1 // SPDX-License-Identifier: GPL-2.0-or-later
2  /* Algorithms supported by virtio crypto device
3   *
4   * Authors: Gonglei <arei.gonglei@huawei.com>
5   *
6   * Copyright 2016 HUAWEI TECHNOLOGIES CO., LTD.
7   */
8 
9 #include <linux/scatterlist.h>
10 #include <crypto/algapi.h>
11 #include <crypto/internal/skcipher.h>
12 #include <linux/err.h>
13 #include <crypto/scatterwalk.h>
14 #include <linux/atomic.h>
15 
16 #include <uapi/linux/virtio_crypto.h>
17 #include "virtio_crypto_common.h"
18 
19 
20 struct virtio_crypto_skcipher_ctx {
21 	struct crypto_engine_ctx enginectx;
22 	struct virtio_crypto *vcrypto;
23 	struct crypto_skcipher *tfm;
24 
25 	struct virtio_crypto_sym_session_info enc_sess_info;
26 	struct virtio_crypto_sym_session_info dec_sess_info;
27 };
28 
29 struct virtio_crypto_sym_request {
30 	struct virtio_crypto_request base;
31 
32 	/* Cipher or aead */
33 	uint32_t type;
34 	struct virtio_crypto_skcipher_ctx *skcipher_ctx;
35 	struct skcipher_request *skcipher_req;
36 	uint8_t *iv;
37 	/* Encryption? */
38 	bool encrypt;
39 };
40 
41 struct virtio_crypto_algo {
42 	uint32_t algonum;
43 	uint32_t service;
44 	unsigned int active_devs;
45 	struct skcipher_alg algo;
46 };
47 
48 /*
49  * The algs_lock protects the below global virtio_crypto_active_devs
50  * and crypto algorithms registion.
51  */
52 static DEFINE_MUTEX(algs_lock);
53 static void virtio_crypto_skcipher_finalize_req(
54 	struct virtio_crypto_sym_request *vc_sym_req,
55 	struct skcipher_request *req,
56 	int err);
57 
virtio_crypto_dataq_sym_callback(struct virtio_crypto_request * vc_req,int len)58 static void virtio_crypto_dataq_sym_callback
59 		(struct virtio_crypto_request *vc_req, int len)
60 {
61 	struct virtio_crypto_sym_request *vc_sym_req =
62 		container_of(vc_req, struct virtio_crypto_sym_request, base);
63 	struct skcipher_request *ablk_req;
64 	int error;
65 
66 	/* Finish the encrypt or decrypt process */
67 	if (vc_sym_req->type == VIRTIO_CRYPTO_SYM_OP_CIPHER) {
68 		switch (vc_req->status) {
69 		case VIRTIO_CRYPTO_OK:
70 			error = 0;
71 			break;
72 		case VIRTIO_CRYPTO_INVSESS:
73 		case VIRTIO_CRYPTO_ERR:
74 			error = -EINVAL;
75 			break;
76 		case VIRTIO_CRYPTO_BADMSG:
77 			error = -EBADMSG;
78 			break;
79 		default:
80 			error = -EIO;
81 			break;
82 		}
83 		ablk_req = vc_sym_req->skcipher_req;
84 		virtio_crypto_skcipher_finalize_req(vc_sym_req,
85 							ablk_req, error);
86 	}
87 }
88 
virtio_crypto_alg_sg_nents_length(struct scatterlist * sg)89 static u64 virtio_crypto_alg_sg_nents_length(struct scatterlist *sg)
90 {
91 	u64 total = 0;
92 
93 	for (total = 0; sg; sg = sg_next(sg))
94 		total += sg->length;
95 
96 	return total;
97 }
98 
