Node / markqvist / OpenModem.git / files / hardware / Crypto.c

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#include "Crypto.h"

uint8_t active_key[16];

uint8_t active_iv[16];

aes_128_context_t context;

uint8_t current_vector[16];

void crypto_init(void) {

crypto_test();

return;

}

void crypto_prepare(uint8_t key[16], uint8_t initialization_vector[16]) {

// Initialise the context with the key

aes_128_init(&context, key);

// Copy the IV into the current vector array

memcpy(current_vector, initialization_vector, 16);

}

void crypto_encrypt_block(uint8_t block[16]) {

int i;

// XOR the current vector with the block before encrypting

for (i = 0; i < 16; i++) {

block[i] ^= current_vector[i];

}

// Encrypt the block

aes_128_encrypt(&context, block);

// Copy the cipher output to the current vector

memcpy(current_vector, block, 16);

}

void crypto_decrypt_block(uint8_t block[16]) {

uint8_t temp_vector[16];

int i;

// Copy the cipher output to the temporary vector

memcpy(temp_vector, block, 16);

// Decrypt the block

aes_128_decrypt(&context, block);

// XOR the output with the current vector to fully decrypt

for (i = 0; i < 16; i++) {

block[i] ^= current_vector[i];

}

// Copy the temporary vector to the current vector

memcpy(current_vector, temp_vector, 16);

}

void load_key(void) {

// TODO: implement

}

void generate_iv(void) {

// TODO: implement

}

void crypto_test(void) {

}