/*-
 * Copyright 2009 Colin Percival
 * Copyright 2013 Alexander Peslyak
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file was originally written by Colin Percival as part of the Tarsnap
 * online backup system.
 */
#ifndef _CRYPTO_SCRYPT_H_
#define _CRYPTO_SCRYPT_H_

#include <stdint.h>

#define crypto_pwhash_scryptxsalsa208sha256_STRPREFIXBYTES 14
#define crypto_pwhash_scryptxsalsa208sha256_STRSETTINGBYTES 57
#define crypto_pwhash_scryptxsalsa208sha256_STRSALTBYTES 32
#define crypto_pwhash_scryptxsalsa208sha256_STRSALTBYTES_ENCODED 43
#define crypto_pwhash_scryptxsalsa208sha256_STRHASHBYTES 32
#define crypto_pwhash_scryptxsalsa208sha256_STRHASHBYTES_ENCODED 43

#define BYTES2CHARS(bytes) ((((bytes) * 8) + 5) / 6)

/**
 * crypto_scrypt_compat(passwd, passwdlen, salt, saltlen, N, r, p, buf, buflen):
 * Compute scrypt(passwd[0 .. passwdlen - 1], salt[0 .. saltlen - 1], N, r,
 * p, buflen) and write the result into buf.  The parameters r, p, and buflen
 * must satisfy r * p < 2^30 and buflen <= (2^32 - 1) * 32.  The parameter N
 * must be a power of 2 greater than 1.
 *
 * Return 0 on success; or -1 on error.
 */
extern int crypto_scrypt_compat(const uint8_t * __passwd, size_t __passwdlen,
    const uint8_t * __salt, size_t __saltlen,
    uint64_t __N, uint32_t __r, uint32_t __p,
    uint8_t * __buf, size_t __buflen);

typedef struct {
	void * base, * aligned;
	size_t size;
} escrypt_region_t;

typedef escrypt_region_t escrypt_local_t;

extern int escrypt_init_local(escrypt_local_t * __local);

extern int escrypt_free_local(escrypt_local_t * __local);

extern void *alloc_region(escrypt_region_t * region, size_t size);
extern int free_region(escrypt_region_t * region);

typedef int (*escrypt_kdf_t)(escrypt_local_t * __local,
                             const uint8_t * __passwd, size_t __passwdlen,
                             const uint8_t * __salt, size_t __saltlen,
                             uint64_t __N, uint32_t __r, uint32_t __p,
                             uint8_t * __buf, size_t __buflen);

extern int escrypt_kdf_nosse(escrypt_local_t * __local,
    const uint8_t * __passwd, size_t __passwdlen,
    const uint8_t * __salt, size_t __saltlen,
    uint64_t __N, uint32_t __r, uint32_t __p,
    uint8_t * __buf, size_t __buflen);

extern int escrypt_kdf_sse(escrypt_local_t * __local,
    const uint8_t * __passwd, size_t __passwdlen,
    const uint8_t * __salt, size_t __saltlen,
    uint64_t __N, uint32_t __r, uint32_t __p,
    uint8_t * __buf, size_t __buflen);

extern uint8_t * escrypt_r(escrypt_local_t * __local,
    const uint8_t * __passwd, size_t __passwdlen,
    const uint8_t * __setting,
    uint8_t * __buf, size_t __buflen);

extern uint8_t * escrypt_gensalt_r(
    uint32_t __N_log2, uint32_t __r, uint32_t __p,
    const uint8_t * __src, size_t __srclen,
    uint8_t * __buf, size_t __buflen);

#endif /* !_CRYPTO_SCRYPT_H_ */