1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/crypto.h>
3 #include <linux/kernel.h>
4 #include <linux/module.h>
5 #include <linux/printk.h>
6 
7 #include <crypto/aes.h>
8 #include <crypto/skcipher.h>
9 #include <crypto/scatterwalk.h>
10 #include <crypto/ctr.h>
11 #include <crypto/internal/des.h>
12 #include <crypto/xts.h>
13 
14 #include "nitrox_dev.h"
15 #include "nitrox_common.h"
16 #include "nitrox_req.h"
17 
18 struct nitrox_cipher {
19 	const char *name;
20 	enum flexi_cipher value;
21 };
22 
23 /**
24  * supported cipher list
25  */
26 static const struct nitrox_cipher flexi_cipher_table[] = {
27 	{ "null",		CIPHER_NULL },
28 	{ "cbc(des3_ede)",	CIPHER_3DES_CBC },
29 	{ "ecb(des3_ede)",	CIPHER_3DES_ECB },
30 	{ "cbc(aes)",		CIPHER_AES_CBC },
31 	{ "ecb(aes)",		CIPHER_AES_ECB },
32 	{ "cfb(aes)",		CIPHER_AES_CFB },
33 	{ "rfc3686(ctr(aes))",	CIPHER_AES_CTR },
34 	{ "xts(aes)",		CIPHER_AES_XTS },
35 	{ "cts(cbc(aes))",	CIPHER_AES_CBC_CTS },
36 	{ NULL,			CIPHER_INVALID }
37 };
38 
39 static enum flexi_cipher flexi_cipher_type(const char *name)
40 {
41 	const struct nitrox_cipher *cipher = flexi_cipher_table;
42 
43 	while (cipher->name) {
44 		if (!strcmp(cipher->name, name))
45 			break;
46 		cipher++;
47 	}
48 	return cipher->value;
49 }
50 
51 static void free_src_sglist(struct skcipher_request *skreq)
52 {
53 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
54 
55 	kfree(nkreq->src);
56 }
57 
58 static void free_dst_sglist(struct skcipher_request *skreq)
59 {
60 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
61 
62 	kfree(nkreq->dst);
63 }
64 
65 static void nitrox_skcipher_callback(void *arg, int err)
66 {
67 	struct skcipher_request *skreq = arg;
68 
69 	free_src_sglist(skreq);
70 	free_dst_sglist(skreq);
71 	if (err) {
72 		pr_err_ratelimited("request failed status 0x%0x\n", err);
73 		err = -EINVAL;
74 	}
75 
76 	skcipher_request_complete(skreq, err);
77 }
78 
79 static void nitrox_cbc_cipher_callback(void *arg, int err)
80 {
81 	struct skcipher_request *skreq = arg;
82 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
83 	struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(skreq);
84 	int ivsize = crypto_skcipher_ivsize(cipher);
85 	unsigned int start = skreq->cryptlen - ivsize;
86 
87 	if (err) {
88 		nitrox_skcipher_callback(arg, err);
89 		return;
90 	}
91 
92 	if (nkreq->creq.ctrl.s.arg == ENCRYPT) {
93 		scatterwalk_map_and_copy(skreq->iv, skreq->dst, start, ivsize,
94 					 0);
95 	} else {
96 		if (skreq->src != skreq->dst) {
97 			scatterwalk_map_and_copy(skreq->iv, skreq->src, start,
98 						 ivsize, 0);
99 		} else {
100 			memcpy(skreq->iv, nkreq->iv_out, ivsize);
101 			kfree(nkreq->iv_out);
102 		}
103 	}
104 
105 	nitrox_skcipher_callback(arg, err);
106 }
107 
108 static int nitrox_skcipher_init(struct crypto_skcipher *tfm)
109 {
110 	struct nitrox_crypto_ctx *nctx = crypto_skcipher_ctx(tfm);
111 	struct crypto_ctx_hdr *chdr;
112 
113 	/* get the first device */
114 	nctx->ndev = nitrox_get_first_device();
115 	if (!nctx->ndev)
116 		return -ENODEV;
117 
118 	/* allocate nitrox crypto context */
119 	chdr = crypto_alloc_context(nctx->ndev);
120 	if (!chdr) {
121 		nitrox_put_device(nctx->ndev);
122 		return -ENOMEM;
123 	}
124 
125 	nctx->callback = nitrox_skcipher_callback;
126 	nctx->chdr = chdr;
