xref: /openbmc/linux/drivers/crypto/caam/caampkc.c (revision be709d48)
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 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(struct rsa_pub_pdb))
21 #define DESC_RSA_PRIV_F1_LEN	(2 * CAAM_CMD_SZ + \
22 				 sizeof(struct rsa_priv_f1_pdb))
23 #define DESC_RSA_PRIV_F2_LEN	(2 * CAAM_CMD_SZ + \
24 				 sizeof(struct rsa_priv_f2_pdb))
25 #define DESC_RSA_PRIV_F3_LEN	(2 * CAAM_CMD_SZ + \
26 				 sizeof(struct rsa_priv_f3_pdb))
27 
28 static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
29 			 struct akcipher_request *req)
30 {
31 	dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
32 	dma_unmap_sg(dev, req->src, edesc->src_nents, DMA_TO_DEVICE);
33 
34 	if (edesc->sec4_sg_bytes)
35 		dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
36 				 DMA_TO_DEVICE);
37 }
38 
39 static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
40 			  struct akcipher_request *req)
41 {
42 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
43 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
44 	struct caam_rsa_key *key = &ctx->key;
45 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
46 
47 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
48 	dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
49 }
50 
51 static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
52 			      struct akcipher_request *req)
53 {
54 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
55 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
56 	struct caam_rsa_key *key = &ctx->key;
57 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
58 
59 	dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
60 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
61 }
62 
63 static void rsa_priv_f2_unmap(struct device *dev, struct rsa_edesc *edesc,
64 			      struct akcipher_request *req)
65 {
66 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
67 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
68 	struct caam_rsa_key *key = &ctx->key;
69 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
70 	size_t p_sz = key->p_sz;
71 	size_t q_sz = key->q_sz;
72 
73 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
74 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
75 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
76 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
77 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
78 }
79 
80 static void rsa_priv_f3_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_f3_pdb *pdb = &edesc->pdb.priv_f3;
87 	size_t p_sz = key->p_sz;
88 	size_t q_sz = key->q_sz;
89 
90 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
91 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
92 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
93 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
94 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
95 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
96 	dma_unmap_single(dev, pdb->tmp2_dma, q_sz, DMA_BIDIRECTIONAL);
97 }
98 
99 /* RSA Job Completion handler */
100 static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
101 {
102 	struct akcipher_request *req = context;
103 	struct rsa_edesc *edesc;
104 
105 	if (err)
106 		caam_jr_strstatus(dev, err);
107 
108 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
109 
110 	rsa_pub_unmap(dev, edesc, req);
111 	rsa_io_unmap(dev, edesc, req);
112 	kfree(edesc);
113 
114 	akcipher_request_complete(req, err);
115 }
116 
117 static void rsa_priv_f1_done(struct device *dev, u32 *desc, u32 err,
118 			     void *context)
119 {
120 	struct akcipher_request *req = context;
121 	struct rsa_edesc *edesc;
122 
123 	if (err)
124 		caam_jr_strstatus(dev, err);
125 
126 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
127 
128 	rsa_priv_f1_unmap(dev, edesc, req);
129 	rsa_io_unmap(dev, edesc, req);
130 	kfree(edesc);
131 
132 	akcipher_request_complete(req, err);
133 }
134 
135 static void rsa_priv_f2_done(struct device *dev, u32 *desc, u32 err,
