linux/drivers/crypto/qce/skcipher.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2010-2014, The Linux Foundation. All rights reserved.
   4 */
   5
   6#include <linux/device.h>
   7#include <linux/dma-mapping.h>
   8#include <linux/interrupt.h>
   9#include <linux/moduleparam.h>
  10#include <linux/types.h>
  11#include <linux/errno.h>
  12#include <crypto/aes.h>
  13#include <crypto/internal/des.h>
  14#include <crypto/internal/skcipher.h>
  15
  16#include "cipher.h"
  17
  18static unsigned int aes_sw_max_len = CONFIG_CRYPTO_DEV_QCE_SW_MAX_LEN;
  19module_param(aes_sw_max_len, uint, 0644);
  20MODULE_PARM_DESC(aes_sw_max_len,
  21                 "Only use hardware for AES requests larger than this "
  22                 "[0=always use hardware; anything <16 breaks AES-GCM; default="
  23                 __stringify(CONFIG_CRYPTO_DEV_QCE_SW_MAX_LEN)"]");
  24
  25static LIST_HEAD(skcipher_algs);
  26
  27static void qce_skcipher_done(void *data)
  28{
  29        struct crypto_async_request *async_req = data;
  30        struct skcipher_request *req = skcipher_request_cast(async_req);
  31        struct qce_cipher_reqctx *rctx = skcipher_request_ctx(req);
  32        struct qce_alg_template *tmpl = to_cipher_tmpl(crypto_skcipher_reqtfm(req));
  33        struct qce_device *qce = tmpl->qce;
  34        struct qce_result_dump *result_buf = qce->dma.result_buf;
  35        enum dma_data_direction dir_src, dir_dst;
  36        u32 status;
  37        int error;
  38        bool diff_dst;
  39
  40        diff_dst = (req->src != req->dst) ? true : false;
  41        dir_src = diff_dst ? DMA_TO_DEVICE : DMA_BIDIRECTIONAL;
  42        dir_dst = diff_dst ? DMA_FROM_DEVICE : DMA_BIDIRECTIONAL;
  43
  44        error = qce_dma_terminate_all(&qce->dma);
  45        if (error)
  46                dev_dbg(qce->dev, "skcipher dma termination error (%d)\n",
  47                        error);
  48
  49        if (diff_dst)
  50                dma_unmap_sg(qce->dev, rctx->src_sg, rctx->src_nents, dir_src);
  51        dma_unmap_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);
  52
  53        sg_free_table(&rctx->dst_tbl);
  54
  55        error = qce_check_status(qce, &status);
  56        if (error < 0)
  57                dev_dbg(qce->dev, "skcipher operation error (%x)\n", status);
  58
  59        memcpy(rctx->iv, result_buf->encr_cntr_iv, rctx->ivsize);
  60        qce->async_req_done(tmpl->qce, error);
  61}
  62
  63static int
  64qce_skcipher_async_req_handle(struct crypto_async_request *async_req)
  65{
  66        struct skcipher_request *req = skcipher_request_cast(async_req);
  67        struct qce_cipher_reqctx *rctx = skcipher_request_ctx(req);
  68        struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
  69        struct qce_alg_template *tmpl = to_cipher_tmpl(crypto_skcipher_reqtfm(req));
  70        struct qce_device *qce = tmpl->qce;
  71        enum dma_data_direction dir_src, dir_dst;
  72        struct scatterlist *sg;
  73        bool diff_dst;
  74        gfp_t gfp;
  75        int dst_nents, src_nents, ret;
  76
  77        rctx->iv = req->iv;
  78        rctx->ivsize = crypto_skcipher_ivsize(skcipher);
  79        rctx->cryptlen = req->cryptlen;
  80
  81        diff_dst = (req->src != req->dst) ? true : false;
  82        dir_src = diff_dst ? DMA_TO_DEVICE : DMA_BIDIRECTIONAL;
  83        dir_dst = diff_dst ? DMA_FROM_DEVICE : DMA_BIDIRECTIONAL;
  84
  85        rctx->src_nents = sg_nents_for_len(req->src, req->cryptlen);
  86        if (diff_dst)
  87                rctx->dst_nents = sg_nents_for_len(req->dst, req->cryptlen);
  88        else
  89                rctx->dst_nents = rctx->src_nents;
  90        if (rctx->src_nents < 0) {
  91                dev_err(qce->dev, "Invalid numbers of src SG.\n");
  92                return rctx->src_nents;
  93        }
  94        if (rctx->dst_nents < 0) {
  95                dev_err(qce->dev, "Invalid numbers of dst SG.\n");
  96                return -rctx->dst_nents;
  97        }
  98
  99        rctx->dst_nents += 1;
 100
 101        gfp = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
 102                                                GFP_KERNEL : GFP_ATOMIC;
 103
 104        ret = sg_alloc_table(&rctx->dst_tbl, rctx->dst_nents, gfp);
 105        if (ret)
 106                return ret;
 107
 108        sg_init_one(&rctx->result_sg, qce->dma.result_buf, QCE_RESULT_BUF_SZ);
 109
 110        sg = qce_sgtable_add(&rctx->dst_tbl, req->dst, req->cryptlen);
 111        if (IS_ERR(sg)) {
