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 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src); 111 sg_mark_end(sg); 112 113 sg = rctx->data_sg.sgl; 114 } else if (rctx->buf_count) { 115 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); 116 117 sg = &rctx->buf_sg; 118 } else if (nbytes) { 119 sg = req->src; 120 } 121 122 rctx->msg_bits += (rctx->hash_cnt << 3); /* Total in bits */ 123 124 memset(&rctx->cmd, 0, sizeof(rctx->cmd)); 125 INIT_LIST_HEAD(&rctx->cmd.entry); 126 rctx->cmd.engine = CCP_ENGINE_SHA; 127 rctx->cmd.u.sha.type = rctx->type; 128 rctx->cmd.u.sha.ctx = &rctx->ctx_sg; 129 rctx->cmd.u.sha.ctx_len = sizeof(rctx->ctx); 130 rctx->cmd.u.sha.src = sg; 131 rctx->cmd.u.sha.src_len = rctx->hash_cnt; 132 rctx->cmd.u.sha.opad = ctx->u.sha.key_len ? 133 &ctx->u.sha.opad_sg : NULL; 134 rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ? 135 ctx->u.sha.opad_count : 0; 136 rctx->cmd.u.sha.first = rctx->first; 137 rctx->cmd.u.sha.final = rctx->final; 138 rctx->cmd.u.sha.msg_bits = rctx->msg_bits; 139 140 rctx->first = 0; 141 142 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd); 143 144 return ret; 145} 146 147static int ccp_sha_init(struct ahash_request *req) 148{ 149 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 150 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); 151 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 152 struct ccp_crypto_ahash_alg *alg = 153 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm)); 154 unsigned int block_size = 155 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 156 157 memset(rctx, 0, sizeof(*rctx)); 158 159 rctx->type = alg->type; 160 rctx->first = 1; 161 162 if (ctx->u.sha.key_len) { 163 /* Buffer the HMAC key for first update */ 164 memcpy(rctx->buf, ctx->u.sha.ipad, block_size); 165 rctx->buf_count = block_size; 166 } 167 168 return 0; 169} 170 171static int ccp_sha_update(struct ahash_request *req) 172{ 173 return ccp_do_sha_update(req, req->nbytes, 0); 174} 175 176static int ccp_sha_final(struct ahash_request *req) 177{ 178 return ccp_do_sha_update(req, 0, 1); 179} 180 181static int ccp_sha_finup(struct ahash_request *req) 182{ 183 return ccp_do_sha_update(req, req->nbytes, 1); 184} 185 186static int ccp_sha_digest(struct ahash_request *req) 187{ 188 int ret; 189 190 ret = ccp_sha_init(req); 191 if (ret) 192 return ret; 193 194 return ccp_sha_finup(req); 195} 196 197static int ccp_sha_export(struct ahash_request *req, void *out) 198{ 199 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 200 struct ccp_sha_exp_ctx state; 201 202 /* Don't let anything leak to 'out' */ 203 memset(&state, 0, sizeof(state)); 204 205 state.type = rctx->type; 206 state.msg_bits = rctx->msg_bits; 207 state.first = rctx->first; 208 memcpy(state.ctx, rctx->ctx, sizeof(state.ctx)); 209 state.buf_count = rctx->buf_count; 210 memcpy(state.buf, rctx->buf, sizeof(state.buf)); 211 212 /* 'out' may not be aligned so memcpy from local variable */ 213 memcpy(out, &state, sizeof(state)); 214 215 return 0; 216} 217 218static int ccp_sha_import(struct ahash_request *req, const void *in) 219{ 220 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 221 struct ccp_sha_exp_ctx state; 222 223 /* 'in' may not be aligned so memcpy to local variable */ 224 memcpy(&state, in, sizeof(state)); 225 226 memset(rctx, 0, sizeof(*rctx)); 227 rctx->type = state.type; 228 rctx->msg_bits = state.msg_bits; 229 rctx->first = state.first; 230 memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx)); 231 rctx->buf_count = state.buf_count; 232 memcpy(rctx->buf, state.buf, sizeof(rctx->buf)); 233 234 return 0; 235} 236 237static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key, 238 unsigned int key_len) 239{ 240 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm)); 241 struct crypto_shash *shash = ctx->u.sha.hmac_tfm; 242 243 SHASH_DESC_ON_STACK(sdesc, shash); 244 245 unsigned int block_size = crypto_shash_blocksize(shash); 246 unsigned int digest_size = crypto_shash_digestsize(shash); 247 int i, ret; 248 249 /* Set to zero until complete */ 250 ctx->u.sha.key_len = 0; 251 252 /* Clear key area to provide zero padding for keys smaller 253 * than the block size 254 */ 255 memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key)); 256 257 if (key_len > block_size) { 258 /* Must hash the input key */ 259 sdesc->tfm = shash; 260 sdesc->flags = crypto_ahash_get_flags(tfm) & 261 CRYPTO_TFM_REQ_MAY_SLEEP; 262 263 ret = crypto_shash_digest(sdesc, key, key_len, 264 ctx->u.sha.key); 265 if (ret) { 266 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); 267 return -EINVAL; 268 } 269 270 key_len = digest_size; 271 } else { 272 memcpy(ctx->u.sha.key, key, key_len); 273 } 274 275 for (i = 0; i < block_size; i++) { 276 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36; 277 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c; 278 } 279 280 sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size); 281 ctx->u.sha.opad_count = block_size; 282 283 ctx->u.sha.key_len = key_len; 284 285 return 0; 