136 			     void *context)
137 {
138 	struct akcipher_request *req = context;
139 	struct rsa_edesc *edesc;
140 
141 	if (err)
142 		caam_jr_strstatus(dev, err);
143 
144 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
145 
146 	rsa_priv_f2_unmap(dev, edesc, req);
147 	rsa_io_unmap(dev, edesc, req);
148 	kfree(edesc);
149 
150 	akcipher_request_complete(req, err);
151 }
152 
153 static void rsa_priv_f3_done(struct device *dev, u32 *desc, u32 err,
154 			     void *context)
155 {
156 	struct akcipher_request *req = context;
157 	struct rsa_edesc *edesc;
158 
159 	if (err)
160 		caam_jr_strstatus(dev, err);
161 
162 	edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
163 
164 	rsa_priv_f3_unmap(dev, edesc, req);
165 	rsa_io_unmap(dev, edesc, req);
166 	kfree(edesc);
167 
168 	akcipher_request_complete(req, err);
169 }
170 
171 static int caam_rsa_count_leading_zeros(struct scatterlist *sgl,
172 					unsigned int nbytes,
173 					unsigned int flags)
174 {
175 	struct sg_mapping_iter miter;
176 	int lzeros, ents;
177 	unsigned int len;
178 	unsigned int tbytes = nbytes;
179 	const u8 *buff;
180 
181 	ents = sg_nents_for_len(sgl, nbytes);
182 	if (ents < 0)
183 		return ents;
184 
185 	sg_miter_start(&miter, sgl, ents, SG_MITER_FROM_SG | flags);
186 
187 	lzeros = 0;
188 	len = 0;
189 	while (nbytes > 0) {
190 		while (len && !*buff) {
191 			lzeros++;
192 			len--;
193 			buff++;
194 		}
195 
196 		if (len && *buff)
197 			break;
198 
199 		sg_miter_next(&miter);
200 		buff = miter.addr;
201 		len = miter.length;
202 
203 		nbytes -= lzeros;
204 		lzeros = 0;
205 	}
206 
207 	miter.consumed = lzeros;
208 	sg_miter_stop(&miter);
209 	nbytes -= lzeros;
210 
211 	return tbytes - nbytes;
212 }
213 
214 static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req,
215 					 size_t desclen)
216 {
217 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
218 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
219 	struct device *dev = ctx->dev;
220 	struct caam_rsa_req_ctx *req_ctx = akcipher_request_ctx(req);
221 	struct rsa_edesc *edesc;
222 	gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
223 		       GFP_KERNEL : GFP_ATOMIC;
224 	int sg_flags = (flags == GFP_ATOMIC) ? SG_MITER_ATOMIC : 0;
225 	int sgc;
226 	int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
227 	int src_nents, dst_nents;
228 	int lzeros;
229 
230 	lzeros = caam_rsa_count_leading_zeros(req->src, req->src_len, sg_flags);
231 	if (lzeros < 0)
232 		return ERR_PTR(lzeros);
233 
234 	req->src_len -= lzeros;
235 	req->src = scatterwalk_ffwd(req_ctx->src, req->src, lzeros);
236 
237 	src_nents = sg_nents_for_len(req->src, req->src_len);
238 	dst_nents = sg_nents_for_len(req->dst, req->dst_len);
239 
240 	if (src_nents > 1)
241 		sec4_sg_len = src_nents;
242 	if (dst_nents > 1)
243 		sec4_sg_len += dst_nents;
244 
245 	sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry);
246 
247 	/* allocate space for base edesc, hw desc commands and link tables */
248 	edesc = kzalloc(sizeof(*edesc) + desclen + sec4_sg_bytes,
249 			GFP_DMA | flags);
250 	if (!edesc)
251 		return ERR_PTR(-ENOMEM);
252 
253 	sgc = dma_map_sg(dev, req->src, src_nents, DMA_TO_DEVICE);
254 	if (unlikely(!sgc)) {
255 		dev_err(dev, "unable to map source\n");
256 		goto src_fail;
257 	}
258 
259 	sgc = dma_map_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
260 	if (unlikely(!sgc)) {
261 		dev_err(dev, "unable to map destination\n");
262 		goto dst_fail;
263 	}
264 
265 	edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen;
266 
267 	sec4_sg_index = 0;
268 	if (src_nents > 1) {
269 		sg_to_sec4_sg_last(req->src, src_nents, edesc->sec4_sg, 0);
270 		sec4_sg_index += src_nents;
271 	}
272 	if (dst_nents > 1)
273 		sg_to_sec4_sg_last(req->dst, dst_nents,
274 				   edesc->sec4_sg + sec4_sg_index, 0);
275 
276 	/* Save nents for later use in Job Descriptor */
277 	edesc->src_nents = src_nents;
278 	edesc->dst_nents = dst_nents;
279 
280 	if (!sec4_sg_bytes)
281 		return edesc;
282 
