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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
  4 * instructions. This file contains glue code.
  5 *
  6 * Copyright (c) 2009 Intel Corp.
  7 *   Author: Huang Ying <ying.huang@intel.com>
  8 */
  9
 10#include <linux/err.h>
 11#include <linux/module.h>
 12#include <linux/init.h>
 13#include <linux/kernel.h>
 14#include <linux/crypto.h>
 15#include <crypto/algapi.h>
 16#include <crypto/cryptd.h>
 17#include <crypto/gf128mul.h>
 18#include <crypto/internal/hash.h>
 19#include <crypto/internal/simd.h>
 20#include <asm/cpu_device_id.h>
 21#include <asm/simd.h>
 22#include <linux/unaligned.h>
 23
 24#define GHASH_BLOCK_SIZE	16
 25#define GHASH_DIGEST_SIZE	16
 26
 27void clmul_ghash_mul(char *dst, const le128 *shash);
 28
 29void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
 30			const le128 *shash);
 31
 32struct ghash_async_ctx {
 33	struct cryptd_ahash *cryptd_tfm;
 34};
 35
 36struct ghash_ctx {
 37	le128 shash;
 38};
 39
 40struct ghash_desc_ctx {
 41	u8 buffer[GHASH_BLOCK_SIZE];
 42	u32 bytes;
 43};
 44
 45static int ghash_init(struct shash_desc *desc)
 46{
 47	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 48
 49	memset(dctx, 0, sizeof(*dctx));
 50
 51	return 0;
 52}
 53
 54static int ghash_setkey(struct crypto_shash *tfm,
 55			const u8 *key, unsigned int keylen)
 56{
 57	struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
 
 58	u64 a, b;
 59
 60	if (keylen != GHASH_BLOCK_SIZE)
 61		return -EINVAL;
 62
 63	/*
 64	 * GHASH maps bits to polynomial coefficients backwards, which makes it
 65	 * hard to implement.  But it can be shown that the GHASH multiplication
 66	 *
 67	 *	D * K (mod x^128 + x^7 + x^2 + x + 1)
 68	 *
 69	 * (where D is a data block and K is the key) is equivalent to:
 70	 *
 71	 *	bitreflect(D) * bitreflect(K) * x^(-127)
 72	 *		(mod x^128 + x^127 + x^126 + x^121 + 1)
 73	 *
 74	 * So, the code below precomputes:
 75	 *
 76	 *	bitreflect(K) * x^(-127) (mod x^128 + x^127 + x^126 + x^121 + 1)
 77	 *
 78	 * ... but in Montgomery form (so that Montgomery multiplication can be
 79	 * used), i.e. with an extra x^128 factor, which means actually:
 80	 *
 81	 *	bitreflect(K) * x (mod x^128 + x^127 + x^126 + x^121 + 1)
 82	 *
 83	 * The within-a-byte part of bitreflect() cancels out GHASH's built-in
 84	 * reflection, and thus bitreflect() is actually a byteswap.
 85	 */
 86	a = get_unaligned_be64(key);
 87	b = get_unaligned_be64(key + 8);
 88	ctx->shash.a = cpu_to_le64((a << 1) | (b >> 63));
 89	ctx->shash.b = cpu_to_le64((b << 1) | (a >> 63));
 90	if (a >> 63)
 91		ctx->shash.a ^= cpu_to_le64((u64)0xc2 << 56);
 
 92	return 0;
 93}
 94
 95static int ghash_update(struct shash_desc *desc,
 96			 const u8 *src, unsigned int srclen)
 97{
 98	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 99	struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
100	u8 *dst = dctx->buffer;
101
102	kernel_fpu_begin();
103	if (dctx->bytes) {
104		int n = min(srclen, dctx->bytes);
105		u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
106
107		dctx->bytes -= n;
108		srclen -= n;
109
110		while (n--)
111			*pos++ ^= *src++;
112
113		if (!dctx->bytes)
114			clmul_ghash_mul(dst, &ctx->shash);
115	}
116
117	clmul_ghash_update(dst, src, srclen, &ctx->shash);
118	kernel_fpu_end();
119
120	if (srclen & 0xf) {
121		src += srclen - (srclen & 0xf);
122		srclen &= 0xf;
123		dctx->bytes = GHASH_BLOCK_SIZE - srclen;
124		while (srclen--)
125			*dst++ ^= *src++;
126	}
127
128	return 0;
129}
130
131static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
132{
133	u8 *dst = dctx->buffer;
134
135	if (dctx->bytes) {
136		u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
137
138		while (dctx->bytes--)
139			*tmp++ ^= 0;
140
141		kernel_fpu_begin();
142		clmul_ghash_mul(dst, &ctx->shash);
143		kernel_fpu_end();
144	}
145
146	dctx->bytes = 0;
147}
148
149static int ghash_final(struct shash_desc *desc, u8 *dst)
150{
151	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
152	struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
153	u8 *buf = dctx->buffer;
154
155	ghash_flush(ctx, dctx);
156	memcpy(dst, buf, GHASH_BLOCK_SIZE);
157
158	return 0;
159}
160
161static struct shash_alg ghash_alg = {