 112                ret = PTR_ERR(sg);
 113                goto error_free;
 114        }
 115
 116        sg = qce_sgtable_add(&rctx->dst_tbl, &rctx->result_sg,
 117                             QCE_RESULT_BUF_SZ);
 118        if (IS_ERR(sg)) {
 119                ret = PTR_ERR(sg);
 120                goto error_free;
 121        }
 122
 123        sg_mark_end(sg);
 124        rctx->dst_sg = rctx->dst_tbl.sgl;
 125
 126        dst_nents = dma_map_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);
 127        if (dst_nents < 0) {
 128                ret = dst_nents;
 129                goto error_free;
 130        }
 131
 132        if (diff_dst) {
 133                src_nents = dma_map_sg(qce->dev, req->src, rctx->src_nents, dir_src);
 134                if (src_nents < 0) {
 135                        ret = src_nents;
 136                        goto error_unmap_dst;
 137                }
 138                rctx->src_sg = req->src;
 139        } else {
 140                rctx->src_sg = rctx->dst_sg;
 141                src_nents = dst_nents - 1;
 142        }
 143
 144        ret = qce_dma_prep_sgs(&qce->dma, rctx->src_sg, src_nents,
 145                               rctx->dst_sg, dst_nents,
 146                               qce_skcipher_done, async_req);
 147        if (ret)
 148                goto error_unmap_src;
 149
 150        qce_dma_issue_pending(&qce->dma);
 151
 152        ret = qce_start(async_req, tmpl->crypto_alg_type);
 153        if (ret)
 154                goto error_terminate;
 155
 156        return 0;
 157
 158error_terminate:
 159        qce_dma_terminate_all(&qce->dma);
 160error_unmap_src:
 161        if (diff_dst)
 162                dma_unmap_sg(qce->dev, req->src, rctx->src_nents, dir_src);
 163error_unmap_dst:
 164        dma_unmap_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);
 165error_free:
 166        sg_free_table(&rctx->dst_tbl);
 167        return ret;
 168}
 169
 170static int qce_skcipher_setkey(struct crypto_skcipher *ablk, const u8 *key,
 171                                 unsigned int keylen)
 172{
 173        struct crypto_tfm *tfm = crypto_skcipher_tfm(ablk);
 174        struct qce_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
 175        unsigned long flags = to_cipher_tmpl(ablk)->alg_flags;
 176        unsigned int __keylen;
 177        int ret;
 178
 179        if (!key || !keylen)
 180                return -EINVAL;
 181
 182        /*
 183         * AES XTS key1 = key2 not supported by crypto engine.
 184         * Revisit to request a fallback cipher in this case.
 185         */
 186        if (IS_XTS(flags)) {
 187                __keylen = keylen >> 1;
 188                if (!memcmp(key, key + __keylen, __keylen))
 189                        return -ENOKEY;
 190        } else {
 191                __keylen = keylen;
 192        }
 193
 194        switch (__keylen) {
 195        case AES_KEYSIZE_128:
 196        case AES_KEYSIZE_256:
 197                memcpy(ctx->enc_key, key, keylen);
 198                break;
 199        case AES_KEYSIZE_192:
 200                break;
 201        default:
 202                return -EINVAL;
 203        }
 204
 205        ret = crypto_skcipher_setkey(ctx->fallback, key, keylen);
 206        if (!ret)
 207                ctx->enc_keylen = keylen;
 208        return ret;
 209}
 210
 211static int qce_des_setkey(struct crypto_skcipher *ablk, const u8 *key,
 212                          unsigned int keylen)
 213{
 214        struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(ablk);
 215        int err;
 216
 217        err = verify_skcipher_des_key(ablk, key);
 218        if (err)
 219                return err;
 220
 221        ctx->enc_keylen = keylen;
 222        memcpy(ctx->enc_key, key, keylen);
 223        return 0;
 224}
 225
 226static int qce_des3_setkey(struct crypto_skcipher *ablk, const u8 *key,
 227                           unsigned int keylen)
 228{
 229        struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(ablk);
 230        u32 _key[6];
 231        int err;
 232
 233        err = verify_skcipher_des3_key(ablk, key);
 234        if (err)
 235                return err;
 236
 237        /*
 238         * The crypto engine does not support any two keys
 239         * being the same for triple des algorithms. The
 240         * verify_skcipher_des3_key does not check for all the
 241         * below conditions. Return -ENOKEY in case any two keys
 242         * are the same. Revisit to see if a fallback cipher
 243         * is needed to handle this condition.
