drivers/crypto/virtio/virtio_crypto_algs.c

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