xref: /openbmc/linux/drivers/crypto/caam/caampkc.c (revision fb8d6c8d)
1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
2 /*
3  * caam - Freescale FSL CAAM support for Public Key Cryptography
4  *
5  * Copyright 2016 Freescale Semiconductor, Inc.
6  * Copyright 2018-2019 NXP
7  *
8  * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
9  * all the desired key parameters, input and output pointers.
10  */
11 #include "compat.h"
12 #include "regs.h"
13 #include "intern.h"
14 #include "jr.h"
15 #include "error.h"
16 #include "desc_constr.h"
17 #include "sg_sw_sec4.h"
18 #include "caampkc.h"
19 
20 #define DESC_RSA_PUB_LEN	(2 * CAAM_CMD_SZ + SIZEOF_RSA_PUB_PDB)
21 #define DESC_RSA_PRIV_F1_LEN	(2 * CAAM_CMD_SZ + \
22 				 SIZEOF_RSA_PRIV_F1_PDB)
23 #define DESC_RSA_PRIV_F2_LEN	(2 * CAAM_CMD_SZ + \
24 				 SIZEOF_RSA_PRIV_F2_PDB)
25 #define DESC_RSA_PRIV_F3_LEN	(2 * CAAM_CMD_SZ + \
26 				 SIZEOF_RSA_PRIV_F3_PDB)
27 #define CAAM_RSA_MAX_INPUT_SIZE	512 /* for a 4096-bit modulus */
28 
29 /* buffer filled with zeros, used for padding */
30 static u8 *zero_buffer;
31 
32 /*
33  * variable used to avoid double free of resources in case
34  * algorithm registration was unsuccessful
35  */
36 static bool init_done;
37 
38 struct caam_akcipher_alg {
39 	struct akcipher_alg akcipher;
40 	bool registered;
41 };
42 
43 static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
44 			 struct akcipher_request *req)
45 {
46 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
47 
48 	dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
49 	dma_unmap_sg(dev, req_ctx->fixup_src, edesc->src_nents, DMA_TO_DEVICE);
50 
51 	if (edesc->sec4_sg_bytes)
52 		dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
53 				 DMA_TO_DEVICE);
54 }
55 
56 static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
57 			  struct akcipher_request *req)
58 {
59 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
60 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
61 	struct caam_rsa_key *key = &ctx->key;
62 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
63 
64 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
65 	dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
66 }
67 
68 static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
69 			      struct akcipher_request *req)
70 {
71 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
72 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
73 	struct caam_rsa_key *key = &ctx->key;
74 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
75 
76 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
77 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
78 }
79 
80 static void rsa_priv_f2_unmap(struct device *dev, struct rsa_edesc *edesc,
81 			      struct akcipher_request *req)
82 {
83 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
84 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
85 	struct caam_rsa_key *key = &ctx->key;
86 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
87 	size_t p_sz = key->p_sz;
88 	size_t q_sz = key->q_sz;
89 
90 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
91 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
92 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
93 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
94 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
95 }
96 
97 static void rsa_priv_f3_unmap(struct device *dev, struct rsa_edesc *edesc,
98 			      struct akcipher_request *req)
99 {
100 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
101 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
102 	struct caam_rsa_key *key = &ctx->key;
103 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
104 	size_t p_sz = key->p_sz;
105 	size_t q_sz = key->q_sz;
106 
107 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
108 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
109 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
110 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
111 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
112 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
113 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
114 }
115 
116 /* RSA Job Completion handler */
117 static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
118 {
119 	struct akcipher_request *req = context;
120 	struct rsa_edesc *edesc;
121 	int ecode = 0;
122 
123 	if (err)
124 		ecode = caam_jr_strstatus(dev, err);
125 
126 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
127 
128 	rsa_pub_unmap(dev, edesc, req);
129 	rsa_io_unmap(dev, edesc, req);
130 	kfree(edesc);