 244         */
 245        memcpy(_key, key, DES3_EDE_KEY_SIZE);
 246        if (!((_key[0] ^ _key[2]) | (_key[1] ^ _key[3])) ||
 247            !((_key[2] ^ _key[4]) | (_key[3] ^ _key[5])) ||
 248            !((_key[0] ^ _key[4]) | (_key[1] ^ _key[5])))
 249                return -ENOKEY;
 250
 251        ctx->enc_keylen = keylen;
 252        memcpy(ctx->enc_key, key, keylen);
 253        return 0;
 254}
 255
 256static int qce_skcipher_crypt(struct skcipher_request *req, int encrypt)
 257{
 258        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 259        struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 260        struct qce_cipher_reqctx *rctx = skcipher_request_ctx(req);
 261        struct qce_alg_template *tmpl = to_cipher_tmpl(tfm);
 262        unsigned int blocksize = crypto_skcipher_blocksize(tfm);
 263        int keylen;
 264        int ret;
 265
 266        rctx->flags = tmpl->alg_flags;
 267        rctx->flags |= encrypt ? QCE_ENCRYPT : QCE_DECRYPT;
 268        keylen = IS_XTS(rctx->flags) ? ctx->enc_keylen >> 1 : ctx->enc_keylen;
 269
 270        /* CE does not handle 0 length messages */
 271        if (!req->cryptlen)
 272                return 0;
 273
 274        /*
 275         * ECB and CBC algorithms require message lengths to be
 276         * multiples of block size.
 277         */
 278        if (IS_ECB(rctx->flags) || IS_CBC(rctx->flags))
 279                if (!IS_ALIGNED(req->cryptlen, blocksize))
 280                        return -EINVAL;
 281
 282        /*
 283         * Conditions for requesting a fallback cipher
 284         * AES-192 (not supported by crypto engine (CE))
 285         * AES-XTS request with len <= 512 byte (not recommended to use CE)
 286         * AES-XTS request with len > QCE_SECTOR_SIZE and
 287         * is not a multiple of it.(Revisit this condition to check if it is
 288         * needed in all versions of CE)
 289         */
 290        if (IS_AES(rctx->flags) &&
 291            ((keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_256) ||
 292            (IS_XTS(rctx->flags) && ((req->cryptlen <= aes_sw_max_len) ||
 293            (req->cryptlen > QCE_SECTOR_SIZE &&
 294            req->cryptlen % QCE_SECTOR_SIZE))))) {
 295                skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback);
 296                skcipher_request_set_callback(&rctx->fallback_req,
 297                                              req->base.flags,
 298                                              req->base.complete,
 299                                              req->base.data);
 300                skcipher_request_set_crypt(&rctx->fallback_req, req->src,
 301                                           req->dst, req->cryptlen, req->iv);
 302                ret = encrypt ? crypto_skcipher_encrypt(&rctx->fallback_req) :
 303                                crypto_skcipher_decrypt(&rctx->fallback_req);
 304                return ret;
 305        }
 306
 307        return tmpl->qce->async_req_enqueue(tmpl->qce, &req->base);
 308}
 309
 310static int qce_skcipher_encrypt(struct skcipher_request *req)
 311{
 312        return qce_skcipher_crypt(req, 1);
 313}
 314
 315static int qce_skcipher_decrypt(struct skcipher_request *req)
 316{
 317        return qce_skcipher_crypt(req, 0);
 318}
 319
 320static int qce_skcipher_init(struct crypto_skcipher *tfm)
 321{
 322        /* take the size without the fallback skcipher_request at the end */
 323        crypto_skcipher_set_reqsize(tfm, offsetof(struct qce_cipher_reqctx,
 324                                                  fallback_req));
 325        return 0;
 326}
 327
 328static int qce_skcipher_init_fallback(struct crypto_skcipher *tfm)
 329{
 330        struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 331
 332        ctx->fallback = crypto_alloc_skcipher(crypto_tfm_alg_name(&tfm->base),
 333                                              0, CRYPTO_ALG_NEED_FALLBACK);
 334        if (IS_ERR(ctx->fallback))
