//generate 6 different functions and store in memory void generateRoundFunctions(unsigned char * seed, unsigned int * bufint, int blocks) { int err; int i=0; int j=0; unsigned char buf[4]; //bufint = malloc(blocks*sizeof(unsigned int)); int index = 0; prng_state prng; if ((err = fortuna_start(&prng)) != CRYPT_OK) { printf("start error: %s\n", error_to_string(err)); } if ((err = fortuna_add_entropy(seed, strlen(seed), &prng))!= CRYPT_OK) { printf("Add entropy error: %s\n", error_to_string(err)); } if ((err = fortuna_ready(&prng)) != CRYPT_OK) { printf("Ready error: %s\n", error_to_string(err)); } for(i=0;i<blocks;i++){ fortuna_read(buf,sizeof(buf),&prng); bufint[i] = *(unsigned int *)buf; } }
static int sqlcipher_ltc_activate(void *ctx) { ltc_ctx *ltc = (ltc_ctx*)ctx; int random_buffer_sz = 32; unsigned char random_buffer[random_buffer_sz]; if(ltc_init == 0) { if(register_prng(&fortuna_desc) != CRYPT_OK) return SQLITE_ERROR; if(register_cipher(&rijndael_desc) != CRYPT_OK) return SQLITE_ERROR; if(register_hash(&sha1_desc) != CRYPT_OK) return SQLITE_ERROR; ltc_init = 1; } if(fortuna_start(&(ltc->prng)) != CRYPT_OK) { return SQLITE_ERROR; } sqlite3_randomness(random_buffer_sz, &random_buffer); if(sqlcipher_ltc_add_random(ctx, random_buffer, random_buffer_sz) != SQLITE_OK) { return SQLITE_ERROR; } if(sqlcipher_ltc_add_random(ctx, <c, sizeof(ltc_ctx*)) != SQLITE_OK) { return SQLITE_ERROR; } if(fortuna_ready(&(ltc->prng)) != CRYPT_OK) { return SQLITE_ERROR; } return SQLITE_OK; }
static int sqlcipher_ltc_random(void *ctx, void *buffer, int length) { ltc_ctx *ltc = (ltc_ctx*)ctx; int rc; if((rc = fortuna_ready(&(ltc->prng))) != CRYPT_OK) { return SQLITE_ERROR; } fortuna_read(buffer, length, &(ltc->prng)); return SQLITE_OK; }
static int sqlcipher_ltc_add_random(void *ctx, void *buffer, int length) { int rc = 0; int data_to_read = length; int block_sz = data_to_read < FORTUNA_MAX_SZ ? data_to_read : FORTUNA_MAX_SZ; const unsigned char * data = (const unsigned char *)buffer; #ifndef SQLCIPHER_LTC_NO_MUTEX_RAND sqlite3_mutex_enter(ltc_rand_mutex); #endif while(data_to_read > 0){ rc = fortuna_add_entropy(data, block_sz, &prng); rc = rc != CRYPT_OK ? SQLITE_ERROR : SQLITE_OK; if(rc != SQLITE_OK){ break; } data_to_read -= block_sz; data += block_sz; block_sz = data_to_read < FORTUNA_MAX_SZ ? data_to_read : FORTUNA_MAX_SZ; } fortuna_ready(&prng); #ifndef SQLCIPHER_LTC_NO_MUTEX_RAND sqlite3_mutex_leave(ltc_rand_mutex); #endif return rc; }