99 static int
virtio_crypto_alg_validate_key(int key_len,uint32_t * alg)100 virtio_crypto_alg_validate_key(int key_len, uint32_t *alg)
101 {
102 	switch (key_len) {
103 	case AES_KEYSIZE_128:
104 	case AES_KEYSIZE_192:
105 	case AES_KEYSIZE_256:
106 		*alg = VIRTIO_CRYPTO_CIPHER_AES_CBC;
107 		break;
108 	default:
109 		return -EINVAL;
110 	}
111 	return 0;
112 }
113 
virtio_crypto_alg_skcipher_init_session(struct virtio_crypto_skcipher_ctx * ctx,uint32_t alg,const uint8_t * key,unsigned int keylen,int encrypt)114 static int virtio_crypto_alg_skcipher_init_session(
115 		struct virtio_crypto_skcipher_ctx *ctx,
116 		uint32_t alg, const uint8_t *key,
117 		unsigned int keylen,
118 		int encrypt)
119 {
120 	struct scatterlist outhdr, key_sg, inhdr, *sgs[3];
121 	unsigned int tmp;
122 	struct virtio_crypto *vcrypto = ctx->vcrypto;
123 	int op = encrypt ? VIRTIO_CRYPTO_OP_ENCRYPT : VIRTIO_CRYPTO_OP_DECRYPT;
124 	int err;
125 	unsigned int num_out = 0, num_in = 0;
126 
127 	/*
128 	 * Avoid to do DMA from the stack, switch to using
129 	 * dynamically-allocated for the key
130 	 */
131 	uint8_t *cipher_key = kmemdup(key, keylen, GFP_ATOMIC);
132 
133 	if (!cipher_key)
134 		return -ENOMEM;
135 
136 	spin_lock(&vcrypto->ctrl_lock);
137 	/* Pad ctrl header */
138 	vcrypto->ctrl.header.opcode =
139 		cpu_to_le32(VIRTIO_CRYPTO_CIPHER_CREATE_SESSION);
140 	vcrypto->ctrl.header.algo = cpu_to_le32(alg);
141 	/* Set the default dataqueue id to 0 */
142 	vcrypto->ctrl.header.queue_id = 0;
143 
144 	vcrypto->input.status = cpu_to_le32(VIRTIO_CRYPTO_ERR);
145 	/* Pad cipher's parameters */
146 	vcrypto->ctrl.u.sym_create_session.op_type =
147 		cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
148 	vcrypto->ctrl.u.sym_create_session.u.cipher.para.algo =
149 		vcrypto->ctrl.header.algo;
150 	vcrypto->ctrl.u.sym_create_session.u.cipher.para.keylen =
151 		cpu_to_le32(keylen);
152 	vcrypto->ctrl.u.sym_create_session.u.cipher.para.op =
153 		cpu_to_le32(op);
154 
155 	sg_init_one(&outhdr, &vcrypto->ctrl, sizeof(vcrypto->ctrl));
156 	sgs[num_out++] = &outhdr;
157 
158 	/* Set key */
159 	sg_init_one(&key_sg, cipher_key, keylen);
160 	sgs[num_out++] = &key_sg;
161 
162 	/* Return status and session id back */
163 	sg_init_one(&inhdr, &vcrypto->input, sizeof(vcrypto->input));
164 	sgs[num_out + num_in++] = &inhdr;
165 
166 	err = virtqueue_add_sgs(vcrypto->ctrl_vq, sgs, num_out,
167 				num_in, vcrypto, GFP_ATOMIC);
168 	if (err < 0) {
169 		spin_unlock(&vcrypto->ctrl_lock);
170 		kfree_sensitive(cipher_key);
171 		return err;
172 	}
173 	virtqueue_kick(vcrypto->ctrl_vq);
174 
175 	/*
176 	 * Trapping into the hypervisor, so the request should be
177 	 * handled immediately.
