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 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 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 /* Update result area if supplied */ 47 if (req->result) 48 memcpy(req->result, rctx->ctx, digest_size); 49 50 e_free: 51 sg_free_table(&rctx->data_sg); 52 53 return ret; 54 } 55 56 static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes, 57 unsigned int final) 58 { 59 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 60 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); 61 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 62 struct scatterlist *sg; 63 unsigned int block_size = 64 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 65 unsigned int sg_count; 66 gfp_t gfp; 67 u64 len; 68 int ret; 69 70 len = (u64)rctx->buf_count + (u64)nbytes; 71 72 if (!final && (len <= block_size)) { 73 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src, 74 0, nbytes, 0); 75 rctx->buf_count += nbytes; 76 77 return 0; 78 } 79 80 rctx->src = req->src; 81 rctx->nbytes = nbytes; 82 83 rctx->final = final; 84 rctx->hash_rem = final ? 0 : len & (block_size - 1); 85 rctx->hash_cnt = len - rctx->hash_rem; 86 if (!final && !rctx->hash_rem) { 87 /* CCP can't do zero length final, so keep some data around */ 88 rctx->hash_cnt -= block_size; 89 rctx->hash_rem = block_size; 90 } 91 92 /* Initialize the context scatterlist */ 93 sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx)); 94 95 sg = NULL; 96 if (rctx->buf_count && nbytes) { 97 /* Build the data scatterlist table - allocate enough entries 98 * for both data pieces (buffer and input data) 99 */ 100 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? 101 GFP_KERNEL : GFP_ATOMIC; 102 sg_count = sg_nents(req->src) + 1; 103 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp); 104 if (ret) 105 return ret; 106 107 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); 108 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg); 109 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src); 110 sg_mark_end(sg); 111 112 sg = rctx->data_sg.sgl; 113 } else if (rctx->buf_count) { 114 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count); 115 116 sg = &rctx->buf_sg; 117 } else if (nbytes) { 118 sg = req->src; 119 } 120 121 rctx->msg_bits += (rctx->hash_cnt << 3); /* Total in bits */ 122 123 memset(&rctx->cmd, 0, sizeof(rctx->cmd)); 124 INIT_LIST_HEAD(&rctx->cmd.entry); 125 rctx->cmd.engine = CCP_ENGINE_SHA; 126 rctx->cmd.u.sha.type = rctx->type; 127 rctx->cmd.u.sha.ctx = &rctx->ctx_sg; 128 rctx->cmd.u.sha.ctx_len = sizeof(rctx->ctx); 129 rctx->cmd.u.sha.src = sg; 130 rctx->cmd.u.sha.src_len = rctx->hash_cnt; 131 rctx->cmd.u.sha.opad = ctx->u.sha.key_len ? 132 &ctx->u.sha.opad_sg : NULL; 133 rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ? 134 ctx->u.sha.opad_count : 0; 135 rctx->cmd.u.sha.first = rctx->first; 136 rctx->cmd.u.sha.final = rctx->final; 137 rctx->cmd.u.sha.msg_bits = rctx->msg_bits; 138 139 rctx->first = 0; 140 141 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd); 142 143 return ret; 144 } 145 146 static int ccp_sha_init(struct ahash_request *req) 147 { 148 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 149 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm); 150 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req); 151 struct ccp_crypto_ahash_alg *alg = 152 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm)); 153 unsigned int block_size = 154 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 155 156 memset(rctx, 0, sizeof(*rctx)); 157 158 rctx->type = alg->type; 