drivers/crypto/virtio/virtio_crypto_skcipher_algs.c

   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
  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
  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
 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
 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         struct virtio_crypto *vcrypto = ctx->vcrypto;
 122         int op = encrypt ? VIRTIO_CRYPTO_OP_ENCRYPT : VIRTIO_CRYPTO_OP_DECRYPT;
 123         int err;
 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;
 129
 130         /*
 131          * Avoid to do DMA from the stack, switch to using
 132          * dynamically-allocated for the key
 133          */
 134         uint8_t *cipher_key = kmemdup(key, keylen, GFP_ATOMIC);
 135
 136         if (!cipher_key)
 137                 return -ENOMEM;
 138
 139         vc_ctrl_req = kzalloc(sizeof(*vc_ctrl_req), GFP_KERNEL);
 140         if (!vc_ctrl_req) {
 141                 err = -ENOMEM;
 142                 goto out;
 143         }
 144
 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;
 151
 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);
 160
 161         sg_init_one(&outhdr, ctrl, sizeof(*ctrl));
 162         sgs[num_out++] = &outhdr;
 163
 164         /* Set key */
 165         sg_init_one(&key_sg, cipher_key, keylen);
 166         sgs[num_out++] = &key_sg;
 167
 168         /* Return status and session id back */
 169         sg_init_one(&inhdr, input, sizeof(*input));
 170         sgs[num_out + num_in++] = &inhdr;
 171
 172         err = virtio_crypto_ctrl_vq_request(vcrypto, sgs, num_out, num_in, vc_ctrl_req);
 173         if (err < 0)
 174                 goto out;
 175
 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));
 179                 err = -EINVAL;
 180                 goto out;
 181         }
 182
 183         if (encrypt)
 184                 ctx->enc_sess_info.session_id = le64_to_cpu(input->session_id);
 185         else
 186                 ctx->dec_sess_info.session_id = le64_to_cpu(input->session_id);
 187
 188         err = 0;
 189 out:
 190         kfree(vc_ctrl_req);
 191         kfree_sensitive(cipher_key);
 192         return err;
 193 }
 194
 195 static int virtio_crypto_alg_skcipher_close_session(
 196                 struct virtio_crypto_skcipher_ctx *ctx,
 197                 int encrypt)
 198 {
 199         struct scatterlist outhdr, status_sg, *sgs[2];
 200         struct virtio_crypto_destroy_session_req *destroy_session;
 201         struct virtio_crypto *vcrypto = ctx->vcrypto;
 202         int err;
 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;
 207
 208         vc_ctrl_req = kzalloc(sizeof(*vc_ctrl_req), GFP_KERNEL);
 209         if (!vc_ctrl_req)
 210                 return -ENOMEM;
 211
 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;
 219
 220         destroy_session = &ctrl->u.destroy_session;
 221
 222         if (encrypt)
 223                 destroy_session->session_id = cpu_to_le64(ctx->enc_sess_info.session_id);
 224         else
 225                 destroy_session->session_id = cpu_to_le64(ctx->dec_sess_info.session_id);
 226
 227         sg_init_one(&outhdr, ctrl, sizeof(*ctrl));
 228         sgs[num_out++] = &outhdr;
 229
 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;
 233
 234         err = virtio_crypto_ctrl_vq_request(vcrypto, sgs, num_out, num_in, vc_ctrl_req);
 235         if (err < 0)
 236                 goto out;
 237
 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);
 241
 242                 err = -EINVAL;
 243                 goto out;
 244         }
 245
 246         err = 0;
 247 out:
 248         kfree(vc_ctrl_req);
 249         return err;
 250 }
 251
 252 static int virtio_crypto_alg_skcipher_init_sessions(
 253                 struct virtio_crypto_skcipher_ctx *ctx,
 254                 const uint8_t *key, unsigned int keylen)
 255 {
 256         uint32_t alg;
 257         int ret;
 258         struct virtio_crypto *vcrypto = ctx->vcrypto;
 259
 260         if (keylen > vcrypto->max_cipher_key_len) {
 261                 pr_err("virtio_crypto: the key is too long\n");
 262                 return -EINVAL;
 263         }
 264
 265         if (virtio_crypto_alg_validate_key(keylen, &alg))
 266                 return -EINVAL;
 267
 268         /* Create encryption session */
 269         ret = virtio_crypto_alg_skcipher_init_session(ctx,
 270                         alg, key, keylen, 1);
 271         if (ret)
 272                 return ret;
 273         /* Create decryption session */
 274         ret = virtio_crypto_alg_skcipher_init_session(ctx,
 275                         alg, key, keylen, 0);
 276         if (ret) {
 277                 virtio_crypto_alg_skcipher_close_session(ctx, 1);
 278                 return ret;
 279         }
 280         return 0;
 281 }