178 	 */
179 	while (!virtqueue_get_buf(vcrypto->ctrl_vq, &tmp) &&
180 	       !virtqueue_is_broken(vcrypto->ctrl_vq))
181 		cpu_relax();
182 
183 	if (le32_to_cpu(vcrypto->input.status) != VIRTIO_CRYPTO_OK) {
184 		spin_unlock(&vcrypto->ctrl_lock);
185 		pr_err("virtio_crypto: Create session failed status: %u\n",
186 			le32_to_cpu(vcrypto->input.status));
187 		kfree_sensitive(cipher_key);
188 		return -EINVAL;
189 	}
190 
191 	if (encrypt)
192 		ctx->enc_sess_info.session_id =
193 			le64_to_cpu(vcrypto->input.session_id);
194 	else
195 		ctx->dec_sess_info.session_id =
196 			le64_to_cpu(vcrypto->input.session_id);
197 
198 	spin_unlock(&vcrypto->ctrl_lock);
199 
200 	kfree_sensitive(cipher_key);
201 	return 0;
202 }
203 
virtio_crypto_alg_skcipher_close_session(struct virtio_crypto_skcipher_ctx * ctx,int encrypt)204 static int virtio_crypto_alg_skcipher_close_session(
205 		struct virtio_crypto_skcipher_ctx *ctx,
206 		int encrypt)
207 {
208 	struct scatterlist outhdr, status_sg, *sgs[2];
209 	unsigned int tmp;
210 	struct virtio_crypto_destroy_session_req *destroy_session;
211 	struct virtio_crypto *vcrypto = ctx->vcrypto;
212 	int err;
213 	unsigned int num_out = 0, num_in = 0;
214 
215 	spin_lock(&vcrypto->ctrl_lock);
216 	vcrypto->ctrl_status.status = VIRTIO_CRYPTO_ERR;
217 	/* Pad ctrl header */
218 	vcrypto->ctrl.header.opcode =
219 		cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DESTROY_SESSION);
220 	/* Set the default virtqueue id to 0 */
221 	vcrypto->ctrl.header.queue_id = 0;
222 
223 	destroy_session = &vcrypto->ctrl.u.destroy_session;
224 
225 	if (encrypt)
226 		destroy_session->session_id =
227 			cpu_to_le64(ctx->enc_sess_info.session_id);
228 	else
229 		destroy_session->session_id =
230 			cpu_to_le64(ctx->dec_sess_info.session_id);
231 
232 	sg_init_one(&outhdr, &vcrypto->ctrl, sizeof(vcrypto->ctrl));
233 	sgs[num_out++] = &outhdr;
234 
235 	/* Return status and session id back */
236 	sg_init_one(&status_sg, &vcrypto->ctrl_status.status,
237 		sizeof(vcrypto->ctrl_status.status));
238 	sgs[num_out + num_in++] = &status_sg;
239 
240 	err = virtqueue_add_sgs(vcrypto->ctrl_vq, sgs, num_out,
241 			num_in, vcrypto, GFP_ATOMIC);
242 	if (err < 0) {
243 		spin_unlock(&vcrypto->ctrl_lock);
244 		return err;
245 	}
246 	virtqueue_kick(vcrypto->ctrl_vq);
247 
248 	while (!virtqueue_get_buf(vcrypto->ctrl_vq, &tmp) &&
249 	       !virtqueue_is_broken(vcrypto->ctrl_vq))
250 		cpu_relax();
251 
252 	if (vcrypto->ctrl_status.status != VIRTIO_CRYPTO_OK) {
253 		spin_unlock(&vcrypto->ctrl_lock);
254 		pr_err("virtio_crypto: Close session failed status: %u, session_id: 0x%llx\n",
255 			vcrypto->ctrl_status.status,
256 			destroy_session->session_id);
257 
258 		return -EINVAL;
259 	}
260 	spin_unlock(&vcrypto->ctrl_lock);
261 
262 	return 0;
263 }
264 
virtio_crypto_alg_skcipher_init_sessions(struct virtio_crypto_skcipher_ctx * ctx,const uint8_t * key,unsigned int keylen)265 static int virtio_crypto_alg_skcipher_init_sessions(
266 		struct virtio_crypto_skcipher_ctx *ctx,
267 		const uint8_t *key, unsigned int keylen)
268 {
269 	uint32_t alg;
270 	int ret;
271 	struct virtio_crypto *vcrypto = ctx->vcrypto;
272 
273 	if (keylen > vcrypto->max_cipher_key_len) {
274 		pr_err("virtio_crypto: the key is too long\n");