131 
132 	akcipher_request_complete(req, ecode);
133 }
134 
135 static void rsa_priv_f1_done(struct device *dev, u32 *desc, u32 err,
136 			     void *context)
137 {
138 	struct akcipher_request *req = context;
139 	struct rsa_edesc *edesc;
140 	int ecode = 0;
141 
142 	if (err)
143 		ecode = caam_jr_strstatus(dev, err);
144 
145 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
146 
147 	rsa_priv_f1_unmap(dev, edesc, req);
148 	rsa_io_unmap(dev, edesc, req);
149 	kfree(edesc);
150 
151 	akcipher_request_complete(req, ecode);
152 }
153 
154 static void rsa_priv_f2_done(struct device *dev, u32 *desc, u32 err,
155 			     void *context)
156 {
157 	struct akcipher_request *req = context;
158 	struct rsa_edesc *edesc;
159 	int ecode = 0;
160 
161 	if (err)
162 		ecode = caam_jr_strstatus(dev, err);
163 
164 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
165 
166 	rsa_priv_f2_unmap(dev, edesc, req);
167 	rsa_io_unmap(dev, edesc, req);
168 	kfree(edesc);
169 
170 	akcipher_request_complete(req, ecode);
171 }
172 
173 static void rsa_priv_f3_done(struct device *dev, u32 *desc, u32 err,
174 			     void *context)
175 {
176 	struct akcipher_request *req = context;
177 	struct rsa_edesc *edesc;
178 	int ecode = 0;
179 
180 	if (err)
181 		ecode = caam_jr_strstatus(dev, err);
182 
183 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
184 
185 	rsa_priv_f3_unmap(dev, edesc, req);
186 	rsa_io_unmap(dev, edesc, req);
187 	kfree(edesc);
188 
189 	akcipher_request_complete(req, ecode);
190 }
191 
192 /**
193  * Count leading zeros, need it to strip, from a given scatterlist
194  *
195  * @sgl   : scatterlist to count zeros from
196  * @nbytes: number of zeros, in bytes, to strip
197  * @flags : operation flags
198  */
199 static int caam_rsa_count_leading_zeros(struct scatterlist *sgl,
200 					unsigned int nbytes,
201 					unsigned int flags)
202 {
203 	struct sg_mapping_iter miter;
204 	int lzeros, ents;
205 	unsigned int len;
206 	unsigned int tbytes = nbytes;
207 	const u8 *buff;
208 
209 	ents = sg_nents_for_len(sgl, nbytes);
210 	if (ents < 0)
211 		return ents;
212 
213 	sg_miter_start(&miter, sgl, ents, SG_MITER_FROM_SG | flags);
214 
215 	lzeros = 0;
216 	len = 0;
217 	while (nbytes > 0) {
218 		/* do not strip more than given bytes */
219 		while (len && !*buff && lzeros < nbytes) {
220 			lzeros++;
221 			len--;
222 			buff++;
223 		}
224 
225 		if (len && *buff)
226 			break;
227 
228 		sg_miter_next(&miter);
229 		buff = miter.addr;
230 		len = miter.length;
231 
232 		nbytes -= lzeros;
233 		lzeros = 0;
234 	}
235 
236 	miter.consumed = lzeros;
237 	sg_miter_stop(&miter);
238 	nbytes -= lzeros;
239 
240 	return tbytes - nbytes;
241 }
242 
243 static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req,
244 					 size_t desclen)
245 {
246 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
247 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
248 	struct device *dev = ctx->dev;
249 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
250 	struct caam_rsa_key *key = &ctx->key;
251 	struct rsa_edesc *edesc;
252 	gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
253 		       GFP_KERNEL : GFP_ATOMIC;
254 	int sg_flags = (flags == GFP_ATOMIC) ? SG_MITER_ATOMIC : 0;
255 	int sgc;
256 	int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
257 	int src_nents, dst_nents;
258 	unsigned int diff_size = 0;
259 	int lzeros;
260 
261 	if (req->src_len > key->n_sz) {
262 		/*
263 		 * strip leading zeros and
264 		 * return the number of zeros to skip
265 		 */
266 		lzeros = caam_rsa_count_leading_zeros(req->src, req->src_len -
267 						      key->n_sz, sg_flags);
268 		if (lzeros < 0)
269 			return ERR_PTR(lzeros);
270 
271 		req_ctx->fixup_src = scatterwalk_ffwd(req_ctx->src, req->src,
272 						      lzeros);
273 		req_ctx->fixup_src_len = req->src_len - lzeros;
274 	} else {
275 		/*
276 		 * input src is less then n key modulus,
277 		 * so there will be zero padding
278 		 */
279 		diff_size = key->n_sz - req->src_len;
280 		req_ctx->fixup_src = req->src;
281 		req_ctx->fixup_src_len = req->src_len;
282 	}
283 
284 	src_nents = sg_nents_for_len(req_ctx->fixup_src,
285 				     req_ctx->fixup_src_len);
286 	dst_nents = sg_nents_for_len(req->dst, req->dst_len);
287 
288 	if (!diff_size && src_nents == 1)
289 		sec4_sg_len = 0; /* no need for an input hw s/g table */
290 	else
291 		sec4_sg_len = src_nents + !!diff_size;
292 	sec4_sg_index = sec4_sg_len;
293 	if (dst_nents > 1)
294 		sec4_sg_len += pad_sg_nents(dst_nents);
295 	else
296 		sec4_sg_len = pad_sg_nents(sec4_sg_len);
297 
