xref: /linux/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.c (revision 68a052239fc4b351e961f698b824f7654a346091)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * sun8i-ce-cipher.c - hardware cryptographic offloader for
4  * Allwinner H3/A64/H5/H2+/H6/R40 SoC
5  *
6  * Copyright (C) 2016-2019 Corentin LABBE <clabbe.montjoie@gmail.com>
7  *
8  * This file add support for AES cipher with 128,192,256 bits keysize in
9  * CBC and ECB mode.
10  *
11  * You could find a link for the datasheet in Documentation/arch/arm/sunxi.rst
12  */
13 
14 #include <linux/bottom_half.h>
15 #include <linux/crypto.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/io.h>
18 #include <linux/pm_runtime.h>
19 #include <crypto/scatterwalk.h>
20 #include <crypto/internal/des.h>
21 #include <crypto/internal/skcipher.h>
22 #include "sun8i-ce.h"
23 
24 static int sun8i_ce_cipher_need_fallback(struct skcipher_request *areq)
25 {
26 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
27 	struct scatterlist *sg;
28 	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
29 	struct sun8i_ce_alg_template *algt;
30 	unsigned int todo, len;
31 
32 	algt = container_of(alg, struct sun8i_ce_alg_template, alg.skcipher.base);
33 
34 	if (sg_nents_for_len(areq->src, areq->cryptlen) > MAX_SG ||
35 	    sg_nents_for_len(areq->dst, areq->cryptlen) > MAX_SG) {
36 		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
37 			algt->stat_fb_maxsg++;
38 
39 		return true;
40 	}
41 
42 	if (areq->cryptlen < crypto_skcipher_ivsize(tfm)) {
43 		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
44 			algt->stat_fb_leniv++;
45 
46 		return true;
47 	}
48 
49 	if (areq->cryptlen == 0) {
50 		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
51 			algt->stat_fb_len0++;
52 
53 		return true;
54 	}
55 
56 	if (areq->cryptlen % 16) {
57 		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
58 			algt->stat_fb_mod16++;
59 
60 		return true;
61 	}
62 
63 	len = areq->cryptlen;
64 	sg = areq->src;
65 	while (sg) {
66 		if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
67 			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
68 				algt->stat_fb_srcali++;
69 
70 			return true;
71 		}
72 		todo = min(len, sg->length);
73 		if (todo % 4) {
74 			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
75 				algt->stat_fb_srclen++;
76 
77 			return true;
78 		}
79 		len -= todo;
80 		sg = sg_next(sg);
81 	}
82 
83 	len = areq->cryptlen;
84 	sg = areq->dst;
85 	while (sg) {
86 		if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
87 			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
88 				algt->stat_fb_dstali++;
89 
90 			return true;
91 		}
92 		todo = min(len, sg->length);
93 		if (todo % 4) {
94 			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
95 				algt->stat_fb_dstlen++;
96 
97 			return true;
98 		}
99 		len -= todo;
100 		sg = sg_next(sg);
101 	}
102 	return false;
103 }
104 
105 static int sun8i_ce_cipher_fallback(struct skcipher_request *areq)
106 {
107 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
108 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
109 	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
110 	int err;
111 
112 	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG)) {
113 		struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
114 		struct sun8i_ce_alg_template *algt;
115 
116 		algt = container_of(alg, struct sun8i_ce_alg_template,
117 				    alg.skcipher.base);
118 
119 		algt->stat_fb++;
120 	}
121 
122 	skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm);
123 	skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags,
124 				      areq->base.complete, areq->base.data);
125 	skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst,
126 				   areq->cryptlen, areq->iv);
127 	if (rctx->op_dir & CE_DECRYPTION)
128 		err = crypto_skcipher_decrypt(&rctx->fallback_req);
129 	else
130 		err = crypto_skcipher_encrypt(&rctx->fallback_req);
131 	return err;
132 }
133 
134 static int sun8i_ce_cipher_prepare(struct skcipher_request *areq,
