1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Synchronous Cryptographic Hash operations. 4 * 5 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> 6 */ 7 8 #include <crypto/scatterwalk.h> 9 #include <linux/cryptouser.h> 10 #include <linux/err.h> 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/seq_file.h> 14 #include <linux/string.h> 15 #include <net/netlink.h> 16 17 #include "hash.h" 18 19 int shash_no_setkey(struct crypto_shash *tfm, const u8 *key, 20 unsigned int keylen) 21 { 22 return -ENOSYS; 23 } 24 EXPORT_SYMBOL_GPL(shash_no_setkey); 25 26 static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg) 27 { 28 if (crypto_shash_alg_needs_key(alg)) 29 crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY); 30 } 31 32 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 33 unsigned int keylen) 34 { 35 struct shash_alg *shash = crypto_shash_alg(tfm); 36 int err; 37 38 err = shash->setkey(tfm, key, keylen); 39 if (unlikely(err)) { 40 shash_set_needkey(tfm, shash); 41 return err; 42 } 43 44 crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); 45 return 0; 46 } 47 EXPORT_SYMBOL_GPL(crypto_shash_setkey); 48 49 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 50 unsigned int len) 51 { 52 return crypto_shash_alg(desc->tfm)->update(desc, data, len); 53 } 54 EXPORT_SYMBOL_GPL(crypto_shash_update); 55 56 int crypto_shash_final(struct shash_desc *desc, u8 *out) 57 { 58 return crypto_shash_alg(desc->tfm)->final(desc, out); 59 } 60 EXPORT_SYMBOL_GPL(crypto_shash_final); 61 62 static int shash_default_finup(struct shash_desc *desc, const u8 *data, 63 unsigned int len, u8 *out) 64 { 65 struct shash_alg *shash = crypto_shash_alg(desc->tfm); 66 67 return shash->update(desc, data, len) ?: 68 shash->final(desc, out); 69 } 70 71 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 72 unsigned int len, u8 *out) 73 { 74 return crypto_shash_alg(desc->tfm)->finup(desc, data, len, out); 75 } 76 EXPORT_SYMBOL_GPL(crypto_shash_finup); 77 78 static int shash_default_digest(struct shash_desc *desc, const u8 *data, 79 unsigned int len, u8 *out) 80 { 81 struct shash_alg *shash = crypto_shash_alg(desc->tfm); 82 83 return shash->init(desc) ?: 84 shash->finup(desc, data, len, out); 85 } 86 87 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 88 unsigned int len, u8 *out) 89 { 90 struct crypto_shash *tfm = desc->tfm; 91 92 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 93 return -ENOKEY; 94 95 return crypto_shash_alg(tfm)->digest(desc, data, len, out); 96 } 97 EXPORT_SYMBOL_GPL(crypto_shash_digest); 98 99 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data, 100 unsigned int len, u8 *out) 101 { 102 SHASH_DESC_ON_STACK(desc, tfm); 103 int err; 104 105 desc->tfm = tfm; 106 107 err = crypto_shash_digest(desc, data, len, out); 108 109 shash_desc_zero(desc); 110 111 return err; 112 } 113 EXPORT_SYMBOL_GPL(crypto_shash_tfm_digest); 114 115 int crypto_shash_export(struct shash_desc *desc, void *out) 116 { 117 struct crypto_shash *tfm = desc->tfm; 118 struct shash_alg *shash = crypto_shash_alg(tfm); 119 120 if (shash->export) 121 return shash->export(desc, out); 122 123 memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(tfm)); 124 return 0; 125 } 126 EXPORT_SYMBOL_GPL(crypto_shash_export); 127 128 int crypto_shash_import(struct shash_desc *desc, const void *in) 129 { 130 struct crypto_shash *tfm = desc->tfm; 131 struct shash_alg *shash = crypto_shash_alg(tfm); 132 133 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 134 return -ENOKEY; 135 136 if (shash->import) 137 return shash->import(desc, in); 138 139 memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(tfm)); 140 return 0; 141 } 142 EXPORT_SYMBOL_GPL(crypto_shash_import); 