ctxsize = sizeof(struct ghash_ctx),
161 .cra_module = THIS_MODULE,
162 },
163};
164
165static int ghash_async_init(struct ahash_request *req)
166{
167 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
168 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
169 struct ahash_request *cryptd_req = ahash_request_ctx(req);
170 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
171 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
172 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
173
174 desc->tfm = child;
175 desc->flags = req->base.flags;
176 return crypto_shash_init(desc);
177}
178
179static int ghash_async_update(struct ahash_request *req)
180{
181 struct ahash_request *cryptd_req = ahash_request_ctx(req);
182 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
183 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
184 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
185
186 if (!irq_fpu_usable() ||
187 (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
188 memcpy(cryptd_req, req, sizeof(*req));
189 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
190 return crypto_ahash_update(cryptd_req);
191 } else {
192 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
193 return shash_ahash_update(req, desc);
194 }
195}
196
197static int ghash_async_final(struct ahash_request *req)
198{
199 struct ahash_request *cryptd_req = ahash_request_ctx(req);
200 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
201 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
202 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
203
204 if (!irq_fpu_usable() ||
205 (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
206 memcpy(cryptd_req, req, sizeof(*req));
207 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
208 return crypto_ahash_final(cryptd_req);
209 } else {
210 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
211 return crypto_shash_final(desc, req->result);
212 }
213}
214
215static int ghash_async_import(struct ahash_request *req, const void *in)
216{
217 struct ahash_request *cryptd_req = ahash_request_ctx(req);
218 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
219 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
220
221 ghash_async_init(req);
222 memcpy(dctx, in, sizeof(*dctx));
223 return 0;
224
225}
226
227static int ghash_async_export(struct ahash_request *req, void *out)
228{
229 struct ahash_request *cryptd_req = ahash_request_ctx(req);
230 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
231 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
232
233 memcpy(out, dctx, sizeof(*dctx));
234 return 0;
235
236}
237
238static int ghash_async_digest(struct ahash_request *req)
239{
240 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
241 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
242 struct ahash_request *cryptd_req = ahash_request_ctx(req);
243 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
244
245 if (!irq_fpu_usable() ||
246 (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
247 memcpy(cryptd_req, req, sizeof(*req));
248 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
249 return crypto_ahash_digest(cryptd_req);
250 } else {
251 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
252 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
253
254 desc->tfm = child;
255 desc->flags = req->base.flags;
256 return shash_ahash_digest(req, desc);
257 }
258}
259
260static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
261 unsigned int keylen)
262{
263 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
264 struct crypto_ahash *child = &ctx->cryptd_tfm->base;
265 int err;
266
267 crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
268 crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
269 & CRYPTO_TFM_REQ_MASK);
270 err = crypto_ahash_setkey(child, key, keylen);
271 crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
272 & CRYPTO_TFM_RES_MASK);
273
274 return err;
275}
276
277static int ghash_async_init_tfm(struct crypto_tfm *tfm)
278{
279 struct cryptd_ahash *cryptd_tfm;
280 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
281
282 cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni",
283 CRYPTO_ALG_INTERNAL,
284 CRYPTO_ALG_INTERNAL);
285 if (IS_ERR(cryptd_tfm))
286 return PTR_ERR(cryptd_tfm);
287 ctx->cryptd_tfm = cryptd_tfm;
288 crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
289 sizeof(struct ahash_request) +
290 crypto_ahash_reqsize(&cryptd_tfm->base));
291
292 return 0;
293}
294
295static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
296{
297 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
298
299 cryptd_free_ahash(ctx->cryptd_tfm);
300}
301
302static struct ahash_alg ghash_async_alg = {
303 .init = ghash_async_init,
304 .update = ghash_async_update,
305 .final = ghash_async_final,
306 .setkey = ghash_async_setkey,
307 .digest = ghash_async_digest,
308 .export = ghash_async_export,
309 .import = ghash_async_import,
310 .halg = {
311 .digestsize = GHASH_DIGEST_SIZE,
312 .statesize = sizeof(struct ghash_desc_ctx),
313 .base = {
314 .cra_name = "ghash",
315 .cra_driver_name = "ghash-clmulni",
316 .cra_priority = 400,
317 .cra_ctxsize = sizeof(struct ghash_async_ctx),
318 .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
319 .cra_blocksize = GHASH_BLOCK_SIZE,
320 .cra_type = &crypto_ahash_type,
321 .cra_module = THIS_MODULE,
322 .cra_init = ghash_async_init_tfm,
323 .cra_exit = ghash_async_exit_tfm,
324 },
325 },
326};
327
328static const struct x86_cpu_id pcmul_cpu_id[] = {
329 X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ),
330 {}
331};
332MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
333
334static int __init ghash_pclmulqdqni_mod_init(void)
335{
336 int err;
337
338 if (!x86_match_cpu(pcmul_cpu_id))
339 return -ENODEV;
340
341 err = crypto_register_shash(&ghash_alg);
342 if (err)
343 goto err_out;
344 err = crypto_register_ahash(&ghash_async_alg);
345 if (err)
346 goto err_shash;
347
348 return 0;
349
350err_shash:
351 crypto_unregister_shash(&ghash_alg);
352err_out:
353 return err;
354}
355
356static void __exit ghash_pclmulqdqni_mod_exit(void)
357{
358 crypto_unregister_ahash(&ghash_async_alg);
359 crypto_unregister_shash(&ghash_alg);
360}
361
362module_init(ghash_pclmulqdqni_mod_init);
363module_exit(ghash_pclmulqdqni_mod_exit);
364
365MODULE_LICENSE("GPL");
366MODULE_DESCRIPTION("GHASH Message Digest Algorithm, "
367 "acclerated by PCLMULQDQ-NI");
368MODULE_ALIAS_CRYPTO("ghash");
369
