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                 return -EINVAL;
 121         }
 122         return 0;
 123 }
 124
 125 static int virtio_crypto_alg_ablkcipher_init_session(
 126                 struct virtio_crypto_ablkcipher_ctx *ctx,
 127                 uint32_t alg, const uint8_t *key,
 128                 unsigned int keylen,
 129                 int encrypt)
 130 {
 131         struct scatterlist outhdr, key_sg, inhdr, *sgs[3];
 132         unsigned int tmp;
 133         struct virtio_crypto *vcrypto = ctx->vcrypto;
 134         int op = encrypt ? VIRTIO_CRYPTO_OP_ENCRYPT : VIRTIO_CRYPTO_OP_DECRYPT;
 135         int err;
 136         unsigned int num_out = 0, num_in = 0;
 137
 138         /*
 139          * Avoid to do DMA from the stack, switch to using
 140          * dynamically-allocated for the key
 141          */
 142         uint8_t *cipher_key = kmalloc(keylen, GFP_ATOMIC);
 143
 144         if (!cipher_key)
 145                 return -ENOMEM;
 146
 147         memcpy(cipher_key, key, keylen);
 148
 149         spin_lock(&vcrypto->ctrl_lock);
 150         /* Pad ctrl header */
 151         vcrypto->ctrl.header.opcode =
 152                 cpu_to_le32(VIRTIO_CRYPTO_CIPHER_CREATE_SESSION);
 153         vcrypto->ctrl.header.algo = cpu_to_le32(alg);
 154         /* Set the default dataqueue id to 0 */
 155         vcrypto->ctrl.header.queue_id = 0;
 156
 157         vcrypto->input.status = cpu_to_le32(VIRTIO_CRYPTO_ERR);
 158         /* Pad cipher's parameters */
 159         vcrypto->ctrl.u.sym_create_session.op_type =
 160                 cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
 161         vcrypto->ctrl.u.sym_create_session.u.cipher.para.algo =
 162                 vcrypto->ctrl.header.algo;
 163         vcrypto->ctrl.u.sym_create_session.u.cipher.para.keylen =
 164                 cpu_to_le32(keylen);
 165         vcrypto->ctrl.u.sym_create_session.u.cipher.para.op =
 166                 cpu_to_le32(op);
 167
 168         sg_init_one(&outhdr, &vcrypto->ctrl, sizeof(vcrypto->ctrl));
 169         sgs[num_out++] = &outhdr;
 170
 171         /* Set key */
 172         sg_init_one(&key_sg, cipher_key, keylen);
 173         sgs[num_out++] = &key_sg;
 174
 175         /* Return status and session id back */
 176         sg_init_one(&inhdr, &vcrypto->input, sizeof(vcrypto->input));
 177         sgs[num_out + num_in++] = &inhdr;
 178
 179         err = virtqueue_add_sgs(vcrypto->ctrl_vq, sgs, num_out,
 180                                 num_in, vcrypto, GFP_ATOMIC);
 181         if (err < 0) {
 182                 spin_unlock(&vcrypto->ctrl_lock);
 183                 kzfree(cipher_key);
 184                 return err;
 185         }
 186         virtqueue_kick(vcrypto->ctrl_vq);
 187
 188         /*
 189          * Trapping into the hypervisor, so the request should be
 190          * handled immediately.