 282
 283 /* Note: kernel crypto API realization */
 284 static int virtio_crypto_skcipher_setkey(struct crypto_skcipher *tfm,
 285                                          const uint8_t *key,
 286                                          unsigned int keylen)
 287 {
 288         struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 289         uint32_t alg;
 290         int ret;
 291
 292         ret = virtio_crypto_alg_validate_key(keylen, &alg);
 293         if (ret)
 294                 return ret;
 295
 296         if (!ctx->vcrypto) {
 297                 /* New key */
 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);
 302                 if (!vcrypto) {
 303                         pr_err("virtio_crypto: Could not find a virtio device in the system or unsupported algo\n");
 304                         return -ENODEV;
 305                 }
 306
 307                 ctx->vcrypto = vcrypto;
 308         } else {
 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);
 312         }
 313
 314         ret = virtio_crypto_alg_skcipher_init_sessions(ctx, key, keylen);
 315         if (ret) {
 316                 virtcrypto_dev_put(ctx->vcrypto);
 317                 ctx->vcrypto = NULL;
 318
 319                 return ret;
 320         }
 321
 322         return 0;
 323 }
 324
 325 static int
 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)
 329 {
 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;
 337         int err;
 338         unsigned long flags;
 339         struct scatterlist outhdr, iv_sg, status_sg, **sgs;
 340         u64 dst_len;
 341         unsigned int num_out = 0, num_in = 0;
 342         int sg_total;
 343         uint8_t *iv;
 344         struct scatterlist *sg;
 345
 346         src_nents = sg_nents_for_len(req->src, req->cryptlen);
 347         if (src_nents < 0) {
 348                 pr_err("Invalid number of src SG.\n");
 349                 return src_nents;
 350         }
 351
 352         dst_nents = sg_nents(req->dst);
 353
 354         pr_debug("virtio_crypto: Number of sgs (src_nents: %d, dst_nents: %d)\n",
 355                         src_nents, dst_nents);
 356
 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));
 361         if (!sgs)
 362                 return -ENOMEM;
 363
 364         req_data = kzalloc_node(sizeof(*req_data), GFP_KERNEL,
 365                                 dev_to_node(&vcrypto->vdev->dev));
 366         if (!req_data) {
 367                 kfree(sgs);
 368                 return -ENOMEM;
 369         }
 370
 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);
 379         } else {
 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);
 384         }
 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);
 389
 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");
 393                 err = -EINVAL;
 394                 goto free;
 395         }
 396
 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);
 400
 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");
 404                 err = -EINVAL;
 405                 goto free;
 406         }
 407
 408         req_data->u.sym_req.u.cipher.para.dst_data_len =
 409                         cpu_to_le32((uint32_t)dst_len);
 410
 411         /* Outhdr */
 412         sg_init_one(&outhdr, req_data, sizeof(*req_data));
 413         sgs[num_out++] = &outhdr;
 414
 415         /* IV */
 416
 417         /*
 418          * Avoid to do DMA from the stack, switch to using
 419          * dynamically-allocated for the IV
 420          */
 421         iv = kzalloc_node(ivsize, GFP_ATOMIC,
 422                                 dev_to_node(&vcrypto->vdev->dev));
 423         if (!iv) {
 424                 err = -ENOMEM;
 425                 goto free;
 426         }
 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,
 431                                          AES_BLOCK_SIZE, 0);
 432
 433         sg_init_one(&iv_sg, iv, ivsize);
 434         sgs[num_out++] = &iv_sg;
 435         vc_sym_req->iv = iv;
 436
 437         /* Source data */
 438         for (sg = req->src; src_nents; sg = sg_next(sg), src_nents--)
 439                 sgs[num_out++] = sg;
 440
 441         /* Destination data */
 442         for (sg = req->dst; sg; sg = sg_next(sg))
 443                 sgs[num_out + num_in++] = sg;
 444
 445         /* Status */
 446         sg_init_one(&status_sg, &vc_req->status, sizeof(vc_req->status));
 447         sgs[num_out + num_in++] = &status_sg;
 448
 449         vc_req->sgs = sgs;
 450
 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))
 457                 goto free_iv;
 458
 459         return 0;
 460
 461 free_iv:
 462         kfree_sensitive(iv);
 463 free:
 464         kfree_sensitive(req_data);
 465         kfree(sgs);
 466         return err;
 467 }
 468
 469 static int virtio_crypto_skcipher_encrypt(struct skcipher_request *req)