135 				   struct ce_task *cet)
136 {
137 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
138 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
139 	struct sun8i_ce_dev *ce = op->ce;
140 	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
141 	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
142 	struct sun8i_ce_alg_template *algt;
143 	struct scatterlist *sg;
144 	unsigned int todo, len, offset, ivsize;
145 	u32 common, sym;
146 	int i;
147 	int nr_sgs = 0;
148 	int nr_sgd = 0;
149 	int err = 0;
150 	int ns = sg_nents_for_len(areq->src, areq->cryptlen);
151 	int nd = sg_nents_for_len(areq->dst, areq->cryptlen);
152 
153 	algt = container_of(alg, struct sun8i_ce_alg_template, alg.skcipher.base);
154 
155 	dev_dbg(ce->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__,
156 		crypto_tfm_alg_name(areq->base.tfm),
157 		areq->cryptlen,
158 		rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm),
159 		op->keylen);
160 
161 	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
162 		algt->stat_req++;
163 
164 	memset(cet, 0, sizeof(struct ce_task));
165 
166 	cet->t_id = cpu_to_le32(rctx->flow);
167 	common = ce->variant->alg_cipher[algt->ce_algo_id];
168 	common |= rctx->op_dir | CE_COMM_INT;
169 	cet->t_common_ctl = cpu_to_le32(common);
170 	/* CTS and recent CE (H6) need length in bytes, in word otherwise */
171 	if (ce->variant->cipher_t_dlen_in_bytes)
172 		cet->t_dlen = cpu_to_le32(areq->cryptlen);
173 	else
174 		cet->t_dlen = cpu_to_le32(areq->cryptlen / 4);
175 
176 	sym = ce->variant->op_mode[algt->ce_blockmode];
177 	len = op->keylen;
178 	switch (len) {
179 	case 128 / 8:
180 		sym |= CE_AES_128BITS;
181 		break;
182 	case 192 / 8:
183 		sym |= CE_AES_192BITS;
184 		break;
185 	case 256 / 8:
186 		sym |= CE_AES_256BITS;
187 		break;
188 	}
189 
190 	cet->t_sym_ctl = cpu_to_le32(sym);
191 	cet->t_asym_ctl = 0;
192 
193 	rctx->addr_key = dma_map_single(ce->dev, op->key, op->keylen, DMA_TO_DEVICE);
194 	if (dma_mapping_error(ce->dev, rctx->addr_key)) {
195 		dev_err(ce->dev, "Cannot DMA MAP KEY\n");
196 		err = -EFAULT;
197 		goto theend;
198 	}
199 	cet->t_key = desc_addr_val_le32(ce, rctx->addr_key);
200 
201 	ivsize = crypto_skcipher_ivsize(tfm);
202 	if (areq->iv && ivsize > 0) {
203 		if (rctx->op_dir & CE_DECRYPTION) {
204 			offset = areq->cryptlen - ivsize;
205 			scatterwalk_map_and_copy(rctx->backup_iv, areq->src,
206 						 offset, ivsize, 0);
207 		}
208 		memcpy(rctx->bounce_iv, areq->iv, ivsize);
209 		rctx->addr_iv = dma_map_single(ce->dev, rctx->bounce_iv, ivsize,
210 					       DMA_TO_DEVICE);
211 		if (dma_mapping_error(ce->dev, rctx->addr_iv)) {
212 			dev_err(ce->dev, "Cannot DMA MAP IV\n");
213 			err = -ENOMEM;
214 			goto theend_iv;
215 		}
216 		cet->t_iv = desc_addr_val_le32(ce, rctx->addr_iv);
217 	}
218 
219 	if (areq->src == areq->dst) {
220 		nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_BIDIRECTIONAL);
221 		if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
222 			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
223 			err = -EINVAL;
224 			goto theend_iv;
225 		}
226 		nr_sgd = nr_sgs;
227 	} else {
228 		nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
229 		if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
230 			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
231 			err = -EINVAL;
232 			goto theend_iv;
233 		}
234 		nr_sgd = dma_map_sg(ce->dev, areq->dst, nd, DMA_FROM_DEVICE);
235 		if (nr_sgd <= 0 || nr_sgd > MAX_SG) {
236 			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgd);
237 			err = -EINVAL;
238 			goto theend_sgs;
239 		}
240 	}
241 
242 	len = areq->cryptlen;
243 	for_each_sg(areq->src, sg, nr_sgs, i) {
244 		cet->t_src[i].addr = desc_addr_val_le32(ce, sg_dma_address(sg));
245 		todo = min(len, sg_dma_len(sg));
246 		cet->t_src[i].len = cpu_to_le32(todo / 4);
247 		dev_dbg(ce->dev, "%s total=%u SG(%d %u off=%d) todo=%u\n", __func__,
248 			areq->cryptlen, i, cet->t_src[i].len, sg->offset, todo);
249 		len -= todo;
250 	}
251 	if (len > 0) {
