drivers/crypto/ccp/ccp-crypto-sha.c

   1 /*
   2  * AMD Cryptographic Coprocessor (CCP) SHA crypto API support
   3  *
   4  * Copyright (C) 2013,2017 Advanced Micro Devices, Inc.
   5  *
   6  * Author: Tom Lendacky <thomas.lendacky@amd.com>
   7  * Author: Gary R Hook <gary.hook@amd.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/sched.h>
  16 #include <linux/delay.h>
  17 #include <linux/scatterlist.h>
  18 #include <linux/crypto.h>
  19 #include <crypto/algapi.h>
  20 #include <crypto/hash.h>
  21 #include <crypto/hmac.h>
  22 #include <crypto/internal/hash.h>
  23 #include <crypto/sha.h>
  24 #include <crypto/scatterwalk.h>
  25
  26 #include "ccp-crypto.h"
  27
  28 static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
  29 {
  30         struct ahash_request *req = ahash_request_cast(async_req);
  31         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
  32         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
  33         unsigned int digest_size = crypto_ahash_digestsize(tfm);
  34
  35         if (ret)
  36                 goto e_free;
  37
  38         if (rctx->hash_rem) {
  39                 /* Save remaining data to buffer */
  40                 unsigned int offset = rctx->nbytes - rctx->hash_rem;
  41
  42                 scatterwalk_map_and_copy(rctx->buf, rctx->src,
  43                                          offset, rctx->hash_rem, 0);
  44                 rctx->buf_count = rctx->hash_rem;
  45         } else {
  46                 rctx->buf_count = 0;
  47         }
  48
  49         /* Update result area if supplied */
  50         if (req->result && rctx->final)
  51                 memcpy(req->result, rctx->ctx, digest_size);
  52
  53 e_free:
  54         sg_free_table(&rctx->data_sg);
  55
  56         return ret;
  57 }
  58
  59 static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
  60                              unsigned int final)
  61 {
  62         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
  63         struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
  64         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
  65         struct scatterlist *sg;
  66         unsigned int block_size =
  67                 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
  68         unsigned int sg_count;
  69         gfp_t gfp;
  70         u64 len;
  71         int ret;
  72
  73         len = (u64)rctx->buf_count + (u64)nbytes;
  74
  75         if (!final && (len <= block_size)) {
  76                 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
  77                                          0, nbytes, 0);
  78                 rctx->buf_count += nbytes;
  79
  80                 return 0;
  81         }
  82
  83         rctx->src = req->src;
  84         rctx->nbytes = nbytes;
  85
  86         rctx->final = final;
  87         rctx->hash_rem = final ? 0 : len & (block_size - 1);
  88         rctx->hash_cnt = len - rctx->hash_rem;
  89         if (!final && !rctx->hash_rem) {
  90                 /* CCP can't do zero length final, so keep some data around */
  91                 rctx->hash_cnt -= block_size;
  92                 rctx->hash_rem = block_size;
  93         }
  94
  95         /* Initialize the context scatterlist */
  96         sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx));
  97
  98         sg = NULL;
  99         if (rctx->buf_count && nbytes) {
 100                 /* Build the data scatterlist table - allocate enough entries
 101                  * for both data pieces (buffer and input data)
 102                  */
 103                 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
 104                         GFP_KERNEL : GFP_ATOMIC;
 105                 sg_count = sg_nents(req->src) + 1;
 106                 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp);
 107                 if (ret)
 108                         return ret;
 109
 110                 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
 111                 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);
 112                 if (!sg) {
 113                         ret = -EINVAL;
 114                         goto e_free;
 115                 }
 116                 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);
 117                 if (!sg) {
 118                         ret = -EINVAL;
 119                         goto e_free;
 120                 }
 121                 sg_mark_end(sg);
 122
 123                 sg = rctx->data_sg.sgl;
 124         } else if (rctx->buf_count) {
 125                 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
 126
 127                 sg = &rctx->buf_sg;
 128         } else if (nbytes) {
 129                 sg = req->src;
 130         }
 131
 132         rctx->msg_bits += (rctx->hash_cnt << 3);        /* Total in bits */
 133
 134         memset(&rctx->cmd, 0, sizeof(rctx->cmd));
 135         INIT_LIST_HEAD(&rctx->cmd.entry);
 136         rctx->cmd.engine = CCP_ENGINE_SHA;
 137         rctx->cmd.u.sha.type = rctx->type;
 138         rctx->cmd.u.sha.ctx = &rctx->ctx_sg;
 139
 140         switch (rctx->type) {
 141         case CCP_SHA_TYPE_1:
 142                 rctx->cmd.u.sha.ctx_len = SHA1_DIGEST_SIZE;
 143                 break;
 144         case CCP_SHA_TYPE_224:
 145                 rctx->cmd.u.sha.ctx_len = SHA224_DIGEST_SIZE;
 146                 break;
 147         case CCP_SHA_TYPE_256:
 148                 rctx->cmd.u.sha.ctx_len = SHA256_DIGEST_SIZE;
 149                 break;
 150         case CCP_SHA_TYPE_384:
 151                 rctx->cmd.u.sha.ctx_len = SHA384_DIGEST_SIZE;
 152                 break;
 153         case CCP_SHA_TYPE_512:
 154                 rctx->cmd.u.sha.ctx_len = SHA512_DIGEST_SIZE;
 155                 break;
 156         default:
 157                 /* Should never get here */
 158                 break;
 159         }
 160
 161         rctx->cmd.u.sha.src = sg;
 162         rctx->cmd.u.sha.src_len = rctx->hash_cnt;
 163         rctx->cmd.u.sha.opad = ctx->u.sha.key_len ?
