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 26 static 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 51 e_free: 52 sg_free_table(&rctx->data_sg); 53 54 return ret; 55 } 56 57 static 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; 153 154 e_free: 155 sg_free_table(&rctx->data_sg); 156 157 return ret; 158 } 159 160 static 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 } 183 184 static int ccp_sha_update(struct ahash_request *req) 185 { 186 return ccp_do_sha_update(req, req->nbytes, 0); 187 } 188 189 static int ccp_sha_final(struct ahash_request *req) 190 { 191 return ccp_do_sha_update(req, 0, 1); 192 } 193 194 static int ccp_sha_finup(struct ahash_request *req) 195 { 196 return ccp_do_sha_update(req, req->nbytes, 1); 197 } 198 199 static 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 } 209 210 static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key, 211 unsigned int key_len) 212 { 213 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm)); 214 struct crypto_shash *shash = ctx->u.sha.hmac_tfm; 215 216 SHASH_DESC_ON_STACK(sdesc, shash); 217 218 unsigned int block_size = crypto_shash_blocksize(shash); 219 unsigned int digest_size = crypto_shash_digestsize(shash); 220 int i, ret; 221 222 /* Set to zero until complete */ 223 ctx->u.sha.key_len = 0; 224 225 /* Clear key area to provide zero padding for keys smaller 226 * than the block size 227 */ 228 memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key)); 229 230 if (key_len > block_size) { 231 /* Must hash the input key */ 232 sdesc->tfm = shash; 233 sdesc->flags = crypto_ahash_get_flags(tfm) & 234 CRYPTO_TFM_REQ_MAY_SLEEP; 235 236 ret = crypto_shash_digest(sdesc, key, key_len, 237 ctx->u.sha.key); 238 if (ret) { 239 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); 240 return -EINVAL; 241 } 242 243 key_len = digest_size; 244 } else { 245 memcpy(ctx->u.sha.key, key, key_len); 246 } 247 248 for (i = 0; i < block_size; i++) { 249 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36; 250 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c; 251 } 252 253 sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size); 254 ctx->u.sha.opad_count = block_size; 255 256 ctx->u.sha.key_len = key_len; 257 258 return 0; 259 } 260 261 static int ccp_sha_cra_init(struct crypto_tfm *tfm) 262 { 263 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 264 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm); 265 266 ctx->complete = ccp_sha_complete; 267 ctx->u.sha.key_len = 0; 268 269 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx)); 270 271 return 0; 272 } 273 274 static void ccp_sha_cra_exit(struct crypto_tfm *tfm) 275 { 276 } 277 278 static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm) 279 { 280 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 281 struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm); 282 struct crypto_shash *hmac_tfm; 283 284 hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0); 285 if (IS_ERR(hmac_tfm)) { 286 pr_warn("could not load driver %s need for HMAC support\n", 287 alg->child_alg); 288 return PTR_ERR(hmac_tfm); 289 } 290 291 ctx->u.sha.hmac_tfm = hmac_tfm; 292 293 return ccp_sha_cra_init(tfm); 294 } 295 296 static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm) 297 { 298 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 299 300 if (ctx->u.sha.hmac_tfm) 301 crypto_free_shash(ctx->u.sha.hmac_tfm); 302 303 ccp_sha_cra_exit(tfm); 304 } 305 306 struct ccp_sha_def { 307 const char *name; 308 const char *drv_name; 309 enum ccp_sha_type type; 310 u32 digest_size; 311 u32 block_size; 