Hii nordic;
I need to encrypt and decrypt my advertising data i.e;UUID,Major,Minor,etc.; of my nrf52832
So it cannot be seen by third parties
my sdk version is 15.2 and softdevice is 132
Hii nordic;
I need to encrypt and decrypt my advertising data i.e;UUID,Major,Minor,etc.; of my nrf52832
So it cannot be seen by third parties
my sdk version is 15.2 and softdevice is 132
Hi Naralasetty and Shivali,
I apologize for the very late reply.
I have modified the decryption_central project's main.c file to extract the nounce from the scan response packet and extract the beacon info from the advertisment packet. It then calls ctr_init() to update the nounce and then calls ctr_decrypt on the extracted beacon data. the main file is attached:
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include "nordic_common.h"
#include "app_error.h"
#include "app_uart.h"
#include "ble_db_discovery.h"
#include "app_timer.h"
#include "app_util.h"
#include "bsp_btn_ble.h"
#include "ble.h"
#include "ble_gap.h"
#include "ble_hci.h"
#include "nrf_sdh.h"
#include "nrf_sdh_ble.h"
#include "nrf_sdh_soc.h"
#include "ble_nus_c.h"
#include "nrf_ble_gatt.h"
#include "nrf_pwr_mgmt.h"
#include "nrf_ble_scan.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
#include "nrf_delay.h"
#include "ble_srv_common.h"
#include "ble_advdata.h"
#define APP_BLE_CONN_CFG_TAG 1 /**< Tag that refers to the BLE stack configuration set with @ref sd_ble_cfg_set. The default tag is @ref BLE_CONN_CFG_TAG_DEFAULT. */
#define APP_BLE_OBSERVER_PRIO 3 /**< BLE observer priority of the application. There is no need to modify this value. */
#define UART_TX_BUF_SIZE 256 /**< UART TX buffer size. */
#define UART_RX_BUF_SIZE 256 /**< UART RX buffer size. */
#define NUS_SERVICE_UUID_TYPE BLE_UUID_TYPE_VENDOR_BEGIN /**< UUID type for the Nordic UART Service (vendor specific). */
#define ECHOBACK_BLE_UART_DATA 1 /**< Echo the UART data that is received over the Nordic UART Service (NUS) back to the sender. */
#define ECB_KEY_LEN (16UL)
#define COUNTER_BYTE_LEN (4UL)
#define NONCE_RAND_BYTE_LEN (12UL)
// The RNG wait values are typical and not guaranteed. See Product Specifications for more info.
#ifdef NRF51
#define RNG_BYTE_WAIT_US (677UL)
#elif defined NRF52
#define RNG_BYTE_WAIT_US (124UL)
#else
#error "Either NRF51 or NRF52 must be defined."
#endif
BLE_NUS_C_DEF(m_ble_nus_c); /**< BLE Nordic UART Service (NUS) client instance. */
NRF_BLE_GATT_DEF(m_gatt); /**< GATT module instance. */
BLE_DB_DISCOVERY_DEF(m_db_disc); /**< Database discovery module instance. */
NRF_BLE_SCAN_DEF(m_scan); /**< Scanning Module instance. */
static uint16_t m_ble_nus_max_data_len = BLE_GATT_ATT_MTU_DEFAULT - OPCODE_LENGTH - HANDLE_LENGTH; /**< Maximum length of data (in bytes) that can be transmitted to the peer by the Nordic UART service module. */
static bool m_initialized = false;
static nrf_ecb_hal_data_t m_ecb_data;
static uint8_t m_ecb_key[16] = {0x6E,0x88,0x90,0x8D,0x75,0xBB,0x95,0xEA,0x2C,0x65,0x93,0x01,0x43,0xF8,0x1B,0x5F};
static uint8_t nounce[16];
static uint8_t m_beacon_info[0x17];
/**@brief NUS UUID. */
static ble_uuid_t const m_nus_uuid =
{
.uuid = BLE_UUID_IMMEDIATE_ALERT_SERVICE,
.type = BLE_UUID_TYPE_BLE
};
void assert_nrf_callback(uint16_t line_num, const uint8_t * p_file_name)
{
app_error_handler(0xDEADBEEF, line_num, p_file_name);
}
void ctr_init(const uint8_t * p_nonce, const uint8_t * p_ecb_key)
{
m_initialized = true;
// Save the key.
