linux/drivers/crypto/ccp/ccp-crypto-sha.c
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   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
  28static 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)
  51                memcpy(req->result, rctx->ctx, digest_size);
  52
  53e_free:
  54        sg_free_table(&rctx->data_sg);
  55
  56        return ret;
  57}
  58
  59static 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
 177e_free:
 178        sg_free_table(&rctx->data_sg);
 179
 180        return ret;
 181}
 182
 183static 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
 207static int ccp_sha_update(struct ahash_request *req)
 208{
 209        return ccp_do_sha_update(req, req->nbytes, 0);
 210}
 211
 212static int ccp_sha_final(struct ahash_request *req)
 213{
 214        return ccp_do_sha_update(req, 0, 1);
 215}
 216
 217static int ccp_sha_finup(struct ahash_request *req)
 218{
 219        return ccp_do_sha_update(req, req->nbytes, 1);
 220}
 221
 222static 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
 233static 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
 254static 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
 273static 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
 324static 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
 337static void ccp_sha_cra_exit(struct crypto_tfm *tfm)
 338{
 339}
 340
 341static 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
 359static 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
 369struct 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
 378static 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
 421static 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
 466static 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_TYPE_AHASH | 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_type = &crypto_ahash_type;
 507        base->cra_init = ccp_sha_cra_init;
 508        base->cra_exit = ccp_sha_cra_exit;
 509        base->cra_module = THIS_MODULE;
 510
 511        ret = crypto_register_ahash(alg);
 512        if (ret) {
 513                pr_err("%s ahash algorithm registration error (%d)\n",
 514                       base->cra_name, ret);
 515                kfree(ccp_alg);
 516                return ret;
 517        }
 518
 519        list_add(&ccp_alg->entry, head);
 520
 521        ret = ccp_register_hmac_alg(head, def, ccp_alg);
 522
 523        return ret;
 524}
 525
 526int ccp_register_sha_algs(struct list_head *head)
 527{
 528        int i, ret;
 529        unsigned int ccpversion = ccp_version();
 530
 531        for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
 532                if (sha_algs[i].version > ccpversion)
 533                        continue;
 534                ret = ccp_register_sha_alg(head, &sha_algs[i]);
 535                if (ret)
 536                        return ret;
 537        }
 538
 539        return 0;
 540}
 541