275 		return -EINVAL;
276 	}
277 
278 	if (virtio_crypto_alg_validate_key(keylen, &alg))
279 		return -EINVAL;
280 
281 	/* Create encryption session */
282 	ret = virtio_crypto_alg_skcipher_init_session(ctx,
283 			alg, key, keylen, 1);
284 	if (ret)
285 		return ret;
286 	/* Create decryption session */
287 	ret = virtio_crypto_alg_skcipher_init_session(ctx,
288 			alg, key, keylen, 0);
289 	if (ret) {
290 		virtio_crypto_alg_skcipher_close_session(ctx, 1);
291 		return ret;
292 	}
293 	return 0;
294 }
295 
296 /* Note: kernel crypto API realization */
virtio_crypto_skcipher_setkey(struct crypto_skcipher * tfm,const uint8_t * key,unsigned int keylen)297 static int virtio_crypto_skcipher_setkey(struct crypto_skcipher *tfm,
298 					 const uint8_t *key,
299 					 unsigned int keylen)
300 {
301 	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
302 	uint32_t alg;
303 	int ret;
304 
305 	ret = virtio_crypto_alg_validate_key(keylen, &alg);
306 	if (ret)
307 		return ret;
308 
309 	if (!ctx->vcrypto) {
310 		/* New key */
311 		int node = virtio_crypto_get_current_node();
312 		struct virtio_crypto *vcrypto =
313 				      virtcrypto_get_dev_node(node,
314 				      VIRTIO_CRYPTO_SERVICE_CIPHER, alg);
315 		if (!vcrypto) {
316 			pr_err("virtio_crypto: Could not find a virtio device in the system or unsupported algo\n");
317 			return -ENODEV;
318 		}
319 
320 		ctx->vcrypto = vcrypto;
321 	} else {
322 		/* Rekeying, we should close the created sessions previously */
323 		virtio_crypto_alg_skcipher_close_session(ctx, 1);
324 		virtio_crypto_alg_skcipher_close_session(ctx, 0);
325 	}
326 
327 	ret = virtio_crypto_alg_skcipher_init_sessions(ctx, key, keylen);
328 	if (ret) {
329 		virtcrypto_dev_put(ctx->vcrypto);
330 		ctx->vcrypto = NULL;
331 
332 		return ret;
333 	}
334 
335 	return 0;
336 }
337 
338 static int
__virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request * vc_sym_req,struct skcipher_request * req,struct data_queue * data_vq)339 __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
340 		struct skcipher_request *req,
341 		struct data_queue *data_vq)
342 {
343 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
344 	struct virtio_crypto_skcipher_ctx *ctx = vc_sym_req->skcipher_ctx;
345 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
346 	unsigned int ivsize = crypto_skcipher_ivsize(tfm);
347 	struct virtio_crypto *vcrypto = ctx->vcrypto;
348 	struct virtio_crypto_op_data_req *req_data;
349 	int src_nents, dst_nents;
350 	int err;
351 	unsigned long flags;
352 	struct scatterlist outhdr, iv_sg, status_sg, **sgs;
353 	u64 dst_len;
354 	unsigned int num_out = 0, num_in = 0;
355 	int sg_total;
356 	uint8_t *iv;
357 	struct scatterlist *sg;
358 
359 	src_nents = sg_nents_for_len(req->src, req->cryptlen);
360 	if (src_nents < 0) {
361 		pr_err("Invalid number of src SG.\n");
362 		return src_nents;
363 	}
364 
365 	dst_nents = sg_nents(req->dst);
366 
367 	pr_debug("virtio_crypto: Number of sgs (src_nents: %d, dst_nents: %d)\n",
368 			src_nents, dst_nents);
369 
370 	/* Why 3?  outhdr + iv + inhdr */
371 	sg_total = src_nents + dst_nents + 3;
372 	sgs = kcalloc_node(sg_total, sizeof(*sgs), GFP_KERNEL,
373 				dev_to_node(&vcrypto->vdev->dev));
374 	if (!sgs)
375 		return -ENOMEM;