127 	nctx->u.ctx_handle = (uintptr_t)((u8 *)chdr->vaddr +
128 					 sizeof(struct ctx_hdr));
129 	crypto_skcipher_set_reqsize(tfm, crypto_skcipher_reqsize(tfm) +
130 				    sizeof(struct nitrox_kcrypt_request));
131 	return 0;
132 }
133 
134 static int nitrox_cbc_init(struct crypto_skcipher *tfm)
135 {
136 	int err;
137 	struct nitrox_crypto_ctx *nctx = crypto_skcipher_ctx(tfm);
138 
139 	err = nitrox_skcipher_init(tfm);
140 	if (err)
141 		return err;
142 
143 	nctx->callback = nitrox_cbc_cipher_callback;
144 	return 0;
145 }
146 
147 static void nitrox_skcipher_exit(struct crypto_skcipher *tfm)
148 {
149 	struct nitrox_crypto_ctx *nctx = crypto_skcipher_ctx(tfm);
150 
151 	/* free the nitrox crypto context */
152 	if (nctx->u.ctx_handle) {
153 		struct flexi_crypto_context *fctx = nctx->u.fctx;
154 
155 		memzero_explicit(&fctx->crypto, sizeof(struct crypto_keys));
156 		memzero_explicit(&fctx->auth, sizeof(struct auth_keys));
157 		crypto_free_context((void *)nctx->chdr);
158 	}
159 	nitrox_put_device(nctx->ndev);
160 
161 	nctx->u.ctx_handle = 0;
162 	nctx->ndev = NULL;
163 }
164 
165 static inline int nitrox_skcipher_setkey(struct crypto_skcipher *cipher,
166 					 int aes_keylen, const u8 *key,
167 					 unsigned int keylen)
168 {
169 	struct crypto_tfm *tfm = crypto_skcipher_tfm(cipher);
170 	struct nitrox_crypto_ctx *nctx = crypto_tfm_ctx(tfm);
171 	struct flexi_crypto_context *fctx;
172 	union fc_ctx_flags *flags;
173 	enum flexi_cipher cipher_type;
174 	const char *name;
175 
176 	name = crypto_tfm_alg_name(tfm);
177 	cipher_type = flexi_cipher_type(name);
178 	if (unlikely(cipher_type == CIPHER_INVALID)) {
179 		pr_err("unsupported cipher: %s\n", name);
180 		return -EINVAL;
181 	}
182 
183 	/* fill crypto context */
184 	fctx = nctx->u.fctx;
185 	flags = &fctx->flags;
186 	flags->f = 0;
187 	flags->w0.cipher_type = cipher_type;
188 	flags->w0.aes_keylen = aes_keylen;
189 	flags->w0.iv_source = IV_FROM_DPTR;
190 	flags->f = cpu_to_be64(*(u64 *)&flags->w0);
191 	/* copy the key to context */
192 	memcpy(fctx->crypto.u.key, key, keylen);
193 
194 	return 0;
195 }
196 
197 static int nitrox_aes_setkey(struct crypto_skcipher *cipher, const u8 *key,
198 			     unsigned int keylen)
199 {
200 	int aes_keylen;
201 
202 	aes_keylen = flexi_aes_keylen(keylen);
203 	if (aes_keylen < 0)
204 		return -EINVAL;
205 	return nitrox_skcipher_setkey(cipher, aes_keylen, key, keylen);
206 }
207 
208 static int alloc_src_sglist(struct skcipher_request *skreq, int ivsize)
209 {
210 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
211 	int nents = sg_nents(skreq->src) + 1;
212 	int ret;
213 
214 	/* Allocate buffer to hold IV and input scatterlist array */
215 	ret = alloc_src_req_buf(nkreq, nents, ivsize);
216 	if (ret)
217 		return ret;
218 
219 	nitrox_creq_copy_iv(nkreq->src, skreq->iv, ivsize);
220 	nitrox_creq_set_src_sg(nkreq, nents, ivsize, skreq->src,
221 			       skreq->cryptlen);
222 
223 	return 0;
224 }
225 
226 static int alloc_dst_sglist(struct skcipher_request *skreq, int ivsize)
227 {
228 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
229 	int nents = sg_nents(skreq->dst) + 3;
230 	int ret;
231 
232 	/* Allocate buffer to hold ORH, COMPLETION and output scatterlist
233 	 * array
234 	 */
235 	ret = alloc_dst_req_buf(nkreq, nents);
236 	if (ret)
