/*
* Argon2 reference source code package - reference C implementations
*
* Copyright 2015
* Daniel Dinu, Dmitry Khovratovich, Jean-Philippe Aumasson, and Samuel Neves
*
* You may use this work under the terms of a Creative Commons CC0 1.0
* License/Waiver or the Apache Public License 2.0, at your option. The terms of
* these licenses can be found at:
*
* - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
* - Apache 2.0 : http://www.apache.org/licenses/LICENSE-2.0
*
* You should have received a copy of both of these licenses along with this
* software. If not, they may be obtained at the above URLs.
*/
#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include "argon2.h"
#include "core.h"
#include "blake2/blamka-round-ref.h"
#include "blake2/blake2-impl.h"
#include "blake2/blake2.h"
/*
* Function fills a new memory block and optionally XORs the old block over the new one.
* @next_block must be initialized.
* @param prev_block Pointer to the previous block
* @param ref_block Pointer to the reference block
* @param next_block Pointer to the block to be constructed
* @param with_xor Whether to XOR into the new block (1) or just overwrite (0)
* @pre all block pointers must be valid
*/
static void fill_block(const block *prev_block, const block *ref_block,
block *next_block, int with_xor) {
block blockR, block_tmp;
unsigned i;
copy_block(&blockR, ref_block);
xor_block(&blockR, prev_block);
copy_block(&block_tmp, &blockR);
/* Now blockR = ref_block + prev_block and block_tmp = ref_block + prev_block */
if (with_xor) {
/* Saving the next block contents for XOR over: */
xor_block(&block_tmp, next_block);
/* Now blockR = ref_block + prev_block and
block_tmp = ref_block + prev_block + next_block */
}
/* Apply Blake2 on columns of 64-bit words: (0,1,...,15) , then
(16,17,..31)... finally (112,113,...127) */
for (i = 0; i < 8; ++i) {
BLAKE2_ROUND_NOMSG(
blockR.v[16 * i], blockR.v[16 * i + 1], blockR.v[16 * i + 2],
blockR.v[16 * i + 3], blockR.v[16 * i + 4], blockR.v[16 * i + 5],
blockR.v[16 * i + 6], blockR.v[16 * i + 7], blockR.v[16 * i + 8],
blockR.v[16 * i + 9], blockR.v[16 * i + 10], blockR.v[16 * i + 11],
blockR.v[16 * i + 12], blockR.v[16 * i + 13], blockR.v[16 * i + 14],
blockR.v[16 * i + 15]);
}
/* Apply Blake2 on rows of 64-bit words: (0,1,16,17,...112,113), then
(2,3,18,19,...,114,115).. finally (14,15,30,31,...,126,127) */
for (i = 0; i < 8; i++) {
BLAKE2_ROUND_NOMSG(
blockR.v[2 * i], blockR.v[2 * i + 1], blockR.v[2 * i + 16],
blockR.v[2 * i + 17], blockR.v[2 * i + 32], blockR.v[2 * i + 33],
blockR.v[2 * i + 48], blockR.v[2 * i + 49], blockR.v[2 * i + 64],
blockR.v[2 * i + 65], blockR.v[2 * i + 80], blockR.v[2 * i + 81],
blockR.v[2 * i + 96], blockR.v[2 * i + 97], blockR.v[2 * i + 112],
blockR.v[2 * i + 113]);
}
copy_block(next_block, &block_tmp);
xor_block(next_block, &blockR);
}
static void next_addresses(block *address_block, block *input_block,
const block *zero_block) {
input_block->v[6]++;
fill_block(zero_block, input_block, address_block, 0);
fill_block(zero_block, address_block, address_block, 0);
}
void fill_segment(const argon2_instance_t *instance,
argon2_position_t position) {
block *ref_block = NULL, *curr_block = NULL;
block address_block, input_block, zero_block;
uint64_t pseudo_rand, ref_index, ref_lane;
uint32_t prev_offset, curr_offset;
uint32_t starting_index;
uint32_t i;
int data_independent_addressing;
if (instance == NULL) {
return;
}
data_independent_addressing =
(instance->type == Argon2_i) ||
(instance->type == Argon2_id && (position.pass == 0) &&
(position.slice < ARGON2_SYNC_POINTS / 2));
if (data_independent_addressing) {
init_block_value(&zero_block, 0);
init_block_value(&input_block, 0);
input_block.v[0] = position.pass;
input_block.v[1] = position.lane;
input_block.v[2] = position.slice;
input_block.v[3] = instance->memory_blocks;
input_block.v[4] = instance->passes;
input_block.v[5] = instance->type;
}
starting_index = 0;
if ((0 == position.pass) && (0 == position.slice)) {
starting_index = 2; /* we have already generated the first two blocks */
/* Don't forget to generate the first block of addresses: */
if (data_independent_addressing) {
next_addresses(&address_block, &input_block, &zero_block);
}
}
/* Offset of the current block */
curr_offset = position.lane * instance->lane_length +
position.slice * instance->segment_length + starting_index;
if (0 == curr_offset % instance->lane_length) {
/* Last block in this lane */
prev_offset = curr_offset + instance->lane_length - 1;
} else {
/* Previous block */
prev_offset = curr_offset - 1;
}
for (i = starting_index; i < instance->segment_length;
++i, ++curr_offset, ++prev_offset) {
/*1.1 Rotating prev_offset if needed */
if (curr_offset % instance->lane_length == 1) {
prev_offset = curr_offset - 1;
}
/* 1.2 Computing the index of the reference block */
/* 1.2.1 Taking pseudo-random value from the previous block */
if (data_independent_addressing) {
if (i % ARGON2_ADDRESSES_IN_BLOCK == 0) {
next_addresses(&address_block, &input_block, &zero_block);
}
pseudo_rand = address_block.v[i % ARGON2_ADDRESSES_IN_BLOCK];
} else {
pseudo_rand = instance->memory[prev_offset].v[0];
}
/* 1.2.2 Computing the lane of the reference block */
ref_lane = ((pseudo_rand >> 32)) % instance->lanes;
if ((position.pass == 0) && (position.slice == 0)) {
/* Can not reference other lanes yet */
ref_lane = position.lane;
}
/* 1.2.3 Computing the number of possible reference block within the
* lane.
*/
position.index = i;
ref_index = index_alpha(instance, &position, pseudo_rand & 0xFFFFFFFF,
ref_lane == position.lane);
/* 2 Creating a new block */
ref_block =
instance->memory + instance->lane_length * ref_lane + ref_index;
curr_block = instance->memory + curr_offset;
if (ARGON2_VERSION_10 == instance->version) {
/* version 1.2.1 and earlier: overwrite, not XOR */
fill_block(instance->memory + prev_offset, ref_block, curr_block, 0);
} else {
if(0 == position.pass) {
fill_block(instance->memory + prev_offset, ref_block,
curr_block, 0);
} else {
fill_block(instance->memory + prev_offset, ref_block,
curr_block, 1);
}
}
}
}
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