376 
377 	req_data = kzalloc_node(sizeof(*req_data), GFP_KERNEL,
378 				dev_to_node(&vcrypto->vdev->dev));
379 	if (!req_data) {
380 		kfree(sgs);
381 		return -ENOMEM;
382 	}
383 
384 	vc_req->req_data = req_data;
385 	vc_sym_req->type = VIRTIO_CRYPTO_SYM_OP_CIPHER;
386 	/* Head of operation */
387 	if (vc_sym_req->encrypt) {
388 		req_data->header.session_id =
389 			cpu_to_le64(ctx->enc_sess_info.session_id);
390 		req_data->header.opcode =
391 			cpu_to_le32(VIRTIO_CRYPTO_CIPHER_ENCRYPT);
392 	} else {
393 		req_data->header.session_id =
394 			cpu_to_le64(ctx->dec_sess_info.session_id);
395 		req_data->header.opcode =
396 			cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DECRYPT);
397 	}
398 	req_data->u.sym_req.op_type = cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
399 	req_data->u.sym_req.u.cipher.para.iv_len = cpu_to_le32(ivsize);
400 	req_data->u.sym_req.u.cipher.para.src_data_len =
401 			cpu_to_le32(req->cryptlen);
402 
403 	dst_len = virtio_crypto_alg_sg_nents_length(req->dst);
404 	if (unlikely(dst_len > U32_MAX)) {
405 		pr_err("virtio_crypto: The dst_len is beyond U32_MAX\n");
406 		err = -EINVAL;
407 		goto free;
408 	}
409 
410 	dst_len = min_t(unsigned int, req->cryptlen, dst_len);
411 	pr_debug("virtio_crypto: src_len: %u, dst_len: %llu\n",
412 			req->cryptlen, dst_len);
413 
414 	if (unlikely(req->cryptlen + dst_len + ivsize +
415 		sizeof(vc_req->status) > vcrypto->max_size)) {
416 		pr_err("virtio_crypto: The length is too big\n");
417 		err = -EINVAL;
418 		goto free;
419 	}
420 
421 	req_data->u.sym_req.u.cipher.para.dst_data_len =
422 			cpu_to_le32((uint32_t)dst_len);
423 
424 	/* Outhdr */
425 	sg_init_one(&outhdr, req_data, sizeof(*req_data));
426 	sgs[num_out++] = &outhdr;
427 
428 	/* IV */
429 
430 	/*
431 	 * Avoid to do DMA from the stack, switch to using
432 	 * dynamically-allocated for the IV
433 	 */
434 	iv = kzalloc_node(ivsize, GFP_ATOMIC,
435 				dev_to_node(&vcrypto->vdev->dev));
436 	if (!iv) {
437 		err = -ENOMEM;
438 		goto free;
439 	}
440 	memcpy(iv, req->iv, ivsize);
441 	if (!vc_sym_req->encrypt)
442 		scatterwalk_map_and_copy(req->iv, req->src,
443 					 req->cryptlen - AES_BLOCK_SIZE,
444 					 AES_BLOCK_SIZE, 0);
445 
446 	sg_init_one(&iv_sg, iv, ivsize);
447 	sgs[num_out++] = &iv_sg;
448 	vc_sym_req->iv = iv;
449 
450 	/* Source data */
451 	for (sg = req->src; src_nents; sg = sg_next(sg), src_nents--)
452 		sgs[num_out++] = sg;
453 
454 	/* Destination data */
455 	for (sg = req->dst; sg; sg = sg_next(sg))
456 		sgs[num_out + num_in++] = sg;
457 
458 	/* Status */
459 	sg_init_one(&status_sg, &vc_req->status, sizeof(vc_req->status));
460 	sgs[num_out + num_in++] = &status_sg;
461 
462 	vc_req->sgs = sgs;
463 
464 	spin_lock_irqsave(&data_vq->lock, flags);
465 	err = virtqueue_add_sgs(data_vq->vq, sgs, num_out,
466 				num_in, vc_req, GFP_ATOMIC);
467 	virtqueue_kick(data_vq->vq);
468 	spin_unlock_irqrestore(&data_vq->lock, flags);
469 	if (unlikely(err < 0))
470 		goto free_iv;
471 
472 	return 0;
473 
474 free_iv:
475 	kfree_sensitive(iv);
476 free:
477 	kfree_sensitive(req_data);
478 	kfree(sgs);
479 	return err;
480 }
481 
virtio_crypto_skcipher_encrypt(struct skcipher_request * req)482 static int virtio_crypto_skcipher_encrypt(struct skcipher_request *req)
