/*
* Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
*
* All rights reserved.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License version 3.0 only,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* version 3.0 for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* version 3.0 along with this program. If not, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#import "OFHMAC.h"
#import "OFSHA256Hash.h"
#import "OFSecureData.h"
#import "OFInvalidArgumentException.h"
#import "OFOutOfMemoryException.h"
#import "OFOutOfRangeException.h"
#import "OFScrypt.h"
#import "OFPBKDF2.h"
void
_OFSalsa20_8Core(uint32_t buffer[16])
{
uint32_t tmp[16];
for (uint_fast8_t i = 0; i < 16; i++)
tmp[i] = OFToLittleEndian32(buffer[i]);
for (uint_fast8_t i = 0; i < 8; i += 2) {
tmp[ 4] ^= OFRotateLeft(tmp[ 0] + tmp[12], 7);
tmp[ 8] ^= OFRotateLeft(tmp[ 4] + tmp[ 0], 9);
tmp[12] ^= OFRotateLeft(tmp[ 8] + tmp[ 4], 13);
tmp[ 0] ^= OFRotateLeft(tmp[12] + tmp[ 8], 18);
tmp[ 9] ^= OFRotateLeft(tmp[ 5] + tmp[ 1], 7);
tmp[13] ^= OFRotateLeft(tmp[ 9] + tmp[ 5], 9);
tmp[ 1] ^= OFRotateLeft(tmp[13] + tmp[ 9], 13);
tmp[ 5] ^= OFRotateLeft(tmp[ 1] + tmp[13], 18);
tmp[14] ^= OFRotateLeft(tmp[10] + tmp[ 6], 7);
tmp[ 2] ^= OFRotateLeft(tmp[14] + tmp[10], 9);
tmp[ 6] ^= OFRotateLeft(tmp[ 2] + tmp[14], 13);
tmp[10] ^= OFRotateLeft(tmp[ 6] + tmp[ 2], 18);
tmp[ 3] ^= OFRotateLeft(tmp[15] + tmp[11], 7);
tmp[ 7] ^= OFRotateLeft(tmp[ 3] + tmp[15], 9);
tmp[11] ^= OFRotateLeft(tmp[ 7] + tmp[ 3], 13);
tmp[15] ^= OFRotateLeft(tmp[11] + tmp[ 7], 18);
tmp[ 1] ^= OFRotateLeft(tmp[ 0] + tmp[ 3], 7);
tmp[ 2] ^= OFRotateLeft(tmp[ 1] + tmp[ 0], 9);
tmp[ 3] ^= OFRotateLeft(tmp[ 2] + tmp[ 1], 13);
tmp[ 0] ^= OFRotateLeft(tmp[ 3] + tmp[ 2], 18);
tmp[ 6] ^= OFRotateLeft(tmp[ 5] + tmp[ 4], 7);
tmp[ 7] ^= OFRotateLeft(tmp[ 6] + tmp[ 5], 9);
tmp[ 4] ^= OFRotateLeft(tmp[ 7] + tmp[ 6], 13);
tmp[ 5] ^= OFRotateLeft(tmp[ 4] + tmp[ 7], 18);
tmp[11] ^= OFRotateLeft(tmp[10] + tmp[ 9], 7);
tmp[ 8] ^= OFRotateLeft(tmp[11] + tmp[10], 9);
tmp[ 9] ^= OFRotateLeft(tmp[ 8] + tmp[11], 13);
tmp[10] ^= OFRotateLeft(tmp[ 9] + tmp[ 8], 18);
tmp[12] ^= OFRotateLeft(tmp[15] + tmp[14], 7);
tmp[13] ^= OFRotateLeft(tmp[12] + tmp[15], 9);
tmp[14] ^= OFRotateLeft(tmp[13] + tmp[12], 13);
tmp[15] ^= OFRotateLeft(tmp[14] + tmp[13], 18);
}
for (uint_fast8_t i = 0; i < 16; i++)
buffer[i] = OFToLittleEndian32(OFFromLittleEndian32(buffer[i]) +
tmp[i]);
OFZeroMemory(tmp, sizeof(tmp));
}
void
_OFScryptBlockMix(uint32_t *output, const uint32_t *input, size_t blockSize)
{
uint32_t tmp[16];
/* Check defined here and executed in OFScrypt() */
#define OVERFLOW_CHECK_1 \
if (param.blockSize > SIZE_MAX / 2 || \
2 * param.blockSize - 1 > SIZE_MAX / 16) \
@throw [OFOutOfRangeException exception];
memcpy(tmp, input + (2 * blockSize - 1) * 16, 64);
for (size_t i = 0; i < 2 * blockSize; i++) {
for (size_t j = 0; j < 16; j++)
tmp[j] ^= input[i * 16 + j];
_OFSalsa20_8Core(tmp);
/*
* Even indices are stored in the first half and odd ones in
* the second.