143 144 static void crypto_shash_exit_tfm(struct crypto_tfm *tfm) 145 { 146 struct crypto_shash *hash = __crypto_shash_cast(tfm); 147 struct shash_alg *alg = crypto_shash_alg(hash); 148 149 alg->exit_tfm(hash); 150 } 151 152 static int crypto_shash_init_tfm(struct crypto_tfm *tfm) 153 { 154 struct crypto_shash *hash = __crypto_shash_cast(tfm); 155 struct shash_alg *alg = crypto_shash_alg(hash); 156 int err; 157 158 hash->descsize = alg->descsize; 159 160 shash_set_needkey(hash, alg); 161 162 if (alg->exit_tfm) 163 tfm->exit = crypto_shash_exit_tfm; 164 165 if (!alg->init_tfm) 166 return 0; 167 168 err = alg->init_tfm(hash); 169 if (err) 170 return err; 171 172 /* ->init_tfm() may have increased the descsize. */ 173 if (WARN_ON_ONCE(hash->descsize > HASH_MAX_DESCSIZE)) { 174 if (alg->exit_tfm) 175 alg->exit_tfm(hash); 176 return -EINVAL; 177 } 178 179 return 0; 180 } 181 182 static void crypto_shash_free_instance(struct crypto_instance *inst) 183 { 184 struct shash_instance *shash = shash_instance(inst); 185 186 shash->free(shash); 187 } 188 189 static int __maybe_unused crypto_shash_report( 190 struct sk_buff *skb, struct crypto_alg *alg) 191 { 192 struct crypto_report_hash rhash; 193 struct shash_alg *salg = __crypto_shash_alg(alg); 194 195 memset(&rhash, 0, sizeof(rhash)); 196 197 strscpy(rhash.type, "shash", sizeof(rhash.type)); 198 199 rhash.blocksize = alg->cra_blocksize; 200 rhash.digestsize = salg->digestsize; 201 202 return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash); 203 } 204 205 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 206 __maybe_unused; 207 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) 208 { 209 struct shash_alg *salg = __crypto_shash_alg(alg); 210 211 seq_printf(m, "type : shash\n"); 212 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); 213 seq_printf(m, "digestsize : %u\n", salg->digestsize); 214 } 215 216 const struct crypto_type crypto_shash_type = { 217 .extsize = crypto_alg_extsize, 218 .init_tfm = crypto_shash_init_tfm, 219 .free = crypto_shash_free_instance, 220 #ifdef CONFIG_PROC_FS 221 .show = crypto_shash_show, 222 #endif 223 #if IS_ENABLED(CONFIG_CRYPTO_USER) 224 .report = crypto_shash_report, 225 #endif 226 .maskclear = ~CRYPTO_ALG_TYPE_MASK, 227 .maskset = CRYPTO_ALG_TYPE_MASK, 228 .type = CRYPTO_ALG_TYPE_SHASH, 229 .tfmsize = offsetof(struct crypto_shash, base), 230 }; 231 232 int crypto_grab_shash(struct crypto_shash_spawn *spawn, 233 struct crypto_instance *inst, 234 const char *name, u32 type, u32 mask) 235 { 236 spawn->base.frontend = &crypto_shash_type; 237 return crypto_grab_spawn(&spawn->base, inst, name, type, mask); 238 } 239 EXPORT_SYMBOL_GPL(crypto_grab_shash); 240 241 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 242 u32 mask) 243 { 244 return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask); 245 } 246 EXPORT_SYMBOL_GPL(crypto_alloc_shash); 247 248 int crypto_has_shash(const char *alg_name, u32 type, u32 mask) 249 { 250 return crypto_type_has_alg(alg_name, &crypto_shash_type, type, mask); 251 } 252 EXPORT_SYMBOL_GPL(crypto_has_shash); 253 254 struct crypto_shash *crypto_clone_shash(struct crypto_shash *hash) 255 { 256 struct crypto_tfm *tfm = crypto_shash_tfm(hash); 257 struct shash_alg *alg = crypto_shash_alg(hash); 258 struct crypto_shash *nhash; 259 int err; 260 261 if (!crypto_shash_alg_has_setkey(alg)) { 262 tfm = crypto_tfm_get(tfm); 263 if (IS_ERR(tfm)) 264 return ERR_CAST(tfm); 265 266 return hash; 267 } 268 269 if (!alg->clone_tfm && (alg->init_tfm || alg->base.cra_init)) 270 return ERR_PTR(-ENOSYS); 271 272 nhash = crypto_clone_tfm(&crypto_shash_type, tfm); 273 if (IS_ERR(nhash)) 274 return nhash; 275 276 nhash->descsize = hash->descsize; 