 164                 &ctx->u.sha.opad_sg : NULL;
 165         rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ?
 166                 ctx->u.sha.opad_count : 0;
 167         rctx->cmd.u.sha.first = rctx->first;
 168         rctx->cmd.u.sha.final = rctx->final;
 169         rctx->cmd.u.sha.msg_bits = rctx->msg_bits;
 170
 171         rctx->first = 0;
 172
 173         ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
 174
 175         return ret;
 176
 177 e_free:
 178         sg_free_table(&rctx->data_sg);
 179
 180         return ret;
 181 }
 182
 183 static int ccp_sha_init(struct ahash_request *req)
 184 {
 185         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 186         struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
 187         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 188         struct ccp_crypto_ahash_alg *alg =
 189                 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));
 190         unsigned int block_size =
 191                 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
 192
 193         memset(rctx, 0, sizeof(*rctx));
 194
 195         rctx->type = alg->type;
 196         rctx->first = 1;
 197
 198         if (ctx->u.sha.key_len) {
 199                 /* Buffer the HMAC key for first update */
 200                 memcpy(rctx->buf, ctx->u.sha.ipad, block_size);
 201                 rctx->buf_count = block_size;
 202         }
 203
 204         return 0;
 205 }
 206
 207 static int ccp_sha_update(struct ahash_request *req)
 208 {
 209         return ccp_do_sha_update(req, req->nbytes, 0);
 210 }
 211
 212 static int ccp_sha_final(struct ahash_request *req)
 213 {
 214         return ccp_do_sha_update(req, 0, 1);
 215 }
 216
 217 static int ccp_sha_finup(struct ahash_request *req)
 218 {
 219         return ccp_do_sha_update(req, req->nbytes, 1);
 220 }
 221
 222 static int ccp_sha_digest(struct ahash_request *req)
 223 {
 224         int ret;
 225
 226         ret = ccp_sha_init(req);
 227         if (ret)
 228                 return ret;
 229
 230         return ccp_sha_finup(req);
 231 }
 232
 233 static int ccp_sha_export(struct ahash_request *req, void *out)
 234 {
 235         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 236         struct ccp_sha_exp_ctx state;
 237
 238         /* Don't let anything leak to 'out' */
 239         memset(&state, 0, sizeof(state));
 240
 241         state.type = rctx->type;
 242         state.msg_bits = rctx->msg_bits;
 243         state.first = rctx->first;
 244         memcpy(state.ctx, rctx->ctx, sizeof(state.ctx));
 245         state.buf_count = rctx->buf_count;
 246         memcpy(state.buf, rctx->buf, sizeof(state.buf));
 247
 248         /* 'out' may not be aligned so memcpy from local variable */
 249         memcpy(out, &state, sizeof(state));
 250
 251         return 0;
 252 }
 253
 254 static int ccp_sha_import(struct ahash_request *req, const void *in)
 255 {
 256         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 257         struct ccp_sha_exp_ctx state;
 258
 259         /* 'in' may not be aligned so memcpy to local variable */
 260         memcpy(&state, in, sizeof(state));
 261
 262         memset(rctx, 0, sizeof(*rctx));
 263         rctx->type = state.type;
 264         rctx->msg_bits = state.msg_bits;
 265         rctx->first = state.first;
 266         memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx));
 267         rctx->buf_count = state.buf_count;
 268         memcpy(rctx->buf, state.buf, sizeof(rctx->buf));
 269
 270         return 0;
 271 }
 272
 273 static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
 274                           unsigned int key_len)
 275 {
 276         struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
 277         struct crypto_shash *shash = ctx->u.sha.hmac_tfm;
 278
 279         SHASH_DESC_ON_STACK(sdesc, shash);
 280
 281         unsigned int block_size = crypto_shash_blocksize(shash);
 282         unsigned int digest_size = crypto_shash_digestsize(shash);
 283         int i, ret;
 284
 285         /* Set to zero until complete */
 286         ctx->u.sha.key_len = 0;
 287
 288         /* Clear key area to provide zero padding for keys smaller
 289          * than the block size
 290          */
 291         memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key));
 292
 293         if (key_len > block_size) {
 294                 /* Must hash the input key */