483 {
484 	struct crypto_skcipher *atfm = crypto_skcipher_reqtfm(req);
485 	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(atfm);
486 	struct virtio_crypto_sym_request *vc_sym_req =
487 				skcipher_request_ctx(req);
488 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
489 	struct virtio_crypto *vcrypto = ctx->vcrypto;
490 	/* Use the first data virtqueue as default */
491 	struct data_queue *data_vq = &vcrypto->data_vq[0];
492 
493 	if (!req->cryptlen)
494 		return 0;
495 	if (req->cryptlen % AES_BLOCK_SIZE)
496 		return -EINVAL;
497 
498 	vc_req->dataq = data_vq;
499 	vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
500 	vc_sym_req->skcipher_ctx = ctx;
501 	vc_sym_req->skcipher_req = req;
502 	vc_sym_req->encrypt = true;
503 
504 	return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
505 }
506 
virtio_crypto_skcipher_decrypt(struct skcipher_request * req)507 static int virtio_crypto_skcipher_decrypt(struct skcipher_request *req)
508 {
509 	struct crypto_skcipher *atfm = crypto_skcipher_reqtfm(req);
510 	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(atfm);
511 	struct virtio_crypto_sym_request *vc_sym_req =
512 				skcipher_request_ctx(req);
513 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
514 	struct virtio_crypto *vcrypto = ctx->vcrypto;
515 	/* Use the first data virtqueue as default */
516 	struct data_queue *data_vq = &vcrypto->data_vq[0];
517 
518 	if (!req->cryptlen)
519 		return 0;
520 	if (req->cryptlen % AES_BLOCK_SIZE)
521 		return -EINVAL;
522 
523 	vc_req->dataq = data_vq;
524 	vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
525 	vc_sym_req->skcipher_ctx = ctx;
526 	vc_sym_req->skcipher_req = req;
527 	vc_sym_req->encrypt = false;
528 
529 	return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
530 }
531 
virtio_crypto_skcipher_init(struct crypto_skcipher * tfm)532 static int virtio_crypto_skcipher_init(struct crypto_skcipher *tfm)
533 {
534 	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
535 
536 	crypto_skcipher_set_reqsize(tfm, sizeof(struct virtio_crypto_sym_request));
537 	ctx->tfm = tfm;
538 
539 	ctx->enginectx.op.do_one_request = virtio_crypto_skcipher_crypt_req;
540 	ctx->enginectx.op.prepare_request = NULL;
541 	ctx->enginectx.op.unprepare_request = NULL;
542 	return 0;
543 }
544 
virtio_crypto_skcipher_exit(struct crypto_skcipher * tfm)545 static void virtio_crypto_skcipher_exit(struct crypto_skcipher *tfm)
546 {
547 	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
548 
549 	if (!ctx->vcrypto)
550 		return;
551 
552 	virtio_crypto_alg_skcipher_close_session(ctx, 1);
553 	virtio_crypto_alg_skcipher_close_session(ctx, 0);
554 	virtcrypto_dev_put(ctx->vcrypto);
555 	ctx->vcrypto = NULL;
556 }
557 
virtio_crypto_skcipher_crypt_req(struct crypto_engine * engine,void * vreq)558 int virtio_crypto_skcipher_crypt_req(
559 	struct crypto_engine *engine, void *vreq)
560 {
561 	struct skcipher_request *req = container_of(vreq, struct skcipher_request, base);
562 	struct virtio_crypto_sym_request *vc_sym_req =
563 				skcipher_request_ctx(req);
564 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
565 	struct data_queue *data_vq = vc_req->dataq;
566 	int ret;
567 
568 	ret = __virtio_crypto_skcipher_do_req(vc_sym_req, req, data_vq);
