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

   1 /*
   2  * AMD Cryptographic Coprocessor (CCP) SHA crypto API support
   3  *
   4  * Copyright (C) 2013,2016 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/internal/hash.h>
  22 #include <crypto/sha.h>
  23 #include <crypto/scatterwalk.h>
  24
  25 #include "ccp-crypto.h"
  26
  27 static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
  28 {
  29         struct ahash_request *req = ahash_request_cast(async_req);
  30         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
  31         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
  32         unsigned int digest_size = crypto_ahash_digestsize(tfm);
  33
  34         if (ret)
  35                 goto e_free;
  36
  37         if (rctx->hash_rem) {
  38                 /* Save remaining data to buffer */
  39                 unsigned int offset = rctx->nbytes - rctx->hash_rem;
  40
  41                 scatterwalk_map_and_copy(rctx->buf, rctx->src,
  42                                          offset, rctx->hash_rem, 0);
  43                 rctx->buf_count = rctx->hash_rem;
  44         } else {
  45                 rctx->buf_count = 0;
  46         }
  47
  48         /* Update result area if supplied */
  49         if (req->result)
  50                 memcpy(req->result, rctx->ctx, digest_size);
  51
  52 e_free:
  53         sg_free_table(&rctx->data_sg);
  54
  55         return ret;
  56 }
  57
  58 static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
  59                              unsigned int final)
  60 {
  61         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
  62         struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
  63         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
  64         struct scatterlist *sg;
  65         unsigned int block_size =
  66                 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
  67         unsigned int sg_count;
  68         gfp_t gfp;
  69         u64 len;
  70         int ret;
  71
  72         len = (u64)rctx->buf_count + (u64)nbytes;
  73
  74         if (!final && (len <= block_size)) {
  75                 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
  76                                          0, nbytes, 0);
  77                 rctx->buf_count += nbytes;
  78
  79                 return 0;
  80         }
  81
  82         rctx->src = req->src;
  83         rctx->nbytes = nbytes;
  84
  85         rctx->final = final;
  86         rctx->hash_rem = final ? 0 : len & (block_size - 1);
  87         rctx->hash_cnt = len - rctx->hash_rem;
  88         if (!final && !rctx->hash_rem) {
  89                 /* CCP can't do zero length final, so keep some data around */
  90                 rctx->hash_cnt -= block_size;
  91                 rctx->hash_rem = block_size;
  92         }
  93
  94         /* Initialize the context scatterlist */
  95         sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx));
  96
  97         sg = NULL;
  98         if (rctx->buf_count && nbytes) {
  99                 /* Build the data scatterlist table - allocate enough entries
 100                  * for both data pieces (buffer and input data)
 101                  */
 102                 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
 103                         GFP_KERNEL : GFP_ATOMIC;
 104                 sg_count = sg_nents(req->src) + 1;
 105                 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp);
 106                 if (ret)
 107                         return ret;
 108
 109                 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
 110                 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);
 111                 if (!sg) {
 112                         ret = -EINVAL;
 113                         goto e_free;
 114                 }
 115                 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);
 116                 if (!sg) {
 117                         ret = -EINVAL;
 118                         goto e_free;
 119                 }
 120                 sg_mark_end(sg);
 121
 122                 sg = rctx->data_sg.sgl;
 123         } else if (rctx->buf_count) {
 124                 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
 125
 126                 sg = &rctx->buf_sg;
 127         } else if (nbytes) {
 128                 sg = req->src;
 129         }
 130
 131         rctx->msg_bits += (rctx->hash_cnt << 3);        /* Total in bits */
 132
 133         memset(&rctx->cmd, 0, sizeof(rctx->cmd));
 134         INIT_LIST_HEAD(&rctx->cmd.entry);
 135         rctx->cmd.engine = CCP_ENGINE_SHA;
 136         rctx->cmd.u.sha.type = rctx->type;
 137         rctx->cmd.u.sha.ctx = &rctx->ctx_sg;
 138
 139         switch (rctx->type) {
 140         case CCP_SHA_TYPE_1:
 141                 rctx->cmd.u.sha.ctx_len = SHA1_DIGEST_SIZE;
 142                 break;
 143         case CCP_SHA_TYPE_224:
 144                 rctx->cmd.u.sha.ctx_len = SHA224_DIGEST_SIZE;
 145                 break;
 146         case CCP_SHA_TYPE_256:
 147                 rctx->cmd.u.sha.ctx_len = SHA256_DIGEST_SIZE;
 148                 break;
 149         default:
 150                 /* Should never get here */
 151                 break;
 152         }
 153
 154         rctx->cmd.u.sha.src = sg;
 155         rctx->cmd.u.sha.src_len = rctx->hash_cnt;
 156         rctx->cmd.u.sha.opad = ctx->u.sha.key_len ?