298 	sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry);
299 
300 	/* allocate space for base edesc, hw desc commands and link tables */
301 	edesc = kzalloc(sizeof(*edesc) + desclen + sec4_sg_bytes,
302 			GFP_DMA | flags);
303 	if (!edesc)
304 		return ERR_PTR(-ENOMEM);
305 
306 	sgc = dma_map_sg(dev, req_ctx->fixup_src, src_nents, DMA_TO_DEVICE);
307 	if (unlikely(!sgc)) {
308 		dev_err(dev, "unable to map source\n");
309 		goto src_fail;
310 	}
311 
312 	sgc = dma_map_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
313 	if (unlikely(!sgc)) {
314 		dev_err(dev, "unable to map destination\n");
315 		goto dst_fail;
316 	}
317 
318 	edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen;
319 	if (diff_size)
320 		dma_to_sec4_sg_one(edesc->sec4_sg, ctx->padding_dma, diff_size,
321 				   0);
322 
323 	if (sec4_sg_index)
324 		sg_to_sec4_sg_last(req_ctx->fixup_src, req_ctx->fixup_src_len,
325 				   edesc->sec4_sg + !!diff_size, 0);
326 
327 	if (dst_nents > 1)
328 		sg_to_sec4_sg_last(req->dst, req->dst_len,
329 				   edesc->sec4_sg + sec4_sg_index, 0);
330 
331 	/* Save nents for later use in Job Descriptor */
332 	edesc->src_nents = src_nents;
333 	edesc->dst_nents = dst_nents;
334 
335 	if (!sec4_sg_bytes)
336 		return edesc;
337 
338 	edesc->sec4_sg_dma = dma_map_single(dev, edesc->sec4_sg,
339 					    sec4_sg_bytes, DMA_TO_DEVICE);
340 	if (dma_mapping_error(dev, edesc->sec4_sg_dma)) {
341 		dev_err(dev, "unable to map S/G table\n");
342 		goto sec4_sg_fail;
343 	}
344 
345 	edesc->sec4_sg_bytes = sec4_sg_bytes;
346 
347 	print_hex_dump_debug("caampkc sec4_sg@" __stringify(__LINE__) ": ",
348 			     DUMP_PREFIX_ADDRESS, 16, 4, edesc->sec4_sg,
349 			     edesc->sec4_sg_bytes, 1);
350 
351 	return edesc;
352 
353 sec4_sg_fail:
354 	dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
355 dst_fail:
356 	dma_unmap_sg(dev, req_ctx->fixup_src, src_nents, DMA_TO_DEVICE);
357 src_fail:
358 	kfree(edesc);
359 	return ERR_PTR(-ENOMEM);
360 }
361 
362 static int set_rsa_pub_pdb(struct akcipher_request *req,
363 			   struct rsa_edesc *edesc)
364 {
365 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
366 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
367 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
368 	struct caam_rsa_key *key = &ctx->key;
369 	struct device *dev = ctx->dev;
370 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
371 	int sec4_sg_index = 0;
372 
373 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
374 	if (dma_mapping_error(dev, pdb->n_dma)) {
375 		dev_err(dev, "Unable to map RSA modulus memory\n");
376 		return -ENOMEM;
377 	}
378 
379 	pdb->e_dma = dma_map_single(dev, key->e, key->e_sz, DMA_TO_DEVICE);
380 	if (dma_mapping_error(dev, pdb->e_dma)) {
381 		dev_err(dev, "Unable to map RSA public exponent memory\n");
382 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
383 		return -ENOMEM;
384 	}
385 
386 	if (edesc->src_nents > 1) {
387 		pdb->sgf |= RSA_PDB_SGF_F;
388 		pdb->f_dma = edesc->sec4_sg_dma;
389 		sec4_sg_index += edesc->src_nents;
390 	} else {
391 		pdb->f_dma = sg_dma_address(req_ctx->fixup_src);
392 	}
393 
394 	if (edesc->dst_nents > 1) {
395 		pdb->sgf |= RSA_PDB_SGF_G;
396 		pdb->g_dma = edesc->sec4_sg_dma +
397 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
398 	} else {
399 		pdb->g_dma = sg_dma_address(req->dst);
400 	}
401 
402 	pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz;
403 	pdb->f_len = req_ctx->fixup_src_len;
404 
405 	return 0;
406 }
407 
408 static int set_rsa_priv_f1_pdb(struct akcipher_request *req,
409 			       struct rsa_edesc *edesc)
410 {
411 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
412 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
413 	struct caam_rsa_key *key = &ctx->key;
414 	struct device *dev = ctx->dev;
415 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
416 	int sec4_sg_index = 0;
417 
418 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
419 	if (dma_mapping_error(dev, pdb->n_dma)) {
420 		dev_err(dev, "Unable to map modulus memory\n");
421 		return -ENOMEM;
422 	}
423 
424 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
425 	if (dma_mapping_error(dev, pdb->d_dma)) {
426 		dev_err(dev, "Unable to map RSA private exponent memory\n");
427 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
428 		return -ENOMEM;
429 	}
430 
431 	if (edesc->src_nents > 1) {
432 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
433 		pdb->g_dma = edesc->sec4_sg_dma;
434 		sec4_sg_index += edesc->src_nents;
435 	} else {
436 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
