1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Algorithms supported by virtio crypto device
4 * Authors: Gonglei <arei.gonglei@huawei.com>
6 * Copyright 2016 HUAWEI TECHNOLOGIES CO., LTD.
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>
16 #include <uapi/linux/virtio_crypto.h>
17 #include "virtio_crypto_common.h"
20 struct virtio_crypto_skcipher_ctx {
21 struct crypto_engine_ctx enginectx;
22 struct virtio_crypto *vcrypto;
23 struct crypto_skcipher *tfm;
25 struct virtio_crypto_sym_session_info enc_sess_info;
26 struct virtio_crypto_sym_session_info dec_sess_info;
29 struct virtio_crypto_sym_request {
30 struct virtio_crypto_request base;
34 struct virtio_crypto_skcipher_ctx *skcipher_ctx;
35 struct skcipher_request *skcipher_req;
41 struct virtio_crypto_algo {
44 unsigned int active_devs;
45 struct skcipher_alg algo;
49 * The algs_lock protects the below global virtio_crypto_active_devs
50 * and crypto algorithms registion.
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,
58 static void virtio_crypto_dataq_sym_callback
59 (struct virtio_crypto_request *vc_req, int len)
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;
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:
72 case VIRTIO_CRYPTO_INVSESS:
73 case VIRTIO_CRYPTO_ERR:
76 case VIRTIO_CRYPTO_BADMSG:
83 ablk_req = vc_sym_req->skcipher_req;
84 virtio_crypto_skcipher_finalize_req(vc_sym_req,
89 static u64 virtio_crypto_alg_sg_nents_length(struct scatterlist *sg)
93 for (total = 0; sg; sg = sg_next(sg))
100 virtio_crypto_alg_validate_key(int key_len, uint32_t *alg)
103 case AES_KEYSIZE_128:
104 case AES_KEYSIZE_192:
105 case AES_KEYSIZE_256:
106 *alg = VIRTIO_CRYPTO_CIPHER_AES_CBC;
114 static int virtio_crypto_alg_skcipher_init_session(
115 struct virtio_crypto_skcipher_ctx *ctx,
116 uint32_t alg, const uint8_t *key,
120 struct scatterlist outhdr, key_sg, inhdr, *sgs[3];
121 struct virtio_crypto *vcrypto = ctx->vcrypto;
122 int op = encrypt ? VIRTIO_CRYPTO_OP_ENCRYPT : VIRTIO_CRYPTO_OP_DECRYPT;
124 unsigned int num_out = 0, num_in = 0;
125 struct virtio_crypto_op_ctrl_req *ctrl;
126 struct virtio_crypto_session_input *input;
127 struct virtio_crypto_sym_create_session_req *sym_create_session;
128 struct virtio_crypto_ctrl_request *vc_ctrl_req;
131 * Avoid to do DMA from the stack, switch to using
132 * dynamically-allocated for the key
134 uint8_t *cipher_key = kmemdup(key, keylen, GFP_ATOMIC);
139 vc_ctrl_req = kzalloc(sizeof(*vc_ctrl_req), GFP_KERNEL);
145 /* Pad ctrl header */
146 ctrl = &vc_ctrl_req->ctrl;
147 ctrl->header.opcode = cpu_to_le32(VIRTIO_CRYPTO_CIPHER_CREATE_SESSION);
148 ctrl->header.algo = cpu_to_le32(alg);
149 /* Set the default dataqueue id to 0 */
150 ctrl->header.queue_id = 0;
152 input = &vc_ctrl_req->input;
153 input->status = cpu_to_le32(VIRTIO_CRYPTO_ERR);
154 /* Pad cipher's parameters */
155 sym_create_session = &ctrl->u.sym_create_session;
156 sym_create_session->op_type = cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
157 sym_create_session->u.cipher.para.algo = ctrl->header.algo;
158 sym_create_session->u.cipher.para.keylen = cpu_to_le32(keylen);
