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1// SPDX-License-Identifier: GPL-2.0-or-later2/*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 19int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,20 unsigned int keylen)21{22 return -ENOSYS;23}24EXPORT_SYMBOL_GPL(shash_no_setkey);25 26static 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 32int 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}47EXPORT_SYMBOL_GPL(crypto_shash_setkey);48 49int 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}54EXPORT_SYMBOL_GPL(crypto_shash_update);55 56int crypto_shash_final(struct shash_desc *desc, u8 *out)57{58 return crypto_shash_alg(desc->tfm)->final(desc, out);59}60EXPORT_SYMBOL_GPL(crypto_shash_final);61 62static 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 71int 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}76EXPORT_SYMBOL_GPL(crypto_shash_finup);77 78static 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 87int 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}97EXPORT_SYMBOL_GPL(crypto_shash_digest);98 99int 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}113EXPORT_SYMBOL_GPL(crypto_shash_tfm_digest);114 115int 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}126EXPORT_SYMBOL_GPL(crypto_shash_export);127 128int 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}142EXPORT_SYMBOL_GPL(crypto_shash_import);143 144static 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 152static 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 182static 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 189static 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 205static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)206 __maybe_unused;207static 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 216const 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_FS221 .show = crypto_shash_show,222#endif223#if IS_ENABLED(CONFIG_CRYPTO_USER)224 .report = crypto_shash_report,225#endif226 .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 232int 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}239EXPORT_SYMBOL_GPL(crypto_grab_shash);240 241struct 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}246EXPORT_SYMBOL_GPL(crypto_alloc_shash);247 248int 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}252EXPORT_SYMBOL_GPL(crypto_has_shash);253 254struct 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}288EXPORT_SYMBOL_GPL(crypto_clone_shash);289 290int 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 306static 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 either326 * install a default here, or we can leave the pointer as NULL and check327 * the pointer for NULL in crypto_shash_*(), avoiding an indirect call328 * when the default behavior is desired. For ->finup and ->digest we329 * install defaults, since for optimal performance algorithms should330 * implement these anyway. On the other hand, for ->import and331 * ->export the common case and best performance comes from the simple332 * memcpy of the shash_desc_ctx, so when those pointers are NULL we333 * 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 347int 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}358EXPORT_SYMBOL_GPL(crypto_register_shash);359 360void crypto_unregister_shash(struct shash_alg *alg)361{362 crypto_unregister_alg(&alg->base);363}364EXPORT_SYMBOL_GPL(crypto_unregister_shash);365 366int 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 378err:379 for (--i; i >= 0; --i)380 crypto_unregister_shash(&algs[i]);381 382 return ret;383}384EXPORT_SYMBOL_GPL(crypto_register_shashes);385 386void 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}393EXPORT_SYMBOL_GPL(crypto_unregister_shashes);394 395int 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}409EXPORT_SYMBOL_GPL(shash_register_instance);410 411void shash_free_singlespawn_instance(struct shash_instance *inst)412{413 crypto_drop_spawn(shash_instance_ctx(inst));414 kfree(inst);415}416EXPORT_SYMBOL_GPL(shash_free_singlespawn_instance);417 418MODULE_LICENSE("GPL");419MODULE_DESCRIPTION("Synchronous cryptographic hash type");420