1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * sun8i-ss-cipher.c - hardware cryptographic offloader for
4 * Allwinner A80/A83T 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/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/skcipher.h>
21 #include "sun8i-ss.h"
22
sun8i_ss_need_fallback(struct skcipher_request * areq)23 static bool sun8i_ss_need_fallback(struct skcipher_request *areq)
24 {
25 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
26 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
27 struct sun8i_ss_alg_template *algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
28 struct scatterlist *in_sg = areq->src;
29 struct scatterlist *out_sg = areq->dst;
30 struct scatterlist *sg;
31 unsigned int todo, len;
32
33 if (areq->cryptlen == 0 || areq->cryptlen % 16) {
34 algt->stat_fb_len++;
35 return true;
36 }
37
38 if (sg_nents_for_len(areq->src, areq->cryptlen) > 8 ||
39 sg_nents_for_len(areq->dst, areq->cryptlen) > 8) {
40 algt->stat_fb_sgnum++;
41 return true;
42 }
43
44 len = areq->cryptlen;
45 sg = areq->src;
46 while (sg) {
47 todo = min(len, sg->length);
48 if ((todo % 16) != 0) {
49 algt->stat_fb_sglen++;
50 return true;
51 }
52 if (!IS_ALIGNED(sg->offset, 16)) {
53 algt->stat_fb_align++;
54 return true;
55 }
56 len -= todo;
57 sg = sg_next(sg);
58 }
59 len = areq->cryptlen;
60 sg = areq->dst;
61 while (sg) {
62 todo = min(len, sg->length);
63 if ((todo % 16) != 0) {
64 algt->stat_fb_sglen++;
65 return true;
66 }
67 if (!IS_ALIGNED(sg->offset, 16)) {
68 algt->stat_fb_align++;
69 return true;
70 }
71 len -= todo;
72 sg = sg_next(sg);
73 }
74
75 /* SS need same numbers of SG (with same length) for source and destination */
76 in_sg = areq->src;
77 out_sg = areq->dst;
78 while (in_sg && out_sg) {
79 if (in_sg->length != out_sg->length)
80 return true;
81 in_sg = sg_next(in_sg);
82 out_sg = sg_next(out_sg);
83 }
84 if (in_sg || out_sg)
85 return true;
86 return false;
87 }
88
sun8i_ss_cipher_fallback(struct skcipher_request * areq)89 static int sun8i_ss_cipher_fallback(struct skcipher_request *areq)
90 {
91 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
92 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
93 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
94 int err;
95
96 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
97 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
98 struct sun8i_ss_alg_template *algt;
99
100 algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
101 algt->stat_fb++;
102 #endif
103 skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm);
104 skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags,
105 areq->base.complete, areq->base.data);
106 skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst,
107 areq->cryptlen, areq->iv);
108 if (rctx->op_dir & SS_DECRYPTION)
109 err = crypto_skcipher_decrypt(&rctx->fallback_req);
110 else
111 err = crypto_skcipher_encrypt(&rctx->fallback_req);
112 return err;
113 }
114
sun8i_ss_setup_ivs(struct skcipher_request * areq)115 static int sun8i_ss_setup_ivs(struct skcipher_request *areq)
116 {
117 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
118 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
119 struct sun8i_ss_dev *ss = op->ss;
120 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
121 struct scatterlist *sg = areq->src;
122 unsigned int todo, offset;
123 unsigned int len = areq->cryptlen;
124 unsigned int ivsize = crypto_skcipher_ivsize(tfm);
125 struct sun8i_ss_flow *sf = &ss->flows[rctx->flow];
126 int i = 0;
127 dma_addr_t a;
128 int err;
129
130 rctx->ivlen = ivsize;
131 if (rctx->op_dir & SS_DECRYPTION) {
