sun8i-ce-cipher.c

  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
 24static 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
105static 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
134static 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
276theend_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
287theend_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
306theend:
307	return err;
308}
309
310static 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
349int 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
377int 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
396int 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
415int 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;
449error_pm:
450	crypto_free_skcipher(op->fallback_tfm);
451	return err;
452}
453
454void 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
463int 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
492int 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}