memcpy(&m_ecb_data.key[0], p_ecb_key, ECB_KEY_LEN);
// Copy the nonce.
memcpy(&m_ecb_data.ciphertext[COUNTER_BYTE_LEN],
&p_nonce[COUNTER_BYTE_LEN],
NONCE_RAND_BYTE_LEN);
// Zero the counter value.
memset(&m_ecb_data.cleartext[0], 0x00, COUNTER_BYTE_LEN);
}
static uint32_t crypt(uint8_t * buf)
{
uint8_t i;
uint32_t err_code;
if (!m_initialized)
{
return NRF_ERROR_INVALID_STATE;
}
err_code = sd_ecb_block_encrypt(&m_ecb_data);
if (NRF_SUCCESS != err_code)
{
return err_code;
}
for (i=0; i < ECB_KEY_LEN; i++)
{
buf[i] ^= m_ecb_data.ciphertext[i];
}
// Increment the counter.
(*((uint32_t*) m_ecb_data.cleartext))++;
return NRF_SUCCESS;
}
uint32_t ctr_encrypt(uint8_t * p_clear_text)
{
return crypt(p_clear_text);
}
uint32_t ctr_decrypt(uint8_t * p_cipher_text)
{
return crypt(p_cipher_text);
}
/**@brief Function for starting scanning. */
static void scan_start(void)
{
ret_code_t ret;
ret = nrf_ble_scan_start(&m_scan);
APP_ERROR_CHECK(ret);
ret = bsp_indication_set(BSP_INDICATE_SCANNING);
APP_ERROR_CHECK(ret);
}
/**@brief Function for handling Scanning Module events.
*/
static void scan_evt_handler(scan_evt_t const * p_scan_evt)
{
ret_code_t err_code;
switch(p_scan_evt->scan_evt_id)
{
case NRF_BLE_SCAN_EVT_CONNECTING_ERROR:
{
err_code = p_scan_evt->params.connecting_err.err_code;
APP_ERROR_CHECK(err_code);
} break;
case NRF_BLE_SCAN_EVT_CONNECTED:
{
ble_gap_evt_connected_t const * p_connected =
p_scan_evt->params.connected.p_connected;
// Scan is automatically stopped by the connection.
NRF_LOG_INFO("Connecting to target %02x%02x%02x%02x%02x%02x",
p_connected->peer_addr.addr[0],
p_connected->peer_addr.addr[1],
p_connected->peer_addr.addr[2],
p_connected->peer_addr.addr[3],
p_connected->peer_addr.addr[4],
p_connected->peer_addr.addr[5]
);
} break;
case NRF_BLE_SCAN_EVT_SCAN_TIMEOUT:
{
NRF_LOG_INFO("Scan timed out.");
scan_start();
} break;
case NRF_BLE_SCAN_EVT_SCAN_REQ_REPORT:
{
NRF_LOG_INFO("Scan Request Report received!");
break;
}
case NRF_BLE_SCAN_EVT_FILTER_MATCH:
{
NRF_LOG_INFO("Received Advertisment Report that matches the scan filter(s)!");
break;
}
default:
break;
}
}
/**@brief Function for initializing the scanning and setting the filters.