159 rctx->first = 1; 160 161 if (ctx->u.sha.key_len) { 162 /* Buffer the HMAC key for first update */ 163 memcpy(rctx->buf, ctx->u.sha.ipad, block_size); 164 rctx->buf_count = block_size; 165 } 166 167 return 0; 168 } 169 170 static int ccp_sha_update(struct ahash_request *req) 171 { 172 return ccp_do_sha_update(req, req->nbytes, 0); 173 } 174 175 static int ccp_sha_final(struct ahash_request *req) 176 { 177 return ccp_do_sha_update(req, 0, 1); 178 } 179 180 static int ccp_sha_finup(struct ahash_request *req) 181 { 182 return ccp_do_sha_update(req, req->nbytes, 1); 183 } 184 185 static int ccp_sha_digest(struct ahash_request *req) 186 { 187 int ret; 188 189 ret = ccp_sha_init(req); 190 if (ret) 191 return ret; 192 193 return ccp_sha_finup(req); 194 } 195 196 static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key, 197 unsigned int key_len) 198 { 199 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm)); 200 struct crypto_shash *shash = ctx->u.sha.hmac_tfm; 201 struct { 202 struct shash_desc sdesc; 203 char ctx[crypto_shash_descsize(shash)]; 204 } desc; 205 unsigned int block_size = crypto_shash_blocksize(shash); 206 unsigned int digest_size = crypto_shash_digestsize(shash); 207 int i, ret; 208 209 /* Set to zero until complete */ 210 ctx->u.sha.key_len = 0; 211 212 /* Clear key area to provide zero padding for keys smaller 213 * than the block size 214 */ 215 memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key)); 216 217 if (key_len > block_size) { 218 /* Must hash the input key */ 219 desc.sdesc.tfm = shash; 220 desc.sdesc.flags = crypto_ahash_get_flags(tfm) & 221 CRYPTO_TFM_REQ_MAY_SLEEP; 222 223 ret = crypto_shash_digest(&desc.sdesc, key, key_len, 224 ctx->u.sha.key); 225 if (ret) { 226 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); 227 return -EINVAL; 228 } 229 230 key_len = digest_size; 231 } else 232 memcpy(ctx->u.sha.key, key, key_len); 233 234 for (i = 0; i < block_size; i++) { 235 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36; 236 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c; 237 } 238 239 sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size); 240 ctx->u.sha.opad_count = block_size; 241 242 ctx->u.sha.key_len = key_len; 243 244 return 0; 245 } 246 247 static int ccp_sha_cra_init(struct crypto_tfm *tfm) 248 { 249 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 250 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm); 251 252 ctx->complete = ccp_sha_complete; 253 ctx->u.sha.key_len = 0; 254 255 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx)); 256 257 return 0; 258 } 259 260 static void ccp_sha_cra_exit(struct crypto_tfm *tfm) 261 { 262 } 263 264 static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm) 265 { 266 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 267 struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm); 268 struct crypto_shash *hmac_tfm; 269 270 hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0); 271 if (IS_ERR(hmac_tfm)) { 272 pr_warn("could not load driver %s need for HMAC support\n", 273 alg->child_alg); 274 return PTR_ERR(hmac_tfm); 275 } 276 277 ctx->u.sha.hmac_tfm = hmac_tfm; 278 279 return ccp_sha_cra_init(tfm); 280 } 281 282 static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm) 283 { 284 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm); 285 286 if (ctx->u.sha.hmac_tfm) 287 crypto_free_shash(ctx->u.sha.hmac_tfm); 288 289 ccp_sha_cra_exit(tfm); 290 } 291 292 struct ccp_sha_def { 293 const char *name; 294 const char *drv_name; 295 enum ccp_sha_type type; 296 u32 digest_size; 297 u32 block_size; 298 }; 