2 * caam - Freescale FSL CAAM support for Public Key Cryptography
4 * Copyright 2016 Freescale Semiconductor, Inc.
6 * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
7 * all the desired key parameters, input and output pointers.
14 #include "desc_constr.h"
15 #include "sg_sw_sec4.h"
18 #define DESC_RSA_PUB_LEN (2 * CAAM_CMD_SZ + sizeof(struct rsa_pub_pdb))
19 #define DESC_RSA_PRIV_F1_LEN (2 * CAAM_CMD_SZ + \
20 sizeof(struct rsa_priv_f1_pdb))
22 static void rsa_io_unmap(struct device *dev, struct rsa_edesc *edesc,
23 struct akcipher_request *req)
25 dma_unmap_sg(dev, req->dst, edesc->dst_nents, DMA_FROM_DEVICE);
26 dma_unmap_sg(dev, req->src, edesc->src_nents, DMA_TO_DEVICE);
28 if (edesc->sec4_sg_bytes)
29 dma_unmap_single(dev, edesc->sec4_sg_dma, edesc->sec4_sg_bytes,
33 static void rsa_pub_unmap(struct device *dev, struct rsa_edesc *edesc,
34 struct akcipher_request *req)
36 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
37 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
38 struct caam_rsa_key *key = &ctx->key;
39 struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
41 dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
42 dma_unmap_single(dev, pdb->e_dma, key->e_sz, DMA_TO_DEVICE);
45 static void rsa_priv_f1_unmap(struct device *dev, struct rsa_edesc *edesc,
46 struct akcipher_request *req)
48 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
49 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
50 struct caam_rsa_key *key = &ctx->key;
51 struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
53 dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
54 dma_unmap_single(dev, pdb->d_dma, key->d_sz, DMA_TO_DEVICE);
57 /* RSA Job Completion handler */
58 static void rsa_pub_done(struct device *dev, u32 *desc, u32 err, void *context)
60 struct akcipher_request *req = context;
61 struct rsa_edesc *edesc;
64 caam_jr_strstatus(dev, err);
66 edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
68 rsa_pub_unmap(dev, edesc, req);
69 rsa_io_unmap(dev, edesc, req);
72 akcipher_request_complete(req, err);
75 static void rsa_priv_f1_done(struct device *dev, u32 *desc, u32 err,
78 struct akcipher_request *req = context;
79 struct rsa_edesc *edesc;
82 caam_jr_strstatus(dev, err);
84 edesc = container_of(desc, struct rsa_edesc, hw_desc[0]);
86 rsa_priv_f1_unmap(dev, edesc, req);
87 rsa_io_unmap(dev, edesc, req);
90 akcipher_request_complete(req, err);
93 static struct rsa_edesc *rsa_edesc_alloc(struct akcipher_request *req,
96 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
97 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
98 struct device *dev = ctx->dev;
99 struct rsa_edesc *edesc;
100 gfp_t flags = (req->base.flags & (CRYPTO_TFM_REQ_MAY_BACKLOG |
101 CRYPTO_TFM_REQ_MAY_SLEEP)) ? GFP_KERNEL : GFP_ATOMIC;
103 int sec4_sg_index, sec4_sg_len = 0, sec4_sg_bytes;
104 int src_nents, dst_nents;
106 src_nents = sg_nents_for_len(req->src, req->src_len);
107 dst_nents = sg_nents_for_len(req->dst, req->dst_len);
110 sec4_sg_len = src_nents;
112 sec4_sg_len += dst_nents;
114 sec4_sg_bytes = sec4_sg_len * sizeof(struct sec4_sg_entry);
116 /* allocate space for base edesc, hw desc commands and link tables */
117 edesc = kzalloc(sizeof(*edesc) + desclen + sec4_sg_bytes,
120 return ERR_PTR(-ENOMEM);
122 sgc = dma_map_sg(dev, req->src, src_nents, DMA_TO_DEVICE);
123 if (unlikely(!sgc)) {
124 dev_err(dev, "unable to map source\n");
128 sgc = dma_map_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
129 if (unlikely(!sgc)) {
130 dev_err(dev, "unable to map destination\n");
134 edesc->sec4_sg = (void *)edesc + sizeof(*edesc) + desclen;