437 
438 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
439 	}
440 
441 	if (edesc->dst_nents > 1) {
442 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
443 		pdb->f_dma = edesc->sec4_sg_dma +
444 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
445 	} else {
446 		pdb->f_dma = sg_dma_address(req->dst);
447 	}
448 
449 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
450 
451 	return 0;
452 }
453 
454 static int set_rsa_priv_f2_pdb(struct akcipher_request *req,
455 			       struct rsa_edesc *edesc)
456 {
457 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
458 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
459 	struct caam_rsa_key *key = &ctx->key;
460 	struct device *dev = ctx->dev;
461 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
462 	int sec4_sg_index = 0;
463 	size_t p_sz = key->p_sz;
464 	size_t q_sz = key->q_sz;
465 
466 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
467 	if (dma_mapping_error(dev, pdb->d_dma)) {
468 		dev_err(dev, "Unable to map RSA private exponent memory\n");
469 		return -ENOMEM;
470 	}
471 
472 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
473 	if (dma_mapping_error(dev, pdb->p_dma)) {
474 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
475 		goto unmap_d;
476 	}
477 
478 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
479 	if (dma_mapping_error(dev, pdb->q_dma)) {
480 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
481 		goto unmap_p;
482 	}
483 
484 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
485 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
486 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
487 		goto unmap_q;
488 	}
489 
490 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
491 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
492 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
493 		goto unmap_tmp1;
494 	}
495 
496 	if (edesc->src_nents > 1) {
497 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
498 		pdb->g_dma = edesc->sec4_sg_dma;
499 		sec4_sg_index += edesc->src_nents;
500 	} else {
501 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
502 
503 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
504 	}
505 
506 	if (edesc->dst_nents > 1) {
507 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
508 		pdb->f_dma = edesc->sec4_sg_dma +
509 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
510 	} else {
511 		pdb->f_dma = sg_dma_address(req->dst);
512 	}
513 
514 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
515 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
516 
517 	return 0;
518 
519 unmap_tmp1:
520 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
521 unmap_q:
522 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
523 unmap_p:
524 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
525 unmap_d:
526 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
527 
528 	return -ENOMEM;
529 }
530 
531 static int set_rsa_priv_f3_pdb(struct akcipher_request *req,
532 			       struct rsa_edesc *edesc)
533 {
534 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
535 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
536 	struct caam_rsa_key *key = &ctx->key;
537 	struct device *dev = ctx->dev;
538 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
539 	int sec4_sg_index = 0;
540 	size_t p_sz = key->p_sz;
541 	size_t q_sz = key->q_sz;
542 
543 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
544 	if (dma_mapping_error(dev, pdb->p_dma)) {
545 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
546 		return -ENOMEM;
547 	}
548 
549 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
550 	if (dma_mapping_error(dev, pdb->q_dma)) {
551 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
552 		goto unmap_p;
553 	}
554 
555 	pdb->dp_dma = dma_map_single(dev, key->dp, p_sz, DMA_TO_DEVICE);
556 	if (dma_mapping_error(dev, pdb->dp_dma)) {
557 		dev_err(dev, "Unable to map RSA exponent dp memory\n");
558 		goto unmap_q;
559 	}
560 
561 	pdb->dq_dma = dma_map_single(dev, key->dq, q_sz, DMA_TO_DEVICE);
562 	if (dma_mapping_error(dev, pdb->dq_dma)) {
563 		dev_err(dev, "Unable to map RSA exponent dq memory\n");
564 		goto unmap_dp;
565 	}
566 
567 	pdb->c_dma = dma_map_single(dev, key->qinv, p_sz, DMA_TO_DEVICE);
568 	if (dma_mapping_error(dev, pdb->c_dma)) {
569 		dev_err(dev, "Unable to map RSA CRT coefficient qinv memory\n");
570 		goto unmap_dq;
571 	}
572 
573 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
574 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
575 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