283 	edesc->sec4_sg_dma = dma_map_single(dev, edesc->sec4_sg,
284 					    sec4_sg_bytes, DMA_TO_DEVICE);
285 	if (dma_mapping_error(dev, edesc->sec4_sg_dma)) {
286 		dev_err(dev, "unable to map S/G table\n");
287 		goto sec4_sg_fail;
288 	}
289 
290 	edesc->sec4_sg_bytes = sec4_sg_bytes;
291 
292 	return edesc;
293 
294 sec4_sg_fail:
295 	dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
296 dst_fail:
297 	dma_unmap_sg(dev, req->src, src_nents, DMA_TO_DEVICE);
298 src_fail:
299 	kfree(edesc);
300 	return ERR_PTR(-ENOMEM);
301 }
302 
303 static int set_rsa_pub_pdb(struct akcipher_request *req,
304 			   struct rsa_edesc *edesc)
305 {
306 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
307 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
308 	struct caam_rsa_key *key = &ctx->key;
309 	struct device *dev = ctx->dev;
310 	struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
311 	int sec4_sg_index = 0;
312 
313 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
314 	if (dma_mapping_error(dev, pdb->n_dma)) {
315 		dev_err(dev, "Unable to map RSA modulus memory\n");
316 		return -ENOMEM;
317 	}
318 
319 	pdb->e_dma = dma_map_single(dev, key->e, key->e_sz, DMA_TO_DEVICE);
320 	if (dma_mapping_error(dev, pdb->e_dma)) {
321 		dev_err(dev, "Unable to map RSA public exponent memory\n");
322 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
323 		return -ENOMEM;
324 	}
325 
326 	if (edesc->src_nents > 1) {
327 		pdb->sgf |= RSA_PDB_SGF_F;
328 		pdb->f_dma = edesc->sec4_sg_dma;
329 		sec4_sg_index += edesc->src_nents;
330 	} else {
331 		pdb->f_dma = sg_dma_address(req->src);
332 	}
333 
334 	if (edesc->dst_nents > 1) {
335 		pdb->sgf |= RSA_PDB_SGF_G;
336 		pdb->g_dma = edesc->sec4_sg_dma +
337 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
338 	} else {
339 		pdb->g_dma = sg_dma_address(req->dst);
340 	}
341 
342 	pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz;
343 	pdb->f_len = req->src_len;
344 
345 	return 0;
346 }
347 
348 static int set_rsa_priv_f1_pdb(struct akcipher_request *req,
349 			       struct rsa_edesc *edesc)
350 {
351 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
352 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
353 	struct caam_rsa_key *key = &ctx->key;
354 	struct device *dev = ctx->dev;
355 	struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
356 	int sec4_sg_index = 0;
357 
358 	pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
359 	if (dma_mapping_error(dev, pdb->n_dma)) {
360 		dev_err(dev, "Unable to map modulus memory\n");
361 		return -ENOMEM;
362 	}
363 
364 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
365 	if (dma_mapping_error(dev, pdb->d_dma)) {
366 		dev_err(dev, "Unable to map RSA private exponent memory\n");
367 		dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
368 		return -ENOMEM;
369 	}
370 
371 	if (edesc->src_nents > 1) {
372 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
373 		pdb->g_dma = edesc->sec4_sg_dma;
374 		sec4_sg_index += edesc->src_nents;
375 	} else {
376 		pdb->g_dma = sg_dma_address(req->src);
377 	}
378 
379 	if (edesc->dst_nents > 1) {
380 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
381 		pdb->f_dma = edesc->sec4_sg_dma +
382 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
383 	} else {
384 		pdb->f_dma = sg_dma_address(req->dst);
385 	}
386 
387 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
388 
389 	return 0;
390 }
391 
392 static int set_rsa_priv_f2_pdb(struct akcipher_request *req,
393 			       struct rsa_edesc *edesc)
394 {
395 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
396 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
397 	struct caam_rsa_key *key = &ctx->key;
398 	struct device *dev = ctx->dev;
399 	struct rsa_priv_f2_pdb *pdb = &edesc->pdb.priv_f2;
400 	int sec4_sg_index = 0;
401 	size_t p_sz = key->p_sz;
402 	size_t q_sz = key->q_sz;
403 
404 	pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
405 	if (dma_mapping_error(dev, pdb->d_dma)) {