138 sg_to_sec4_sg_last(req->src, src_nents, edesc->sec4_sg, 0);
139 sec4_sg_index += src_nents;
142 sg_to_sec4_sg_last(req->dst, dst_nents,
143 edesc->sec4_sg + sec4_sg_index, 0);
145 /* Save nents for later use in Job Descriptor */
146 edesc->src_nents = src_nents;
147 edesc->dst_nents = dst_nents;
152 edesc->sec4_sg_dma = dma_map_single(dev, edesc->sec4_sg,
153 sec4_sg_bytes, DMA_TO_DEVICE);
154 if (dma_mapping_error(dev, edesc->sec4_sg_dma)) {
155 dev_err(dev, "unable to map S/G table\n");
159 edesc->sec4_sg_bytes = sec4_sg_bytes;
164 dma_unmap_sg(dev, req->dst, dst_nents, DMA_FROM_DEVICE);
166 dma_unmap_sg(dev, req->src, src_nents, DMA_TO_DEVICE);
169 return ERR_PTR(-ENOMEM);
172 static int set_rsa_pub_pdb(struct akcipher_request *req,
173 struct rsa_edesc *edesc)
175 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
176 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
177 struct caam_rsa_key *key = &ctx->key;
178 struct device *dev = ctx->dev;
179 struct rsa_pub_pdb *pdb = &edesc->pdb.pub;
180 int sec4_sg_index = 0;
182 pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
183 if (dma_mapping_error(dev, pdb->n_dma)) {
184 dev_err(dev, "Unable to map RSA modulus memory\n");
188 pdb->e_dma = dma_map_single(dev, key->e, key->e_sz, DMA_TO_DEVICE);
189 if (dma_mapping_error(dev, pdb->e_dma)) {
190 dev_err(dev, "Unable to map RSA public exponent memory\n");
191 dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
195 if (edesc->src_nents > 1) {
196 pdb->sgf |= RSA_PDB_SGF_F;
197 pdb->f_dma = edesc->sec4_sg_dma;
198 sec4_sg_index += edesc->src_nents;
200 pdb->f_dma = sg_dma_address(req->src);
203 if (edesc->dst_nents > 1) {
204 pdb->sgf |= RSA_PDB_SGF_G;
205 pdb->g_dma = edesc->sec4_sg_dma +
206 sec4_sg_index * sizeof(struct sec4_sg_entry);
208 pdb->g_dma = sg_dma_address(req->dst);
211 pdb->sgf |= (key->e_sz << RSA_PDB_E_SHIFT) | key->n_sz;
212 pdb->f_len = req->src_len;
217 static int set_rsa_priv_f1_pdb(struct akcipher_request *req,
218 struct rsa_edesc *edesc)
220 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
221 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
222 struct caam_rsa_key *key = &ctx->key;
223 struct device *dev = ctx->dev;
224 struct rsa_priv_f1_pdb *pdb = &edesc->pdb.priv_f1;
225 int sec4_sg_index = 0;
227 pdb->n_dma = dma_map_single(dev, key->n, key->n_sz, DMA_TO_DEVICE);
228 if (dma_mapping_error(dev, pdb->n_dma)) {
229 dev_err(dev, "Unable to map modulus memory\n");
233 pdb->d_dma = dma_map_single(dev, key->d, key->d_sz, DMA_TO_DEVICE);
234 if (dma_mapping_error(dev, pdb->d_dma)) {
235 dev_err(dev, "Unable to map RSA private exponent memory\n");
236 dma_unmap_single(dev, pdb->n_dma, key->n_sz, DMA_TO_DEVICE);
240 if (edesc->src_nents > 1) {
241 pdb->sgf |= RSA_PRIV_PDB_SGF_G;
242 pdb->g_dma = edesc->sec4_sg_dma;
243 sec4_sg_index += edesc->src_nents;
245 pdb->g_dma = sg_dma_address(req->src);
248 if (edesc->dst_nents > 1) {
249 pdb->sgf |= RSA_PRIV_PDB_SGF_F;
250 pdb->f_dma = edesc->sec4_sg_dma +
251 sec4_sg_index * sizeof(struct sec4_sg_entry);
253 pdb->f_dma = sg_dma_address(req->dst);
256 pdb->sgf |= (key->d_sz << RSA_PDB_D_SHIFT) | key->n_sz;
261 static int caam_rsa_enc(struct akcipher_request *req)
263 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
264 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
265 struct caam_rsa_key *key = &ctx->key;
266 struct device *jrdev = ctx->dev;
267 struct rsa_edesc *edesc;
270 if (unlikely(!key->n || !key->e))
273 if (req->dst_len < key->n_sz) {
274 req->dst_len = key->n_sz;
275 dev_err(jrdev, "Output buffer length less than parameter n\n");
