1/* 2 * AMD Cryptographic Coprocessor (CCP) SHA crypto API support 3 * 4 * Copyright (C) 2013 Advanced Micro Devices, Inc. 5 * 6 * Author: Tom Lendacky <thomas.lendacky@amd.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13#include <linux/module.h> 14#include <linux/sched.h> 15#include <linux/delay.h> 16#include <linux/scatterlist.h> 17#include <linux/crypto.h> 18#include <crypto/algapi.h> 19#include <crypto/hash.h> 20#include <crypto/internal/hash.h> 21#include <crypto/sha.h> 22#include <crypto/scatterwalk.h> 23 24#include "ccp-crypto.h" 25 26static int ccp_sha_complete(struct crypto_async_request *async_req, int ret) 27{ 28 struct ahash_request *req = ahash_request_cast(async_req); 29 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 30 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 31 unsigned int digest_size = crypto_ahash_digestsize(tfm); 32 33 if (ret) 34 goto e_free; 35 36 if (rctx->hash_rem) { 37 /* Save remaining data to buffer */ 38 unsigned int offset = rctx->nbytes - rctx->hash_rem; 39 40 scatterwalk_map_and_copy(rctx->buf, rctx->src, 41 offset, rctx->hash_rem, 0); 42 rctx->buf_count = rctx->hash_rem; 43 } else { 44 rctx->buf_count = 0; 45 } 46 47 /* Update result area if supplied */ 48 if (req->result) 49 memcpy(req->result, rctx->ctx, digest_size); 50 51e_free: 52 sg_free_table(&rctx->data_sg); 53 54 return ret; 55} 56 57static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes, 58 unsigned int final) 59{ 60 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 61 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); 62 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 63 struct scatterlist *sg; 64 unsigned int block_size = 65 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 66 unsigned int sg_count; 67 gfp_t gfp; 68 u64 len; 69 int ret; 70 71 len = (u64)rctx->buf_count + (u64)nbytes; 72 73 if (!final && (len <= block_size)) { 74 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src, 75 0, nbytes, 0); 76 rctx->buf_count += nbytes; 77 78 return 0; 79 } 80 81 rctx->src = req->src; 82 rctx->nbytes = nbytes; 83 84 rctx->final = final; 85 rctx->hash_rem = final ? 0 : len & (block_size - 1); 86 rctx->hash_cnt = len - rctx->hash_rem; 87 if (!final && !rctx->hash_rem) { 88 /* CCP can't do zero length final, so keep some data around */ 89 rctx->hash_cnt -= block_size; 90 rctx->hash_rem = block_size; 91 } 92 93 /* Initialize the context scatterlist */ 94 sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx)); 95 96 sg = NULL; 97 if (rctx->buf_count && nbytes) { 98 /* Build the data scatterlist table - allocate enough entries 99 * for both data pieces (buffer and input data) 100 */ 101 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? 102 GFP_KERNEL : GFP_ATOMIC; 103 sg_count = sg_nents(req->src) + 1; 104 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp); 105 if (ret) 106 return ret; 107 108 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); 109 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg); 110 if (!sg) { 111 ret = -EINVAL; 112 goto e_free; 113 } 114 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src); 115 if (!sg) { 116 ret = -EINVAL; 117 goto e_free; 118 } 119 sg_mark_end(sg); 120 121 sg = rctx->data_sg.sgl; 122 } else if (rctx->buf_count) { 123 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); 124 125 sg = &rctx->buf_sg; 126 } else if (nbytes) { 127 sg = req->src; 128 } 129 130 rctx->msg_bits += (rctx->hash_cnt << 3); /* Total in bits */ 131 132 memset(&rctx->cmd, 0, sizeof(rctx->cmd)); 133 INIT_LIST_HEAD(&rctx->cmd.entry); 134 rctx->cmd.engine = CCP_ENGINE_SHA; 135 rctx->cmd.u.sha.type = rctx->type; 136 rctx->cmd.u.sha.ctx = &rctx->ctx_sg; 137 rctx->cmd.u.sha.ctx_len = sizeof(rctx->ctx); 138 rctx->cmd.u.sha.src = sg; 139 rctx->cmd.u.sha.src_len = rctx->hash_cnt; 140 rctx->cmd.u.sha.opad = ctx->u.sha.key_len ? 141 &ctx->u.sha.opad_sg : NULL; 142 rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ? 