286} 287 288static int ccp_sha_cra_init(struct crypto_tfm *tfm) 289{ 290 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 291 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm); 292 293 ctx->complete = ccp_sha_complete; 294 ctx->u.sha.key_len = 0; 295 296 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx)); 297 298 return 0; 299} 300 301static void ccp_sha_cra_exit(struct crypto_tfm *tfm) 302{ 303} 304 305static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm) 306{ 307 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 308 struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm); 309 struct crypto_shash *hmac_tfm; 310 311 hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0); 312 if (IS_ERR(hmac_tfm)) { 313 pr_warn("could not load driver %s need for HMAC support\n", 314 alg->child_alg); 315 return PTR_ERR(hmac_tfm); 316 } 317 318 ctx->u.sha.hmac_tfm = hmac_tfm; 319 320 return ccp_sha_cra_init(tfm); 321} 322 323static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm) 324{ 325 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 326 327 if (ctx->u.sha.hmac_tfm) 328 crypto_free_shash(ctx->u.sha.hmac_tfm); 329 330 ccp_sha_cra_exit(tfm); 331} 332 333struct ccp_sha_def { 334 const char *name; 335 const char *drv_name; 336 enum ccp_sha_type type; 337 u32 digest_size; 338 u32 block_size; 339}; 340 341static struct ccp_sha_def sha_algs[] = { 342 { 343 .name = "sha1", 344 .drv_name = "sha1-ccp", 345 .type = CCP_SHA_TYPE_1, 346 .digest_size = SHA1_DIGEST_SIZE, 347 .block_size = SHA1_BLOCK_SIZE, 348 }, 349 { 350 .name = "sha224", 351 .drv_name = "sha224-ccp", 352 .type = CCP_SHA_TYPE_224, 353 .digest_size = SHA224_DIGEST_SIZE, 354 .block_size = SHA224_BLOCK_SIZE, 355 }, 356 { 357 .name = "sha256", 358 .drv_name = "sha256-ccp", 359 .type = CCP_SHA_TYPE_256, 360 .digest_size = SHA256_DIGEST_SIZE, 361 .block_size = SHA256_BLOCK_SIZE, 362 }, 363}; 364 365static int ccp_register_hmac_alg(struct list_head *head, 366 const struct ccp_sha_def *def, 367 const struct ccp_crypto_ahash_alg *base_alg) 368{ 369 struct ccp_crypto_ahash_alg *ccp_alg; 370 struct ahash_alg *alg; 371 struct hash_alg_common *halg; 372 struct crypto_alg *base; 373 int ret; 374 375 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 376 if (!ccp_alg) 377 return -ENOMEM; 378 379 /* Copy the base algorithm and only change what's necessary */ 380 *ccp_alg = *base_alg; 381 INIT_LIST_HEAD(&ccp_alg->entry); 382 383 strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME); 384 385 alg = &ccp_alg->alg; 386 alg->setkey = ccp_sha_setkey; 387 388 halg = &alg->halg; 389 390 base = &halg->base; 391 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name); 392 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s", 393 def->drv_name); 394 base->cra_init = ccp_hmac_sha_cra_init; 395 base->cra_exit = ccp_hmac_sha_cra_exit; 396 397 ret = crypto_register_ahash(alg); 398 if (ret) { 399 pr_err("%s ahash algorithm registration error (%d)\n", 400 base->cra_name, ret); 401 kfree(ccp_alg); 402 return ret; 403 } 404 405 list_add(&ccp_alg->entry, head); 406 407 return ret; 408} 409 410static int ccp_register_sha_alg(struct list_head *head, 411 const struct ccp_sha_def *def) 412{ 413 struct ccp_crypto_ahash_alg *ccp_alg; 414 struct ahash_alg *alg; 415 struct hash_alg_common *halg; 416 struct crypto_alg *base; 417 int ret; 418 419 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 420 if (!ccp_alg) 421 return -ENOMEM; 422 423 INIT_LIST_HEAD(&ccp_alg->entry); 424 425 ccp_alg->type = def->type; 426 427 alg = &ccp_alg->alg; 428 alg->init = ccp_sha_init; 429 alg->update = ccp_sha_update; 430 alg->final = ccp_sha_final; 431 alg->finup = ccp_sha_finup; 432 alg->digest = ccp_sha_digest; 433 alg->export = ccp_sha_export; 434 alg->import = ccp_sha_import; 435 436 halg = &alg->halg; 437 halg->digestsize = def->digest_size; 438 halg->statesize = sizeof(struct ccp_sha_exp_ctx); 439 440 base = &halg->base; 441 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name); 442 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s", 443 def->drv_name); 444 base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC | 445 CRYPTO_ALG_KERN_DRIVER_ONLY | 446 CRYPTO_ALG_NEED_FALLBACK; 447 base->cra_blocksize = def->block_size; 448 base->cra_ctxsize = sizeof(struct ccp_ctx); 449 base->cra_priority = CCP_CRA_PRIORITY; 450 base->cra_type = &crypto_ahash_type; 451 base->cra_init = ccp_sha_cra_init; 452 base->cra_exit = ccp_sha_cra_exit; 453 base->cra_module = THIS_MODULE; 454 455 ret = crypto_register_ahash(alg); 456 if (ret) { 457 pr_err("%s ahash algorithm registration error (%d)\n", 458 base->cra_name, ret); 459 kfree(ccp_alg); 460 return ret; 461 } 462 463 list_add(&ccp_alg->entry, head); 464 465 ret = ccp_register_hmac_alg(head, def, ccp_alg); 466 467 return ret; 468} 469 470int ccp_register_sha_algs(struct list_head *head) 471{ 472 int i, ret; 473 474 for (i = 0; i < ARRAY_SIZE(sha_algs); i++) { 475 ret = ccp_register_sha_alg(head, &sha_algs[i]); 476 if (ret) 477 return ret; 478 } 479 480 return 0; 481} 482