406 		dev_err(dev, "Unable to map RSA private exponent memory\n");
407 		return -ENOMEM;
408 	}
409 
410 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
411 	if (dma_mapping_error(dev, pdb->p_dma)) {
412 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
413 		goto unmap_d;
414 	}
415 
416 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
417 	if (dma_mapping_error(dev, pdb->q_dma)) {
418 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
419 		goto unmap_p;
420 	}
421 
422 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
423 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
424 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
425 		goto unmap_q;
426 	}
427 
428 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
429 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
430 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
431 		goto unmap_tmp1;
432 	}
433 
434 	if (edesc->src_nents > 1) {
435 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
436 		pdb->g_dma = edesc->sec4_sg_dma;
437 		sec4_sg_index += edesc->src_nents;
438 	} else {
439 		pdb->g_dma = sg_dma_address(req->src);
440 	}
441 
442 	if (edesc->dst_nents > 1) {
443 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
444 		pdb->f_dma = edesc->sec4_sg_dma +
445 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
446 	} else {
447 		pdb->f_dma = sg_dma_address(req->dst);
448 	}
449 
450 	pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
451 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
452 
453 	return 0;
454 
455 unmap_tmp1:
456 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
457 unmap_q:
458 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
459 unmap_p:
460 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
461 unmap_d:
462 	dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
463 
464 	return -ENOMEM;
465 }
466 
467 static int set_rsa_priv_f3_pdb(struct akcipher_request *req,
468 			       struct rsa_edesc *edesc)
469 {
470 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
471 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
472 	struct caam_rsa_key *key = &ctx->key;
473 	struct device *dev = ctx->dev;
474 	struct rsa_priv_f3_pdb *pdb = &edesc->pdb.priv_f3;
475 	int sec4_sg_index = 0;
476 	size_t p_sz = key->p_sz;
477 	size_t q_sz = key->q_sz;
478 
479 	pdb->p_dma = dma_map_single(dev, key->p, p_sz, DMA_TO_DEVICE);
480 	if (dma_mapping_error(dev, pdb->p_dma)) {
481 		dev_err(dev, "Unable to map RSA prime factor p memory\n");
482 		return -ENOMEM;
483 	}
484 
485 	pdb->q_dma = dma_map_single(dev, key->q, q_sz, DMA_TO_DEVICE);
486 	if (dma_mapping_error(dev, pdb->q_dma)) {
487 		dev_err(dev, "Unable to map RSA prime factor q memory\n");
488 		goto unmap_p;
489 	}
490 
491 	pdb->dp_dma = dma_map_single(dev, key->dp, p_sz, DMA_TO_DEVICE);
492 	if (dma_mapping_error(dev, pdb->dp_dma)) {
493 		dev_err(dev, "Unable to map RSA exponent dp memory\n");
494 		goto unmap_q;
495 	}
496 
497 	pdb->dq_dma = dma_map_single(dev, key->dq, q_sz, DMA_TO_DEVICE);
498 	if (dma_mapping_error(dev, pdb->dq_dma)) {
499 		dev_err(dev, "Unable to map RSA exponent dq memory\n");
500 		goto unmap_dp;
501 	}
502 
503 	pdb->c_dma = dma_map_single(dev, key->qinv, p_sz, DMA_TO_DEVICE);
504 	if (dma_mapping_error(dev, pdb->c_dma)) {
505 		dev_err(dev, "Unable to map RSA CRT coefficient qinv memory\n");
506 		goto unmap_dq;
507 	}
508 
509 	pdb->tmp1_dma = dma_map_single(dev, key->tmp1, p_sz, DMA_BIDIRECTIONAL);
510 	if (dma_mapping_error(dev, pdb->tmp1_dma)) {
511 		dev_err(dev, "Unable to map RSA tmp1 memory\n");
512 		goto unmap_qinv;
513 	}
514 
515 	pdb->tmp2_dma = dma_map_single(dev, key->tmp2, q_sz, DMA_BIDIRECTIONAL);
516 	if (dma_mapping_error(dev, pdb->tmp2_dma)) {
517 		dev_err(dev, "Unable to map RSA tmp2 memory\n");
518 		goto unmap_tmp1;
519 	}
520 
521 	if (edesc->src_nents > 1) {
522 		pdb->sgf |= RSA_PRIV_PDB_SGF_G;
523 		pdb->g_dma = edesc->sec4_sg_dma;
524 		sec4_sg_index += edesc->src_nents;
525 	} else {
526 		pdb->g_dma = sg_dma_address(req->src);