576 		goto unmap_qinv;
577 	}
578 
579 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
580 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
581 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
582 		goto unmap_tmp1;
583 	}
584 
585 	if (edesc->src_nents > 1) {
586 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
587 		pdb->g_dma = edesc->sec4_sg_dma;
588 		sec4_sg_index += edesc->src_nents;
589 	} else {
590 		struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
591 
592 		pdb->g_dma = sg_dma_address(req_ctx->fixup_src);
593 	}
594 
595 	if (edesc->dst_nents > 1) {
596 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
597 		pdb->f_dma = edesc->sec4_sg_dma +
598 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
599 	} else {
600 		pdb->f_dma = sg_dma_address(req->dst);
601 	}
602 
603 	pdb->sgf |= key->n_sz;
604 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
605 
606 	return 0;
607 
608 unmap_tmp1:
609 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
610 unmap_qinv:
611 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
612 unmap_dq:
613 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
614 unmap_dp:
615 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
616 unmap_q:
617 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
618 unmap_p:
619 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
620 
621 	return -ENOMEM;
622 }
623 
624 static int caam_rsa_enc(struct akcipher_request *req)
625 {
626 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
627 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
628 	struct caam_rsa_key *key = &ctx->key;
629 	struct device *jrdev = ctx->dev;
630 	struct rsa_edesc *edesc;
631 	int ret;
632 
633 	if (unlikely(!key->n || !key->e))
634 		return -EINVAL;
635 
636 	if (req->dst_len < key->n_sz) {
637 		req->dst_len = key->n_sz;
638 		dev_err(jrdev, "Output buffer length less than parameter n\n");
639 		return -EOVERFLOW;
640 	}
641 
642 	/* Allocate extended descriptor */
643 	edesc = rsa_edesc_alloc(req, DESC_RSA_PUB_LEN);
644 	if (IS_ERR(edesc))
645 		return PTR_ERR(edesc);
646 
647 	/* Set RSA Encrypt Protocol Data Block */
648 	ret = set_rsa_pub_pdb(req, edesc);
649 	if (ret)
650 		goto init_fail;
651 
652 	/* Initialize Job Descriptor */
653 	init_rsa_pub_desc(edesc->hw_desc, &edesc->pdb.pub);
654 
655 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_pub_done, req);
656 	if (!ret)
657 		return -EINPROGRESS;
658 
659 	rsa_pub_unmap(jrdev, edesc, req);
660 
661 init_fail:
662 	rsa_io_unmap(jrdev, edesc, req);
663 	kfree(edesc);
664 	return ret;
665 }
666 
667 static int caam_rsa_dec_priv_f1(struct akcipher_request *req)
668 {
669 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
670 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
671 	struct device *jrdev = ctx->dev;
672 	struct rsa_edesc *edesc;
673 	int ret;
674 
675 	/* Allocate extended descriptor */
676 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F1_LEN);
677 	if (IS_ERR(edesc))
678 		return PTR_ERR(edesc);
679 
680 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #1 */
681 	ret = set_rsa_priv_f1_pdb(req, edesc);
682 	if (ret)
683 		goto init_fail;
684 
685 	/* Initialize Job Descriptor */
686 	init_rsa_priv_f1_desc(edesc->hw_desc, &edesc->pdb.priv_f1);
687 
688 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f1_done, req);
689 	if (!ret)
690 		return -EINPROGRESS;
691 
692 	rsa_priv_f1_unmap(jrdev, edesc, req);
693 
694 init_fail:
695 	rsa_io_unmap(jrdev, edesc, req);
696 	kfree(edesc);
697 	return ret;
698 }
699 
700 static int caam_rsa_dec_priv_f2(struct akcipher_request *req)
701 {
702 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
703 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
704 	struct device *jrdev = ctx->dev;
705 	struct rsa_edesc *edesc;
706 	int ret;
707 
708 	/* Allocate extended descriptor */
709 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F2_LEN);
710 	if (IS_ERR(edesc))
711 		return PTR_ERR(edesc);
712 
713 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #2 */
714 	ret = set_rsa_priv_f2_pdb(req, edesc);
715 	if (ret)
716 		goto init_fail;
717 
718 	/* Initialize Job Descriptor */
719 	init_rsa_priv_f2_desc(edesc->hw_desc, &edesc->pdb.priv_f2);
720 
721 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f2_done, req);
722 	if (!ret)
723 		return -EINPROGRESS;
724 
725 	rsa_priv_f2_unmap(jrdev, edesc, req);
726 
727 init_fail:
728 	rsa_io_unmap(jrdev, edesc, req);
729 	kfree(edesc);
730 	return ret;
731 }
732 
733 static int caam_rsa_dec_priv_f3(struct akcipher_request *req)