 335                return PTR_ERR(ctx->fallback);
 336
 337        crypto_skcipher_set_reqsize(tfm, sizeof(struct qce_cipher_reqctx) +
 338                                         crypto_skcipher_reqsize(ctx->fallback));
 339        return 0;
 340}
 341
 342static void qce_skcipher_exit(struct crypto_skcipher *tfm)
 343{
 344        struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 345
 346        crypto_free_skcipher(ctx->fallback);
 347}
 348
 349struct qce_skcipher_def {
 350        unsigned long flags;
 351        const char *name;
 352        const char *drv_name;
 353        unsigned int blocksize;
 354        unsigned int chunksize;
 355        unsigned int ivsize;
 356        unsigned int min_keysize;
 357        unsigned int max_keysize;
 358};
 359
 360static const struct qce_skcipher_def skcipher_def[] = {
 361        {
 362                .flags          = QCE_ALG_AES | QCE_MODE_ECB,
 363                .name           = "ecb(aes)",
 364                .drv_name       = "ecb-aes-qce",
 365                .blocksize      = AES_BLOCK_SIZE,
 366                .ivsize         = 0,
 367                .min_keysize    = AES_MIN_KEY_SIZE,
 368                .max_keysize    = AES_MAX_KEY_SIZE,
 369        },
 370        {
 371                .flags          = QCE_ALG_AES | QCE_MODE_CBC,
 372                .name           = "cbc(aes)",
 373                .drv_name       = "cbc-aes-qce",
 374                .blocksize      = AES_BLOCK_SIZE,
 375                .ivsize         = AES_BLOCK_SIZE,
 376                .min_keysize    = AES_MIN_KEY_SIZE,
 377                .max_keysize    = AES_MAX_KEY_SIZE,
 378        },
 379        {
 380                .flags          = QCE_ALG_AES | QCE_MODE_CTR,
 381                .name           = "ctr(aes)",
 382                .drv_name       = "ctr-aes-qce",
 383                .blocksize      = 1,
 384                .chunksize      = AES_BLOCK_SIZE,
 385                .ivsize         = AES_BLOCK_SIZE,
 386                .min_keysize    = AES_MIN_KEY_SIZE,
 387                .max_keysize    = AES_MAX_KEY_SIZE,
 388        },
 389        {
 390                .flags          = QCE_ALG_AES | QCE_MODE_XTS,
 391                .name           = "xts(aes)",
 392                .drv_name       = "xts-aes-qce",
 393                .blocksize      = AES_BLOCK_SIZE,
 394                .ivsize         = AES_BLOCK_SIZE,
 395                .min_keysize    = AES_MIN_KEY_SIZE * 2,
 396                .max_keysize    = AES_MAX_KEY_SIZE * 2,
 397        },
 398        {
 399                .flags          = QCE_ALG_DES | QCE_MODE_ECB,
 400                .name           = "ecb(des)",
 401                .drv_name       = "ecb-des-qce",
 402                .blocksize      = DES_BLOCK_SIZE,
 403                .ivsize         = 0,
 404                .min_keysize    = DES_KEY_SIZE,
 405                .max_keysize    = DES_KEY_SIZE,
 406        },
 407        {
 408                .flags          = QCE_ALG_DES | QCE_MODE_CBC,
 409                .name           = "cbc(des)",
 410                .drv_name       = "cbc-des-qce",
 411                .blocksize      = DES_BLOCK_SIZE,
 412                .ivsize         = DES_BLOCK_SIZE,
 413                .min_keysize    = DES_KEY_SIZE,
 414                .max_keysize    = DES_KEY_SIZE,
 415        },
 416        {
 417                .flags          = QCE_ALG_3DES | QCE_MODE_ECB,
 418                .name           = "ecb(des3_ede)",
 419                .drv_name       = "ecb-3des-qce",
 420                .blocksize      = DES3_EDE_BLOCK_SIZE,
 421                .ivsize         = 0,
 422                .min_keysize    = DES3_EDE_KEY_SIZE,
 423                .max_keysize    = DES3_EDE_KEY_SIZE,
 424        },
 425        {
 426                .flags          = QCE_ALG_3DES | QCE_MODE_CBC,
 427                .name           = "cbc(des3_ede)",
 428                .drv_name       = "cbc-3des-qce",