237 		return ret;
238 
239 	nitrox_creq_set_orh(nkreq);
240 	nitrox_creq_set_comp(nkreq);
241 	nitrox_creq_set_dst_sg(nkreq, nents, ivsize, skreq->dst,
242 			       skreq->cryptlen);
243 
244 	return 0;
245 }
246 
247 static int nitrox_skcipher_crypt(struct skcipher_request *skreq, bool enc)
248 {
249 	struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(skreq);
250 	struct nitrox_crypto_ctx *nctx = crypto_skcipher_ctx(cipher);
251 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
252 	int ivsize = crypto_skcipher_ivsize(cipher);
253 	struct se_crypto_request *creq;
254 	int ret;
255 
256 	creq = &nkreq->creq;
257 	creq->flags = skreq->base.flags;
258 	creq->gfp = (skreq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
259 		     GFP_KERNEL : GFP_ATOMIC;
260 
261 	/* fill the request */
262 	creq->ctrl.value = 0;
263 	creq->opcode = FLEXI_CRYPTO_ENCRYPT_HMAC;
264 	creq->ctrl.s.arg = (enc ? ENCRYPT : DECRYPT);
265 	/* param0: length of the data to be encrypted */
266 	creq->gph.param0 = cpu_to_be16(skreq->cryptlen);
267 	creq->gph.param1 = 0;
268 	/* param2: encryption data offset */
269 	creq->gph.param2 = cpu_to_be16(ivsize);
270 	creq->gph.param3 = 0;
271 
272 	creq->ctx_handle = nctx->u.ctx_handle;
273 	creq->ctrl.s.ctxl = sizeof(struct flexi_crypto_context);
274 
275 	ret = alloc_src_sglist(skreq, ivsize);
276 	if (ret)
277 		return ret;
278 
279 	ret = alloc_dst_sglist(skreq, ivsize);
280 	if (ret) {
281 		free_src_sglist(skreq);
282 		return ret;
283 	}
284 
285 	/* send the crypto request */
286 	return nitrox_process_se_request(nctx->ndev, creq, nctx->callback,
287 					 skreq);
288 }
289 
290 static int nitrox_cbc_decrypt(struct skcipher_request *skreq)
291 {
292 	struct nitrox_kcrypt_request *nkreq = skcipher_request_ctx(skreq);
293 	struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(skreq);
294 	int ivsize = crypto_skcipher_ivsize(cipher);
295 	gfp_t flags = (skreq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
296 			GFP_KERNEL : GFP_ATOMIC;
297 	unsigned int start = skreq->cryptlen - ivsize;
298 
299 	if (skreq->src != skreq->dst)
300 		return nitrox_skcipher_crypt(skreq, false);
301 
302 	nkreq->iv_out = kmalloc(ivsize, flags);
303 	if (!nkreq->iv_out)
304 		return -ENOMEM;
305 
306 	scatterwalk_map_and_copy(nkreq->iv_out, skreq->src, start, ivsize, 0);
307 	return nitrox_skcipher_crypt(skreq, false);
308 }
309 
310 static int nitrox_aes_encrypt(struct skcipher_request *skreq)
311 {
312 	return nitrox_skcipher_crypt(skreq, true);
313 }
314 
315 static int nitrox_aes_decrypt(struct skcipher_request *skreq)
316 {
317 	return nitrox_skcipher_crypt(skreq, false);
318 }
319 
320 static int nitrox_3des_setkey(struct crypto_skcipher *cipher,
321 			      const u8 *key, unsigned int keylen)
322 {
323 	return verify_skcipher_des3_key(cipher, key) ?:
324 	       nitrox_skcipher_setkey(cipher, 0, key, keylen);
325 }
326 
327 static int nitrox_3des_encrypt(struct skcipher_request *skreq)
328 {
329 	return nitrox_skcipher_crypt(skreq, true);
330 }
331 
332 static int nitrox_3des_decrypt(struct skcipher_request *skreq)
333 {
334 	return nitrox_skcipher_crypt(skreq, false);
335 }
336 
337 static int nitrox_aes_xts_setkey(struct crypto_skcipher *cipher,
338 				 const u8 *key, unsigned int keylen)
339 {
340 	struct crypto_tfm *tfm = crypto_skcipher_tfm(cipher);