159 sym_create_session->u.cipher.para.op = cpu_to_le32(op);
161 sg_init_one(&outhdr, ctrl, sizeof(*ctrl));
162 sgs[num_out++] = &outhdr;
165 sg_init_one(&key_sg, cipher_key, keylen);
166 sgs[num_out++] = &key_sg;
168 /* Return status and session id back */
169 sg_init_one(&inhdr, input, sizeof(*input));
170 sgs[num_out + num_in++] = &inhdr;
172 err = virtio_crypto_ctrl_vq_request(vcrypto, sgs, num_out, num_in, vc_ctrl_req);
176 if (le32_to_cpu(input->status) != VIRTIO_CRYPTO_OK) {
177 pr_err("virtio_crypto: Create session failed status: %u\n",
178 le32_to_cpu(input->status));
184 ctx->enc_sess_info.session_id = le64_to_cpu(input->session_id);
186 ctx->dec_sess_info.session_id = le64_to_cpu(input->session_id);
191 kfree_sensitive(cipher_key);
195 static int virtio_crypto_alg_skcipher_close_session(
196 struct virtio_crypto_skcipher_ctx *ctx,
199 struct scatterlist outhdr, status_sg, *sgs[2];
200 struct virtio_crypto_destroy_session_req *destroy_session;
201 struct virtio_crypto *vcrypto = ctx->vcrypto;
203 unsigned int num_out = 0, num_in = 0;
204 struct virtio_crypto_op_ctrl_req *ctrl;
205 struct virtio_crypto_inhdr *ctrl_status;
206 struct virtio_crypto_ctrl_request *vc_ctrl_req;
208 vc_ctrl_req = kzalloc(sizeof(*vc_ctrl_req), GFP_KERNEL);
212 ctrl_status = &vc_ctrl_req->ctrl_status;
213 ctrl_status->status = VIRTIO_CRYPTO_ERR;
214 /* Pad ctrl header */
215 ctrl = &vc_ctrl_req->ctrl;
216 ctrl->header.opcode = cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DESTROY_SESSION);
217 /* Set the default virtqueue id to 0 */
218 ctrl->header.queue_id = 0;
220 destroy_session = &ctrl->u.destroy_session;
223 destroy_session->session_id = cpu_to_le64(ctx->enc_sess_info.session_id);
225 destroy_session->session_id = cpu_to_le64(ctx->dec_sess_info.session_id);
227 sg_init_one(&outhdr, ctrl, sizeof(*ctrl));
228 sgs[num_out++] = &outhdr;
230 /* Return status and session id back */
231 sg_init_one(&status_sg, &ctrl_status->status, sizeof(ctrl_status->status));
232 sgs[num_out + num_in++] = &status_sg;
234 err = virtio_crypto_ctrl_vq_request(vcrypto, sgs, num_out, num_in, vc_ctrl_req);
238 if (ctrl_status->status != VIRTIO_CRYPTO_OK) {
239 pr_err("virtio_crypto: Close session failed status: %u, session_id: 0x%llx\n",
240 ctrl_status->status, destroy_session->session_id);
252 static int virtio_crypto_alg_skcipher_init_sessions(
253 struct virtio_crypto_skcipher_ctx *ctx,
254 const uint8_t *key, unsigned int keylen)
258 struct virtio_crypto *vcrypto = ctx->vcrypto;
260 if (keylen > vcrypto->max_cipher_key_len) {
261 pr_err("virtio_crypto: the key is too long\n");
265 if (virtio_crypto_alg_validate_key(keylen, &alg))
268 /* Create encryption session */
269 ret = virtio_crypto_alg_skcipher_init_session(ctx,
270 alg, key, keylen, 1);
273 /* Create decryption session */
274 ret = virtio_crypto_alg_skcipher_init_session(ctx,
275 alg, key, keylen, 0);
277 virtio_crypto_alg_skcipher_close_session(ctx, 1);
283 /* Note: kernel crypto API realization */
284 static int virtio_crypto_skcipher_setkey(struct crypto_skcipher *tfm,