299 300 static struct ccp_sha_def sha_algs[] = { 301 { 302 .name = "sha1", 303 .drv_name = "sha1-ccp", 304 .type = CCP_SHA_TYPE_1, 305 .digest_size = SHA1_DIGEST_SIZE, 306 .block_size = SHA1_BLOCK_SIZE, 307 }, 308 { 309 .name = "sha224", 310 .drv_name = "sha224-ccp", 311 .type = CCP_SHA_TYPE_224, 312 .digest_size = SHA224_DIGEST_SIZE, 313 .block_size = SHA224_BLOCK_SIZE, 314 }, 315 { 316 .name = "sha256", 317 .drv_name = "sha256-ccp", 318 .type = CCP_SHA_TYPE_256, 319 .digest_size = SHA256_DIGEST_SIZE, 320 .block_size = SHA256_BLOCK_SIZE, 321 }, 322 }; 323 324 static int ccp_register_hmac_alg(struct list_head *head, 325 const struct ccp_sha_def *def, 326 const struct ccp_crypto_ahash_alg *base_alg) 327 { 328 struct ccp_crypto_ahash_alg *ccp_alg; 329 struct ahash_alg *alg; 330 struct hash_alg_common *halg; 331 struct crypto_alg *base; 332 int ret; 333 334 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 335 if (!ccp_alg) 336 return -ENOMEM; 337 338 /* Copy the base algorithm and only change what's necessary */ 339 *ccp_alg = *base_alg; 340 INIT_LIST_HEAD(&ccp_alg->entry); 341 342 strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME); 343 344 alg = &ccp_alg->alg; 345 alg->setkey = ccp_sha_setkey; 346 347 halg = &alg->halg; 348 349 base = &halg->base; 350 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name); 351 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s", 352 def->drv_name); 353 base->cra_init = ccp_hmac_sha_cra_init; 354 base->cra_exit = ccp_hmac_sha_cra_exit; 355 356 ret = crypto_register_ahash(alg); 357 if (ret) { 358 pr_err("%s ahash algorithm registration error (%d)\n", 359 base->cra_name, ret); 360 kfree(ccp_alg); 361 return ret; 362 } 363 364 list_add(&ccp_alg->entry, head); 365 366 return ret; 367 } 368 369 static int ccp_register_sha_alg(struct list_head *head, 370 const struct ccp_sha_def *def) 371 { 372 struct ccp_crypto_ahash_alg *ccp_alg; 373 struct ahash_alg *alg; 374 struct hash_alg_common *halg; 375 struct crypto_alg *base; 376 int ret; 377 378 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL); 379 if (!ccp_alg) 380 return -ENOMEM; 381 382 INIT_LIST_HEAD(&ccp_alg->entry); 383 384 ccp_alg->type = def->type; 385 386 alg = &ccp_alg->alg; 387 alg->init = ccp_sha_init; 388 alg->update = ccp_sha_update; 389 alg->final = ccp_sha_final; 390 alg->finup = ccp_sha_finup; 391 alg->digest = ccp_sha_digest; 392 393 halg = &alg->halg; 394 halg->digestsize = def->digest_size; 395 396 base = &halg->base; 397 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name); 398 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s", 399 def->drv_name); 400 base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC | 401 CRYPTO_ALG_KERN_DRIVER_ONLY | 402 CRYPTO_ALG_NEED_FALLBACK; 403 base->cra_blocksize = def->block_size; 404 base->cra_ctxsize = sizeof(struct ccp_ctx); 405 base->cra_priority = CCP_CRA_PRIORITY; 406 base->cra_type = &crypto_ahash_type; 407 base->cra_init = ccp_sha_cra_init; 408 base->cra_exit = ccp_sha_cra_exit; 409 base->cra_module = THIS_MODULE; 410 411 ret = crypto_register_ahash(alg); 412 if (ret) { 413 pr_err("%s ahash algorithm registration error (%d)\n", 414 base->cra_name, ret); 415 kfree(ccp_alg); 416 return ret; 417 } 418 419 list_add(&ccp_alg->entry, head); 420 421 ret = ccp_register_hmac_alg(head, def, ccp_alg); 422 423 return ret; 424 } 425 426 int ccp_register_sha_algs(struct list_head *head) 427 { 428 int i, ret; 429 430 for (i = 0; i < ARRAY_SIZE(sha_algs); i++) { 431 ret = ccp_register_sha_alg(head, &sha_algs[i]); 432 if (ret) 433 return ret; 434 } 435 436 return 0; 437 } 438