341 	struct nitrox_crypto_ctx *nctx = crypto_tfm_ctx(tfm);
342 	struct flexi_crypto_context *fctx;
343 	int aes_keylen, ret;
344 
345 	ret = xts_check_key(tfm, key, keylen);
346 	if (ret)
347 		return ret;
348 
349 	keylen /= 2;
350 
351 	aes_keylen = flexi_aes_keylen(keylen);
352 	if (aes_keylen < 0)
353 		return -EINVAL;
354 
355 	fctx = nctx->u.fctx;
356 	/* copy KEY2 */
357 	memcpy(fctx->auth.u.key2, (key + keylen), keylen);
358 
359 	return nitrox_skcipher_setkey(cipher, aes_keylen, key, keylen);
360 }
361 
362 static int nitrox_aes_ctr_rfc3686_setkey(struct crypto_skcipher *cipher,
363 					 const u8 *key, unsigned int keylen)
364 {
365 	struct crypto_tfm *tfm = crypto_skcipher_tfm(cipher);
366 	struct nitrox_crypto_ctx *nctx = crypto_tfm_ctx(tfm);
367 	struct flexi_crypto_context *fctx;
368 	int aes_keylen;
369 
370 	if (keylen < CTR_RFC3686_NONCE_SIZE)
371 		return -EINVAL;
372 
373 	fctx = nctx->u.fctx;
374 
375 	memcpy(fctx->crypto.iv, key + (keylen - CTR_RFC3686_NONCE_SIZE),
376 	       CTR_RFC3686_NONCE_SIZE);
377 
378 	keylen -= CTR_RFC3686_NONCE_SIZE;
379 
380 	aes_keylen = flexi_aes_keylen(keylen);
381 	if (aes_keylen < 0)
382 		return -EINVAL;
383 	return nitrox_skcipher_setkey(cipher, aes_keylen, key, keylen);
384 }
385 
386 static struct skcipher_alg nitrox_skciphers[] = { {
387 	.base = {
388 		.cra_name = "cbc(aes)",
389 		.cra_driver_name = "n5_cbc(aes)",
390 		.cra_priority = PRIO,
391 		.cra_flags = CRYPTO_ALG_ASYNC,
392 		.cra_blocksize = AES_BLOCK_SIZE,
393 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
394 		.cra_alignmask = 0,
395 		.cra_module = THIS_MODULE,
396 	},
397 	.min_keysize = AES_MIN_KEY_SIZE,
398 	.max_keysize = AES_MAX_KEY_SIZE,
399 	.ivsize = AES_BLOCK_SIZE,
400 	.setkey = nitrox_aes_setkey,
401 	.encrypt = nitrox_aes_encrypt,
402 	.decrypt = nitrox_cbc_decrypt,
403 	.init = nitrox_cbc_init,
404 	.exit = nitrox_skcipher_exit,
405 }, {
406 	.base = {
407 		.cra_name = "ecb(aes)",
408 		.cra_driver_name = "n5_ecb(aes)",
409 		.cra_priority = PRIO,
410 		.cra_flags = CRYPTO_ALG_ASYNC,
411 		.cra_blocksize = AES_BLOCK_SIZE,
412 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
413 		.cra_alignmask = 0,
414 		.cra_module = THIS_MODULE,
415 	},
416 	.min_keysize = AES_MIN_KEY_SIZE,
417 	.max_keysize = AES_MAX_KEY_SIZE,
418 	.ivsize = AES_BLOCK_SIZE,
419 	.setkey = nitrox_aes_setkey,
420 	.encrypt = nitrox_aes_encrypt,
421 	.decrypt = nitrox_aes_decrypt,
422 	.init = nitrox_skcipher_init,
423 	.exit = nitrox_skcipher_exit,
424 }, {
425 	.base = {
426 		.cra_name = "cfb(aes)",
427 		.cra_driver_name = "n5_cfb(aes)",
428 		.cra_priority = PRIO,
429 		.cra_flags = CRYPTO_ALG_ASYNC,
430 		.cra_blocksize = AES_BLOCK_SIZE,
431 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
432 		.cra_alignmask = 0,
433 		.cra_module = THIS_MODULE,
434 	},
435 	.min_keysize = AES_MIN_KEY_SIZE,
436 	.max_keysize = AES_MAX_KEY_SIZE,
437 	.ivsize = AES_BLOCK_SIZE,
438 	.setkey = nitrox_aes_setkey,
439 	.encrypt = nitrox_aes_encrypt,
440 	.decrypt = nitrox_aes_decrypt,
441 	.init = nitrox_skcipher_init,
442 	.exit = nitrox_skcipher_exit,
443 }, {
444 	.base = {
445 		.cra_name = "xts(aes)",
446 		.cra_driver_name = "n5_xts(aes)",
447 		.cra_priority = PRIO,
448 		.cra_flags = CRYPTO_ALG_ASYNC,