162	.digestsize	= GHASH_DIGEST_SIZE,
163	.init		= ghash_init,
164	.update		= ghash_update,
165	.final		= ghash_final,
166	.setkey		= ghash_setkey,
167	.descsize	= sizeof(struct ghash_desc_ctx),
168	.base		= {
169		.cra_name		= "__ghash",
170		.cra_driver_name	= "__ghash-pclmulqdqni",
171		.cra_priority		= 0,
172		.cra_flags		= CRYPTO_ALG_INTERNAL,
173		.cra_blocksize		= GHASH_BLOCK_SIZE,
174		.cra_ctxsize		= sizeof(struct ghash_ctx),
175		.cra_module		= THIS_MODULE,
176	},
177};
178
179static int ghash_async_init(struct ahash_request *req)
180{
181	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
182	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
183	struct ahash_request *cryptd_req = ahash_request_ctx(req);
184	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
185	struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
186	struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
187
188	desc->tfm = child;
189	return crypto_shash_init(desc);
190}
191
192static int ghash_async_update(struct ahash_request *req)
193{
194	struct ahash_request *cryptd_req = ahash_request_ctx(req);
195	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
196	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
197	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
198
199	if (!crypto_simd_usable() ||
200	    (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
201		memcpy(cryptd_req, req, sizeof(*req));
202		ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
203		return crypto_ahash_update(cryptd_req);
204	} else {
205		struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
206		return shash_ahash_update(req, desc);
207	}
208}
209
210static int ghash_async_final(struct ahash_request *req)
211{
212	struct ahash_request *cryptd_req = ahash_request_ctx(req);
213	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
214	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
215	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
216
217	if (!crypto_simd_usable() ||
218	    (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
219		memcpy(cryptd_req, req, sizeof(*req));
220		ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
221		return crypto_ahash_final(cryptd_req);
222	} else {
223		struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
224		return crypto_shash_final(desc, req->result);
225	}
226}
227
228static int ghash_async_import(struct ahash_request *req, const void *in)
229{
230	struct ahash_request *cryptd_req = ahash_request_ctx(req);
231	struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
232	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
233
234	ghash_async_init(req);
235	memcpy(dctx, in, sizeof(*dctx));
236	return 0;
237
238}
239
240static int ghash_async_export(struct ahash_request *req, void *out)
241{
242	struct ahash_request *cryptd_req = ahash_request_ctx(req);
243	struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
244	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
245
246	memcpy(out, dctx, sizeof(*dctx));
247	return 0;
248
249}
250
251static int ghash_async_digest(struct ahash_request *req)
252{
253	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
254	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
255	struct ahash_request *cryptd_req = ahash_request_ctx(req);
256	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
257
258	if (!crypto_simd_usable() ||
259	    (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
260		memcpy(cryptd_req, req, sizeof(*req));
261		ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
262		return crypto_ahash_digest(cryptd_req);
263	} else {
264		struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
265		struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
266
267		desc->tfm = child;
268		return shash_ahash_digest(req, desc);
269	}
270}
271
272static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
273			      unsigned int keylen)
274{
275	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
276	struct crypto_ahash *child = &ctx->cryptd_tfm->base;
277
278	crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
279	crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
280			       & CRYPTO_TFM_REQ_MASK);
281	return crypto_ahash_setkey(child, key, keylen);