*/
static void scan_init(void)
{
ret_code_t err_code;
nrf_ble_scan_init_t init_scan;
ble_gap_scan_params_t scan_params;
memset(&scan_params,0,sizeof(scan_params));
scan_params.active = 1;
scan_params.interval = NRF_BLE_SCAN_SCAN_INTERVAL;
scan_params.window = NRF_BLE_SCAN_SCAN_WINDOW;
scan_params.timeout = 0;
scan_params.filter_policy = BLE_GAP_SCAN_FP_ACCEPT_ALL;
scan_params.scan_phys = BLE_GAP_PHY_1MBPS;
//scan_params.report_incomplete_evts = true;
memset(&init_scan, 0, sizeof(init_scan));
init_scan.connect_if_match = false;
init_scan.conn_cfg_tag = APP_BLE_CONN_CFG_TAG;
init_scan.p_scan_param = &scan_params;
err_code = nrf_ble_scan_init(&m_scan, &init_scan, scan_evt_handler);
APP_ERROR_CHECK(err_code);
/*
err_code = nrf_ble_scan_filter_set(&m_scan, SCAN_UUID_FILTER, &m_nus_uuid);
APP_ERROR_CHECK(err_code);
err_code = nrf_ble_scan_filters_enable(&m_scan, NRF_BLE_SCAN_UUID_FILTER, false);
APP_ERROR_CHECK(err_code);
*/
}
static void db_disc_handler(ble_db_discovery_evt_t * p_evt)
{
ble_nus_c_on_db_disc_evt(&m_ble_nus_c, p_evt);
}
static void ble_nus_chars_received_uart_print(uint8_t * p_data, uint16_t data_len)
{
ret_code_t ret_val;
NRF_LOG_DEBUG("Receiving data.");
NRF_LOG_HEXDUMP_DEBUG(p_data, data_len);
for (uint32_t i = 0; i < data_len; i++)
{
do
{
ret_val = app_uart_put(p_data[i]);
if ((ret_val != NRF_SUCCESS) && (ret_val != NRF_ERROR_BUSY))
{
NRF_LOG_ERROR("app_uart_put failed for index 0x%04x.", i);
APP_ERROR_CHECK(ret_val);
}
} while (ret_val == NRF_ERROR_BUSY);
}
if (p_data[data_len-1] == '\r')
{
while (app_uart_put('\n') == NRF_ERROR_BUSY);
}
if (ECHOBACK_BLE_UART_DATA)
{
// Send data back to the peripheral.
do
{
ret_val = ble_nus_c_string_send(&m_ble_nus_c, p_data, data_len);
if ((ret_val != NRF_SUCCESS) && (ret_val != NRF_ERROR_BUSY))
{
NRF_LOG_ERROR("Failed sending NUS message. Error 0x%x. ", ret_val);
APP_ERROR_CHECK(ret_val);
}
} while (ret_val == NRF_ERROR_BUSY);
}
}
void uart_event_handle(app_uart_evt_t * p_event)
{
static uint8_t data_array[BLE_NUS_MAX_DATA_LEN];
static uint16_t index = 0;
uint32_t ret_val;
switch (p_event->evt_type)
{
/**@snippet [Handling data from UART] */
case APP_UART_DATA_READY:
UNUSED_VARIABLE(app_uart_get(&data_array[index]));
index++;
if ((data_array[index - 1] == '\n') || (index >= (m_ble_nus_max_data_len)))
{
NRF_LOG_DEBUG("Ready to send data over BLE NUS");
NRF_LOG_HEXDUMP_DEBUG(data_array, index);
do
{
ret_val = ble_nus_c_string_send(&m_ble_nus_c, data_array, index);
if ( (ret_val != NRF_ERROR_INVALID_STATE) && (ret_val != NRF_ERROR_RESOURCES) )
{
APP_ERROR_CHECK(ret_val);
}
} while (ret_val == NRF_ERROR_RESOURCES);
index = 0;
}
break;
/**@snippet [Handling data from UART] */
case APP_UART_COMMUNICATION_ERROR:
NRF_LOG_ERROR("Communication error occurred while handling UART.");
APP_ERROR_HANDLER(p_event->data.error_communication);
break;
case APP_UART_FIFO_ERROR:
NRF_LOG_ERROR("Error occurred in FIFO module used by UART.");
APP_ERROR_HANDLER(p_event->data.error_code);
break;
default:
break;
}
}
/**@snippet [Handling events from the ble_nus_c module] */
static void ble_nus_c_evt_handler(ble_nus_c_t * p_ble_nus_c, ble_nus_c_evt_t const * p_ble_nus_evt)
{
ret_code_t err_code;
switch (p_ble_nus_evt->evt_type)
{
case BLE_NUS_C_EVT_DISCOVERY_COMPLETE:
NRF_LOG_INFO("Discovery complete.");
err_code = ble_nus_c_handles_assign(p_ble_nus_c, p_ble_nus_evt->conn_handle, &p_ble_nus_evt->handles);
APP_ERROR_CHECK(err_code);
err_code = ble_nus_c_tx_notif_enable(p_ble_nus_c);
APP_ERROR_CHECK(err_code);
NRF_LOG_INFO("Connected to device with Nordic UART Service.");
break;
case BLE_NUS_C_EVT_NUS_TX_EVT:
ble_nus_chars_received_uart_print(p_ble_nus_evt->p_data, p_ble_nus_evt->data_len);
break;
case BLE_NUS_C_EVT_DISCONNECTED:
NRF_LOG_INFO("Disconnected.");
scan_start();
break;
}
}
/**@snippet [Handling events from the ble_nus_c module] */
/**
* @brief Function for handling shutdown events.