277 278 if (alg->clone_tfm) { 279 err = alg->clone_tfm(nhash, hash); 280 if (err) { 281 crypto_free_shash(nhash); 282 return ERR_PTR(err); 283 } 284 } 285 286 return nhash; 287 } 288 EXPORT_SYMBOL_GPL(crypto_clone_shash); 289 290 int hash_prepare_alg(struct hash_alg_common *alg) 291 { 292 struct crypto_alg *base = &alg->base; 293 294 if (alg->digestsize > HASH_MAX_DIGESTSIZE) 295 return -EINVAL; 296 297 /* alignmask is not useful for hashes, so it is not supported. */ 298 if (base->cra_alignmask) 299 return -EINVAL; 300 301 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; 302 303 return 0; 304 } 305 306 static int shash_prepare_alg(struct shash_alg *alg) 307 { 308 struct crypto_alg *base = &alg->halg.base; 309 int err; 310 311 if (alg->descsize > HASH_MAX_DESCSIZE) 312 return -EINVAL; 313 314 if ((alg->export && !alg->import) || (alg->import && !alg->export)) 315 return -EINVAL; 316 317 err = hash_prepare_alg(&alg->halg); 318 if (err) 319 return err; 320 321 base->cra_type = &crypto_shash_type; 322 base->cra_flags |= CRYPTO_ALG_TYPE_SHASH; 323 324 /* 325 * Handle missing optional functions. For each one we can either 326 * install a default here, or we can leave the pointer as NULL and check 327 * the pointer for NULL in crypto_shash_*(), avoiding an indirect call 328 * when the default behavior is desired. For ->finup and ->digest we 329 * install defaults, since for optimal performance algorithms should 330 * implement these anyway. On the other hand, for ->import and 331 * ->export the common case and best performance comes from the simple 332 * memcpy of the shash_desc_ctx, so when those pointers are NULL we 333 * leave them NULL and provide the memcpy with no indirect call. 334 */ 335 if (!alg->finup) 336 alg->finup = shash_default_finup; 337 if (!alg->digest) 338 alg->digest = shash_default_digest; 339 if (!alg->export) 340 alg->halg.statesize = alg->descsize; 341 if (!alg->setkey) 342 alg->setkey = shash_no_setkey; 343 344 return 0; 345 } 346 347 int crypto_register_shash(struct shash_alg *alg) 348 { 349 struct crypto_alg *base = &alg->base; 350 int err; 351 352 err = shash_prepare_alg(alg); 353 if (err) 354 return err; 355 356 return crypto_register_alg(base); 357 } 358 EXPORT_SYMBOL_GPL(crypto_register_shash); 359 360 void crypto_unregister_shash(struct shash_alg *alg) 361 { 362 crypto_unregister_alg(&alg->base); 363 } 364 EXPORT_SYMBOL_GPL(crypto_unregister_shash); 365 366 int crypto_register_shashes(struct shash_alg *algs, int count) 367 { 368 int i, ret; 369 370 for (i = 0; i < count; i++) { 371 ret = crypto_register_shash(&algs[i]); 372 if (ret) 373 goto err; 374 } 375 376 return 0; 377 378 err: 379 for (--i; i >= 0; --i) 380 crypto_unregister_shash(&algs[i]); 381 382 return ret; 383 } 384 EXPORT_SYMBOL_GPL(crypto_register_shashes); 385 386 void crypto_unregister_shashes(struct shash_alg *algs, int count) 387 { 388 int i; 389 390 for (i = count - 1; i >= 0; --i) 391 crypto_unregister_shash(&algs[i]); 392 } 393 EXPORT_SYMBOL_GPL(crypto_unregister_shashes); 394 395 int shash_register_instance(struct crypto_template *tmpl, 396 struct shash_instance *inst) 397 { 398 int err; 399 400 if (WARN_ON(!inst->free)) 401 return -EINVAL; 402 403 err = shash_prepare_alg(&inst->alg); 404 if (err) 405 return err; 406 407 return crypto_register_instance(tmpl, shash_crypto_instance(inst)); 408 } 409 EXPORT_SYMBOL_GPL(shash_register_instance); 410 411 void shash_free_singlespawn_instance(struct shash_instance *inst) 412 { 413 crypto_drop_spawn(shash_instance_ctx(inst)); 414 kfree(inst); 415 } 416 EXPORT_SYMBOL_GPL(shash_free_singlespawn_instance); 417 418 MODULE_LICENSE("GPL"); 419 MODULE_DESCRIPTION("Synchronous cryptographic hash type"); 420