252 		dev_err(ce->dev, "remaining len %d\n", len);
253 		err = -EINVAL;
254 		goto theend_sgs;
255 	}
256 
257 	len = areq->cryptlen;
258 	for_each_sg(areq->dst, sg, nr_sgd, i) {
259 		cet->t_dst[i].addr = desc_addr_val_le32(ce, sg_dma_address(sg));
260 		todo = min(len, sg_dma_len(sg));
261 		cet->t_dst[i].len = cpu_to_le32(todo / 4);
262 		dev_dbg(ce->dev, "%s total=%u SG(%d %u off=%d) todo=%u\n", __func__,
263 			areq->cryptlen, i, cet->t_dst[i].len, sg->offset, todo);
264 		len -= todo;
265 	}
266 	if (len > 0) {
267 		dev_err(ce->dev, "remaining len %d\n", len);
268 		err = -EINVAL;
269 		goto theend_sgs;
270 	}
271 
272 	rctx->nr_sgs = ns;
273 	rctx->nr_sgd = nd;
274 	return 0;
275 
276 theend_sgs:
277 	if (areq->src == areq->dst) {
278 		dma_unmap_sg(ce->dev, areq->src, ns, DMA_BIDIRECTIONAL);
279 	} else {
280 		if (nr_sgs > 0)
281 			dma_unmap_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
282 
283 		if (nr_sgd > 0)
284 			dma_unmap_sg(ce->dev, areq->dst, nd, DMA_FROM_DEVICE);
285 	}
286 
287 theend_iv:
288 	if (areq->iv && ivsize > 0) {
289 		if (!dma_mapping_error(ce->dev, rctx->addr_iv))
290 			dma_unmap_single(ce->dev, rctx->addr_iv, ivsize,
291 					 DMA_TO_DEVICE);
292 
293 		offset = areq->cryptlen - ivsize;
294 		if (rctx->op_dir & CE_DECRYPTION) {
295 			memcpy(areq->iv, rctx->backup_iv, ivsize);
296 			memzero_explicit(rctx->backup_iv, ivsize);
297 		} else {
298 			scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
299 						 ivsize, 0);
300 		}
301 		memzero_explicit(rctx->bounce_iv, ivsize);
302 	}
303 
304 	dma_unmap_single(ce->dev, rctx->addr_key, op->keylen, DMA_TO_DEVICE);
305 
306 theend:
307 	return err;
308 }
309 
310 static void sun8i_ce_cipher_unprepare(struct skcipher_request *areq,
311 				      struct ce_task *cet)
312 {
313 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
314 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
315 	struct sun8i_ce_dev *ce = op->ce;
316 	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
317 	unsigned int ivsize, offset;
318 	int nr_sgs = rctx->nr_sgs;
319 	int nr_sgd = rctx->nr_sgd;
320 
321 	ivsize = crypto_skcipher_ivsize(tfm);
322 
323 	if (areq->src == areq->dst) {
324 		dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
325 	} else {
326 		if (nr_sgs > 0)
327 			dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
328 		dma_unmap_sg(ce->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
329 	}
330 
331 	if (areq->iv && ivsize > 0) {
332 		if (cet->t_iv)
333 			dma_unmap_single(ce->dev, rctx->addr_iv, ivsize,
334 					 DMA_TO_DEVICE);
335 		offset = areq->cryptlen - ivsize;
336 		if (rctx->op_dir & CE_DECRYPTION) {
337 			memcpy(areq->iv, rctx->backup_iv, ivsize);
338 			memzero_explicit(rctx->backup_iv, ivsize);
339 		} else {
340 			scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
341 						 ivsize, 0);
342 		}
343 		memzero_explicit(rctx->bounce_iv, ivsize);
344 	}
345 
346 	dma_unmap_single(ce->dev, rctx->addr_key, op->keylen, DMA_TO_DEVICE);
347 }
348 
349 int sun8i_ce_cipher_do_one(struct crypto_engine *engine, void *areq)
350 {
351 	struct skcipher_request *req = skcipher_request_cast(areq);
352 	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(req);
353 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
354 	struct sun8i_cipher_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
355 	struct sun8i_ce_dev *ce = ctx->ce;
356 	struct sun8i_ce_flow *chan;
357 	int err;
358 
359 	chan = &ce->chanlist[rctx->flow];
360 
361 	err = sun8i_ce_cipher_prepare(req, chan->tl);
362 	if (err)
363 		return err;
364 
365 	err = sun8i_ce_run_task(ce, rctx->flow,
366 				crypto_tfm_alg_name(req->base.tfm));
367 
368 	sun8i_ce_cipher_unprepare(req, chan->tl);
369 
370 	local_bh_disable();
371 	crypto_finalize_skcipher_request(engine, req, err);
372 	local_bh_enable();
373 
374 	return 0;
375 }
376 
377 int sun8i_ce_skdecrypt(struct skcipher_request *areq)
378 {
379 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
380 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