312 }; 313 314 static struct ccp_sha_def sha_algs[] = { 315 { 316 .name = "sha1", 317 .drv_name = "sha1-ccp", 318 .type = CCP_SHA_TYPE_1, 319 .digest_size = SHA1_DIGEST_SIZE, 320 .block_size = SHA1_BLOCK_SIZE, 321 }, 322 { 323 .name = "sha224", 324 .drv_name = "sha224-ccp", 325 .type = CCP_SHA_TYPE_224, 326 .digest_size = SHA224_DIGEST_SIZE, 327 .block_size = SHA224_BLOCK_SIZE, 328 }, 329 { 330 .name = "sha256", 331 .drv_name = "sha256-ccp", 332 .type = CCP_SHA_TYPE_256, 333 .digest_size = SHA256_DIGEST_SIZE, 334 .block_size = SHA256_BLOCK_SIZE, 335 }, 336 }; 337 338 static int ccp_register_hmac_alg(struct list_head *head, 339 const struct ccp_sha_def *def, 340 const struct ccp_crypto_ahash_alg *base_alg) 341 { 342 struct ccp_crypto_ahash_alg *ccp_alg; 343 struct ahash_alg *alg; 344 struct hash_alg_common *halg; 345 struct crypto_alg *base; 346 int ret; 347 348 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 349 if (!ccp_alg) 350 return -ENOMEM; 351 352 /* Copy the base algorithm and only change what's necessary */ 353 *ccp_alg = *base_alg; 354 INIT_LIST_HEAD(&ccp_alg->entry); 355 356 strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME); 357 358 alg = &ccp_alg->alg; 359 alg->setkey = ccp_sha_setkey; 360 361 halg = &alg->halg; 362 363 base = &halg->base; 364 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name); 365 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s", 366 def->drv_name); 367 base->cra_init = ccp_hmac_sha_cra_init; 368 base->cra_exit = ccp_hmac_sha_cra_exit; 369 370 ret = crypto_register_ahash(alg); 371 if (ret) { 372 pr_err("%s ahash algorithm registration error (%d)\n", 373 base->cra_name, ret); 374 kfree(ccp_alg); 375 return ret; 376 } 377 378 list_add(&ccp_alg->entry, head); 379 380 return ret; 381 } 382 383 static int ccp_register_sha_alg(struct list_head *head, 384 const struct ccp_sha_def *def) 385 { 386 struct ccp_crypto_ahash_alg *ccp_alg; 387 struct ahash_alg *alg; 388 struct hash_alg_common *halg; 389 struct crypto_alg *base; 390 int ret; 391 392 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 393 if (!ccp_alg) 394 return -ENOMEM; 395 396 INIT_LIST_HEAD(&ccp_alg->entry); 397 398 ccp_alg->type = def->type; 399 400 alg = &ccp_alg->alg; 401 alg->init = ccp_sha_init; 402 alg->update = ccp_sha_update; 403 alg->final = ccp_sha_final; 404 alg->finup = ccp_sha_finup; 405 alg->digest = ccp_sha_digest; 406 407 halg = &alg->halg; 408 halg->digestsize = def->digest_size; 409 410 base = &halg->base; 411 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name); 412 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s", 413 def->drv_name); 414 base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC | 415 CRYPTO_ALG_KERN_DRIVER_ONLY | 416 CRYPTO_ALG_NEED_FALLBACK; 417 base->cra_blocksize = def->block_size; 418 base->cra_ctxsize = sizeof(struct ccp_ctx); 419 base->cra_priority = CCP_CRA_PRIORITY; 420 base->cra_type = &crypto_ahash_type; 421 base->cra_init = ccp_sha_cra_init; 422 base->cra_exit = ccp_sha_cra_exit; 423 base->cra_module = THIS_MODULE; 424 425 ret = crypto_register_ahash(alg); 426 if (ret) { 427 pr_err("%s ahash algorithm registration error (%d)\n", 428 base->cra_name, ret); 429 kfree(ccp_alg); 430 return ret; 431 } 432 433 list_add(&ccp_alg->entry, head); 434 435 ret = ccp_register_hmac_alg(head, def, ccp_alg); 436 437 return ret; 438 } 439 440 int ccp_register_sha_algs(struct list_head *head) 441 { 442 int i, ret; 443 444 for (i = 0; i < ARRAY_SIZE(sha_algs); i++) { 445 ret = ccp_register_sha_alg(head, &sha_algs[i]); 446 if (ret) 447 return ret; 448 } 449 450 return 0; 451 } 452