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

source code of linux/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-cipher.c