 295                 sdesc->tfm = shash;
 296                 sdesc->flags = crypto_ahash_get_flags(tfm) &
 297                         CRYPTO_TFM_REQ_MAY_SLEEP;
 298
 299                 ret = crypto_shash_digest(sdesc, key, key_len,
 300                                           ctx->u.sha.key);
 301                 if (ret) {
 302                         crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 303                         return -EINVAL;
 304                 }
 305
 306                 key_len = digest_size;
 307         } else {
 308                 memcpy(ctx->u.sha.key, key, key_len);
 309         }
 310
 311         for (i = 0; i < block_size; i++) {
 312                 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ HMAC_IPAD_VALUE;
 313                 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ HMAC_OPAD_VALUE;
 314         }
 315
 316         sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size);
 317         ctx->u.sha.opad_count = block_size;
 318
 319         ctx->u.sha.key_len = key_len;
 320
 321         return 0;
 322 }
 323
 324 static int ccp_sha_cra_init(struct crypto_tfm *tfm)
 325 {
 326         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 327         struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);
 328
 329         ctx->complete = ccp_sha_complete;
 330         ctx->u.sha.key_len = 0;
 331
 332         crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx));
 333
 334         return 0;
 335 }
 336
 337 static void ccp_sha_cra_exit(struct crypto_tfm *tfm)
 338 {
 339 }
 340
 341 static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm)
 342 {
 343         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 344         struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm);
 345         struct crypto_shash *hmac_tfm;
 346
 347         hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0);
 348         if (IS_ERR(hmac_tfm)) {
 349                 pr_warn("could not load driver %s need for HMAC support\n",
 350                         alg->child_alg);
 351                 return PTR_ERR(hmac_tfm);
 352         }
 353
 354         ctx->u.sha.hmac_tfm = hmac_tfm;
 355
 356         return ccp_sha_cra_init(tfm);
 357 }
 358
 359 static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm)
 360 {
 361         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 362
 363         if (ctx->u.sha.hmac_tfm)
 364                 crypto_free_shash(ctx->u.sha.hmac_tfm);
 365
 366         ccp_sha_cra_exit(tfm);
 367 }
 368
 369 struct ccp_sha_def {
 370         unsigned int version;
 371         const char *name;
 372         const char *drv_name;
 373         enum ccp_sha_type type;
 374         u32 digest_size;
 375         u32 block_size;
 376 };
 377
 378 static struct ccp_sha_def sha_algs[] = {
 379         {
 380                 .version        = CCP_VERSION(3, 0),
 381                 .name           = "sha1",
 382                 .drv_name       = "sha1-ccp",
 383                 .type           = CCP_SHA_TYPE_1,
 384                 .digest_size    = SHA1_DIGEST_SIZE,
 385                 .block_size     = SHA1_BLOCK_SIZE,
 386         },
 387         {
 388                 .version        = CCP_VERSION(3, 0),
 389                 .name           = "sha224",
 390                 .drv_name       = "sha224-ccp",
 391                 .type           = CCP_SHA_TYPE_224,
 392                 .digest_size    = SHA224_DIGEST_SIZE,
 393                 .block_size     = SHA224_BLOCK_SIZE,
 394         },
 395         {
 396                 .version        = CCP_VERSION(3, 0),
 397                 .name           = "sha256",
 398                 .drv_name       = "sha256-ccp",
 399                 .type           = CCP_SHA_TYPE_256,
 400                 .digest_size    = SHA256_DIGEST_SIZE,
 401                 .block_size     = SHA256_BLOCK_SIZE,
 402         },
 403         {
 404                 .version        = CCP_VERSION(5, 0),
 405                 .name           = "sha384",
 406                 .drv_name       = "sha384-ccp",
 407                 .type           = CCP_SHA_TYPE_384,
 408                 .digest_size    = SHA384_DIGEST_SIZE,
 409                 .block_size     = SHA384_BLOCK_SIZE,
 410         },
 411         {
 412                 .version        = CCP_VERSION(5, 0),
 413                 .name           = "sha512",
 414                 .drv_name       = "sha512-ccp",