449 		.cra_blocksize = AES_BLOCK_SIZE,
450 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
451 		.cra_alignmask = 0,
452 		.cra_module = THIS_MODULE,
453 	},
454 	.min_keysize = 2 * AES_MIN_KEY_SIZE,
455 	.max_keysize = 2 * AES_MAX_KEY_SIZE,
456 	.ivsize = AES_BLOCK_SIZE,
457 	.setkey = nitrox_aes_xts_setkey,
458 	.encrypt = nitrox_aes_encrypt,
459 	.decrypt = nitrox_aes_decrypt,
460 	.init = nitrox_skcipher_init,
461 	.exit = nitrox_skcipher_exit,
462 }, {
463 	.base = {
464 		.cra_name = "rfc3686(ctr(aes))",
465 		.cra_driver_name = "n5_rfc3686(ctr(aes))",
466 		.cra_priority = PRIO,
467 		.cra_flags = CRYPTO_ALG_ASYNC,
468 		.cra_blocksize = 1,
469 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
470 		.cra_alignmask = 0,
471 		.cra_module = THIS_MODULE,
472 	},
473 	.min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
474 	.max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
475 	.ivsize = CTR_RFC3686_IV_SIZE,
476 	.init = nitrox_skcipher_init,
477 	.exit = nitrox_skcipher_exit,
478 	.setkey = nitrox_aes_ctr_rfc3686_setkey,
479 	.encrypt = nitrox_aes_encrypt,
480 	.decrypt = nitrox_aes_decrypt,
481 }, {
482 	.base = {
483 		.cra_name = "cts(cbc(aes))",
484 		.cra_driver_name = "n5_cts(cbc(aes))",
485 		.cra_priority = PRIO,
486 		.cra_flags = CRYPTO_ALG_ASYNC,
487 		.cra_blocksize = AES_BLOCK_SIZE,
488 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
489 		.cra_alignmask = 0,
490 		.cra_module = THIS_MODULE,
491 	},
492 	.min_keysize = AES_MIN_KEY_SIZE,
493 	.max_keysize = AES_MAX_KEY_SIZE,
494 	.ivsize = AES_BLOCK_SIZE,
495 	.setkey = nitrox_aes_setkey,
496 	.encrypt = nitrox_aes_encrypt,
497 	.decrypt = nitrox_aes_decrypt,
498 	.init = nitrox_skcipher_init,
499 	.exit = nitrox_skcipher_exit,
500 }, {
501 	.base = {
502 		.cra_name = "cbc(des3_ede)",
503 		.cra_driver_name = "n5_cbc(des3_ede)",
504 		.cra_priority = PRIO,
505 		.cra_flags = CRYPTO_ALG_ASYNC,
506 		.cra_blocksize = DES3_EDE_BLOCK_SIZE,
507 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
508 		.cra_alignmask = 0,
509 		.cra_module = THIS_MODULE,
510 	},
511 	.min_keysize = DES3_EDE_KEY_SIZE,
512 	.max_keysize = DES3_EDE_KEY_SIZE,
513 	.ivsize = DES3_EDE_BLOCK_SIZE,
514 	.setkey = nitrox_3des_setkey,
515 	.encrypt = nitrox_3des_encrypt,
516 	.decrypt = nitrox_cbc_decrypt,
517 	.init = nitrox_cbc_init,
518 	.exit = nitrox_skcipher_exit,
519 }, {
520 	.base = {
521 		.cra_name = "ecb(des3_ede)",
522 		.cra_driver_name = "n5_ecb(des3_ede)",
523 		.cra_priority = PRIO,
524 		.cra_flags = CRYPTO_ALG_ASYNC,
525 		.cra_blocksize = DES3_EDE_BLOCK_SIZE,
526 		.cra_ctxsize = sizeof(struct nitrox_crypto_ctx),
527 		.cra_alignmask = 0,
528 		.cra_module = THIS_MODULE,
529 	},
530 	.min_keysize = DES3_EDE_KEY_SIZE,
531 	.max_keysize = DES3_EDE_KEY_SIZE,
532 	.ivsize = DES3_EDE_BLOCK_SIZE,
533 	.setkey = nitrox_3des_setkey,
534 	.encrypt = nitrox_3des_encrypt,
535 	.decrypt = nitrox_3des_decrypt,
536 	.init = nitrox_skcipher_init,
537 	.exit = nitrox_skcipher_exit,
538 }
539 
540 };
541 
542 int nitrox_register_skciphers(void)
543 {
544 	return crypto_register_skciphers(nitrox_skciphers,
545 					 ARRAY_SIZE(nitrox_skciphers));
546 }
547 
548 void nitrox_unregister_skciphers(void)
549 {
550 	crypto_unregister_skciphers(nitrox_skciphers,
551 				    ARRAY_SIZE(nitrox_skciphers));
552 }
553