 470 {
 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];
 479
 480         if (!req->cryptlen)
 481                 return 0;
 482         if (req->cryptlen % AES_BLOCK_SIZE)
 483                 return -EINVAL;
 484
 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;
 490
 491         return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
 492 }
 493
 494 static int virtio_crypto_skcipher_decrypt(struct skcipher_request *req)
 495 {
 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];
 504
 505         if (!req->cryptlen)
 506                 return 0;
 507         if (req->cryptlen % AES_BLOCK_SIZE)
 508                 return -EINVAL;
 509
 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;
 515
 516         return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
 517 }
 518
 519 static int virtio_crypto_skcipher_init(struct crypto_skcipher *tfm)
 520 {
 521         struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 522
 523         crypto_skcipher_set_reqsize(tfm, sizeof(struct virtio_crypto_sym_request));
 524         ctx->tfm = tfm;
 525
 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;
 529         return 0;
 530 }
 531
 532 static void virtio_crypto_skcipher_exit(struct crypto_skcipher *tfm)
 533 {
 534         struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 535
 536         if (!ctx->vcrypto)
 537                 return;
 538
 539         virtio_crypto_alg_skcipher_close_session(ctx, 1);
 540         virtio_crypto_alg_skcipher_close_session(ctx, 0);
 541         virtcrypto_dev_put(ctx->vcrypto);
 542         ctx->vcrypto = NULL;
 543 }
 544
 545 int virtio_crypto_skcipher_crypt_req(
 546         struct crypto_engine *engine, void *vreq)
 547 {
 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;
 553         int ret;
 554
 555         ret = __virtio_crypto_skcipher_do_req(vc_sym_req, req, data_vq);
 556         if (ret < 0)
 557                 return ret;
 558
 559         virtqueue_kick(data_vq->vq);
 560
 561         return 0;
 562 }
 563
 564 static void virtio_crypto_skcipher_finalize_req(
 565         struct virtio_crypto_sym_request *vc_sym_req,
 566         struct skcipher_request *req,
 567         int err)
 568 {
 569         if (vc_sym_req->encrypt)
 570                 scatterwalk_map_and_copy(req->iv, req->dst,
 571                                          req->cryptlen - AES_BLOCK_SIZE,
 572                                          AES_BLOCK_SIZE, 0);
 573         kfree_sensitive(vc_sym_req->iv);
 574         virtcrypto_clear_request(&vc_sym_req->base);
 575
 576         crypto_finalize_skcipher_request(vc_sym_req->base.dataq->engine,
 577                                            req, err);
 578 }
 579
 580 static struct virtio_crypto_algo virtio_crypto_algs[] = { {
 581         .algonum = VIRTIO_CRYPTO_CIPHER_AES_CBC,
 582         .service = VIRTIO_CRYPTO_SERVICE_CIPHER,
 583         .algo = {
 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,
 600         },
 601 } };
 602
 603 int virtio_crypto_skcipher_algs_register(struct virtio_crypto *vcrypto)
 604 {
 605         int ret = 0;
 606         int i = 0;
 607
 608         mutex_lock(&algs_lock);
 609
 610         for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
 611
 612                 uint32_t service = virtio_crypto_algs[i].service;
 613                 uint32_t algonum = virtio_crypto_algs[i].algonum;
 614
 615                 if (!virtcrypto_algo_is_supported(vcrypto, service, algonum))
 616                         continue;
 617
 618                 if (virtio_crypto_algs[i].active_devs == 0) {
 619                         ret = crypto_register_skcipher(&virtio_crypto_algs[i].algo);
 620                         if (ret)
 621                                 goto unlock;
 622                 }
 623
 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);
 627         }
 628
 629 unlock:
 630         mutex_unlock(&algs_lock);
 631         return ret;
 632 }
 633
 634 void virtio_crypto_skcipher_algs_unregister(struct virtio_crypto *vcrypto)
 635 {
 636         int i = 0;
 637
 638         mutex_lock(&algs_lock);
 639
 640         for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
 641
 642                 uint32_t service = virtio_crypto_algs[i].service;
 643                 uint32_t algonum = virtio_crypto_algs[i].algonum;
 644
 645                 if (virtio_crypto_algs[i].active_devs == 0 ||
 646                     !virtcrypto_algo_is_supported(vcrypto, service, algonum))
 647                         continue;
 648
 649                 if (virtio_crypto_algs[i].active_devs == 1)
 650                         crypto_unregister_skcipher(&virtio_crypto_algs[i].algo);
 651
 652                 virtio_crypto_algs[i].active_devs--;
 653         }
 654
 655         mutex_unlock(&algs_lock);
 656 }