381 	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
382 	struct crypto_engine *engine;
383 	int e;
384 
385 	rctx->op_dir = CE_DECRYPTION;
386 	if (sun8i_ce_cipher_need_fallback(areq))
387 		return sun8i_ce_cipher_fallback(areq);
388 
389 	e = sun8i_ce_get_engine_number(op->ce);
390 	rctx->flow = e;
391 	engine = op->ce->chanlist[e].engine;
392 
393 	return crypto_transfer_skcipher_request_to_engine(engine, areq);
394 }
395 
396 int sun8i_ce_skencrypt(struct skcipher_request *areq)
397 {
398 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
399 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
400 	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
401 	struct crypto_engine *engine;
402 	int e;
403 
404 	rctx->op_dir = CE_ENCRYPTION;
405 	if (sun8i_ce_cipher_need_fallback(areq))
406 		return sun8i_ce_cipher_fallback(areq);
407 
408 	e = sun8i_ce_get_engine_number(op->ce);
409 	rctx->flow = e;
410 	engine = op->ce->chanlist[e].engine;
411 
412 	return crypto_transfer_skcipher_request_to_engine(engine, areq);
413 }
414 
415 int sun8i_ce_cipher_init(struct crypto_tfm *tfm)
416 {
417 	struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
418 	struct sun8i_ce_alg_template *algt;
419 	const char *name = crypto_tfm_alg_name(tfm);
420 	struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm);
421 	struct skcipher_alg *alg = crypto_skcipher_alg(sktfm);
422 	int err;
423 
424 	memset(op, 0, sizeof(struct sun8i_cipher_tfm_ctx));
425 
426 	algt = container_of(alg, struct sun8i_ce_alg_template, alg.skcipher.base);
427 	op->ce = algt->ce;
428 
429 	op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
430 	if (IS_ERR(op->fallback_tfm)) {
431 		dev_err(op->ce->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
432 			name, PTR_ERR(op->fallback_tfm));
433 		return PTR_ERR(op->fallback_tfm);
434 	}
435 
436 	crypto_skcipher_set_reqsize(sktfm, sizeof(struct sun8i_cipher_req_ctx) +
437 				    crypto_skcipher_reqsize(op->fallback_tfm));
438 
439 	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
440 		memcpy(algt->fbname,
441 		       crypto_skcipher_driver_name(op->fallback_tfm),
442 		       CRYPTO_MAX_ALG_NAME);
443 
444 	err = pm_runtime_resume_and_get(op->ce->dev);
445 	if (err < 0)
446 		goto error_pm;
447 
448 	return 0;
449 error_pm:
450 	crypto_free_skcipher(op->fallback_tfm);
451 	return err;
452 }
453 
454 void sun8i_ce_cipher_exit(struct crypto_tfm *tfm)
455 {
456 	struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
457 
458 	kfree_sensitive(op->key);
459 	crypto_free_skcipher(op->fallback_tfm);
460 	pm_runtime_put_sync_suspend(op->ce->dev);
461 }
462 
463 int sun8i_ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
464 			unsigned int keylen)
465 {
466 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
467 	struct sun8i_ce_dev *ce = op->ce;
468 
469 	switch (keylen) {
470 	case 128 / 8:
471 		break;
472 	case 192 / 8:
473 		break;
474 	case 256 / 8:
475 		break;
476 	default:
477 		dev_dbg(ce->dev, "ERROR: Invalid keylen %u\n", keylen);
478 		return -EINVAL;
479 	}
480 	kfree_sensitive(op->key);
481 	op->keylen = keylen;
482 	op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
483 	if (!op->key)
484 		return -ENOMEM;
485 
486 	crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
487 	crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
488 
489 	return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
490 }
491 
492 int sun8i_ce_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
493 			 unsigned int keylen)
494 {
495 	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
496 	int err;
497 
498 	err = verify_skcipher_des3_key(tfm, key);
499 	if (err)
500 		return err;
501 
502 	kfree_sensitive(op->key);
503 	op->keylen = keylen;
504 	op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
505 	if (!op->key)
506 		return -ENOMEM;
507 
508 	crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
509 	crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
510 
511 	return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
512 }
513