288 struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
292 ret = virtio_crypto_alg_validate_key(keylen, &alg);
298 int node = virtio_crypto_get_current_node();
299 struct virtio_crypto *vcrypto =
300 virtcrypto_get_dev_node(node,
301 VIRTIO_CRYPTO_SERVICE_CIPHER, alg);
303 pr_err("virtio_crypto: Could not find a virtio device in the system or unsupported algo\n");
307 ctx->vcrypto = vcrypto;
309 /* Rekeying, we should close the created sessions previously */
310 virtio_crypto_alg_skcipher_close_session(ctx, 1);
311 virtio_crypto_alg_skcipher_close_session(ctx, 0);
314 ret = virtio_crypto_alg_skcipher_init_sessions(ctx, key, keylen);
316 virtcrypto_dev_put(ctx->vcrypto);
326 __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
327 struct skcipher_request *req,
328 struct data_queue *data_vq)
330 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
331 struct virtio_crypto_skcipher_ctx *ctx = vc_sym_req->skcipher_ctx;
332 struct virtio_crypto_request *vc_req = &vc_sym_req->base;
333 unsigned int ivsize = crypto_skcipher_ivsize(tfm);
334 struct virtio_crypto *vcrypto = ctx->vcrypto;
335 struct virtio_crypto_op_data_req *req_data;
336 int src_nents, dst_nents;
339 struct scatterlist outhdr, iv_sg, status_sg, **sgs;
341 unsigned int num_out = 0, num_in = 0;
344 struct scatterlist *sg;
346 src_nents = sg_nents_for_len(req->src, req->cryptlen);
348 pr_err("Invalid number of src SG.\n");
352 dst_nents = sg_nents(req->dst);
354 pr_debug("virtio_crypto: Number of sgs (src_nents: %d, dst_nents: %d)\n",
355 src_nents, dst_nents);
357 /* Why 3? outhdr + iv + inhdr */
358 sg_total = src_nents + dst_nents + 3;
359 sgs = kcalloc_node(sg_total, sizeof(*sgs), GFP_KERNEL,
360 dev_to_node(&vcrypto->vdev->dev));
364 req_data = kzalloc_node(sizeof(*req_data), GFP_KERNEL,
365 dev_to_node(&vcrypto->vdev->dev));
371 vc_req->req_data = req_data;
372 vc_sym_req->type = VIRTIO_CRYPTO_SYM_OP_CIPHER;
373 /* Head of operation */
374 if (vc_sym_req->encrypt) {
375 req_data->header.session_id =
376 cpu_to_le64(ctx->enc_sess_info.session_id);
377 req_data->header.opcode =
378 cpu_to_le32(VIRTIO_CRYPTO_CIPHER_ENCRYPT);
380 req_data->header.session_id =
381 cpu_to_le64(ctx->dec_sess_info.session_id);
382 req_data->header.opcode =
383 cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DECRYPT);
385 req_data->u.sym_req.op_type = cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
386 req_data->u.sym_req.u.cipher.para.iv_len = cpu_to_le32(ivsize);
387 req_data->u.sym_req.u.cipher.para.src_data_len =
388 cpu_to_le32(req->cryptlen);
390 dst_len = virtio_crypto_alg_sg_nents_length(req->dst);
391 if (unlikely(dst_len > U32_MAX)) {
392 pr_err("virtio_crypto: The dst_len is beyond U32_MAX\n");
397 dst_len = min_t(unsigned int, req->cryptlen, dst_len);
398 pr_debug("virtio_crypto: src_len: %u, dst_len: %llu\n",
399 req->cryptlen, dst_len);
401 if (unlikely(req->cryptlen + dst_len + ivsize +
402 sizeof(vc_req->status) > vcrypto->max_size)) {
403 pr_err("virtio_crypto: The length is too big\n");
408 req_data->u.sym_req.u.cipher.para.dst_data_len =
409 cpu_to_le32((uint32_t)dst_len);