143 ctx->u.sha.opad_count : 0; 144 rctx->cmd.u.sha.first = rctx->first; 145 rctx->cmd.u.sha.final = rctx->final; 146 rctx->cmd.u.sha.msg_bits = rctx->msg_bits; 147 148 rctx->first = 0; 149 150 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd); 151 152 return ret; 153 154e_free: 155 sg_free_table(&rctx->data_sg); 156 157 return ret; 158} 159 160static int ccp_sha_init(struct ahash_request *req) 161{ 162 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 163 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); 164 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 165 struct ccp_crypto_ahash_alg *alg = 166 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm)); 167 unsigned int block_size = 168 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 169 170 memset(rctx, 0, sizeof(*rctx)); 171 172 rctx->type = alg->type; 173 rctx->first = 1; 174 175 if (ctx->u.sha.key_len) { 176 /* Buffer the HMAC key for first update */ 177 memcpy(rctx->buf, ctx->u.sha.ipad, block_size); 178 rctx->buf_count = block_size; 179 } 180 181 return 0; 182} 183 184static int ccp_sha_update(struct ahash_request *req) 185{ 186 return ccp_do_sha_update(req, req->nbytes, 0); 187} 188 189static int ccp_sha_final(struct ahash_request *req) 190{ 191 return ccp_do_sha_update(req, 0, 1); 192} 193 194static int ccp_sha_finup(struct ahash_request *req) 195{ 196 return ccp_do_sha_update(req, req->nbytes, 1); 197} 198 199static int ccp_sha_digest(struct ahash_request *req) 200{ 201 int ret; 202 203 ret = ccp_sha_init(req); 204 if (ret) 205 return ret; 206 207 return ccp_sha_finup(req); 208} 209 210static int ccp_sha_export(struct ahash_request *req, void *out) 211{ 212 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 213 struct ccp_sha_exp_ctx state; 214 215 /* Don't let anything leak to 'out' */ 216 memset(&state, 0, sizeof(state)); 217 218 state.type = rctx->type; 219 state.msg_bits = rctx->msg_bits; 220 state.first = rctx->first; 221 memcpy(state.ctx, rctx->ctx, sizeof(state.ctx)); 222 state.buf_count = rctx->buf_count; 223 memcpy(state.buf, rctx->buf, sizeof(state.buf)); 224 225 /* 'out' may not be aligned so memcpy from local variable */ 226 memcpy(out, &state, sizeof(state)); 227 228 return 0; 229} 230 231static int ccp_sha_import(struct ahash_request *req, const void *in) 232{ 233 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 234 struct ccp_sha_exp_ctx state; 235 236 /* 'in' may not be aligned so memcpy to local variable */ 237 memcpy(&state, in, sizeof(state)); 238 239 memset(rctx, 0, sizeof(*rctx)); 240 rctx->type = state.type; 241 rctx->msg_bits = state.msg_bits; 242 rctx->first = state.first; 243 memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx)); 244 rctx->buf_count = state.buf_count; 245 memcpy(rctx->buf, state.buf, sizeof(rctx->buf)); 246 247 return 0; 248} 249 250static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key, 251 unsigned int key_len) 252{ 253 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm)); 254 struct crypto_shash *shash = ctx->u.sha.hmac_tfm; 255 256 SHASH_DESC_ON_STACK(sdesc, shash); 257 258 unsigned int block_size = crypto_shash_blocksize(shash); 259 unsigned int digest_size = crypto_shash_digestsize(shash); 260 int i, ret; 261 262 /* Set to zero until complete */ 263 ctx->u.sha.key_len = 0; 264 265 /* Clear key area to provide zero padding for keys smaller 266 * than the block size 267 */ 268 memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key)); 269 270 if (key_len > block_size) { 271 /* Must hash the input key */ 272 sdesc->tfm = shash; 273 sdesc->flags = crypto_ahash_get_flags(tfm) & 274 CRYPTO_TFM_REQ_MAY_SLEEP; 275 276 ret = crypto_shash_digest(sdesc, key, key_len, 277 ctx->u.sha.key); 278 if (ret) { 279 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); 280 return -EINVAL; 281 } 282 283 key_len = digest_size; 284 } else { 285 memcpy(ctx->u.sha.key, key, key_len); 286 } 287 288 for (i = 0; i < block_size; i++) { 289 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36; 290 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c; 291 } 292 293 sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size); 294 ctx->u.sha.opad_count = block_size; 295 296 ctx->u.sha.key_len = key_len; 297 298 return 0; 299} 300 301static int ccp_sha_cra_init(struct crypto_tfm *tfm) 302{ 303 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 304 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm); 305 306 ctx->complete = ccp_sha_complete; 307 ctx->u.sha.key_len = 0; 308 309 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx)); 310 311 return 0; 312} 313 314static void ccp_sha_cra_exit(struct crypto_tfm *tfm) 315{ 316} 317 318static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm) 319{ 320 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 321 struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm); 322 struct crypto_shash *hmac_tfm; 323 324 hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0); 325 if (IS_ERR(hmac_tfm)) { 326 pr_warn("could not load driver %s need for HMAC support\n", 327 alg->child_alg); 328 return PTR_ERR(hmac_tfm); 329 } 330 331 ctx->u.sha.hmac_tfm = hmac_tfm; 332 333 return ccp_sha_cra_init(tfm); 334} 335 336static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm) 337{ 338 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 339 340 if (ctx->u.sha.hmac_tfm) 341 crypto_free_shash(ctx->u.sha.hmac_tfm); 342 343 ccp_sha_cra_exit(tfm); 344} 345 346struct ccp_sha_def { 347 const char *name; 348 const char *drv_name; 349 enum ccp_sha_type type; 350 u32 digest_size; 351 u32 block_size; 352}; 353 354static struct ccp_sha_def sha_algs[] = { 355 { 356 .name = "sha1", 357 .drv_name = "sha1-ccp", 358 .type = CCP_SHA_TYPE_1, 359 .digest_size = SHA1_DIGEST_SIZE, 360 .block_size = SHA1_BLOCK_SIZE, 361 }, 362 { 363 .name = "sha224", 364 .drv_name = "sha224-ccp", 365 .type = CCP_SHA_TYPE_224, 366 .digest_size = SHA224_DIGEST_SIZE, 367 .block_size = SHA224_BLOCK_SIZE, 368 }, 369 { 370 .name = "sha256", 371 .drv_name = "sha256-ccp", 372 .type = CCP_SHA_TYPE_256, 373 .digest_size = SHA256_DIGEST_SIZE, 374 .block_size = SHA256_BLOCK_SIZE, 375 }, 376}; 377 378static int ccp_register_hmac_alg(struct list_head *head, 379 const struct ccp_sha_def *def, 380 const struct ccp_crypto_ahash_alg *base_alg) 381{ 382 struct ccp_crypto_ahash_alg *ccp_alg; 383 struct ahash_alg *alg; 384 struct hash_alg_common *halg; 385 struct crypto_alg *base; 386 int ret; 387 388 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 389 if (!ccp_alg) 390 return -ENOMEM; 391 392 /* Copy the base algorithm and only change what's necessary */ 393 *ccp_alg = *base_alg; 394 INIT_LIST_HEAD(&ccp_alg->entry); 395 396 strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME); 397 398 alg = &ccp_alg->alg; 399 alg->setkey = ccp_sha_setkey; 400 401 halg = &alg->halg; 402 403 base = &halg->base; 404 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name); 405 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s", 406 def->drv_name); 407 base->cra_init = ccp_hmac_sha_cra_init; 408 base->cra_exit = ccp_hmac_sha_cra_exit; 409 410 ret = crypto_register_ahash(alg); 411 if (ret) { 412 pr_err("%s ahash algorithm registration error (%d)\n", 413 base->cra_name, ret); 414 kfree(ccp_alg); 415 return ret; 416 } 417 418 list_add(&ccp_alg->entry, head); 419 420 return ret; 421} 422 423static int ccp_register_sha_alg(struct list_head *head, 424 const struct ccp_sha_def *def) 425{ 426 struct ccp_crypto_ahash_alg *ccp_alg; 427 struct ahash_alg *alg; 428 struct hash_alg_common *halg; 429 struct crypto_alg *base; 430 int ret; 431 432 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 433 if (!ccp_alg) 434 return -ENOMEM; 435 436 INIT_LIST_HEAD(&ccp_alg->entry); 437 438 ccp_alg->type = def->type; 439 440 alg = &ccp_alg->alg; 441 alg->init = ccp_sha_init; 442 alg->update = ccp_sha_update; 443 alg->final = ccp_sha_final; 444 alg->finup = ccp_sha_finup; 445 alg->digest = ccp_sha_digest; 446 alg->export = ccp_sha_export; 447 alg->import = ccp_sha_import; 448 449 halg = &alg->halg; 450 halg->digestsize = def->digest_size; 451 halg->statesize = sizeof(struct ccp_sha_exp_ctx); 452 453 base = &halg->base; 454 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name); 455 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s", 456 def->drv_name); 457 base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC | 458 CRYPTO_ALG_KERN_DRIVER_ONLY | 459 CRYPTO_ALG_NEED_FALLBACK; 460 base->cra_blocksize = def->block_size; 461 base->cra_ctxsize = sizeof(struct ccp_ctx); 462 base->cra_priority = CCP_CRA_PRIORITY; 463 base->cra_type = &crypto_ahash_type; 464 base->cra_init = ccp_sha_cra_init; 465 base->cra_exit = ccp_sha_cra_exit; 466 base->cra_module = THIS_MODULE; 467 468 ret = crypto_register_ahash(alg); 469 if (ret) { 470 pr_err("%s ahash algorithm registration error (%d)\n", 471 base->cra_name, ret); 472 kfree(ccp_alg); 473 return ret; 474 } 475 476 list_add(&ccp_alg->entry, head); 477 478 ret = ccp_register_hmac_alg(head, def, ccp_alg); 479 480 return ret; 481} 482 483int ccp_register_sha_algs(struct list_head *head) 484{ 485 int i, ret; 486 487 for (i = 0; i < ARRAY_SIZE(sha_algs); i++) { 488 ret = ccp_register_sha_alg(head, &sha_algs[i]); 489 if (ret) 490 return ret; 491 } 492 493 return 0; 494} 495