 157                 &ctx->u.sha.opad_sg : NULL;
 158         rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ?
 159                 ctx->u.sha.opad_count : 0;
 160         rctx->cmd.u.sha.first = rctx->first;
 161         rctx->cmd.u.sha.final = rctx->final;
 162         rctx->cmd.u.sha.msg_bits = rctx->msg_bits;
 163
 164         rctx->first = 0;
 165
 166         ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
 167
 168         return ret;
 169
 170 e_free:
 171         sg_free_table(&rctx->data_sg);
 172
 173         return ret;
 174 }
 175
 176 static int ccp_sha_init(struct ahash_request *req)
 177 {
 178         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 179         struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
 180         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 181         struct ccp_crypto_ahash_alg *alg =
 182                 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));
 183         unsigned int block_size =
 184                 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
 185
 186         memset(rctx, 0, sizeof(*rctx));
 187
 188         rctx->type = alg->type;
 189         rctx->first = 1;
 190
 191         if (ctx->u.sha.key_len) {
 192                 /* Buffer the HMAC key for first update */
 193                 memcpy(rctx->buf, ctx->u.sha.ipad, block_size);
 194                 rctx->buf_count = block_size;
 195         }
 196
 197         return 0;
 198 }
 199
 200 static int ccp_sha_update(struct ahash_request *req)
 201 {
 202         return ccp_do_sha_update(req, req->nbytes, 0);
 203 }
 204
 205 static int ccp_sha_final(struct ahash_request *req)
 206 {
 207         return ccp_do_sha_update(req, 0, 1);
 208 }
 209
 210 static int ccp_sha_finup(struct ahash_request *req)
 211 {
 212         return ccp_do_sha_update(req, req->nbytes, 1);
 213 }
 214
 215 static int ccp_sha_digest(struct ahash_request *req)
 216 {
 217         int ret;
 218
 219         ret = ccp_sha_init(req);
 220         if (ret)
 221                 return ret;
 222
 223         return ccp_sha_finup(req);
 224 }
 225
 226 static int ccp_sha_export(struct ahash_request *req, void *out)
 227 {
 228         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 229         struct ccp_sha_exp_ctx state;
 230
 231         /* Don't let anything leak to 'out' */
 232         memset(&state, 0, sizeof(state));
 233
 234         state.type = rctx->type;
 235         state.msg_bits = rctx->msg_bits;
 236         state.first = rctx->first;
 237         memcpy(state.ctx, rctx->ctx, sizeof(state.ctx));
 238         state.buf_count = rctx->buf_count;
 239         memcpy(state.buf, rctx->buf, sizeof(state.buf));
 240
 241         /* 'out' may not be aligned so memcpy from local variable */
 242         memcpy(out, &state, sizeof(state));
 243
 244         return 0;
 245 }
 246
 247 static int ccp_sha_import(struct ahash_request *req, const void *in)
 248 {
 249         struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 250         struct ccp_sha_exp_ctx state;
 251
 252         /* 'in' may not be aligned so memcpy to local variable */
 253         memcpy(&state, in, sizeof(state));
 254
 255         memset(rctx, 0, sizeof(*rctx));
 256         rctx->type = state.type;
 257         rctx->msg_bits = state.msg_bits;
 258         rctx->first = state.first;
 259         memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx));
 260         rctx->buf_count = state.buf_count;
 261         memcpy(rctx->buf, state.buf, sizeof(rctx->buf));
 262
 263         return 0;
 264 }
 265
 266 static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
 267                           unsigned int key_len)
 268 {
 269         struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
 270         struct crypto_shash *shash = ctx->u.sha.hmac_tfm;
 271
 272         SHASH_DESC_ON_STACK(sdesc, shash);
 273
 274         unsigned int block_size = crypto_shash_blocksize(shash);
 275         unsigned int digest_size = crypto_shash_digestsize(shash);
 276         int i, ret;
 277
 278         /* Set to zero until complete */
 279         ctx->u.sha.key_len = 0;
 280
 281         /* Clear key area to provide zero padding for keys smaller
