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 } 518