/*
* Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016
* Jonathan Schleifer <js@heap.zone>
*
* All rights reserved.
*
* This file is part of ObjFW. It may be distributed under the terms of the
* Q Public License 1.0, which can be found in the file LICENSE.QPL included in
* the packaging of this file.
*
* Alternatively, it may be distributed under the terms of the GNU General
* Public License, either version 2 or 3, which can be found in the file
* LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
* file.
*/
#include "config.h"
#include <stdlib.h>
#import "OFHMAC.h"
#import "OFInvalidArgumentException.h"
#import "OFOutOfMemoryException.h"
#import "OFOutOfRangeException.h"
#import "pbkdf2.h"
void of_pbkdf2(OFHMAC *HMAC, size_t iterations,
const unsigned char *salt, size_t saltLength,
const char *password, size_t passwordLength,
unsigned char *key, size_t keyLength)
{
size_t blocks, digestSize = [HMAC digestSize];
unsigned char *extendedSalt;
unsigned char buffer[digestSize];
unsigned char digest[digestSize];
if (HMAC == nil || iterations == 0 || salt == NULL ||
password == NULL || key == NULL || keyLength == 0)
@throw [OFInvalidArgumentException exception];
blocks = keyLength / digestSize;
if (keyLength % digestSize != 0)
blocks++;
if (saltLength > SIZE_MAX - 4 || blocks > UINT32_MAX)
@throw [OFOutOfRangeException exception];
if ((extendedSalt = malloc(saltLength + 4)) == NULL)
@throw [OFOutOfMemoryException
exceptionWithRequestedSize: saltLength + 4];
@try {
uint32_t i = OF_BSWAP32_IF_LE(1);
[HMAC setKey: password
length: passwordLength];
memcpy(extendedSalt, salt, saltLength);
while (keyLength > 0) {
size_t length;
memcpy(extendedSalt + saltLength, &i, 4);
[HMAC reset];
[HMAC updateWithBuffer: extendedSalt
length: saltLength + 4];
memcpy(buffer, [HMAC digest], digestSize);
memcpy(digest, [HMAC digest], digestSize);
for (size_t j = 1; j < iterations; j++) {
[HMAC reset];
[HMAC updateWithBuffer: digest
length: digestSize];
memcpy(digest, [HMAC digest], digestSize);
for (size_t k = 0; k < digestSize; k++)
buffer[k] ^= digest[k];
}
length = digestSize;
if (length > keyLength)
length = keyLength;
memcpy(key, buffer, length);
key += length;
keyLength -= length;
i = OF_BSWAP32_IF_LE(OF_BSWAP32_IF_LE(i) + 1);
}
} @finally {
of_explicit_memset(extendedSalt, 0, saltLength + 4);
of_explicit_memset(buffer, 0, digestSize);
of_explicit_memset(digest, 0, digestSize);
[HMAC zero];
free(extendedSalt);
}
}