279 /* Allocate extended descriptor */
280 edesc = rsa_edesc_alloc(req, DESC_RSA_PUB_LEN);
282 return PTR_ERR(edesc);
284 /* Set RSA Encrypt Protocol Data Block */
285 ret = set_rsa_pub_pdb(req, edesc);
289 /* Initialize Job Descriptor */
290 init_rsa_pub_desc(edesc->hw_desc, &edesc->pdb.pub);
292 ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_pub_done, req);
296 rsa_pub_unmap(jrdev, edesc, req);
299 rsa_io_unmap(jrdev, edesc, req);
304 static int caam_rsa_dec(struct akcipher_request *req)
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 *jrdev = ctx->dev;
310 struct rsa_edesc *edesc;
313 if (unlikely(!key->n || !key->d))
316 if (req->dst_len < key->n_sz) {
317 req->dst_len = key->n_sz;
318 dev_err(jrdev, "Output buffer length less than parameter n\n");
322 /* Allocate extended descriptor */
323 edesc = rsa_edesc_alloc(req, DESC_RSA_PRIV_F1_LEN);
325 return PTR_ERR(edesc);
327 /* Set RSA Decrypt Protocol Data Block - Private Key Form #1 */
328 ret = set_rsa_priv_f1_pdb(req, edesc);
332 /* Initialize Job Descriptor */
333 init_rsa_priv_f1_desc(edesc->hw_desc, &edesc->pdb.priv_f1);
335 ret = caam_jr_enqueue(jrdev, edesc->hw_desc, rsa_priv_f1_done, req);
339 rsa_priv_f1_unmap(jrdev, edesc, req);
342 rsa_io_unmap(jrdev, edesc, req);
347 static void caam_rsa_free_key(struct caam_rsa_key *key)
361 * caam_read_raw_data - Read a raw byte stream as a positive integer.
362 * The function skips buffer's leading zeros, copies the remained data
363 * to a buffer allocated in the GFP_DMA | GFP_KERNEL zone and returns
364 * the address of the new buffer.
366 * @buf : The data to read
367 * @nbytes: The amount of data to read
369 static inline u8 *caam_read_raw_data(const u8 *buf, size_t *nbytes)
373 while (!*buf && *nbytes) {
378 val = kzalloc(*nbytes, GFP_DMA | GFP_KERNEL);
382 memcpy(val, buf, *nbytes);
387 static int caam_rsa_check_key_length(unsigned int len)
394 static int caam_rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key,
397 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
398 struct rsa_key raw_key = {NULL};
399 struct caam_rsa_key *rsa_key = &ctx->key;
402 /* Free the old RSA key if any */
403 caam_rsa_free_key(rsa_key);
405 ret = rsa_parse_pub_key(&raw_key, key, keylen);
409 /* Copy key in DMA zone */
410 rsa_key->e = kzalloc(raw_key.e_sz, GFP_DMA | GFP_KERNEL);
415 * Skip leading zeros and copy the positive integer to a buffer
416 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
417 * expects a positive integer for the RSA modulus and uses its length as
418 * decryption output length.
420 rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
424 if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
425 caam_rsa_free_key(rsa_key);
429 rsa_key->e_sz = raw_key.e_sz;
430 rsa_key->n_sz = raw_key.n_sz;
432 memcpy(rsa_key->e, raw_key.e, raw_key.e_sz);
436 caam_rsa_free_key(rsa_key);
440 static int caam_rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key,
443 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
444 struct rsa_key raw_key = {NULL};
445 struct caam_rsa_key *rsa_key = &ctx->key;
448 /* Free the old RSA key if any */
449 caam_rsa_free_key(rsa_key);
451 ret = rsa_parse_priv_key(&raw_key, key, keylen);
455 /* Copy key in DMA zone */
456 rsa_key->d = kzalloc(raw_key.d_sz, GFP_DMA | GFP_KERNEL);
460 rsa_key->e = kzalloc(raw_key.e_sz, GFP_DMA | GFP_KERNEL);
465 * Skip leading zeros and copy the positive integer to a buffer
466 * allocated in the GFP_DMA | GFP_KERNEL zone. The decryption descriptor
467 * expects a positive integer for the RSA modulus and uses its length as
468 * decryption output length.