 282          * than the block size
 283          */
 284         memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key));
 285
 286         if (key_len > block_size) {
 287                 /* Must hash the input key */
 288                 sdesc->tfm = shash;
 289                 sdesc->flags = crypto_ahash_get_flags(tfm) &
 290                         CRYPTO_TFM_REQ_MAY_SLEEP;
 291
 292                 ret = crypto_shash_digest(sdesc, key, key_len,
 293                                           ctx->u.sha.key);
 294                 if (ret) {
 295                         crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 296                         return -EINVAL;
 297                 }
 298
 299                 key_len = digest_size;
 300         } else {
 301                 memcpy(ctx->u.sha.key, key, key_len);
 302         }
 303
 304         for (i = 0; i < block_size; i++) {
 305                 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36;
 306                 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c;
 307         }
 308
 309         sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size);
 310         ctx->u.sha.opad_count = block_size;
 311
 312         ctx->u.sha.key_len = key_len;
 313
 314         return 0;
 315 }
 316
 317 static int ccp_sha_cra_init(struct crypto_tfm *tfm)
 318 {
 319         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 320         struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);
 321
 322         ctx->complete = ccp_sha_complete;
 323         ctx->u.sha.key_len = 0;
 324
 325         crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx));
 326
 327         return 0;
 328 }
 329
 330 static void ccp_sha_cra_exit(struct crypto_tfm *tfm)
 331 {
 332 }
 333
 334 static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm)
 335 {
 336         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 337         struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm);
 338         struct crypto_shash *hmac_tfm;
 339
 340         hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0);
 341         if (IS_ERR(hmac_tfm)) {
 342                 pr_warn("could not load driver %s need for HMAC support\n",
 343                         alg->child_alg);
 344                 return PTR_ERR(hmac_tfm);
 345         }
 346
 347         ctx->u.sha.hmac_tfm = hmac_tfm;
 348
 349         return ccp_sha_cra_init(tfm);
 350 }
 351
 352 static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm)
 353 {
 354         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 355
 356         if (ctx->u.sha.hmac_tfm)
 357                 crypto_free_shash(ctx->u.sha.hmac_tfm);
 358
 359         ccp_sha_cra_exit(tfm);
 360 }
 361
 362 struct ccp_sha_def {
 363         unsigned int version;
 364         const char *name;
 365         const char *drv_name;
 366         enum ccp_sha_type type;
 367         u32 digest_size;
 368         u32 block_size;
 369 };
 370
 371 static struct ccp_sha_def sha_algs[] = {
 372         {
 373                 .version        = CCP_VERSION(3, 0),
 374                 .name           = "sha1",
 375                 .drv_name       = "sha1-ccp",
 376                 .type           = CCP_SHA_TYPE_1,
 377                 .digest_size    = SHA1_DIGEST_SIZE,
 378                 .block_size     = SHA1_BLOCK_SIZE,
 379         },
 380         {
 381                 .version        = CCP_VERSION(3, 0),
 382                 .name           = "sha224",
 383                 .drv_name       = "sha224-ccp",
 384                 .type           = CCP_SHA_TYPE_224,
 385                 .digest_size    = SHA224_DIGEST_SIZE,
 386                 .block_size     = SHA224_BLOCK_SIZE,
 387         },
 388         {
 389                 .version        = CCP_VERSION(3, 0),
 390                 .name           = "sha256",
 391                 .drv_name       = "sha256-ccp",
 392                 .type           = CCP_SHA_TYPE_256,
 393                 .digest_size    = SHA256_DIGEST_SIZE,
 394                 .block_size     = SHA256_BLOCK_SIZE,
 395         },
 396 };
 397
 398 static int ccp_register_hmac_alg(struct list_head *head,
 399                                  const struct ccp_sha_def *def,
