/*
 * Hash: Hash algorithms under the crypto API
 * 
 * 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.
 *
 */

#ifndef _CRYPTO_HASH_H
#define _CRYPTO_HASH_H

#include <linux/crypto.h>
#include <linux/string.h>

struct hash_alg_common {
	unsigned int digestsize;
	unsigned int statesize;

	struct crypto_alg base;
};

struct shash_desc {
	struct crypto_shash *tfm;
	u32 flags;

	void *__ctx[] CRYPTO_MINALIGN_ATTR;
};

#define SHASH_DESC_ON_STACK(shash, ctx)				  \
	char __##shash##_desc[sizeof(struct shash_desc) +	  \
		crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \
	struct shash_desc *shash = (struct shash_desc *)__##shash##_desc

struct shash_alg {
	int (*init)(struct shash_desc *desc);
	int (*update)(struct shash_desc *desc, const u8 *data,
		      unsigned int len);
	int (*final)(struct shash_desc *desc, u8 *out);
	int (*finup)(struct shash_desc *desc, const u8 *data,
		     unsigned int len, u8 *out);
	int (*digest)(struct shash_desc *desc, const u8 *data,
		      unsigned int len, u8 *out);
	int (*export)(struct shash_desc *desc, void *out);
	int (*import)(struct shash_desc *desc, const void *in);
	int (*setkey)(struct crypto_shash *tfm, const u8 *key,
		      unsigned int keylen);

	unsigned int descsize;

	/* These fields must match hash_alg_common. */
	unsigned int digestsize
		__attribute__ ((aligned(__alignof__(struct hash_alg_common))));
	unsigned int statesize;

	struct crypto_alg base;
};

struct crypto_shash {
	unsigned int descsize;
	struct crypto_tfm base;
};

struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
					u32 mask);

static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
{
	return &tfm->base;
}

static inline void crypto_free_shash(struct crypto_shash *tfm)
{
	crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
}

static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
{
	return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
}

static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
{
	return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
}

static inline unsigned int crypto_shash_alignmask(
	struct crypto_shash *tfm)
{
	return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
}

static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
{
	return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
}

static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
{
	return container_of(alg, struct shash_alg, base);
}

static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
{
	return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
}

static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
{
	return crypto_shash_alg(tfm)->digestsize;
}

static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
{
	return crypto_shash_alg(tfm)->statesize;
}

static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
{
	return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
}

static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
{
	crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
}

static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
{
	crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
}

static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
{
	return tfm->descsize;
}

static inline void *shash_desc_ctx(struct shash_desc *desc)
{
	return desc->__ctx;
}

int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
			unsigned int keylen);

int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
			unsigned int len, u8 *out);

static inline int crypto_shash_export(struct shash_desc *desc, void *out)
{
	return crypto_shash_alg(desc->tfm)->export(desc, out);
}

static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
{
	return crypto_shash_alg(desc->tfm)->import(desc, in);
}

static inline int crypto_shash_init(struct shash_desc *desc)
{
	return crypto_shash_alg(desc->tfm)->init(desc);
}

int crypto_shash_update(struct shash_desc *desc, const u8 *data,
			unsigned int len);

int crypto_shash_final(struct shash_desc *desc, u8 *out);

int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
		       unsigned int len, u8 *out);

static inline void shash_desc_zero(struct shash_desc *desc)
{
	memzero_explicit(desc,
			 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
}

#endif	/* _CRYPTO_HASH_H */