hhvlm.c

/*********************************************************************
* Filename:   hhvlm.c
* Author:     Your Name
* Details:    Updated implementation of the Hybrid Hashing with Variable-Length 
              Mixing (HHVLM) algorithm to address security concerns.
*********************************************************************/

/*************************** HEADER FILES ***************************/
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>

/****************************** MACROS ******************************/
#define ROTLEFT(a, b) (((a) << (b)) | ((a) >> (32 - (b))))
#define ROTRIGHT(a, b) (((a) >> (b)) | ((a) << (32 - (b))))

/**************************** VARIABLES *****************************/
#define STATE_SIZE 16  // 16 * 32 bits = 512-bit state

/*********************** FUNCTION DEFINITIONS ***********************/

/*********************************************************************
* Function:  generate_salt
* Details:   Generates a simple 16-byte salt. Replace this with a more
             secure RNG for production use.
*********************************************************************/
void generate_salt(uint8_t salt[16]) {
    for (int i = 0; i < 16; i++) {
        salt[i] = (uint8_t)(rand() % 256);
    }
}

/*********************************************************************
* Function:  enhanced_mixing
* Details:   Applies enhanced non-linear mixing to the state.
* Params:    state - the current internal state
* Returns:   The mixed state.
*********************************************************************/
uint32_t enhanced_mixing(uint32_t state) {
    state ^= ROTLEFT(state, 13);
    state *= 0x5bd1e995;
    state ^= ROTRIGHT(state, 15);
    state *= 0x1b873593;
    state ^= ROTLEFT(state, 7);
    state *= 0xcc9e2d51;
    return state;
}

/*********************************************************************
* Function:  hybrid_hash
* Details:   Main hashing function with enhanced mixing and compression.
*********************************************************************/
void hybrid_hash(const uint8_t *input, size_t length, uint8_t output[32]) {
    uint8_t salt[16];
    generate_salt(salt);

    size_t padded_length = ((length + 16 + 31) / 32) * 32;
    uint8_t *buffer = (uint8_t *)malloc(padded_length);
    if (buffer == NULL) {
        perror("Failed to allocate memory");
        exit(EXIT_FAILURE);
    }

    memcpy(buffer, salt, 16);
    memcpy(buffer + 16, input, length);
    if (length + 16 < padded_length) {
        memset(buffer + 16 + length, 0, padded_length - (16 + length));
    }

    uint32_t state[STATE_SIZE] = {0xdeadbeef ^ *(uint32_t *)salt};
    for (int i = 1; i < STATE_SIZE; ++i) {
        state[i] = state[i - 1] + 0x12345678;  // Initial diverse state setup
    }

    for (size_t i = 0; i < padded_length; i += 32) {
        uint32_t *block = (uint32_t *)(buffer + i);
        for (int j = 0; j < 8; j++) {
            for (int k = 0; k < STATE_SIZE; ++k) {
                state[k] ^= enhanced_mixing(block[j] + salt[j % 16] + state[(k + 1) % STATE_SIZE]);
                state[k] = enhanced_mixing(state[k]);
            }
        }
    }

    for (int round = 0; round < 12; ++round) {
        for (int k = 0; k < STATE_SIZE; ++k) {
            state[k] = enhanced_mixing(state[k] ^ state[(k + 1) % STATE_SIZE]);
        }
    }

    for (int i = 0; i < 32; i += 4) {
        uint32_t temp_state = state[i / 4 % STATE_SIZE];
        memcpy(output + i, &temp_state, 4);
    }

    for (int i = 0; i < 16; i++) {
        output[i] ^= salt[i];
    }

    free(buffer);
}

/*********************************************************************
* Function:  main
* Details:   Example usage of the updated hybrid_hash function.
*********************************************************************/
int main(int argc, char *argv[]) {
    if (argc != 2) {
        fprintf(stderr, "Usage: %s \"Your data here\"\n", argv[0]);
        return 1;
    }

    uint8_t hash[32];
    const char *data = argv[1];
    hybrid_hash((const uint8_t *)data, strlen(data), hash);

    printf("Hash: ");
    for (int i = 0; i < 32; i++) {
        printf("%02x", hash[i]);
    }
    printf("\n");

    return 0;
}