 400                                  const struct ccp_crypto_ahash_alg *base_alg)
 401 {
 402         struct ccp_crypto_ahash_alg *ccp_alg;
 403         struct ahash_alg *alg;
 404         struct hash_alg_common *halg;
 405         struct crypto_alg *base;
 406         int ret;
 407
 408         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 409         if (!ccp_alg)
 410                 return -ENOMEM;
 411
 412         /* Copy the base algorithm and only change what's necessary */
 413         *ccp_alg = *base_alg;
 414         INIT_LIST_HEAD(&ccp_alg->entry);
 415
 416         strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME);
 417
 418         alg = &ccp_alg->alg;
 419         alg->setkey = ccp_sha_setkey;
 420
 421         halg = &alg->halg;
 422
 423         base = &halg->base;
 424         snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name);
 425         snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s",
 426                  def->drv_name);
 427         base->cra_init = ccp_hmac_sha_cra_init;
 428         base->cra_exit = ccp_hmac_sha_cra_exit;
 429
 430         ret = crypto_register_ahash(alg);
 431         if (ret) {
 432                 pr_err("%s ahash algorithm registration error (%d)\n",
 433                        base->cra_name, ret);
 434                 kfree(ccp_alg);
 435                 return ret;
 436         }
 437
 438         list_add(&ccp_alg->entry, head);
 439
 440         return ret;
 441 }
 442
 443 static int ccp_register_sha_alg(struct list_head *head,
 444                                 const struct ccp_sha_def *def)
 445 {
 446         struct ccp_crypto_ahash_alg *ccp_alg;
 447         struct ahash_alg *alg;
 448         struct hash_alg_common *halg;
 449         struct crypto_alg *base;
 450         int ret;
 451
 452         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 453         if (!ccp_alg)
 454                 return -ENOMEM;
 455
 456         INIT_LIST_HEAD(&ccp_alg->entry);
 457
 458         ccp_alg->type = def->type;
 459
 460         alg = &ccp_alg->alg;
 461         alg->init = ccp_sha_init;
 462         alg->update = ccp_sha_update;
 463         alg->final = ccp_sha_final;
 464         alg->finup = ccp_sha_finup;
 465         alg->digest = ccp_sha_digest;
 466         alg->export = ccp_sha_export;
 467         alg->import = ccp_sha_import;
 468
 469         halg = &alg->halg;
 470         halg->digestsize = def->digest_size;
 471         halg->statesize = sizeof(struct ccp_sha_exp_ctx);
 472
 473         base = &halg->base;
 474         snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 475         snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 476                  def->drv_name);
 477         base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC |
 478                           CRYPTO_ALG_KERN_DRIVER_ONLY |
 479                           CRYPTO_ALG_NEED_FALLBACK;
 480         base->cra_blocksize = def->block_size;
 481         base->cra_ctxsize = sizeof(struct ccp_ctx);
 482         base->cra_priority = CCP_CRA_PRIORITY;
 483         base->cra_type = &crypto_ahash_type;
 484         base->cra_init = ccp_sha_cra_init;
 485         base->cra_exit = ccp_sha_cra_exit;
 486         base->cra_module = THIS_MODULE;
 487
 488         ret = crypto_register_ahash(alg);
 489         if (ret) {
 490                 pr_err("%s ahash algorithm registration error (%d)\n",
 491                        base->cra_name, ret);
 492                 kfree(ccp_alg);
 493                 return ret;
 494         }
 495
 496         list_add(&ccp_alg->entry, head);
 497
 498         ret = ccp_register_hmac_alg(head, def, ccp_alg);
 499
 500         return ret;
 501 }
 502
 503 int ccp_register_sha_algs(struct list_head *head)
 504 {
 505         int i, ret;
 506         unsigned int ccpversion = ccp_version();
 507
 508         for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
 509                 if (sha_algs[i].version > ccpversion)
 510                         continue;
 511                 ret = ccp_register_sha_alg(head, &sha_algs[i]);
 512                 if (ret)
 513                         return ret;
 514         }
 515
 516         return 0;
 517 }