569 	if (ret < 0)
570 		return ret;
571 
572 	virtqueue_kick(data_vq->vq);
573 
574 	return 0;
575 }
576 
virtio_crypto_skcipher_finalize_req(struct virtio_crypto_sym_request * vc_sym_req,struct skcipher_request * req,int err)577 static void virtio_crypto_skcipher_finalize_req(
578 	struct virtio_crypto_sym_request *vc_sym_req,
579 	struct skcipher_request *req,
580 	int err)
581 {
582 	if (vc_sym_req->encrypt)
583 		scatterwalk_map_and_copy(req->iv, req->dst,
584 					 req->cryptlen - AES_BLOCK_SIZE,
585 					 AES_BLOCK_SIZE, 0);
586 	kfree_sensitive(vc_sym_req->iv);
587 	virtcrypto_clear_request(&vc_sym_req->base);
588 
589 	crypto_finalize_skcipher_request(vc_sym_req->base.dataq->engine,
590 					   req, err);
591 }
592 
593 static struct virtio_crypto_algo virtio_crypto_algs[] = { {
594 	.algonum = VIRTIO_CRYPTO_CIPHER_AES_CBC,
595 	.service = VIRTIO_CRYPTO_SERVICE_CIPHER,
596 	.algo = {
597 		.base.cra_name		= "cbc(aes)",
598 		.base.cra_driver_name	= "virtio_crypto_aes_cbc",
599 		.base.cra_priority	= 150,
600 		.base.cra_flags		= CRYPTO_ALG_ASYNC |
601 					  CRYPTO_ALG_ALLOCATES_MEMORY,
602 		.base.cra_blocksize	= AES_BLOCK_SIZE,
603 		.base.cra_ctxsize	= sizeof(struct virtio_crypto_skcipher_ctx),
604 		.base.cra_module	= THIS_MODULE,
605 		.init			= virtio_crypto_skcipher_init,
606 		.exit			= virtio_crypto_skcipher_exit,
607 		.setkey			= virtio_crypto_skcipher_setkey,
608 		.decrypt		= virtio_crypto_skcipher_decrypt,
609 		.encrypt		= virtio_crypto_skcipher_encrypt,
610 		.min_keysize		= AES_MIN_KEY_SIZE,
611 		.max_keysize		= AES_MAX_KEY_SIZE,
612 		.ivsize			= AES_BLOCK_SIZE,
613 	},
614 } };
615 
virtio_crypto_algs_register(struct virtio_crypto * vcrypto)616 int virtio_crypto_algs_register(struct virtio_crypto *vcrypto)
617 {
618 	int ret = 0;
619 	int i = 0;
620 
621 	mutex_lock(&algs_lock);
622 
623 	for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
624 
625 		uint32_t service = virtio_crypto_algs[i].service;
626 		uint32_t algonum = virtio_crypto_algs[i].algonum;
627 
628 		if (!virtcrypto_algo_is_supported(vcrypto, service, algonum))
629 			continue;
630 
631 		if (virtio_crypto_algs[i].active_devs == 0) {
632 			ret = crypto_register_skcipher(&virtio_crypto_algs[i].algo);
633 			if (ret)
634 				goto unlock;
635 		}
636 
637 		virtio_crypto_algs[i].active_devs++;
638 		dev_info(&vcrypto->vdev->dev, "Registered algo %s\n",
639 			 virtio_crypto_algs[i].algo.base.cra_name);
640 	}
641 
642 unlock:
643 	mutex_unlock(&algs_lock);
644 	return ret;
645 }
646 
virtio_crypto_algs_unregister(struct virtio_crypto * vcrypto)647 void virtio_crypto_algs_unregister(struct virtio_crypto *vcrypto)
648 {
649 	int i = 0;
650 
651 	mutex_lock(&algs_lock);
652 
653 	for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
654 
655 		uint32_t service = virtio_crypto_algs[i].service;
656 		uint32_t algonum = virtio_crypto_algs[i].algonum;
657 
658 		if (virtio_crypto_algs[i].active_devs == 0 ||
659 		    !virtcrypto_algo_is_supported(vcrypto, service, algonum))
660 			continue;
661 
662 		if (virtio_crypto_algs[i].active_devs == 1)
663 			crypto_unregister_skcipher(&virtio_crypto_algs[i].algo);
664 
665 		virtio_crypto_algs[i].active_devs--;
666 	}
667 
668 	mutex_unlock(&algs_lock);
669 }
670