412 sg_init_one(&outhdr, req_data, sizeof(*req_data));
413 sgs[num_out++] = &outhdr;
418 * Avoid to do DMA from the stack, switch to using
419 * dynamically-allocated for the IV
421 iv = kzalloc_node(ivsize, GFP_ATOMIC,
422 dev_to_node(&vcrypto->vdev->dev));
427 memcpy(iv, req->iv, ivsize);
428 if (!vc_sym_req->encrypt)
429 scatterwalk_map_and_copy(req->iv, req->src,
430 req->cryptlen - AES_BLOCK_SIZE,
433 sg_init_one(&iv_sg, iv, ivsize);
434 sgs[num_out++] = &iv_sg;
438 for (sg = req->src; src_nents; sg = sg_next(sg), src_nents--)
441 /* Destination data */
442 for (sg = req->dst; sg; sg = sg_next(sg))
443 sgs[num_out + num_in++] = sg;
446 sg_init_one(&status_sg, &vc_req->status, sizeof(vc_req->status));
447 sgs[num_out + num_in++] = &status_sg;
451 spin_lock_irqsave(&data_vq->lock, flags);
452 err = virtqueue_add_sgs(data_vq->vq, sgs, num_out,
453 num_in, vc_req, GFP_ATOMIC);
454 virtqueue_kick(data_vq->vq);
455 spin_unlock_irqrestore(&data_vq->lock, flags);
456 if (unlikely(err < 0))
464 kfree_sensitive(req_data);
469 static int virtio_crypto_skcipher_encrypt(struct skcipher_request *req)
471 struct crypto_skcipher *atfm = crypto_skcipher_reqtfm(req);
472 struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(atfm);
473 struct virtio_crypto_sym_request *vc_sym_req =
474 skcipher_request_ctx(req);
475 struct virtio_crypto_request *vc_req = &vc_sym_req->base;
476 struct virtio_crypto *vcrypto = ctx->vcrypto;
477 /* Use the first data virtqueue as default */
478 struct data_queue *data_vq = &vcrypto->data_vq[0];
482 if (req->cryptlen % AES_BLOCK_SIZE)
485 vc_req->dataq = data_vq;
486 vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
487 vc_sym_req->skcipher_ctx = ctx;
488 vc_sym_req->skcipher_req = req;
489 vc_sym_req->encrypt = true;
491 return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
494 static int virtio_crypto_skcipher_decrypt(struct skcipher_request *req)
496 struct crypto_skcipher *atfm = crypto_skcipher_reqtfm(req);
497 struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(atfm);
498 struct virtio_crypto_sym_request *vc_sym_req =
499 skcipher_request_ctx(req);
500 struct virtio_crypto_request *vc_req = &vc_sym_req->base;
501 struct virtio_crypto *vcrypto = ctx->vcrypto;
502 /* Use the first data virtqueue as default */
503 struct data_queue *data_vq = &vcrypto->data_vq[0];
507 if (req->cryptlen % AES_BLOCK_SIZE)
510 vc_req->dataq = data_vq;
511 vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
512 vc_sym_req->skcipher_ctx = ctx;
513 vc_sym_req->skcipher_req = req;
514 vc_sym_req->encrypt = false;
516 return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
519 static int virtio_crypto_skcipher_init(struct crypto_skcipher *tfm)
521 struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
523 crypto_skcipher_set_reqsize(tfm, sizeof(struct virtio_crypto_sym_request));
526 ctx->enginectx.op.do_one_request = virtio_crypto_skcipher_crypt_req;
527 ctx->enginectx.op.prepare_request = NULL;
528 ctx->enginectx.op.unprepare_request = NULL;
532 static void virtio_crypto_skcipher_exit(struct crypto_skcipher *tfm)