282}
283
284static int ghash_async_init_tfm(struct crypto_tfm *tfm)
285{
286	struct cryptd_ahash *cryptd_tfm;
287	struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
288
289	cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni",
290					CRYPTO_ALG_INTERNAL,
291					CRYPTO_ALG_INTERNAL);
292	if (IS_ERR(cryptd_tfm))
293		return PTR_ERR(cryptd_tfm);
294	ctx->cryptd_tfm = cryptd_tfm;
295	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
296				 sizeof(struct ahash_request) +
297				 crypto_ahash_reqsize(&cryptd_tfm->base));
298
299	return 0;
300}
301
302static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
303{
304	struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
305
306	cryptd_free_ahash(ctx->cryptd_tfm);
307}
308
309static struct ahash_alg ghash_async_alg = {
310	.init		= ghash_async_init,
311	.update		= ghash_async_update,
312	.final		= ghash_async_final,
313	.setkey		= ghash_async_setkey,
314	.digest		= ghash_async_digest,
315	.export		= ghash_async_export,
316	.import		= ghash_async_import,
317	.halg = {
318		.digestsize	= GHASH_DIGEST_SIZE,
319		.statesize = sizeof(struct ghash_desc_ctx),
320		.base = {
321			.cra_name		= "ghash",
322			.cra_driver_name	= "ghash-clmulni",
323			.cra_priority		= 400,
324			.cra_ctxsize		= sizeof(struct ghash_async_ctx),
325			.cra_flags		= CRYPTO_ALG_ASYNC,
326			.cra_blocksize		= GHASH_BLOCK_SIZE,
327			.cra_module		= THIS_MODULE,
328			.cra_init		= ghash_async_init_tfm,
329			.cra_exit		= ghash_async_exit_tfm,
330		},
331	},
332};
333
334static const struct x86_cpu_id pcmul_cpu_id[] = {
335	X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL), /* Pickle-Mickle-Duck */
336	{}
337};
338MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
339
340static int __init ghash_pclmulqdqni_mod_init(void)
341{
342	int err;
343
344	if (!x86_match_cpu(pcmul_cpu_id))
345		return -ENODEV;
346
347	err = crypto_register_shash(&ghash_alg);
348	if (err)
349		goto err_out;
350	err = crypto_register_ahash(&ghash_async_alg);
351	if (err)
352		goto err_shash;
353
354	return 0;
355
356err_shash:
357	crypto_unregister_shash(&ghash_alg);
358err_out:
359	return err;
360}
361
362static void __exit ghash_pclmulqdqni_mod_exit(void)
363{
364	crypto_unregister_ahash(&ghash_async_alg);
365	crypto_unregister_shash(&ghash_alg);
366}
367
368module_init(ghash_pclmulqdqni_mod_init);
369module_exit(ghash_pclmulqdqni_mod_exit);
370
371MODULE_LICENSE("GPL");
372MODULE_DESCRIPTION("GHASH hash function, accelerated by PCLMULQDQ-NI");
373MODULE_ALIAS_CRYPTO("ghash");
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
  4 * instructions. This file contains glue code.
  5 *
  6 * Copyright (c) 2009 Intel Corp.
  7 *   Author: Huang Ying <ying.huang@intel.com>
  8 */
  9
 10#include <linux/err.h>
 11#include <linux/module.h>
 12#include <linux/init.h>
 13#include <linux/kernel.h>
 14#include <linux/crypto.h>
 15#include <crypto/algapi.h>
 16#include <crypto/cryptd.h>
 17#include <crypto/gf128mul.h>
 18#include <crypto/internal/hash.h>
 19#include <crypto/internal/simd.h>
 20#include <asm/cpu_device_id.h>
 21#include <asm/simd.h>
 
 22
 23#define GHASH_BLOCK_SIZE	16
 24#define GHASH_DIGEST_SIZE	16
 25
 26void clmul_ghash_mul(char *dst, const u128 *shash);
 27
 28void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
 29			const u128 *shash);
 30
 31struct ghash_async_ctx {
 32	struct cryptd_ahash *cryptd_tfm;
 33};
 34
 35struct ghash_ctx {
 36	u128 shash;
 37};
 38
 39struct ghash_desc_ctx {
 40	u8 buffer[GHASH_BLOCK_SIZE];
 41	u32 bytes;
 42};
 43
 44static int ghash_init(struct shash_desc *desc)
 45{
 46	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 47
 48	memset(dctx, 0, sizeof(*dctx));
 49
 50	return 0;
 51}
 52
 53static int ghash_setkey(struct crypto_shash *tfm,
 54			const u8 *key, unsigned int keylen)
 55{
 56	struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
 57	be128 *x = (be128 *)key;
 58	u64 a, b;
 59
 60	if (keylen != GHASH_BLOCK_SIZE)
 61		return -EINVAL;
 62
 63	/* perform multiplication by 'x' in GF(2^128) */
 64	a = be64_to_cpu(x->a);
 65	b = be64_to_cpu(x->b);
 66
 67	ctx->shash.a = (b << 1) | (a >> 63);
 68	ctx->shash.b = (a << 1) | (b >> 63);
 69