734 {
735 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
736 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
737 	struct device *jrdev = ctx->dev;
738 	struct rsa_edesc *edesc;
739 	int ret;
740 
741 	/* Allocate extended descriptor */
742 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F3_LEN);
743 	if (IS_ERR(edesc))
744 		return PTR_ERR(edesc);
745 
746 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #3 */
747 	ret = set_rsa_priv_f3_pdb(req, edesc);
748 	if (ret)
749 		goto init_fail;
750 
751 	/* Initialize Job Descriptor */
752 	init_rsa_priv_f3_desc(edesc->hw_desc, &edesc->pdb.priv_f3);
753 
754 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f3_done, req);
755 	if (!ret)
756 		return -EINPROGRESS;
757 
758 	rsa_priv_f3_unmap(jrdev, edesc, req);
759 
760 init_fail:
761 	rsa_io_unmap(jrdev, edesc, req);
762 	kfree(edesc);
763 	return ret;
764 }
765 
766 static int caam_rsa_dec(struct akcipher_request *req)
767 {
768 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
769 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
770 	struct caam_rsa_key *key = &ctx->key;
771 	int ret;
772 
773 	if (unlikely(!key->n || !key->d))
774 		return -EINVAL;
775 
776 	if (req->dst_len < key->n_sz) {
777 		req->dst_len = key->n_sz;
778 		dev_err(ctx->dev, "Output buffer length less than parameter n\n");
779 		return -EOVERFLOW;
780 	}
781 
782 	if (key->priv_form == FORM3)
783 		ret = caam_rsa_dec_priv_f3(req);
784 	else if (key->priv_form == FORM2)
785 		ret = caam_rsa_dec_priv_f2(req);
786 	else
787 		ret = caam_rsa_dec_priv_f1(req);
788 
789 	return ret;
790 }
791 
792 static void caam_rsa_free_key(struct caam_rsa_key *key)
793 {
794 	kzfree(key->d);
795 	kzfree(key->p);
796 	kzfree(key->q);
797 	kzfree(key->dp);
798 	kzfree(key->dq);
799 	kzfree(key->qinv);
800 	kzfree(key->tmp1);
801 	kzfree(key->tmp2);
802 	kfree(key->e);
803 	kfree(key->n);
804 	memset(key, 0, sizeof(*key));
805 }
806 
807 static void caam_rsa_drop_leading_zeros(const u8 **ptr, size_t *nbytes)
808 {
809 	while (!**ptr && *nbytes) {
810 		(*ptr)++;
811 		(*nbytes)--;
812 	}
813 }
814 
815 /**
816  * caam_read_rsa_crt - Used for reading dP, dQ, qInv CRT members.
817  * dP, dQ and qInv could decode to less than corresponding p, q length, as the
818  * BER-encoding requires that the minimum number of bytes be used to encode the
819  * integer. dP, dQ, qInv decoded values have to be zero-padded to appropriate
820  * length.
821  *
822  * @ptr   : pointer to {dP, dQ, qInv} CRT member
823  * @nbytes: length in bytes of {dP, dQ, qInv} CRT member
824  * @dstlen: length in bytes of corresponding p or q prime factor
825  */
826 static u8 *caam_read_rsa_crt(const u8 *ptr, size_t nbytes, size_t dstlen)
827 {
828 	u8 *dst;
829 
830 	caam_rsa_drop_leading_zeros(&ptr, &nbytes);
831 	if (!nbytes)
832 		return NULL;
833 
834 	dst = kzalloc(dstlen, GFP_DMA | GFP_KERNEL);
835 	if (!dst)
836 		return NULL;
837 
838 	memcpy(dst + (dstlen - nbytes), ptr, nbytes);
839 
840 	return dst;
841 }
842 
843 /**
844  * caam_read_raw_data - Read a raw byte stream as a positive integer.
845  * The function skips buffer's leading zeros, copies the remained data
846  * to a buffer allocated in the GFP_DMA | GFP_KERNEL zone and returns
847  * the address of the new buffer.
848  *
849  * @buf   : The data to read
850  * @nbytes: The amount of data to read
851  */
852 static inline u8 *caam_read_raw_data(const u8 *buf, size_t *nbytes)
853 {
854 
855 	caam_rsa_drop_leading_zeros(&buf, nbytes);
856 	if (!*nbytes)
857 		return NULL;
858 
859 	return kmemdup(buf, *nbytes, GFP_DMA | GFP_KERNEL);
860 }
861 
862 static int caam_rsa_check_key_length(unsigned int len)
863 {
864 	if (len > 4096)
865 		return -EINVAL;
866 	return 0;
867 }
868 
869 static int caam_rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
870 				unsigned int keylen)
871 {
872 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
873 	struct rsa_key raw_key = {NULL};
874 	struct caam_rsa_key *rsa_key = &ctx->key;
875 	int ret;
876 
877 	/* Free the old RSA key if any */
878 	caam_rsa_free_key(rsa_key);
879 
880 	ret = rsa_parse_pub_key(&raw_key, key, keylen);
881 	if (ret)
882 		return ret;
883 
884 	/* Copy key in DMA zone */
885 	rsa_key->e = kmemdup(raw_key.e, raw_key.e_sz, GFP_DMA | GFP_KERNEL);
886 	if (!rsa_key->e)
887 		goto err;
888 
889 	/*
890 	 * Skip leading zeros and copy the positive integer to a buffer
891 	 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
892 	 * expects a positive integer for the RSA modulus and uses its length as
893 	 * decryption output length.