 191          */
 192         while (!virtqueue_get_buf(vcrypto->ctrl_vq, &tmp) &&
 193                !virtqueue_is_broken(vcrypto->ctrl_vq))
 194                 cpu_relax();
 195
 196         if (le32_to_cpu(vcrypto->input.status) != VIRTIO_CRYPTO_OK) {
 197                 spin_unlock(&vcrypto->ctrl_lock);
 198                 pr_err("virtio_crypto: Create session failed status: %u\n",
 199                         le32_to_cpu(vcrypto->input.status));
 200                 kzfree(cipher_key);
 201                 return -EINVAL;
 202         }
 203
 204         if (encrypt)
 205                 ctx->enc_sess_info.session_id =
 206                         le64_to_cpu(vcrypto->input.session_id);
 207         else
 208                 ctx->dec_sess_info.session_id =
 209                         le64_to_cpu(vcrypto->input.session_id);
 210
 211         spin_unlock(&vcrypto->ctrl_lock);
 212
 213         kzfree(cipher_key);
 214         return 0;
 215 }
 216
 217 static int virtio_crypto_alg_ablkcipher_close_session(
 218                 struct virtio_crypto_ablkcipher_ctx *ctx,
 219                 int encrypt)
 220 {
 221         struct scatterlist outhdr, status_sg, *sgs[2];
 222         unsigned int tmp;
 223         struct virtio_crypto_destroy_session_req *destroy_session;
 224         struct virtio_crypto *vcrypto = ctx->vcrypto;
 225         int err;
 226         unsigned int num_out = 0, num_in = 0;
 227
 228         spin_lock(&vcrypto->ctrl_lock);
 229         vcrypto->ctrl_status.status = VIRTIO_CRYPTO_ERR;
 230         /* Pad ctrl header */
 231         vcrypto->ctrl.header.opcode =
 232                 cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DESTROY_SESSION);
 233         /* Set the default virtqueue id to 0 */
 234         vcrypto->ctrl.header.queue_id = 0;
 235
 236         destroy_session = &vcrypto->ctrl.u.destroy_session;
 237
 238         if (encrypt)
 239                 destroy_session->session_id =
 240                         cpu_to_le64(ctx->enc_sess_info.session_id);
 241         else
 242                 destroy_session->session_id =
 243                         cpu_to_le64(ctx->dec_sess_info.session_id);
 244
 245         sg_init_one(&outhdr, &vcrypto->ctrl, sizeof(vcrypto->ctrl));
 246         sgs[num_out++] = &outhdr;
 247
 248         /* Return status and session id back */
 249         sg_init_one(&status_sg, &vcrypto->ctrl_status.status,
 250                 sizeof(vcrypto->ctrl_status.status));
 251         sgs[num_out + num_in++] = &status_sg;
 252
 253         err = virtqueue_add_sgs(vcrypto->ctrl_vq, sgs, num_out,
 254                         num_in, vcrypto, GFP_ATOMIC);
 255         if (err < 0) {
 256                 spin_unlock(&vcrypto->ctrl_lock);
 257                 return err;
 258         }
 259         virtqueue_kick(vcrypto->ctrl_vq);
 260
 261         while (!virtqueue_get_buf(vcrypto->ctrl_vq, &tmp) &&
 262                !virtqueue_is_broken(vcrypto->ctrl_vq))
 263                 cpu_relax();
 264
 265         if (vcrypto->ctrl_status.status != VIRTIO_CRYPTO_OK) {
 266                 spin_unlock(&vcrypto->ctrl_lock);
 267                 pr_err("virtio_crypto: Close session failed status: %u, session_id: 0x%llx\n",
 268                         vcrypto->ctrl_status.status,
 269                         destroy_session->session_id);
 270
 271                 return -EINVAL;
 272         }
 273         spin_unlock(&vcrypto->ctrl_lock);
 274
 275         return 0;
 276 }
 277
 278 static int virtio_crypto_alg_ablkcipher_init_sessions(
 279                 struct virtio_crypto_ablkcipher_ctx *ctx,
 280                 const uint8_t *key, unsigned int keylen)
 281 {
 282         uint32_t alg;
 283         int ret;
 284         struct virtio_crypto *vcrypto = ctx->vcrypto;
 285
 286         if (keylen > vcrypto->max_cipher_key_len) {
 287                 pr_err("virtio_crypto: the key is too long\n");
 288                 goto bad_key;
 289         }
 290
 291         if (virtio_crypto_alg_validate_key(keylen, &alg))