527 	}
528 
529 	if (edesc->dst_nents > 1) {
530 		pdb->sgf |= RSA_PRIV_PDB_SGF_F;
531 		pdb->f_dma = edesc->sec4_sg_dma +
532 			     sec4_sg_index * sizeof(struct sec4_sg_entry);
533 	} else {
534 		pdb->f_dma = sg_dma_address(req->dst);
535 	}
536 
537 	pdb->sgf |= key->n_sz;
538 	pdb->p_q_len = (q_sz << RSA_PDB_Q_SHIFT) | p_sz;
539 
540 	return 0;
541 
542 unmap_tmp1:
543 	dma_unmap_single(dev, pdb->tmp1_dma, p_sz, DMA_BIDIRECTIONAL);
544 unmap_qinv:
545 	dma_unmap_single(dev, pdb->c_dma, p_sz, DMA_TO_DEVICE);
546 unmap_dq:
547 	dma_unmap_single(dev, pdb->dq_dma, q_sz, DMA_TO_DEVICE);
548 unmap_dp:
549 	dma_unmap_single(dev, pdb->dp_dma, p_sz, DMA_TO_DEVICE);
550 unmap_q:
551 	dma_unmap_single(dev, pdb->q_dma, q_sz, DMA_TO_DEVICE);
552 unmap_p:
553 	dma_unmap_single(dev, pdb->p_dma, p_sz, DMA_TO_DEVICE);
554 
555 	return -ENOMEM;
556 }
557 
558 static int caam_rsa_enc(struct akcipher_request *req)
559 {
560 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
561 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
562 	struct caam_rsa_key *key = &ctx->key;
563 	struct device *jrdev = ctx->dev;
564 	struct rsa_edesc *edesc;
565 	int ret;
566 
567 	if (unlikely(!key->n || !key->e))
568 		return -EINVAL;
569 
570 	if (req->dst_len < key->n_sz) {
571 		req->dst_len = key->n_sz;
572 		dev_err(jrdev, "Output buffer length less than parameter n\n");
573 		return -EOVERFLOW;
574 	}
575 
576 	/* Allocate extended descriptor */
577 	edesc = rsa_edesc_alloc(req, DESC_RSA_PUB_LEN);
578 	if (IS_ERR(edesc))
579 		return PTR_ERR(edesc);
580 
581 	/* Set RSA Encrypt Protocol Data Block */
582 	ret = set_rsa_pub_pdb(req, edesc);
583 	if (ret)
584 		goto init_fail;
585 
586 	/* Initialize Job Descriptor */
587 	init_rsa_pub_desc(edesc->hw_desc, &edesc->pdb.pub);
588 
589 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_pub_done, req);
590 	if (!ret)
591 		return -EINPROGRESS;
592 
593 	rsa_pub_unmap(jrdev, edesc, req);
594 
595 init_fail:
596 	rsa_io_unmap(jrdev, edesc, req);
597 	kfree(edesc);
598 	return ret;
599 }
600 
601 static int caam_rsa_dec_priv_f1(struct akcipher_request *req)
602 {
603 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
604 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
605 	struct device *jrdev = ctx->dev;
606 	struct rsa_edesc *edesc;
607 	int ret;
608 
609 	/* Allocate extended descriptor */
610 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F1_LEN);
611 	if (IS_ERR(edesc))
612 		return PTR_ERR(edesc);
613 
614 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #1 */
615 	ret = set_rsa_priv_f1_pdb(req, edesc);
616 	if (ret)
617 		goto init_fail;
618 
619 	/* Initialize Job Descriptor */
620 	init_rsa_priv_f1_desc(edesc->hw_desc, &edesc->pdb.priv_f1);
621 
622 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f1_done, req);
623 	if (!ret)
624 		return -EINPROGRESS;
625 
626 	rsa_priv_f1_unmap(jrdev, edesc, req);
627 
628 init_fail:
629 	rsa_io_unmap(jrdev, edesc, req);
630 	kfree(edesc);
631 	return ret;
632 }
633 
634 static int caam_rsa_dec_priv_f2(struct akcipher_request *req)
635 {
636 	struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
637 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
638 	struct device *jrdev = ctx->dev;
639 	struct rsa_edesc *edesc;
640 	int ret;
641 
642 	/* Allocate extended descriptor */
643 	edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F2_LEN);
644 	if (IS_ERR(edesc))
645 		return PTR_ERR(edesc);
646 
647 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #2 */
648 	ret = set_rsa_priv_f2_pdb(req, edesc);
649 	if (ret)
650 		goto init_fail;
651 
652 	/* Initialize Job Descriptor */
653 	init_rsa_priv_f2_desc(edesc->hw_desc, &edesc->pdb.priv_f2);
654 
655 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f2_done, req);
656 	if (!ret)
657 		return -EINPROGRESS;
658 
659 	rsa_priv_f2_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_f3(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_F3_LEN);
677 	if (IS_ERR(edesc))
678 		return PTR_ERR(edesc);