*/
memcpy(output + ((i / 2) + (i & 1) * blockSize) * 16, tmp, 64);
}
OFZeroMemory(tmp, sizeof(tmp));
}
void
_OFScryptROMix(uint32_t *buffer, size_t blockSize, size_t costFactor,
uint32_t *tmp)
{
/* Check defined here and executed in OFScrypt() */
#define OVERFLOW_CHECK_2 \
if (param.blockSize > SIZE_MAX / 128 / param.costFactor) \
@throw [OFOutOfRangeException exception];
uint32_t *tmp2 = tmp + 32 * blockSize;
memcpy(tmp, buffer, 128 * blockSize);
for (size_t i = 0; i < costFactor; i++) {
memcpy(tmp2 + i * 32 * blockSize, tmp, 128 * blockSize);
_OFScryptBlockMix(tmp, tmp2 + i * 32 * blockSize, blockSize);
}
for (size_t i = 0; i < costFactor; i++) {
uint32_t j = OFFromLittleEndian32(
tmp[(2 * blockSize - 1) * 16]) & (costFactor - 1);
for (size_t k = 0; k < 32 * blockSize; k++)
tmp[k] ^= tmp2[j * 32 * blockSize + k];
_OFScryptBlockMix(buffer, tmp, blockSize);
if (i < costFactor - 1)
memcpy(tmp, buffer, 128 * blockSize);
}
}
void
OFScrypt(OFScryptParameters param)
{
OFSecureData *tmp = nil, *buffer = nil;
OFHMAC *HMAC = nil;
if (param.blockSize == 0 || param.costFactor <= 1 ||
(param.costFactor & (param.costFactor - 1)) != 0 ||
param.parallelization == 0)
@throw [OFInvalidArgumentException exception];
/*
* These are defined by the functions above. They are defined there so
* that the check is next to the code and easy to verify, but actually
* checked here for performance.
*/
OVERFLOW_CHECK_1
OVERFLOW_CHECK_2
@try {
uint32_t *tmpItems, *bufferItems;
if (param.costFactor > SIZE_MAX - 1 ||
(param.costFactor + 1) > SIZE_MAX / 128)
@throw [OFOutOfRangeException exception];
tmp = [[OFSecureData alloc]
initWithCount: (param.costFactor + 1) * 128
itemSize: param.blockSize
allowsSwappableMemory: param.allowsSwappableMemory];
tmpItems = tmp.mutableItems;
if (param.parallelization > SIZE_MAX / 128)
@throw [OFOutOfRangeException exception];
buffer = [[OFSecureData alloc]
initWithCount: param.parallelization * 128
itemSize: param.blockSize
allowsSwappableMemory: param.allowsSwappableMemory];
bufferItems = buffer.mutableItems;
HMAC = [[OFHMAC alloc]
initWithHashClass: [OFSHA256Hash class]
allowsSwappableMemory: param.allowsSwappableMemory];
OFPBKDF2((OFPBKDF2Parameters){
.HMAC = HMAC,
.iterations = 1,
.salt = param.salt,
.saltLength = param.saltLength,
.password = param.password,
.passwordLength = param.passwordLength,
.key = (unsigned char *)bufferItems,
.keyLength = param.parallelization * 128 *
param.blockSize,
.allowsSwappableMemory = param.allowsSwappableMemory
});
for (size_t i = 0; i < param.parallelization; i++)
_OFScryptROMix(bufferItems + i * 32 * param.blockSize,
param.blockSize, param.costFactor, tmpItems);
OFPBKDF2((OFPBKDF2Parameters){
.HMAC = HMAC,
.iterations = 1,
.salt = (unsigned char *)bufferItems,
.saltLength = param.parallelization * 128 *
param.blockSize,
.password = param.password,
.passwordLength = param.passwordLength,
.key = param.key,
.keyLength = param.keyLength,
.allowsSwappableMemory = param.allowsSwappableMemory
});
} @finally {
[tmp release];
[buffer release];
[HMAC release];
}
}