diff options
Diffstat (limited to 'crypto/shash.c')
| -rw-r--r-- | crypto/shash.c | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/crypto/shash.c b/crypto/shash.c new file mode 100644 index 000000000..0a0a50cb6 --- /dev/null +++ b/crypto/shash.c @@ -0,0 +1,627 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Synchronous Cryptographic Hash operations. + * + * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> + */ + +#include <crypto/scatterwalk.h> +#include <crypto/internal/hash.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/seq_file.h> +#include <linux/cryptouser.h> +#include <net/netlink.h> +#include <linux/compiler.h> + +#include "internal.h" + +static const struct crypto_type crypto_shash_type; + +static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + return -ENOSYS; +} + +/* + * Check whether an shash algorithm has a setkey function. + * + * For CFI compatibility, this must not be an inline function. This is because + * when CFI is enabled, modules won't get the same address for shash_no_setkey + * (if it were exported, which inlining would require) as the core kernel will. + */ +bool crypto_shash_alg_has_setkey(struct shash_alg *alg) +{ + return alg->setkey != shash_no_setkey; +} +EXPORT_SYMBOL_GPL(crypto_shash_alg_has_setkey); + +static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + unsigned long absize; + u8 *buffer, *alignbuffer; + int err; + + absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1)); + buffer = kmalloc(absize, GFP_ATOMIC); + if (!buffer) + return -ENOMEM; + + alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + memcpy(alignbuffer, key, keylen); + err = shash->setkey(tfm, alignbuffer, keylen); + kfree_sensitive(buffer); + return err; +} + +static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg) +{ + if (crypto_shash_alg_needs_key(alg)) + crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY); +} + +int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + int err; + + if ((unsigned long)key & alignmask) + err = shash_setkey_unaligned(tfm, key, keylen); + else + err = shash->setkey(tfm, key, keylen); + + if (unlikely(err)) { + shash_set_needkey(tfm, shash); + return err; + } + + crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); + return 0; +} +EXPORT_SYMBOL_GPL(crypto_shash_setkey); + +static int shash_update_unaligned(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + unsigned int unaligned_len = alignmask + 1 - + ((unsigned long)data & alignmask); + /* + * We cannot count on __aligned() working for large values: + * https://patchwork.kernel.org/patch/9507697/ + */ + u8 ubuf[MAX_ALGAPI_ALIGNMASK * 2]; + u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1); + int err; + + if (WARN_ON(buf + unaligned_len > ubuf + sizeof(ubuf))) + return -EINVAL; + + if (unaligned_len > len) + unaligned_len = len; + + memcpy(buf, data, unaligned_len); + err = shash->update(desc, buf, unaligned_len); + memset(buf, 0, unaligned_len); + + return err ?: + shash->update(desc, data + unaligned_len, len - unaligned_len); +} + +int crypto_shash_update(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if ((unsigned long)data & alignmask) + return shash_update_unaligned(desc, data, len); + + return shash->update(desc, data, len); +} +EXPORT_SYMBOL_GPL(crypto_shash_update); + +static int shash_final_unaligned(struct shash_desc *desc, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + unsigned long alignmask = crypto_shash_alignmask(tfm); + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned int ds = crypto_shash_digestsize(tfm); + /* + * We cannot count on __aligned() working for large values: + * https://patchwork.kernel.org/patch/9507697/ + */ + u8 ubuf[MAX_ALGAPI_ALIGNMASK + HASH_MAX_DIGESTSIZE]; + u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1); + int err; + + if (WARN_ON(buf + ds > ubuf + sizeof(ubuf))) + return -EINVAL; + + err = shash->final(desc, buf); + if (err) + goto out; + + memcpy(out, buf, ds); + +out: + memset(buf, 0, ds); + return err; +} + +int crypto_shash_final(struct shash_desc *desc, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if ((unsigned long)out & alignmask) + return shash_final_unaligned(desc, out); + + return shash->final(desc, out); +} +EXPORT_SYMBOL_GPL(crypto_shash_final); + +static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + return crypto_shash_update(desc, data, len) ?: + crypto_shash_final(desc, out); +} + +int crypto_shash_finup(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if (((unsigned long)data | (unsigned long)out) & alignmask) + return shash_finup_unaligned(desc, data, len, out); + + return shash->finup(desc, data, len, out); +} +EXPORT_SYMBOL_GPL(crypto_shash_finup); + +static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + return crypto_shash_init(desc) ?: + crypto_shash_finup(desc, data, len, out); +} + +int crypto_shash_digest(struct shash_desc *desc, const u8 *data, + unsigned int len, u8 *out) +{ + struct crypto_shash *tfm = desc->tfm; + struct shash_alg *shash = crypto_shash_alg(tfm); + unsigned long alignmask = crypto_shash_alignmask(tfm); + + if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) + return -ENOKEY; + + if (((unsigned long)data | (unsigned long)out) & alignmask) + return shash_digest_unaligned(desc, data, len, out); + + return shash->digest(desc, data, len, out); +} +EXPORT_SYMBOL_GPL(crypto_shash_digest); + +int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data, + unsigned int len, u8 *out) +{ + SHASH_DESC_ON_STACK(desc, tfm); + int err; + + desc->tfm = tfm; + + err = crypto_shash_digest(desc, data, len, out); + + shash_desc_zero(desc); + + return err; +} +EXPORT_SYMBOL_GPL(crypto_shash_tfm_digest); + +static int shash_default_export(struct shash_desc *desc, void *out) +{ + memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm)); + return 0; +} + +static int shash_default_import(struct shash_desc *desc, const void *in) +{ + memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm)); + return 0; +} + +static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key, + unsigned int keylen) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(tfm); + + return crypto_shash_setkey(*ctx, key, keylen); +} + +static int shash_async_init(struct ahash_request *req) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); + struct shash_desc *desc = ahash_request_ctx(req); + + desc->tfm = *ctx; + + return crypto_shash_init(desc); +} + +int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc) +{ + struct crypto_hash_walk walk; + int nbytes; + + for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0; + nbytes = crypto_hash_walk_done(&walk, nbytes)) + nbytes = crypto_shash_update(desc, walk.data, nbytes); + + return nbytes; +} +EXPORT_SYMBOL_GPL(shash_ahash_update); + +static int shash_async_update(struct ahash_request *req) +{ + return shash_ahash_update(req, ahash_request_ctx(req)); +} + +static int shash_async_final(struct ahash_request *req) +{ + return crypto_shash_final(ahash_request_ctx(req), req->result); +} + +int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc) +{ + struct crypto_hash_walk walk; + int nbytes; + + nbytes = crypto_hash_walk_first(req, &walk); + if (!nbytes) + return crypto_shash_final(desc, req->result); + + do { + nbytes = crypto_hash_walk_last(&walk) ? + crypto_shash_finup(desc, walk.data, nbytes, + req->result) : + crypto_shash_update(desc, walk.data, nbytes); + nbytes = crypto_hash_walk_done(&walk, nbytes); + } while (nbytes > 0); + + return nbytes; +} +EXPORT_SYMBOL_GPL(shash_ahash_finup); + +static int shash_async_finup(struct ahash_request *req) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); + struct shash_desc *desc = ahash_request_ctx(req); + + desc->tfm = *ctx; + + return shash_ahash_finup(req, desc); +} + +int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc) +{ + unsigned int nbytes = req->nbytes; + struct scatterlist *sg; + unsigned int offset; + int err; + + if (nbytes && + (sg = req->src, offset = sg->offset, + nbytes <= min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) { + void *data; + + data = kmap_atomic(sg_page(sg)); + err = crypto_shash_digest(desc, data + offset, nbytes, + req->result); + kunmap_atomic(data); + } else + err = crypto_shash_init(desc) ?: + shash_ahash_finup(req, desc); + + return err; +} +EXPORT_SYMBOL_GPL(shash_ahash_digest); + +static int shash_async_digest(struct ahash_request *req) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); + struct shash_desc *desc = ahash_request_ctx(req); + + desc->tfm = *ctx; + + return shash_ahash_digest(req, desc); +} + +static int shash_async_export(struct ahash_request *req, void *out) +{ + return crypto_shash_export(ahash_request_ctx(req), out); +} + +static int shash_async_import(struct ahash_request *req, const void *in) +{ + struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req)); + struct shash_desc *desc = ahash_request_ctx(req); + + desc->tfm = *ctx; + + return crypto_shash_import(desc, in); +} + +static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm) +{ + struct crypto_shash **ctx = crypto_tfm_ctx(tfm); + + crypto_free_shash(*ctx); +} + +int crypto_init_shash_ops_async(struct crypto_tfm *tfm) +{ + struct crypto_alg *calg = tfm->__crt_alg; + struct shash_alg *alg = __crypto_shash_alg(calg); + struct crypto_ahash *crt = __crypto_ahash_cast(tfm); + struct crypto_shash **ctx = crypto_tfm_ctx(tfm); + struct crypto_shash *shash; + + if (!crypto_mod_get(calg)) + return -EAGAIN; + + shash = crypto_create_tfm(calg, &crypto_shash_type); + if (IS_ERR(shash)) { + crypto_mod_put(calg); + return PTR_ERR(shash); + } + + *ctx = shash; + tfm->exit = crypto_exit_shash_ops_async; + + crt->init = shash_async_init; + crt->update = shash_async_update; + crt->final = shash_async_final; + crt->finup = shash_async_finup; + crt->digest = shash_async_digest; + if (crypto_shash_alg_has_setkey(alg)) + crt->setkey = shash_async_setkey; + + crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) & + CRYPTO_TFM_NEED_KEY); + + crt->export = shash_async_export; + crt->import = shash_async_import; + + crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash); + + return 0; +} + +static void crypto_shash_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_shash *hash = __crypto_shash_cast(tfm); + struct shash_alg *alg = crypto_shash_alg(hash); + + alg->exit_tfm(hash); +} + +static int crypto_shash_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_shash *hash = __crypto_shash_cast(tfm); + struct shash_alg *alg = crypto_shash_alg(hash); + int err; + + hash->descsize = alg->descsize; + + shash_set_needkey(hash, alg); + + if (alg->exit_tfm) + tfm->exit = crypto_shash_exit_tfm; + + if (!alg->init_tfm) + return 0; + + err = alg->init_tfm(hash); + if (err) + return err; + + /* ->init_tfm() may have increased the descsize. */ + if (WARN_ON_ONCE(hash->descsize > HASH_MAX_DESCSIZE)) { + if (alg->exit_tfm) + alg->exit_tfm(hash); + return -EINVAL; + } + + return 0; +} + +static void crypto_shash_free_instance(struct crypto_instance *inst) +{ + struct shash_instance *shash = shash_instance(inst); + + shash->free(shash); +} + +#ifdef CONFIG_NET +static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg) +{ + struct crypto_report_hash rhash; + struct shash_alg *salg = __crypto_shash_alg(alg); + + memset(&rhash, 0, sizeof(rhash)); + + strscpy(rhash.type, "shash", sizeof(rhash.type)); + + rhash.blocksize = alg->cra_blocksize; + rhash.digestsize = salg->digestsize; + + return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash); +} +#else +static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg) +{ + return -ENOSYS; +} +#endif + +static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) + __maybe_unused; +static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg) +{ + struct shash_alg *salg = __crypto_shash_alg(alg); + + seq_printf(m, "type : shash\n"); + seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); + seq_printf(m, "digestsize : %u\n", salg->digestsize); +} + +static const struct crypto_type crypto_shash_type = { + .extsize = crypto_alg_extsize, + .init_tfm = crypto_shash_init_tfm, + .free = crypto_shash_free_instance, +#ifdef CONFIG_PROC_FS + .show = crypto_shash_show, +#endif + .report = crypto_shash_report, + .maskclear = ~CRYPTO_ALG_TYPE_MASK, + .maskset = CRYPTO_ALG_TYPE_MASK, + .type = CRYPTO_ALG_TYPE_SHASH, + .tfmsize = offsetof(struct crypto_shash, base), +}; + +int crypto_grab_shash(struct crypto_shash_spawn *spawn, + struct crypto_instance *inst, + const char *name, u32 type, u32 mask) +{ + spawn->base.frontend = &crypto_shash_type; + return crypto_grab_spawn(&spawn->base, inst, name, type, mask); +} +EXPORT_SYMBOL_GPL(crypto_grab_shash); + +struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, + u32 mask) +{ + return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask); +} +EXPORT_SYMBOL_GPL(crypto_alloc_shash); + +static int shash_prepare_alg(struct shash_alg *alg) +{ + struct crypto_alg *base = &alg->base; + + if (alg->digestsize > HASH_MAX_DIGESTSIZE || + alg->descsize > HASH_MAX_DESCSIZE || + alg->statesize > HASH_MAX_STATESIZE) + return -EINVAL; + + if ((alg->export && !alg->import) || (alg->import && !alg->export)) + return -EINVAL; + + base->cra_type = &crypto_shash_type; + base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; + base->cra_flags |= CRYPTO_ALG_TYPE_SHASH; + + if (!alg->finup) + alg->finup = shash_finup_unaligned; + if (!alg->digest) + alg->digest = shash_digest_unaligned; + if (!alg->export) { + alg->export = shash_default_export; + alg->import = shash_default_import; + alg->statesize = alg->descsize; + } + if (!alg->setkey) + alg->setkey = shash_no_setkey; + + return 0; +} + +int crypto_register_shash(struct shash_alg *alg) +{ + struct crypto_alg *base = &alg->base; + int err; + + err = shash_prepare_alg(alg); + if (err) + return err; + + return crypto_register_alg(base); +} +EXPORT_SYMBOL_GPL(crypto_register_shash); + +void crypto_unregister_shash(struct shash_alg *alg) +{ + crypto_unregister_alg(&alg->base); +} +EXPORT_SYMBOL_GPL(crypto_unregister_shash); + +int crypto_register_shashes(struct shash_alg *algs, int count) +{ + int i, ret; + + for (i = 0; i < count; i++) { + ret = crypto_register_shash(&algs[i]); + if (ret) + goto err; + } + + return 0; + +err: + for (--i; i >= 0; --i) + crypto_unregister_shash(&algs[i]); + + return ret; +} +EXPORT_SYMBOL_GPL(crypto_register_shashes); + +void crypto_unregister_shashes(struct shash_alg *algs, int count) +{ + int i; + + for (i = count - 1; i >= 0; --i) + crypto_unregister_shash(&algs[i]); +} +EXPORT_SYMBOL_GPL(crypto_unregister_shashes); + +int shash_register_instance(struct crypto_template *tmpl, + struct shash_instance *inst) +{ + int err; + + if (WARN_ON(!inst->free)) + return -EINVAL; + + err = shash_prepare_alg(&inst->alg); + if (err) + return err; + + return crypto_register_instance(tmpl, shash_crypto_instance(inst)); +} +EXPORT_SYMBOL_GPL(shash_register_instance); + +void shash_free_singlespawn_instance(struct shash_instance *inst) +{ + crypto_drop_spawn(shash_instance_ctx(inst)); + kfree(inst); +} +EXPORT_SYMBOL_GPL(shash_free_singlespawn_instance); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Synchronous cryptographic hash type"); |