132 offset = areq->cryptlen - ivsize;
133 scatterwalk_map_and_copy(sf->biv, areq->src, offset,
134 ivsize, 0);
135 }
136
137 /* we need to copy all IVs from source in case DMA is bi-directionnal */
138 while (sg && len) {
139 if (sg_dma_len(sg) == 0) {
140 sg = sg_next(sg);
141 continue;
142 }
143 if (i == 0)
144 memcpy(sf->iv[0], areq->iv, ivsize);
145 a = dma_map_single(ss->dev, sf->iv[i], ivsize, DMA_TO_DEVICE);
146 if (dma_mapping_error(ss->dev, a)) {
147 memzero_explicit(sf->iv[i], ivsize);
148 dev_err(ss->dev, "Cannot DMA MAP IV\n");
149 err = -EFAULT;
150 goto dma_iv_error;
151 }
152 rctx->p_iv[i] = a;
153 /* we need to setup all others IVs only in the decrypt way */
154 if (rctx->op_dir == SS_ENCRYPTION)
155 return 0;
156 todo = min(len, sg_dma_len(sg));
157 len -= todo;
158 i++;
159 if (i < MAX_SG) {
160 offset = sg->length - ivsize;
161 scatterwalk_map_and_copy(sf->iv[i], sg, offset, ivsize, 0);
162 }
163 rctx->niv = i;
164 sg = sg_next(sg);
165 }
166
167 return 0;
168 dma_iv_error:
169 i--;
170 while (i >= 0) {
171 dma_unmap_single(ss->dev, rctx->p_iv[i], ivsize, DMA_TO_DEVICE);
172 memzero_explicit(sf->iv[i], ivsize);
173 i--;
174 }
175 return err;
176 }
177
sun8i_ss_cipher(struct skcipher_request * areq)178 static int sun8i_ss_cipher(struct skcipher_request *areq)
179 {
180 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
181 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
182 struct sun8i_ss_dev *ss = op->ss;
183 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
184 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
185 struct sun8i_ss_alg_template *algt;
186 struct sun8i_ss_flow *sf = &ss->flows[rctx->flow];
187 struct scatterlist *sg;
188 unsigned int todo, len, offset, ivsize;
189 int nr_sgs = 0;
190 int nr_sgd = 0;
191 int err = 0;
192 int nsgs = sg_nents_for_len(areq->src, areq->cryptlen);
193 int nsgd = sg_nents_for_len(areq->dst, areq->cryptlen);
194 int i;
195
196 algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
197
198 dev_dbg(ss->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__,
199 crypto_tfm_alg_name(areq->base.tfm),
200 areq->cryptlen,
201 rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm),
202 op->keylen);
203
204 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
205 algt->stat_req++;
206 #endif
207
208 rctx->op_mode = ss->variant->op_mode[algt->ss_blockmode];
209 rctx->method = ss->variant->alg_cipher[algt->ss_algo_id];
210 rctx->keylen = op->keylen;
211
212 rctx->p_key = dma_map_single(ss->dev, op->key, op->keylen, DMA_TO_DEVICE);
213 if (dma_mapping_error(ss->dev, rctx->p_key)) {
214 dev_err(ss->dev, "Cannot DMA MAP KEY\n");
215 err = -EFAULT;
216 goto theend;
217 }
218
219 ivsize = crypto_skcipher_ivsize(tfm);
220 if (areq->iv && crypto_skcipher_ivsize(tfm) > 0) {
221 err = sun8i_ss_setup_ivs(areq);
222 if (err)
223 goto theend_key;
224 }
225 if (areq->src == areq->dst) {
226 nr_sgs = dma_map_sg(ss->dev, areq->src, nsgs, DMA_BIDIRECTIONAL);
227 if (nr_sgs <= 0 || nr_sgs > 8) {
228 dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
229 err = -EINVAL;
230 goto theend_iv;
231 }
232 nr_sgd = nr_sgs;
233 } else {
234 nr_sgs = dma_map_sg(ss->dev, areq->src, nsgs, DMA_TO_DEVICE);
235 if (nr_sgs <= 0 || nr_sgs > 8) {
236 dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs);
237 err = -EINVAL;
238 goto theend_iv;
239 }
240 nr_sgd = dma_map_sg(ss->dev, areq->dst, nsgd, DMA_FROM_DEVICE);
241 if (nr_sgd <= 0 || nr_sgd > 8) {
242 dev_err(ss->dev, "Invalid sg number %d\n", nr_sgd);
243 err = -EINVAL;
244 goto theend_sgs;
245 }
246 }
247
248 len = areq->cryptlen;
249 i = 0;