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 70	if (a >> 63)
 71		ctx->shash.b ^= ((u64)0xc2) << 56;
 72
 73	return 0;
 74}
 75
 76static int ghash_update(struct shash_desc *desc,
 77			 const u8 *src, unsigned int srclen)
 78{
 79	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
 80	struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
 81	u8 *dst = dctx->buffer;
 82
 83	kernel_fpu_begin();
 84	if (dctx->bytes) {
 85		int n = min(srclen, dctx->bytes);
 86		u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
 87
 88		dctx->bytes -= n;
 89		srclen -= n;
 90
 91		while (n--)
 92			*pos++ ^= *src++;
 93
 94		if (!dctx->bytes)
 95			clmul_ghash_mul(dst, &ctx->shash);
 96	}
 97
 98	clmul_ghash_update(dst, src, srclen, &ctx->shash);
 99	kernel_fpu_end();
100
101	if (srclen & 0xf) {
102		src += srclen - (srclen & 0xf);
103		srclen &= 0xf;
104		dctx->bytes = GHASH_BLOCK_SIZE - srclen;
105		while (srclen--)
106			*dst++ ^= *src++;
107	}
108
109	return 0;
110}
111
112static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
113{
114	u8 *dst = dctx->buffer;
115
116	if (dctx->bytes) {
117		u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
118
119		while (dctx->bytes--)
120			*tmp++ ^= 0;
121
122		kernel_fpu_begin();
123		clmul_ghash_mul(dst, &ctx->shash);
124		kernel_fpu_end();
125	}
126
127	dctx->bytes = 0;
128}
129
130static int ghash_final(struct shash_desc *desc, u8 *dst)
131{
132	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
133	struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
134	u8 *buf = dctx->buffer;
135
136	ghash_flush(ctx, dctx);
137	memcpy(dst, buf, GHASH_BLOCK_SIZE);
138
139	return 0;
140}
141
142static struct shash_alg ghash_alg = {
143	.digestsize	= GHASH_DIGEST_SIZE,
144	.init		= ghash_init,
145	.update		= ghash_update,
146	.final		= ghash_final,
147	.setkey		= ghash_setkey,
148	.descsize	= sizeof(struct ghash_desc_ctx),
149	.base		= {
150		.cra_name		= "__ghash",
151		.cra_driver_name	= "__ghash-pclmulqdqni",
152		.cra_priority		= 0,
153		.cra_flags		= CRYPTO_ALG_INTERNAL,
154		.cra_blocksize		= GHASH_BLOCK_SIZE,
155		.cra_ctxsize		= sizeof(struct ghash_ctx),
156		.cra_module		= THIS_MODULE,
157	},
158};
159
160static int ghash_async_init(struct ahash_request *req)
161{
162	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
163	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
164	struct ahash_request *cryptd_req = ahash_request_ctx(req);
165	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
166	struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
167	struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
168
169	desc->tfm = child;
170	return crypto_shash_init(desc);
171}
172
173static int ghash_async_update(struct ahash_request *req)
174{
175	struct ahash_request *cryptd_req = ahash_request_ctx(req);
176	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
177	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
178	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
179
180	if (!crypto_simd_usable() ||
181	    (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
182		memcpy(cryptd_req, req, sizeof(*req));
183		ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
184		return crypto_ahash_update(cryptd_req);
185	} else {
186		struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
187		return shash_ahash_update(req, desc);
188	}
189}
190
191static int ghash_async_final(struct ahash_request *req)
192{
193	struct ahash_request *cryptd_req = ahash_request_ctx(req);
194	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
195	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
196	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
197
198	if (!crypto_simd_usable() ||
199	    (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
200		memcpy(cryptd_req, req, sizeof(*req));
201		ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
202		return crypto_ahash_final(cryptd_req);
203	} else {
204		struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
205		return crypto_shash_final(desc, req->result);
206	}
207}
208
209static int ghash_async_import(struct ahash_request *req, const void *in)
210{
211	struct ahash_request *cryptd_req = ahash_request_ctx(req);
212	struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
