linux/crypto/shash.c

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/*
* Synchronous Cryptographic Hash operations.
*
* Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#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>
static inline struct crypto_shash *__crypto_shash_cast(struct crypto_tfm *tfm)
{
return container_of(tfm, struct crypto_shash, base);
}
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_MINALIGN - 1));
buffer = kmalloc(absize, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
memcpy(alignbuffer, key, keylen);
err = shash->setkey(tfm, alignbuffer, keylen);
memset(alignbuffer, 0, keylen);
kfree(buffer);
return err;
}
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);
if ((unsigned long)key & alignmask)
return shash_setkey_unaligned(tfm, key, keylen);
return shash->setkey(tfm, key, keylen);
}
EXPORT_SYMBOL_GPL(crypto_shash_setkey);
static inline unsigned int shash_align_buffer_size(unsigned len,
unsigned long mask)
{
return len + (mask & ~(__alignof__(u8 __attribute__ ((aligned))) - 1));
}
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);
u8 buf[shash_align_buffer_size(unaligned_len, alignmask)]
__attribute__ ((aligned));
memcpy(buf, data, unaligned_len);
return shash->update(desc, buf, unaligned_len) ?:
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);
u8 buf[shash_align_buffer_size(ds, alignmask)]
__attribute__ ((aligned));
int err;
err = shash->final(desc, buf);
memcpy(out, buf, 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 ||
!shash->finup)
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_update(desc, data, len) ?:
crypto_shash_final(desc, 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 (((unsigned long)data | (unsigned long)out) & alignmask ||
!shash->digest)
return shash_digest_unaligned(desc, data, len, out);
return shash->digest(desc, data, len, out);
}
EXPORT_SYMBOL_GPL(crypto_shash_digest);
static int crypto_shash_init_tfm(struct crypto_tfm *tfm,
const struct crypto_type *frontend)
{
if (frontend->type != CRYPTO_ALG_TYPE_SHASH)
return -EINVAL;
return 0;
}
static unsigned int crypto_shash_extsize(struct crypto_alg *alg,
const struct crypto_type *frontend)
{
return alg->cra_ctxsize;
}
static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
__attribute__ ((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);
seq_printf(m, "descsize : %u\n", salg->descsize);
}
static const struct crypto_type crypto_shash_type = {
.extsize = crypto_shash_extsize,
.init_tfm = crypto_shash_init_tfm,
#ifdef CONFIG_PROC_FS
.show = crypto_shash_show,
#endif
.maskclear = ~CRYPTO_ALG_TYPE_MASK,
.maskset = CRYPTO_ALG_TYPE_MASK,
.type = CRYPTO_ALG_TYPE_SHASH,
.tfmsize = offsetof(struct crypto_shash, base),
};
struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
u32 mask)
{
return __crypto_shash_cast(
crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask));
}
EXPORT_SYMBOL_GPL(crypto_alloc_shash);
int crypto_register_shash(struct shash_alg *alg)
{
struct crypto_alg *base = &alg->base;
if (alg->digestsize > PAGE_SIZE / 8 ||
alg->descsize > PAGE_SIZE / 8)
return -EINVAL;
base->cra_type = &crypto_shash_type;
base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_shash);
int crypto_unregister_shash(struct shash_alg *alg)
{
return crypto_unregister_alg(&alg->base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_shash);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Synchronous cryptographic hash type");