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