213	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
214
215	ghash_async_init(req);
216	memcpy(dctx, in, sizeof(*dctx));
217	return 0;
218
219}
220
221static int ghash_async_export(struct ahash_request *req, void *out)
222{
223	struct ahash_request *cryptd_req = ahash_request_ctx(req);
224	struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
225	struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
226
227	memcpy(out, dctx, sizeof(*dctx));
228	return 0;
229
230}
231
232static int ghash_async_digest(struct ahash_request *req)
233{
234	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
235	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
236	struct ahash_request *cryptd_req = ahash_request_ctx(req);
237	struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
238
239	if (!crypto_simd_usable() ||
240	    (in_atomic() && cryptd_ahash_queued(cryptd_tfm))) {
241		memcpy(cryptd_req, req, sizeof(*req));
242		ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
243		return crypto_ahash_digest(cryptd_req);
244	} else {
245		struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
246		struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
247
248		desc->tfm = child;
249		return shash_ahash_digest(req, desc);
250	}
251}
252
253static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
254			      unsigned int keylen)
255{
256	struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
257	struct crypto_ahash *child = &ctx->cryptd_tfm->base;
258
259	crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
260	crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
261			       & CRYPTO_TFM_REQ_MASK);
262	return crypto_ahash_setkey(child, key, keylen);
263}
264
265static int ghash_async_init_tfm(struct crypto_tfm *tfm)
266{
267	struct cryptd_ahash *cryptd_tfm;
268	struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
269
270	cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni",
271					CRYPTO_ALG_INTERNAL,
272					CRYPTO_ALG_INTERNAL);
273	if (IS_ERR(cryptd_tfm))
274		return PTR_ERR(cryptd_tfm);
275	ctx->cryptd_tfm = cryptd_tfm;
276	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
277				 sizeof(struct ahash_request) +
278				 crypto_ahash_reqsize(&cryptd_tfm->base));
279
280	return 0;
281}
282
283static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
284{
285	struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
286
287	cryptd_free_ahash(ctx->cryptd_tfm);
288}
289
290static struct ahash_alg ghash_async_alg = {
291	.init		= ghash_async_init,
292	.update		= ghash_async_update,
293	.final		= ghash_async_final,
294	.setkey		= ghash_async_setkey,
295	.digest		= ghash_async_digest,
296	.export		= ghash_async_export,
297	.import		= ghash_async_import,
298	.halg = {
299		.digestsize	= GHASH_DIGEST_SIZE,
300		.statesize = sizeof(struct ghash_desc_ctx),
301		.base = {
302			.cra_name		= "ghash",
303			.cra_driver_name	= "ghash-clmulni",
304			.cra_priority		= 400,
305			.cra_ctxsize		= sizeof(struct ghash_async_ctx),
306			.cra_flags		= CRYPTO_ALG_ASYNC,
307			.cra_blocksize		= GHASH_BLOCK_SIZE,
308			.cra_module		= THIS_MODULE,
309			.cra_init		= ghash_async_init_tfm,
310			.cra_exit		= ghash_async_exit_tfm,
311		},
312	},
313};
314
315static const struct x86_cpu_id pcmul_cpu_id[] = {
316	X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL), /* Pickle-Mickle-Duck */
317	{}
318};
319MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
320
321static int __init ghash_pclmulqdqni_mod_init(void)
322{
323	int err;
324
325	if (!x86_match_cpu(pcmul_cpu_id))
326		return -ENODEV;
327
328	err = crypto_register_shash(&ghash_alg);
329	if (err)
330		goto err_out;
331	err = crypto_register_ahash(&ghash_async_alg);
332	if (err)
333		goto err_shash;
334
335	return 0;
336
337err_shash:
338	crypto_unregister_shash(&ghash_alg);
339err_out:
340	return err;
341}
342
343static void __exit ghash_pclmulqdqni_mod_exit(void)
344{
345	crypto_unregister_ahash(&ghash_async_alg);
346	crypto_unregister_shash(&ghash_alg);
347}
348
349module_init(ghash_pclmulqdqni_mod_init);
350module_exit(ghash_pclmulqdqni_mod_exit);
351
352MODULE_LICENSE("GPL");
353MODULE_DESCRIPTION("GHASH hash function, accelerated by PCLMULQDQ-NI");
354MODULE_ALIAS_CRYPTO("ghash");