470 rsa_key->n = caam_read_raw_data(raw_key.n, &raw_key.n_sz);
474 if (caam_rsa_check_key_length(raw_key.n_sz << 3)) {
475 caam_rsa_free_key(rsa_key);
479 rsa_key->d_sz = raw_key.d_sz;
480 rsa_key->e_sz = raw_key.e_sz;
481 rsa_key->n_sz = raw_key.n_sz;
483 memcpy(rsa_key->d, raw_key.d, raw_key.d_sz);
484 memcpy(rsa_key->e, raw_key.e, raw_key.e_sz);
489 caam_rsa_free_key(rsa_key);
493 static int caam_rsa_max_size(struct crypto_akcipher *tfm)
495 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
496 struct caam_rsa_key *key = &ctx->key;
498 return (key->n) ? key->n_sz : -EINVAL;
501 /* Per session pkc's driver context creation function */
502 static int caam_rsa_init_tfm(struct crypto_akcipher *tfm)
504 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
506 ctx->dev = caam_jr_alloc();
508 if (IS_ERR(ctx->dev)) {
509 dev_err(ctx->dev, "Job Ring Device allocation for transform failed\n");
510 return PTR_ERR(ctx->dev);
516 /* Per session pkc's driver context cleanup function */
517 static void caam_rsa_exit_tfm(struct crypto_akcipher *tfm)
519 struct caam_rsa_ctx *ctx = akcipher_tfm_ctx(tfm);
520 struct caam_rsa_key *key = &ctx->key;
522 caam_rsa_free_key(key);
523 caam_jr_free(ctx->dev);
526 static struct akcipher_alg caam_rsa = {
527 .encrypt = caam_rsa_enc,
528 .decrypt = caam_rsa_dec,
529 .sign = caam_rsa_dec,
530 .verify = caam_rsa_enc,
531 .set_pub_key = caam_rsa_set_pub_key,
532 .set_priv_key = caam_rsa_set_priv_key,
533 .max_size = caam_rsa_max_size,
534 .init = caam_rsa_init_tfm,
535 .exit = caam_rsa_exit_tfm,
538 .cra_driver_name = "rsa-caam",
539 .cra_priority = 3000,
540 .cra_module = THIS_MODULE,
541 .cra_ctxsize = sizeof(struct caam_rsa_ctx),
545 /* Public Key Cryptography module initialization handler */
546 static int __init caam_pkc_init(void)
548 struct device_node *dev_node;
549 struct platform_device *pdev;
550 struct device *ctrldev;
551 struct caam_drv_private *priv;
552 u32 cha_inst, pk_inst;
555 dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec-v4.0");
557 dev_node = of_find_compatible_node(NULL, NULL, "fsl,sec4.0");
562 pdev = of_find_device_by_node(dev_node);
564 of_node_put(dev_node);
568 ctrldev = &pdev->dev;
569 priv = dev_get_drvdata(ctrldev);
570 of_node_put(dev_node);
573 * If priv is NULL, it's probably because the caam driver wasn't
574 * properly initialized (e.g. RNG4 init failed). Thus, bail out here.
579 /* Determine public key hardware accelerator presence. */
580 cha_inst = rd_reg32(&priv->ctrl->perfmon.cha_num_ls);
581 pk_inst = (cha_inst & CHA_ID_LS_PK_MASK) >> CHA_ID_LS_PK_SHIFT;
583 /* Do not register algorithms if PKHA is not present. */
587 err = crypto_register_akcipher(&caam_rsa);
589 dev_warn(ctrldev, "%s alg registration failed\n",
590 caam_rsa.base.cra_driver_name);
592 dev_info(ctrldev, "caam pkc algorithms registered in /proc/crypto\n");
597 static void __exit caam_pkc_exit(void)
599 crypto_unregister_akcipher(&caam_rsa);
602 module_init(caam_pkc_init);
603 module_exit(caam_pkc_exit);
605 MODULE_LICENSE("Dual BSD/GPL");
606 MODULE_DESCRIPTION("FSL CAAM support for PKC functions of crypto API");
607 MODULE_AUTHOR("Freescale Semiconductor");