 292                 goto bad_key;
 293
 294         /* Create encryption session */
 295         ret = virtio_crypto_alg_ablkcipher_init_session(ctx,
 296                         alg, key, keylen, 1);
 297         if (ret)
 298                 return ret;
 299         /* Create decryption session */
 300         ret = virtio_crypto_alg_ablkcipher_init_session(ctx,
 301                         alg, key, keylen, 0);
 302         if (ret) {
 303                 virtio_crypto_alg_ablkcipher_close_session(ctx, 1);
 304                 return ret;
 305         }
 306         return 0;
 307
 308 bad_key:
 309         crypto_tfm_set_flags(ctx->tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 310         return -EINVAL;
 311 }
 312
 313 /* Note: kernel crypto API realization */
 314 static int virtio_crypto_ablkcipher_setkey(struct crypto_ablkcipher *tfm,
 315                                          const uint8_t *key,
 316                                          unsigned int keylen)
 317 {
 318         struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(tfm);
 319         uint32_t alg;
 320         int ret;
 321
 322         ret = virtio_crypto_alg_validate_key(keylen, &alg);
 323         if (ret)
 324                 return ret;
 325
 326         if (!ctx->vcrypto) {
 327                 /* New key */
 328                 int node = virtio_crypto_get_current_node();
 329                 struct virtio_crypto *vcrypto =
 330                                       virtcrypto_get_dev_node(node,
 331                                       VIRTIO_CRYPTO_SERVICE_CIPHER, alg);
 332                 if (!vcrypto) {
 333                         pr_err("virtio_crypto: Could not find a virtio device in the system or unsupported algo\n");
 334                         return -ENODEV;
 335                 }
 336
 337                 ctx->vcrypto = vcrypto;
 338         } else {
 339                 /* Rekeying, we should close the created sessions previously */
 340                 virtio_crypto_alg_ablkcipher_close_session(ctx, 1);
 341                 virtio_crypto_alg_ablkcipher_close_session(ctx, 0);
 342         }
 343
 344         ret = virtio_crypto_alg_ablkcipher_init_sessions(ctx, key, keylen);
 345         if (ret) {
 346                 virtcrypto_dev_put(ctx->vcrypto);
 347                 ctx->vcrypto = NULL;
 348
 349                 return ret;
 350         }
 351
 352         return 0;
 353 }
 354
 355 static int
 356 __virtio_crypto_ablkcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
 357                 struct ablkcipher_request *req,
 358                 struct data_queue *data_vq)
 359 {
 360         struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
 361         struct virtio_crypto_ablkcipher_ctx *ctx = vc_sym_req->ablkcipher_ctx;
 362         struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 363         unsigned int ivsize = crypto_ablkcipher_ivsize(tfm);
 364         struct virtio_crypto *vcrypto = ctx->vcrypto;
 365         struct virtio_crypto_op_data_req *req_data;
 366         int src_nents, dst_nents;
 367         int err;
 368         unsigned long flags;
 369         struct scatterlist outhdr, iv_sg, status_sg, **sgs;
 370         u64 dst_len;
 371         unsigned int num_out = 0, num_in = 0;
 372         int sg_total;
 373         uint8_t *iv;
 374         struct scatterlist *sg;
 375
 376         src_nents = sg_nents_for_len(req->src, req->nbytes);
 377         if (src_nents < 0) {
 378                 pr_err("Invalid number of src SG.\n");
 379                 return src_nents;
 380         }
 381
 382         dst_nents = sg_nents(req->dst);
 383
 384         pr_debug("virtio_crypto: Number of sgs (src_nents: %d, dst_nents: %d)\n",
 385                         src_nents, dst_nents);
 386
 387         /* Why 3?  outhdr + iv + inhdr */
 388         sg_total = src_nents + dst_nents + 3;
 389         sgs = kcalloc_node(sg_total, sizeof(*sgs), GFP_KERNEL,
 390                                 dev_to_node(&vcrypto->vdev->dev));
 391         if (!sgs)