 415                 .type           = CCP_SHA_TYPE_512,
 416                 .digest_size    = SHA512_DIGEST_SIZE,
 417                 .block_size     = SHA512_BLOCK_SIZE,
 418         },
 419 };
 420
 421 static int ccp_register_hmac_alg(struct list_head *head,
 422                                  const struct ccp_sha_def *def,
 423                                  const struct ccp_crypto_ahash_alg *base_alg)
 424 {
 425         struct ccp_crypto_ahash_alg *ccp_alg;
 426         struct ahash_alg *alg;
 427         struct hash_alg_common *halg;
 428         struct crypto_alg *base;
 429         int ret;
 430
 431         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 432         if (!ccp_alg)
 433                 return -ENOMEM;
 434
 435         /* Copy the base algorithm and only change what's necessary */
 436         *ccp_alg = *base_alg;
 437         INIT_LIST_HEAD(&ccp_alg->entry);
 438
 439         strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME);
 440
 441         alg = &ccp_alg->alg;
 442         alg->setkey = ccp_sha_setkey;
 443
 444         halg = &alg->halg;
 445
 446         base = &halg->base;
 447         snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name);
 448         snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s",
 449                  def->drv_name);
 450         base->cra_init = ccp_hmac_sha_cra_init;
 451         base->cra_exit = ccp_hmac_sha_cra_exit;
 452
 453         ret = crypto_register_ahash(alg);
 454         if (ret) {
 455                 pr_err("%s ahash algorithm registration error (%d)\n",
 456                        base->cra_name, ret);
 457                 kfree(ccp_alg);
 458                 return ret;
 459         }
 460
 461         list_add(&ccp_alg->entry, head);
 462
 463         return ret;
 464 }
 465
 466 static int ccp_register_sha_alg(struct list_head *head,
 467                                 const struct ccp_sha_def *def)
 468 {
 469         struct ccp_crypto_ahash_alg *ccp_alg;
 470         struct ahash_alg *alg;
 471         struct hash_alg_common *halg;
 472         struct crypto_alg *base;
 473         int ret;
 474
 475         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 476         if (!ccp_alg)
 477                 return -ENOMEM;
 478
 479         INIT_LIST_HEAD(&ccp_alg->entry);
 480
 481         ccp_alg->type = def->type;
 482
 483         alg = &ccp_alg->alg;
 484         alg->init = ccp_sha_init;
 485         alg->update = ccp_sha_update;
 486         alg->final = ccp_sha_final;
 487         alg->finup = ccp_sha_finup;
 488         alg->digest = ccp_sha_digest;
 489         alg->export = ccp_sha_export;
 490         alg->import = ccp_sha_import;
 491
 492         halg = &alg->halg;
 493         halg->digestsize = def->digest_size;
 494         halg->statesize = sizeof(struct ccp_sha_exp_ctx);
 495
 496         base = &halg->base;
 497         snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 498         snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 499                  def->drv_name);
 500         base->cra_flags = CRYPTO_ALG_ASYNC |
 501                           CRYPTO_ALG_KERN_DRIVER_ONLY |
 502                           CRYPTO_ALG_NEED_FALLBACK;
 503         base->cra_blocksize = def->block_size;
 504         base->cra_ctxsize = sizeof(struct ccp_ctx);
 505         base->cra_priority = CCP_CRA_PRIORITY;
 506         base->cra_init = ccp_sha_cra_init;
 507         base->cra_exit = ccp_sha_cra_exit;
 508         base->cra_module = THIS_MODULE;
 509
 510         ret = crypto_register_ahash(alg);
 511         if (ret) {
 512                 pr_err("%s ahash algorithm registration error (%d)\n",
 513                        base->cra_name, ret);
 514                 kfree(ccp_alg);
 515                 return ret;
 516         }
 517
 518         list_add(&ccp_alg->entry, head);
 519
 520         ret = ccp_register_hmac_alg(head, def, ccp_alg);
 521
 522         return ret;
 523 }
 524
 525 int ccp_register_sha_algs(struct list_head *head)
 526 {
 527         int i, ret;
 528         unsigned int ccpversion = ccp_version();
 529
 530         for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
 531                 if (sha_algs[i].version > ccpversion)
 532                         continue;
 533                 ret = ccp_register_sha_alg(head, &sha_algs[i]);
 534                 if (ret)
 535                         return ret;
 536         }
 537
 538         return 0;
 539 }