534 struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
539 virtio_crypto_alg_skcipher_close_session(ctx, 1);
540 virtio_crypto_alg_skcipher_close_session(ctx, 0);
541 virtcrypto_dev_put(ctx->vcrypto);
545 int virtio_crypto_skcipher_crypt_req(
546 struct crypto_engine *engine, void *vreq)
548 struct skcipher_request *req = container_of(vreq, struct skcipher_request, base);
549 struct virtio_crypto_sym_request *vc_sym_req =
550 skcipher_request_ctx(req);
551 struct virtio_crypto_request *vc_req = &vc_sym_req->base;
552 struct data_queue *data_vq = vc_req->dataq;
555 ret = __virtio_crypto_skcipher_do_req(vc_sym_req, req, data_vq);
559 virtqueue_kick(data_vq->vq);
564 static void virtio_crypto_skcipher_finalize_req(
565 struct virtio_crypto_sym_request *vc_sym_req,
566 struct skcipher_request *req,
569 if (vc_sym_req->encrypt)
570 scatterwalk_map_and_copy(req->iv, req->dst,
571 req->cryptlen - AES_BLOCK_SIZE,
573 kfree_sensitive(vc_sym_req->iv);
574 virtcrypto_clear_request(&vc_sym_req->base);
576 crypto_finalize_skcipher_request(vc_sym_req->base.dataq->engine,
580 static struct virtio_crypto_algo virtio_crypto_algs[] = { {
581 .algonum = VIRTIO_CRYPTO_CIPHER_AES_CBC,
582 .service = VIRTIO_CRYPTO_SERVICE_CIPHER,
584 .base.cra_name = "cbc(aes)",
585 .base.cra_driver_name = "virtio_crypto_aes_cbc",
586 .base.cra_priority = 150,
587 .base.cra_flags = CRYPTO_ALG_ASYNC |
588 CRYPTO_ALG_ALLOCATES_MEMORY,
589 .base.cra_blocksize = AES_BLOCK_SIZE,
590 .base.cra_ctxsize = sizeof(struct virtio_crypto_skcipher_ctx),
591 .base.cra_module = THIS_MODULE,
592 .init = virtio_crypto_skcipher_init,
593 .exit = virtio_crypto_skcipher_exit,
594 .setkey = virtio_crypto_skcipher_setkey,
595 .decrypt = virtio_crypto_skcipher_decrypt,
596 .encrypt = virtio_crypto_skcipher_encrypt,
597 .min_keysize = AES_MIN_KEY_SIZE,
598 .max_keysize = AES_MAX_KEY_SIZE,
599 .ivsize = AES_BLOCK_SIZE,
603 int virtio_crypto_algs_register(struct virtio_crypto *vcrypto)
608 mutex_lock(&algs_lock);
610 for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
612 uint32_t service = virtio_crypto_algs[i].service;
613 uint32_t algonum = virtio_crypto_algs[i].algonum;
615 if (!virtcrypto_algo_is_supported(vcrypto, service, algonum))
618 if (virtio_crypto_algs[i].active_devs == 0) {
619 ret = crypto_register_skcipher(&virtio_crypto_algs[i].algo);
624 virtio_crypto_algs[i].active_devs++;
625 dev_info(&vcrypto->vdev->dev, "Registered algo %s\n",
626 virtio_crypto_algs[i].algo.base.cra_name);
630 mutex_unlock(&algs_lock);
634 void virtio_crypto_algs_unregister(struct virtio_crypto *vcrypto)
638 mutex_lock(&algs_lock);
640 for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
642 uint32_t service = virtio_crypto_algs[i].service;
643 uint32_t algonum = virtio_crypto_algs[i].algonum;
645 if (virtio_crypto_algs[i].active_devs == 0 ||
646 !virtcrypto_algo_is_supported(vcrypto, service, algonum))
649 if (virtio_crypto_algs[i].active_devs == 1)
650 crypto_unregister_skcipher(&virtio_crypto_algs[i].algo);
652 virtio_crypto_algs[i].active_devs--;
655 mutex_unlock(&algs_lock);