* Copyright 2009 Colin Percival
* 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.
*/
#include <sys/types.h>
#include <sys/mman.h>
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "pbkdf2.h"
#include "crypto_scrypt_smix.h"
#include "crypto_scrypt.h"
* crypto_scrypt(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.
*/
int
crypto_scrypt(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)
{
void * B0, * V0, * XY0;
uint8_t * B;
uint32_t * V;
uint32_t * XY;
size_t r = _r, p = _p;
uint32_t i;
#if SIZE_MAX > UINT32_MAX
if (buflen > (((uint64_t)(1) << 32) - 1) * 32) {
errno = EFBIG;
goto err0;
}
#endif
if ((uint64_t)(r) * (uint64_t)(p) >= (1 << 30)) {
errno = EFBIG;
goto err0;
}
if (((N & (N - 1)) != 0) || (N < 2)) {
errno = EINVAL;
goto err0;
}
if ((r > SIZE_MAX / 128 / p) ||
#if SIZE_MAX / 256 <= UINT32_MAX
(r > (SIZE_MAX - 64) / 256) ||
#endif
(N > SIZE_MAX / 128 / r)) {
errno = ENOMEM;
goto err0;
}
#ifdef HAVE_POSIX_MEMALIGN
if ((errno = posix_memalign(&B0, 64, 128 * r * p)) != 0)
goto err0;
B = (uint8_t *)(B0);
if ((errno = posix_memalign(&XY0, 64, 256 * r + 64)) != 0)
goto err1;
XY = (uint32_t *)(XY0);
#if !defined(MAP_ANON) || !defined(HAVE_MMAP)
if ((errno = posix_memalign(&V0, 64, 128 * r * N)) != 0)
goto err2;
V = (uint32_t *)(V0);
#endif
#else
if ((B0 = malloc(128 * r * p + 63)) == NULL)
goto err0;
B = (uint8_t *)(((uintptr_t)(B0) + 63) & ~ (uintptr_t)(63));
if ((XY0 = malloc(256 * r + 64 + 63)) == NULL)
goto err1;
XY = (uint32_t *)(((uintptr_t)(XY0) + 63) & ~ (uintptr_t)(63));
#if !defined(MAP_ANON) || !defined(HAVE_MMAP)
if ((V0 = malloc(128 * r * N + 63)) == NULL)
goto err2;
V = (uint32_t *)(((uintptr_t)(V0) + 63) & ~ (uintptr_t)(63));
#endif
#endif
#if defined(MAP_ANON) && defined(HAVE_MMAP)
if ((V0 = mmap(NULL, 128 * r * N, PROT_READ | PROT_WRITE,
#ifdef MAP_NOCORE
MAP_ANON | MAP_PRIVATE | MAP_NOCORE,
#else
MAP_ANON | MAP_PRIVATE,
#endif
-1, 0)) == MAP_FAILED)
goto err2;
V = (uint32_t *)(V0);
#endif
PBKDF2_SHA256(passwd, passwdlen, salt, saltlen, 1, B, p * 128 * r);
for (i = 0; i < p; i++) {
crypto_scrypt_smix(&B[i * 128 * r], r, N, V, XY);
}
PBKDF2_SHA256(passwd, passwdlen, B, p * 128 * r, 1, buf, buflen);
#if defined(MAP_ANON) && defined(HAVE_MMAP)
if (munmap(V0, 128 * r * N))
goto err2;
#else
free(V0);
#endif
free(XY0);
free(B0);
return (0);
err2:
free(XY0);
err1:
free(B0);
err0:
return (-1);
}