679 
680 	/* Set RSA Decrypt Protocol Data Block - Private Key Form #3 */
681 	ret = set_rsa_priv_f3_pdb(req, edesc);
682 	if (ret)
683 		goto init_fail;
684 
685 	/* Initialize Job Descriptor */
686 	init_rsa_priv_f3_desc(edesc->hw_desc, &edesc->pdb.priv_f3);
687 
688 	ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f3_done, req);
689 	if (!ret)
690 		return -EINPROGRESS;
691 
692 	rsa_priv_f3_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(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 caam_rsa_key *key = &ctx->key;
705 	int ret;
706 
707 	if (unlikely(!key->n || !key->d))
708 		return -EINVAL;
709 
710 	if (req->dst_len < key->n_sz) {
711 		req->dst_len = key->n_sz;
712 		dev_err(ctx->dev, "Output buffer length less than parameter n\n");
713 		return -EOVERFLOW;
714 	}
715 
716 	if (key->priv_form == FORM3)
717 		ret = caam_rsa_dec_priv_f3(req);
718 	else if (key->priv_form == FORM2)
719 		ret = caam_rsa_dec_priv_f2(req);
720 	else
721 		ret = caam_rsa_dec_priv_f1(req);
722 
723 	return ret;
724 }
725 
726 static void caam_rsa_free_key(struct caam_rsa_key *key)
727 {
728 	kzfree(key->d);
729 	kzfree(key->p);
730 	kzfree(key->q);
731 	kzfree(key->dp);
732 	kzfree(key->dq);
733 	kzfree(key->qinv);
734 	kzfree(key->tmp1);
735 	kzfree(key->tmp2);
736 	kfree(key->e);
737 	kfree(key->n);
738 	memset(key, 0, sizeof(*key));
739 }
740 
741 static void caam_rsa_drop_leading_zeros(const u8 **ptr, size_t *nbytes)
742 {
743 	while (!**ptr && *nbytes) {
744 		(*ptr)++;
745 		(*nbytes)--;
746 	}
747 }
748 
749 /**
750  * caam_read_rsa_crt - Used for reading dP, dQ, qInv CRT members.
751  * dP, dQ and qInv could decode to less than corresponding p, q length, as the
752  * BER-encoding requires that the minimum number of bytes be used to encode the
753  * integer. dP, dQ, qInv decoded values have to be zero-padded to appropriate
754  * length.
755  *
756  * @ptr   : pointer to {dP, dQ, qInv} CRT member
757  * @nbytes: length in bytes of {dP, dQ, qInv} CRT member
758  * @dstlen: length in bytes of corresponding p or q prime factor
759  */
760 static u8 *caam_read_rsa_crt(const u8 *ptr, size_t nbytes, size_t dstlen)
761 {
762 	u8 *dst;
763 
764 	caam_rsa_drop_leading_zeros(&ptr, &nbytes);
765 	if (!nbytes)
766 		return NULL;
767 
768 	dst = kzalloc(dstlen, GFP_DMA | GFP_KERNEL);
769 	if (!dst)
770 		return NULL;
771 
772 	memcpy(dst + (dstlen - nbytes), ptr, nbytes);
773 
774 	return dst;
775 }
776 
777 /**
778  * caam_read_raw_data - Read a raw byte stream as a positive integer.
779  * The function skips buffer's leading zeros, copies the remained data
780  * to a buffer allocated in the GFP_DMA | GFP_KERNEL zone and returns
781  * the address of the new buffer.
782  *
783  * @buf   : The data to read
784  * @nbytes: The amount of data to read
785  */
786 static inline u8 *caam_read_raw_data(const u8 *buf, size_t *nbytes)
787 {
788 
789 	caam_rsa_drop_leading_zeros(&buf, nbytes);
790 	if (!*nbytes)
791 		return NULL;
792 
793 	return kmemdup(buf, *nbytes, GFP_DMA | GFP_KERNEL);
794 }
795 
796 static int caam_rsa_check_key_length(unsigned int len)
797 {
798 	if (len > 4096)
799 		return -EINVAL;
800 	return 0;
801 }
802 
803 static int caam_rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
804 				unsigned int keylen)
805 {
806 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
807 	struct rsa_key raw_key = {NULL};
808 	struct caam_rsa_key *rsa_key = &ctx->key;
809 	int ret;
810 
811 	/* Free the old RSA key if any */
812 	caam_rsa_free_key(rsa_key);
813 
814 	ret = rsa_parse_pub_key(&raw_key, key, keylen);
815 	if (ret)
816 		return ret;
817 
818 	/* Copy key in DMA zone */
819 	rsa_key->e = kzalloc(raw_key.e_sz, GFP_DMA | GFP_KERNEL);
820 	if (!rsa_key->e)
821 		goto err;
822 
823 	/*
824 	 * Skip leading zeros and copy the positive integer to a buffer
825 	 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
826 	 * expects a positive integer for the RSA modulus and uses its length as
827 	 * decryption output length.