 429                .blocksize      = DES3_EDE_BLOCK_SIZE,
 430                .ivsize         = DES3_EDE_BLOCK_SIZE,
 431                .min_keysize    = DES3_EDE_KEY_SIZE,
 432                .max_keysize    = DES3_EDE_KEY_SIZE,
 433        },
 434};
 435
 436static int qce_skcipher_register_one(const struct qce_skcipher_def *def,
 437                                       struct qce_device *qce)
 438{
 439        struct qce_alg_template *tmpl;
 440        struct skcipher_alg *alg;
 441        int ret;
 442
 443        tmpl = kzalloc(sizeof(*tmpl), GFP_KERNEL);
 444        if (!tmpl)
 445                return -ENOMEM;
 446
 447        alg = &tmpl->alg.skcipher;
 448
 449        snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 450        snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 451                 def->drv_name);
 452
 453        alg->base.cra_blocksize         = def->blocksize;
 454        alg->chunksize                  = def->chunksize;
 455        alg->ivsize                     = def->ivsize;
 456        alg->min_keysize                = def->min_keysize;
 457        alg->max_keysize                = def->max_keysize;
 458        alg->setkey                     = IS_3DES(def->flags) ? qce_des3_setkey :
 459                                          IS_DES(def->flags) ? qce_des_setkey :
 460                                          qce_skcipher_setkey;
 461        alg->encrypt                    = qce_skcipher_encrypt;
 462        alg->decrypt                    = qce_skcipher_decrypt;
 463
 464        alg->base.cra_priority          = 300;
 465        alg->base.cra_flags             = CRYPTO_ALG_ASYNC |
 466                                          CRYPTO_ALG_ALLOCATES_MEMORY |
 467                                          CRYPTO_ALG_KERN_DRIVER_ONLY;
 468        alg->base.cra_ctxsize           = sizeof(struct qce_cipher_ctx);
 469        alg->base.cra_alignmask         = 0;
 470        alg->base.cra_module            = THIS_MODULE;
 471
 472        if (IS_AES(def->flags)) {
 473                alg->base.cra_flags    |= CRYPTO_ALG_NEED_FALLBACK;
 474                alg->init               = qce_skcipher_init_fallback;
 475                alg->exit               = qce_skcipher_exit;
 476        } else {
 477                alg->init               = qce_skcipher_init;
 478        }
 479
 480        INIT_LIST_HEAD(&tmpl->entry);
 481        tmpl->crypto_alg_type = CRYPTO_ALG_TYPE_SKCIPHER;
 482        tmpl->alg_flags = def->flags;
 483        tmpl->qce = qce;
 484
 485        ret = crypto_register_skcipher(alg);
 486        if (ret) {
 487                kfree(tmpl);
 488                dev_err(qce->dev, "%s registration failed\n", alg->base.cra_name);
 489                return ret;
 490        }
 491
 492        list_add_tail(&tmpl->entry, &skcipher_algs);
 493        dev_dbg(qce->dev, "%s is registered\n", alg->base.cra_name);
 494        return 0;
 495}
 496
 497static void qce_skcipher_unregister(struct qce_device *qce)
 498{
 499        struct qce_alg_template *tmpl, *n;
 500
 501        list_for_each_entry_safe(tmpl, n, &skcipher_algs, entry) {
 502                crypto_unregister_skcipher(&tmpl->alg.skcipher);
 503                list_del(&tmpl->entry);
 504                kfree(tmpl);
 505        }
 506}
 507
 508static int qce_skcipher_register(struct qce_device *qce)
 509{
 510        int ret, i;
 511
 512        for (i = 0; i < ARRAY_SIZE(skcipher_def); i++) {
 513                ret = qce_skcipher_register_one(&skcipher_def[i], qce);
 514                if (ret)
 515                        goto err;
 516        }
 517
 518        return 0;
 519err:
 520        qce_skcipher_unregister(qce);
 521        return ret;
 522}
 523
 524const struct qce_algo_ops skcipher_ops = {
 525        .type = CRYPTO_ALG_TYPE_SKCIPHER,
 526        .register_algs = qce_skcipher_register,
 527        .unregister_algs = qce_skcipher_unregister,
 528        .async_req_handle = qce_skcipher_async_req_handle,
 529};
 530