894 	 */
895 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
896 	if (!rsa_key->n)
897 		goto err;
898 
899 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
900 		caam_rsa_free_key(rsa_key);
901 		return -EINVAL;
902 	}
903 
904 	rsa_key->e_sz = raw_key.e_sz;
905 	rsa_key->n_sz = raw_key.n_sz;
906 
907 	return 0;
908 err:
909 	caam_rsa_free_key(rsa_key);
910 	return -ENOMEM;
911 }
912 
913 static void caam_rsa_set_priv_key_form(struct caam_rsa_ctx *ctx,
914 				       struct rsa_key *raw_key)
915 {
916 	struct caam_rsa_key *rsa_key = &ctx->key;
917 	size_t p_sz = raw_key->p_sz;
918 	size_t q_sz = raw_key->q_sz;
919 
920 	rsa_key->p = caam_read_raw_data(raw_key->p, &p_sz);
921 	if (!rsa_key->p)
922 		return;
923 	rsa_key->p_sz = p_sz;
924 
925 	rsa_key->q = caam_read_raw_data(raw_key->q, &q_sz);
926 	if (!rsa_key->q)
927 		goto free_p;
928 	rsa_key->q_sz = q_sz;
929 
930 	rsa_key->tmp1 = kzalloc(raw_key->p_sz, GFP_DMA | GFP_KERNEL);
931 	if (!rsa_key->tmp1)
932 		goto free_q;
933 
934 	rsa_key->tmp2 = kzalloc(raw_key->q_sz, GFP_DMA | GFP_KERNEL);
935 	if (!rsa_key->tmp2)
936 		goto free_tmp1;
937 
938 	rsa_key->priv_form = FORM2;
939 
940 	rsa_key->dp = caam_read_rsa_crt(raw_key->dp, raw_key->dp_sz, p_sz);
941 	if (!rsa_key->dp)
942 		goto free_tmp2;
943 
944 	rsa_key->dq = caam_read_rsa_crt(raw_key->dq, raw_key->dq_sz, q_sz);
945 	if (!rsa_key->dq)
946 		goto free_dp;
947 
948 	rsa_key->qinv = caam_read_rsa_crt(raw_key->qinv, raw_key->qinv_sz,
949 					  q_sz);
950 	if (!rsa_key->qinv)
951 		goto free_dq;
952 
953 	rsa_key->priv_form = FORM3;
954 
955 	return;
956 
957 free_dq:
958 	kzfree(rsa_key->dq);
959 free_dp:
960 	kzfree(rsa_key->dp);
961 free_tmp2:
962 	kzfree(rsa_key->tmp2);
963 free_tmp1:
964 	kzfree(rsa_key->tmp1);
965 free_q:
966 	kzfree(rsa_key->q);
967 free_p:
968 	kzfree(rsa_key->p);
969 }
970 
971 static int caam_rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
972 				 unsigned int keylen)
973 {
974 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
975 	struct rsa_key raw_key = {NULL};
976 	struct caam_rsa_key *rsa_key = &ctx->key;
977 	int ret;
978 
979 	/* Free the old RSA key if any */
980 	caam_rsa_free_key(rsa_key);
981 
982 	ret = rsa_parse_priv_key(&raw_key, key, keylen);
983 	if (ret)
984 		return ret;
985 
986 	/* Copy key in DMA zone */
987 	rsa_key->d = kmemdup(raw_key.d, raw_key.d_sz, GFP_DMA | GFP_KERNEL);
988 	if (!rsa_key->d)
989 		goto err;
990 
991 	rsa_key->e = kmemdup(raw_key.e, raw_key.e_sz, GFP_DMA | GFP_KERNEL);
992 	if (!rsa_key->e)
993 		goto err;
994 
995 	/*
996 	 * Skip leading zeros and copy the positive integer to a buffer
997 	 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
998 	 * expects a positive integer for the RSA modulus and uses its length as
999 	 * decryption output length.