 392                 return -ENOMEM;
 393
 394         req_data = kzalloc_node(sizeof(*req_data), GFP_KERNEL,
 395                                 dev_to_node(&vcrypto->vdev->dev));
 396         if (!req_data) {
 397                 kfree(sgs);
 398                 return -ENOMEM;
 399         }
 400
 401         vc_req->req_data = req_data;
 402         vc_sym_req->type = VIRTIO_CRYPTO_SYM_OP_CIPHER;
 403         /* Head of operation */
 404         if (vc_sym_req->encrypt) {
 405                 req_data->header.session_id =
 406                         cpu_to_le64(ctx->enc_sess_info.session_id);
 407                 req_data->header.opcode =
 408                         cpu_to_le32(VIRTIO_CRYPTO_CIPHER_ENCRYPT);
 409         } else {
 410                 req_data->header.session_id =
 411                         cpu_to_le64(ctx->dec_sess_info.session_id);
 412             req_data->header.opcode =
 413                         cpu_to_le32(VIRTIO_CRYPTO_CIPHER_DECRYPT);
 414         }
 415         req_data->u.sym_req.op_type = cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
 416         req_data->u.sym_req.u.cipher.para.iv_len = cpu_to_le32(ivsize);
 417         req_data->u.sym_req.u.cipher.para.src_data_len =
 418                         cpu_to_le32(req->nbytes);
 419
 420         dst_len = virtio_crypto_alg_sg_nents_length(req->dst);
 421         if (unlikely(dst_len > U32_MAX)) {
 422                 pr_err("virtio_crypto: The dst_len is beyond U32_MAX\n");
 423                 err = -EINVAL;
 424                 goto free;
 425         }
 426
 427         dst_len = min_t(unsigned int, req->nbytes, dst_len);
 428         pr_debug("virtio_crypto: src_len: %u, dst_len: %llu\n",
 429                         req->nbytes, dst_len);
 430
 431         if (unlikely(req->nbytes + dst_len + ivsize +
 432                 sizeof(vc_req->status) > vcrypto->max_size)) {
 433                 pr_err("virtio_crypto: The length is too big\n");
 434                 err = -EINVAL;
 435                 goto free;
 436         }
 437
 438         req_data->u.sym_req.u.cipher.para.dst_data_len =
 439                         cpu_to_le32((uint32_t)dst_len);
 440
 441         /* Outhdr */
 442         sg_init_one(&outhdr, req_data, sizeof(*req_data));
 443         sgs[num_out++] = &outhdr;
 444
 445         /* IV */
 446
 447         /*
 448          * Avoid to do DMA from the stack, switch to using
 449          * dynamically-allocated for the IV
 450          */
 451         iv = kzalloc_node(ivsize, GFP_ATOMIC,
 452                                 dev_to_node(&vcrypto->vdev->dev));
 453         if (!iv) {
 454                 err = -ENOMEM;
 455                 goto free;
 456         }
 457         memcpy(iv, req->info, ivsize);
 458         if (!vc_sym_req->encrypt)
 459                 scatterwalk_map_and_copy(req->info, req->src,
 460                                          req->nbytes - AES_BLOCK_SIZE,
 461                                          AES_BLOCK_SIZE, 0);
 462
 463         sg_init_one(&iv_sg, iv, ivsize);
 464         sgs[num_out++] = &iv_sg;
 465         vc_sym_req->iv = iv;
 466
 467         /* Source data */
 468         for (sg = req->src; src_nents; sg = sg_next(sg), src_nents--)
 469                 sgs[num_out++] = sg;
 470
 471         /* Destination data */
 472         for (sg = req->dst; sg; sg = sg_next(sg))
 473                 sgs[num_out + num_in++] = sg;
 474
 475         /* Status */
 476         sg_init_one(&status_sg, &vc_req->status, sizeof(vc_req->status));
 477         sgs[num_out + num_in++] = &status_sg;
 478
 479         vc_req->sgs = sgs;
 480
 481         spin_lock_irqsave(&data_vq->lock, flags);
 482         err = virtqueue_add_sgs(data_vq->vq, sgs, num_out,
 483                                 num_in, vc_req, GFP_ATOMIC);
 484         virtqueue_kick(data_vq->vq);
 485         spin_unlock_irqrestore(&data_vq->lock, flags);
 486         if (unlikely(err < 0))
 487                 goto free_iv;
 488
 489         return 0;
 490
 491 free_iv:
 492         kzfree(iv);