828 	 */
829 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
830 	if (!rsa_key->n)
831 		goto err;
832 
833 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
834 		caam_rsa_free_key(rsa_key);
835 		return -EINVAL;
836 	}
837 
838 	rsa_key->e_sz = raw_key.e_sz;
839 	rsa_key->n_sz = raw_key.n_sz;
840 
841 	memcpy(rsa_key->e, raw_key.e, raw_key.e_sz);
842 
843 	return 0;
844 err:
845 	caam_rsa_free_key(rsa_key);
846 	return -ENOMEM;
847 }
848 
849 static void caam_rsa_set_priv_key_form(struct caam_rsa_ctx *ctx,
850 				       struct rsa_key *raw_key)
851 {
852 	struct caam_rsa_key *rsa_key = &ctx->key;
853 	size_t p_sz = raw_key->p_sz;
854 	size_t q_sz = raw_key->q_sz;
855 
856 	rsa_key->p = caam_read_raw_data(raw_key->p, &p_sz);
857 	if (!rsa_key->p)
858 		return;
859 	rsa_key->p_sz = p_sz;
860 
861 	rsa_key->q = caam_read_raw_data(raw_key->q, &q_sz);
862 	if (!rsa_key->q)
863 		goto free_p;
864 	rsa_key->q_sz = q_sz;
865 
866 	rsa_key->tmp1 = kzalloc(raw_key->p_sz, GFP_DMA | GFP_KERNEL);
867 	if (!rsa_key->tmp1)
868 		goto free_q;
869 
870 	rsa_key->tmp2 = kzalloc(raw_key->q_sz, GFP_DMA | GFP_KERNEL);
871 	if (!rsa_key->tmp2)
872 		goto free_tmp1;
873 
874 	rsa_key->priv_form = FORM2;
875 
876 	rsa_key->dp = caam_read_rsa_crt(raw_key->dp, raw_key->dp_sz, p_sz);
877 	if (!rsa_key->dp)
878 		goto free_tmp2;
879 
880 	rsa_key->dq = caam_read_rsa_crt(raw_key->dq, raw_key->dq_sz, q_sz);
881 	if (!rsa_key->dq)
882 		goto free_dp;
883 
884 	rsa_key->qinv = caam_read_rsa_crt(raw_key->qinv, raw_key->qinv_sz,
885 					  q_sz);
886 	if (!rsa_key->qinv)
887 		goto free_dq;
888 
889 	rsa_key->priv_form = FORM3;
890 
891 	return;
892 
893 free_dq:
894 	kzfree(rsa_key->dq);
895 free_dp:
896 	kzfree(rsa_key->dp);
897 free_tmp2:
898 	kzfree(rsa_key->tmp2);
899 free_tmp1:
900 	kzfree(rsa_key->tmp1);
901 free_q:
902 	kzfree(rsa_key->q);
903 free_p:
904 	kzfree(rsa_key->p);
905 }
906 
907 static int caam_rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
908 				 unsigned int keylen)
909 {
910 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
911 	struct rsa_key raw_key = {NULL};
912 	struct caam_rsa_key *rsa_key = &ctx->key;
913 	int ret;
914 
915 	/* Free the old RSA key if any */
916 	caam_rsa_free_key(rsa_key);
917 
918 	ret = rsa_parse_priv_key(&raw_key, key, keylen);
919 	if (ret)
920 		return ret;
921 
922 	/* Copy key in DMA zone */
923 	rsa_key->d = kzalloc(raw_key.d_sz, GFP_DMA | GFP_KERNEL);
924 	if (!rsa_key->d)
925 		goto err;
926 
927 	rsa_key->e = kzalloc(raw_key.e_sz, GFP_DMA | GFP_KERNEL);
928 	if (!rsa_key->e)
929 		goto err;
930 
931 	/*
932 	 * Skip leading zeros and copy the positive integer to a buffer
933 	 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
934 	 * expects a positive integer for the RSA modulus and uses its length as
935 	 * decryption output length.