250 sg = areq->src;
251 while (i < nr_sgs && sg && len) {
252 if (sg_dma_len(sg) == 0)
253 goto sgs_next;
254 rctx->t_src[i].addr = sg_dma_address(sg);
255 todo = min(len, sg_dma_len(sg));
256 rctx->t_src[i].len = todo / 4;
257 dev_dbg(ss->dev, "%s total=%u SGS(%d %u off=%d) todo=%u\n", __func__,
258 areq->cryptlen, i, rctx->t_src[i].len, sg->offset, todo);
259 len -= todo;
260 i++;
261 sgs_next:
262 sg = sg_next(sg);
263 }
264 if (len > 0) {
265 dev_err(ss->dev, "remaining len %d\n", len);
266 err = -EINVAL;
267 goto theend_sgs;
268 }
269
270 len = areq->cryptlen;
271 i = 0;
272 sg = areq->dst;
273 while (i < nr_sgd && sg && len) {
274 if (sg_dma_len(sg) == 0)
275 goto sgd_next;
276 rctx->t_dst[i].addr = sg_dma_address(sg);
277 todo = min(len, sg_dma_len(sg));
278 rctx->t_dst[i].len = todo / 4;
279 dev_dbg(ss->dev, "%s total=%u SGD(%d %u off=%d) todo=%u\n", __func__,
280 areq->cryptlen, i, rctx->t_dst[i].len, sg->offset, todo);
281 len -= todo;
282 i++;
283 sgd_next:
284 sg = sg_next(sg);
285 }
286 if (len > 0) {
287 dev_err(ss->dev, "remaining len %d\n", len);
288 err = -EINVAL;
289 goto theend_sgs;
290 }
291
292 err = sun8i_ss_run_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm));
293
294 theend_sgs:
295 if (areq->src == areq->dst) {
296 dma_unmap_sg(ss->dev, areq->src, nsgs, DMA_BIDIRECTIONAL);
297 } else {
298 dma_unmap_sg(ss->dev, areq->src, nsgs, DMA_TO_DEVICE);
299 dma_unmap_sg(ss->dev, areq->dst, nsgd, DMA_FROM_DEVICE);
300 }
301
302 theend_iv:
303 if (areq->iv && ivsize > 0) {
304 for (i = 0; i < rctx->niv; i++) {
305 dma_unmap_single(ss->dev, rctx->p_iv[i], ivsize, DMA_TO_DEVICE);
306 memzero_explicit(sf->iv[i], ivsize);
307 }
308
309 offset = areq->cryptlen - ivsize;
310 if (rctx->op_dir & SS_DECRYPTION) {
311 memcpy(areq->iv, sf->biv, ivsize);
312 memzero_explicit(sf->biv, ivsize);
313 } else {
314 scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
315 ivsize, 0);
316 }
317 }
318
319 theend_key:
320 dma_unmap_single(ss->dev, rctx->p_key, op->keylen, DMA_TO_DEVICE);
321
322 theend:
323
324 return err;
325 }
326
sun8i_ss_handle_cipher_request(struct crypto_engine * engine,void * areq)327 static int sun8i_ss_handle_cipher_request(struct crypto_engine *engine, void *areq)
328 {
329 int err;
330 struct skcipher_request *breq = container_of(areq, struct skcipher_request, base);
331
332 err = sun8i_ss_cipher(breq);
333 local_bh_disable();
334 crypto_finalize_skcipher_request(engine, breq, err);
335 local_bh_enable();
336
337 return 0;
338 }
339
sun8i_ss_skdecrypt(struct skcipher_request * areq)340 int sun8i_ss_skdecrypt(struct skcipher_request *areq)
341 {
342 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
343 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
344 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
345 struct crypto_engine *engine;
346 int e;
347
348 memset(rctx, 0, sizeof(struct sun8i_cipher_req_ctx));
349 rctx->op_dir = SS_DECRYPTION;
350
351 if (sun8i_ss_need_fallback(areq))
352 return sun8i_ss_cipher_fallback(areq);
353
354 e = sun8i_ss_get_engine_number(op->ss);
355 engine = op->ss->flows[e].engine;
356 rctx->flow = e;
357
358 return crypto_transfer_skcipher_request_to_engine(engine, areq);
359 }
360
sun8i_ss_skencrypt(struct skcipher_request * areq)361 int sun8i_ss_skencrypt(struct skcipher_request *areq)
362 {
363 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
364 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
365 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
366 struct crypto_engine *engine;
367 int e;
368
369 memset(rctx, 0, sizeof(struct sun8i_cipher_req_ctx));
370 rctx->op_dir = SS_ENCRYPTION;