1000 	 */
1001 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
1002 	if (!rsa_key->n)
1003 		goto err;
1004 
1005 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
1006 		caam_rsa_free_key(rsa_key);
1007 		return -EINVAL;
1008 	}
1009 
1010 	rsa_key->d_sz = raw_key.d_sz;
1011 	rsa_key->e_sz = raw_key.e_sz;
1012 	rsa_key->n_sz = raw_key.n_sz;
1013 
1014 	caam_rsa_set_priv_key_form(ctx, &raw_key);
1015 
1016 	return 0;
1017 
1018 err:
1019 	caam_rsa_free_key(rsa_key);
1020 	return -ENOMEM;
1021 }
1022 
1023 static unsigned int caam_rsa_max_size(struct crypto_akcipher *tfm)
1024 {
1025 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1026 
1027 	return ctx->key.n_sz;
1028 }
1029 
1030 /* Per session pkc's driver context creation function */
1031 static int caam_rsa_init_tfm(struct crypto_akcipher *tfm)
1032 {
1033 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1034 
1035 	ctx->dev = caam_jr_alloc();
1036 
1037 	if (IS_ERR(ctx->dev)) {
1038 		pr_err("Job Ring Device allocation for transform failed\n");
1039 		return PTR_ERR(ctx->dev);
1040 	}
1041 
1042 	ctx->padding_dma = dma_map_single(ctx->dev, zero_buffer,
1043 					  CAAM_RSA_MAX_INPUT_SIZE - 1,
1044 					  DMA_TO_DEVICE);
1045 	if (dma_mapping_error(ctx->dev, ctx->padding_dma)) {
1046 		dev_err(ctx->dev, "unable to map padding\n");
1047 		caam_jr_free(ctx->dev);
1048 		return -ENOMEM;
1049 	}
1050 
1051 	return 0;
1052 }
1053 
1054 /* Per session pkc's driver context cleanup function */
1055 static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
1056 {
1057 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
1058 	struct caam_rsa_key *key = &ctx->key;
1059 
1060 	dma_unmap_single(ctx->dev, ctx->padding_dma, CAAM_RSA_MAX_INPUT_SIZE -
1061 			 1, DMA_TO_DEVICE);
1062 	caam_rsa_free_key(key);
1063 	caam_jr_free(ctx->dev);
1064 }
1065 
1066 static struct caam_akcipher_alg caam_rsa = {
1067 	.akcipher = {
1068 		.encrypt = caam_rsa_enc,
1069 		.decrypt = caam_rsa_dec,
1070 		.set_pub_key = caam_rsa_set_pub_key,
1071 		.set_priv_key = caam_rsa_set_priv_key,
1072 		.max_size = caam_rsa_max_size,
1073 		.init = caam_rsa_init_tfm,
1074 		.exit = caam_rsa_exit_tfm,
1075 		.reqsize = sizeof(struct caam_rsa_req_ctx),
1076 		.base = {
1077 			.cra_name = "rsa",
1078 			.cra_driver_name = "rsa-caam",
1079 			.cra_priority = 3000,
1080 			.cra_module = THIS_MODULE,
1081 			.cra_ctxsize = sizeof(struct caam_rsa_ctx),
1082 		},
1083 	}
1084 };
1085 
1086 /* Public Key Cryptography module initialization handler */
1087 int caam_pkc_init(struct device *ctrldev)
1088 {
1089 	struct caam_drv_private *priv = dev_get_drvdata(ctrldev);
1090 	u32 pk_inst;
1091 	int err;
1092 	init_done = false;
1093 
1094 	/* Determine public key hardware accelerator presence. */
1095 	if (priv->era < 10)
1096 		pk_inst = (rd_reg32(&priv->ctrl->perfmon.cha_num_ls) &
1097 			   CHA_ID_LS_PK_MASK) >> CHA_ID_LS_PK_SHIFT;
1098 	else
1099 		pk_inst = rd_reg32(&priv->ctrl->vreg.pkha) & CHA_VER_NUM_MASK;
1100 
1101 	/* Do not register algorithms if PKHA is not present. */
1102 	if (!pk_inst)
1103 		return 0;
1104 
1105 	/* allocate zero buffer, used for padding input */
1106 	zero_buffer = kzalloc(CAAM_RSA_MAX_INPUT_SIZE - 1, GFP_DMA |
1107 			      GFP_KERNEL);
1108 	if (!zero_buffer)
1109 		return -ENOMEM;
1110 
1111 	err = crypto_register_akcipher(&caam_rsa.akcipher);
1112 
1113 	if (err) {
1114 		kfree(zero_buffer);
1115 		dev_warn(ctrldev, "%s alg registration failed\n",
1116 			 caam_rsa.akcipher.base.cra_driver_name);
1117 	} else {
1118 		init_done = true;
1119 		caam_rsa.registered = true;
1120 		dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n");
1121 	}
1122 
1123 	return err;
1124 }
1125 
1126 void caam_pkc_exit(void)
1127 {
1128 	if (!init_done)
1129 		return;
1130 
1131 	if (caam_rsa.registered)
1132 		crypto_unregister_akcipher(&caam_rsa.akcipher);
1133 
1134 	kfree(zero_buffer);
1135 }
1136