936 	 */
937 	rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
938 	if (!rsa_key->n)
939 		goto err;
940 
941 	if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
942 		caam_rsa_free_key(rsa_key);
943 		return -EINVAL;
944 	}
945 
946 	rsa_key->d_sz = raw_key.d_sz;
947 	rsa_key->e_sz = raw_key.e_sz;
948 	rsa_key->n_sz = raw_key.n_sz;
949 
950 	memcpy(rsa_key->d, raw_key.d, raw_key.d_sz);
951 	memcpy(rsa_key->e, raw_key.e, raw_key.e_sz);
952 
953 	caam_rsa_set_priv_key_form(ctx, &raw_key);
954 
955 	return 0;
956 
957 err:
958 	caam_rsa_free_key(rsa_key);
959 	return -ENOMEM;
960 }
961 
962 static unsigned int caam_rsa_max_size(struct crypto_akcipher *tfm)
963 {
964 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
965 
966 	return ctx->key.n_sz;
967 }
968 
969 /* Per session pkc's driver context creation function */
970 static int caam_rsa_init_tfm(struct crypto_akcipher *tfm)
971 {
972 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
973 
974 	ctx->dev = caam_jr_alloc();
975 
976 	if (IS_ERR(ctx->dev)) {
977 		pr_err("Job Ring Device allocation for transform failed\n");
978 		return PTR_ERR(ctx->dev);
979 	}
980 
981 	return 0;
982 }
983 
984 /* Per session pkc's driver context cleanup function */
985 static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
986 {
987 	struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
988 	struct caam_rsa_key *key = &ctx->key;
989 
990 	caam_rsa_free_key(key);
991 	caam_jr_free(ctx->dev);
992 }
993 
994 static struct akcipher_alg caam_rsa = {
995 	.encrypt = caam_rsa_enc,
996 	.decrypt = caam_rsa_dec,
997 	.sign = caam_rsa_dec,
998 	.verify = caam_rsa_enc,
999 	.set_pub_key = caam_rsa_set_pub_key,
1000 	.set_priv_key = caam_rsa_set_priv_key,
1001 	.max_size = caam_rsa_max_size,
1002 	.init = caam_rsa_init_tfm,
1003 	.exit = caam_rsa_exit_tfm,
1004 	.reqsize = sizeof(struct caam_rsa_req_ctx),
1005 	.base = {
1006 		.cra_name = "rsa",
1007 		.cra_driver_name = "rsa-caam",
1008 		.cra_priority = 3000,
1009 		.cra_module = THIS_MODULE,
1010 		.cra_ctxsize = sizeof(struct caam_rsa_ctx),
1011 	},
1012 };
1013 
1014 /* Public Key Cryptography module initialization handler */
1015 static int __init caam_pkc_init(void)
1016 {
1017 	struct device_node *dev_node;
1018 	struct platform_device *pdev;
1019 	struct device *ctrldev;
1020 	struct caam_drv_private *priv;
1021 	u32 pk_inst;
1022 	int err;
1023 
1024 	dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0");
1025 	if (!dev_node) {
1026 		dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec4.0");
1027 		if (!dev_node)
1028 			return -ENODEV;
1029 	}
1030 
1031 	pdev = of_find_device_by_node(dev_node);
1032 	if (!pdev) {
1033 		of_node_put(dev_node);
1034 		return -ENODEV;
1035 	}
1036 
1037 	ctrldev = &pdev->dev;
1038 	priv = dev_get_drvdata(ctrldev);
1039 	of_node_put(dev_node);
1040 
1041 	/*
1042 	 * If priv is NULL, it's probably because the caam driver wasn't
1043 	 * properly initialized (e.g. RNG4 init failed). Thus, bail out here.
1044 	 */
1045 	if (!priv) {
1046 		err = -ENODEV;
1047 		goto out_put_dev;
1048 	}
1049 
1050 	/* Determine public key hardware accelerator presence. */
1051 	if (priv->era < 10)
1052 		pk_inst = (rd_reg32(&priv->ctrl->perfmon.cha_num_ls) &
1053 			   CHA_ID_LS_PK_MASK) >> CHA_ID_LS_PK_SHIFT;
1054 	else
1055 		pk_inst = rd_reg32(&priv->ctrl->vreg.pkha) & CHA_VER_NUM_MASK;
1056 
1057 	/* Do not register algorithms if PKHA is not present. */
1058 	if (!pk_inst) {
1059 		err =  -ENODEV;
1060 		goto out_put_dev;
1061 	}
1062 
1063 	err = crypto_register_akcipher(&caam_rsa);
1064 	if (err)
1065 		dev_warn(ctrldev, "%s alg registration failed\n",
1066 			 caam_rsa.base.cra_driver_name);
1067 	else
1068 		dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n");
1069 
1070 out_put_dev:
1071 	put_device(ctrldev);
1072 	return err;
1073 }
1074 
1075 static void __exit caam_pkc_exit(void)
1076 {
1077 	crypto_unregister_akcipher(&caam_rsa);
1078 }
1079 
1080 module_init(caam_pkc_init);
1081 module_exit(caam_pkc_exit);
1082 
1083 MODULE_LICENSE("Dual BSD/GPL");
1084 MODULE_DESCRIPTION("FSL CAAM support for PKC functions of crypto API");
1085 MODULE_AUTHOR("Freescale Semiconductor");
1086