371
372 if (sun8i_ss_need_fallback(areq))
373 return sun8i_ss_cipher_fallback(areq);
374
375 e = sun8i_ss_get_engine_number(op->ss);
376 engine = op->ss->flows[e].engine;
377 rctx->flow = e;
378
379 return crypto_transfer_skcipher_request_to_engine(engine, areq);
380 }
381
sun8i_ss_cipher_init(struct crypto_tfm * tfm)382 int sun8i_ss_cipher_init(struct crypto_tfm *tfm)
383 {
384 struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
385 struct sun8i_ss_alg_template *algt;
386 const char *name = crypto_tfm_alg_name(tfm);
387 struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm);
388 struct skcipher_alg *alg = crypto_skcipher_alg(sktfm);
389 int err;
390
391 memset(op, 0, sizeof(struct sun8i_cipher_tfm_ctx));
392
393 algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher);
394 op->ss = algt->ss;
395
396 op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
397 if (IS_ERR(op->fallback_tfm)) {
398 dev_err(op->ss->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
399 name, PTR_ERR(op->fallback_tfm));
400 return PTR_ERR(op->fallback_tfm);
401 }
402
403 sktfm->reqsize = sizeof(struct sun8i_cipher_req_ctx) +
404 crypto_skcipher_reqsize(op->fallback_tfm);
405
406
407 memcpy(algt->fbname,
408 crypto_tfm_alg_driver_name(crypto_skcipher_tfm(op->fallback_tfm)),
409 CRYPTO_MAX_ALG_NAME);
410
411 op->enginectx.op.do_one_request = sun8i_ss_handle_cipher_request;
412 op->enginectx.op.prepare_request = NULL;
413 op->enginectx.op.unprepare_request = NULL;
414
415 err = pm_runtime_resume_and_get(op->ss->dev);
416 if (err < 0) {
417 dev_err(op->ss->dev, "pm error %d\n", err);
418 goto error_pm;
419 }
420
421 return 0;
422 error_pm:
423 crypto_free_skcipher(op->fallback_tfm);
424 return err;
425 }
426
sun8i_ss_cipher_exit(struct crypto_tfm * tfm)427 void sun8i_ss_cipher_exit(struct crypto_tfm *tfm)
428 {
429 struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
430
431 kfree_sensitive(op->key);
432 crypto_free_skcipher(op->fallback_tfm);
433 pm_runtime_put_sync(op->ss->dev);
434 }
435
sun8i_ss_aes_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)436 int sun8i_ss_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
437 unsigned int keylen)
438 {
439 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
440 struct sun8i_ss_dev *ss = op->ss;
441
442 switch (keylen) {
443 case 128 / 8:
444 break;
445 case 192 / 8:
446 break;
447 case 256 / 8:
448 break;
449 default:
450 dev_dbg(ss->dev, "ERROR: Invalid keylen %u\n", keylen);
451 return -EINVAL;
452 }
453 kfree_sensitive(op->key);
454 op->keylen = keylen;
455 op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
456 if (!op->key)
457 return -ENOMEM;
458
459 crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
460 crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
461
462 return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
463 }
464
sun8i_ss_des3_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)465 int sun8i_ss_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
466 unsigned int keylen)
467 {
468 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
469 struct sun8i_ss_dev *ss = op->ss;
470
471 if (unlikely(keylen != 3 * DES_KEY_SIZE)) {
472 dev_dbg(ss->dev, "Invalid keylen %u\n", keylen);
473 return -EINVAL;
474 }
475
476 kfree_sensitive(op->key);
477 op->keylen = keylen;
478 op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
479 if (!op->key)
480 return -ENOMEM;
481
482 crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
483 crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
484
485 return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
486 }
487