 493 free:
 494         kzfree(req_data);
 495         kfree(sgs);
 496         return err;
 497 }
 498
 499 static int virtio_crypto_ablkcipher_encrypt(struct ablkcipher_request *req)
 500 {
 501         struct crypto_ablkcipher *atfm = crypto_ablkcipher_reqtfm(req);
 502         struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(atfm);
 503         struct virtio_crypto_sym_request *vc_sym_req =
 504                                 ablkcipher_request_ctx(req);
 505         struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 506         struct virtio_crypto *vcrypto = ctx->vcrypto;
 507         /* Use the first data virtqueue as default */
 508         struct data_queue *data_vq = &vcrypto->data_vq[0];
 509
 510         if (!req->nbytes)
 511                 return 0;
 512         if (req->nbytes % AES_BLOCK_SIZE)
 513                 return -EINVAL;
 514
 515         vc_req->dataq = data_vq;
 516         vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
 517         vc_sym_req->ablkcipher_ctx = ctx;
 518         vc_sym_req->ablkcipher_req = req;
 519         vc_sym_req->encrypt = true;
 520
 521         return crypto_transfer_ablkcipher_request_to_engine(data_vq->engine, req);
 522 }
 523
 524 static int virtio_crypto_ablkcipher_decrypt(struct ablkcipher_request *req)
 525 {
 526         struct crypto_ablkcipher *atfm = crypto_ablkcipher_reqtfm(req);
 527         struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(atfm);
 528         struct virtio_crypto_sym_request *vc_sym_req =
 529                                 ablkcipher_request_ctx(req);
 530         struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 531         struct virtio_crypto *vcrypto = ctx->vcrypto;
 532         /* Use the first data virtqueue as default */
 533         struct data_queue *data_vq = &vcrypto->data_vq[0];
 534
 535         if (!req->nbytes)
 536                 return 0;
 537         if (req->nbytes % AES_BLOCK_SIZE)
 538                 return -EINVAL;
 539
 540         vc_req->dataq = data_vq;
 541         vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
 542         vc_sym_req->ablkcipher_ctx = ctx;
 543         vc_sym_req->ablkcipher_req = req;
 544         vc_sym_req->encrypt = false;
 545
 546         return crypto_transfer_ablkcipher_request_to_engine(data_vq->engine, req);
 547 }
 548
 549 static int virtio_crypto_ablkcipher_init(struct crypto_tfm *tfm)
 550 {
 551         struct virtio_crypto_ablkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
 552
 553         tfm->crt_ablkcipher.reqsize = sizeof(struct virtio_crypto_sym_request);
 554         ctx->tfm = tfm;
 555
 556         ctx->enginectx.op.do_one_request = virtio_crypto_ablkcipher_crypt_req;
 557         ctx->enginectx.op.prepare_request = NULL;
 558         ctx->enginectx.op.unprepare_request = NULL;
 559         return 0;
 560 }
 561
 562 static void virtio_crypto_ablkcipher_exit(struct crypto_tfm *tfm)
 563 {
 564         struct virtio_crypto_ablkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
 565
 566         if (!ctx->vcrypto)
 567                 return;
 568
 569         virtio_crypto_alg_ablkcipher_close_session(ctx, 1);
 570         virtio_crypto_alg_ablkcipher_close_session(ctx, 0);
 571         virtcrypto_dev_put(ctx->vcrypto);
 572         ctx->vcrypto = NULL;
 573 }
 574
 575 int virtio_crypto_ablkcipher_crypt_req(
 576         struct crypto_engine *engine, void *vreq)
 577 {
 578         struct ablkcipher_request *req = container_of(vreq, struct ablkcipher_request, base);
 579         struct virtio_crypto_sym_request *vc_sym_req =
 580                                 ablkcipher_request_ctx(req);
 581         struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 582         struct data_queue *data_vq = vc_req->dataq;
 583         int ret;
 584
 585         ret = __virtio_crypto_ablkcipher_do_req(vc_sym_req, req, data_vq);
 586         if (ret < 0)
 587                 return ret;
 588
 589         virtqueue_kick(data_vq->vq);
 590
 591         return 0;
 592 }
 593
 594 static void virtio_crypto_ablkcipher_finalize_req(
 595         struct virtio_crypto_sym_request *vc_sym_req,
 596         struct ablkcipher_request *req,
 597         int err)
 598 {
 599         if (vc_sym_req->encrypt)
 600                 scatterwalk_map_and_copy(req->info, req->dst,
 601                                          req->nbytes - AES_BLOCK_SIZE,
 602                                          AES_BLOCK_SIZE, 0);
 603         kzfree(vc_sym_req->iv);
 604         virtcrypto_clear_request(&vc_sym_req->base);
 605
 606         crypto_finalize_ablkcipher_request(vc_sym_req->base.dataq->engine,
 607                                            req, err);
 608 }
 609
 610 static struct virtio_crypto_algo virtio_crypto_algs[] = { {
 611         .algonum = VIRTIO_CRYPTO_CIPHER_AES_CBC,
 612         .service = VIRTIO_CRYPTO_SERVICE_CIPHER,
 613         .algo = {
 614                 .cra_name = "cbc(aes)",
 615                 .cra_driver_name = "virtio_crypto_aes_cbc",
 616                 .cra_priority = 150,
 617                 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
 618                 .cra_blocksize = AES_BLOCK_SIZE,
 619                 .cra_ctxsize  = sizeof(struct virtio_crypto_ablkcipher_ctx),
 620                 .cra_alignmask = 0,
 621                 .cra_module = THIS_MODULE,
 622                 .cra_type = &crypto_ablkcipher_type,
 623                 .cra_init = virtio_crypto_ablkcipher_init,
 624                 .cra_exit = virtio_crypto_ablkcipher_exit,
 625                 .cra_u = {
 626                         .ablkcipher = {
 627                                 .setkey = virtio_crypto_ablkcipher_setkey,
 628                                 .decrypt = virtio_crypto_ablkcipher_decrypt,
 629                                 .encrypt = virtio_crypto_ablkcipher_encrypt,
 630                                 .min_keysize = AES_MIN_KEY_SIZE,
 631                                 .max_keysize = AES_MAX_KEY_SIZE,
 632                                 .ivsize = AES_BLOCK_SIZE,
 633                         },
 634                 },
 635         },
 636 } };
 637
 638 int virtio_crypto_algs_register(struct virtio_crypto *vcrypto)
 639 {
 640         int ret = 0;
 641         int i = 0;
 642
 643         mutex_lock(&algs_lock);
 644
 645         for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
 646
 647                 uint32_t service = virtio_crypto_algs[i].service;
 648                 uint32_t algonum = virtio_crypto_algs[i].algonum;
 649
 650                 if (!virtcrypto_algo_is_supported(vcrypto, service, algonum))
 651                         continue;
 652
 653                 if (virtio_crypto_algs[i].active_devs == 0) {
 654                         ret = crypto_register_alg(&virtio_crypto_algs[i].algo);
 655                         if (ret)
 656                                 goto unlock;
 657                 }
 658
 659                 virtio_crypto_algs[i].active_devs++;
 660                 dev_info(&vcrypto->vdev->dev, "Registered algo %s\n",
 661                          virtio_crypto_algs[i].algo.cra_name);
 662         }
 663
 664 unlock:
 665         mutex_unlock(&algs_lock);
 666         return ret;
 667 }
 668
 669 void virtio_crypto_algs_unregister(struct virtio_crypto *vcrypto)
 670 {
 671         int i = 0;
 672
 673         mutex_lock(&algs_lock);
 674
 675         for (i = 0; i < ARRAY_SIZE(virtio_crypto_algs); i++) {
 676
 677                 uint32_t service = virtio_crypto_algs[i].service;
 678                 uint32_t algonum = virtio_crypto_algs[i].algonum;
 679
 680                 if (virtio_crypto_algs[i].active_devs == 0 ||
 681                     !virtcrypto_algo_is_supported(vcrypto, service, algonum))
 682                         continue;
 683
 684                 if (virtio_crypto_algs[i].active_devs == 1)
 685                         crypto_unregister_alg(&virtio_crypto_algs[i].algo);
 686
 687                 virtio_crypto_algs[i].active_devs--;
 688         }
 689
 690         mutex_unlock(&algs_lock);
 691 }