*
* @param[in] event Shutdown type.
*/
static bool shutdown_handler(nrf_pwr_mgmt_evt_t event)
{
ret_code_t err_code;
err_code = bsp_indication_set(BSP_INDICATE_IDLE);
APP_ERROR_CHECK(err_code);
switch (event)
{
case NRF_PWR_MGMT_EVT_PREPARE_WAKEUP:
// Prepare wakeup buttons.
err_code = bsp_btn_ble_sleep_mode_prepare();
APP_ERROR_CHECK(err_code);
break;
default:
break;
}
return true;
}
NRF_PWR_MGMT_HANDLER_REGISTER(shutdown_handler, APP_SHUTDOWN_HANDLER_PRIORITY);
/**@brief Function for handling BLE events.
*
* @param[in] p_ble_evt Bluetooth stack event.
* @param[in] p_context Unused.
*/
static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)
{
ret_code_t err_code;
ble_gap_evt_t const * p_gap_evt = &p_ble_evt->evt.gap_evt;
uint8_t uuid[26];
switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_CONNECTED:
err_code = ble_nus_c_handles_assign(&m_ble_nus_c, p_ble_evt->evt.gap_evt.conn_handle, NULL);
APP_ERROR_CHECK(err_code);
err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);
APP_ERROR_CHECK(err_code);
// start discovery of services. The NUS Client waits for a discovery result
err_code = ble_db_discovery_start(&m_db_disc, p_ble_evt->evt.gap_evt.conn_handle);
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_DISCONNECTED:
NRF_LOG_INFO("Disconnected. conn_handle: 0x%x, reason: 0x%x",
p_gap_evt->conn_handle,
p_gap_evt->params.disconnected.reason);
break;
case BLE_GAP_EVT_TIMEOUT:
if (p_gap_evt->params.timeout.src == BLE_GAP_TIMEOUT_SRC_CONN)
{
NRF_LOG_INFO("Connection Request timed out.");
}
break;
case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
// Pairing not supported.
err_code = sd_ble_gap_sec_params_reply(p_ble_evt->evt.gap_evt.conn_handle, BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP, NULL, NULL);
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST:
// Accepting parameters requested by peer.
err_code = sd_ble_gap_conn_param_update(p_gap_evt->conn_handle,
&p_gap_evt->params.conn_param_update_request.conn_params);
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
{
NRF_LOG_DEBUG("PHY update request.");
ble_gap_phys_t const phys =
{
.rx_phys = BLE_GAP_PHY_AUTO,
.tx_phys = BLE_GAP_PHY_AUTO,
};
err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
APP_ERROR_CHECK(err_code);
} break;
case BLE_GATTC_EVT_TIMEOUT:
// Disconnect on GATT Client timeout event.
NRF_LOG_DEBUG("GATT Client Timeout.");
err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
APP_ERROR_CHECK(err_code);
break;
case BLE_GATTS_EVT_TIMEOUT:
// Disconnect on GATT Server timeout event.
NRF_LOG_DEBUG("GATT Server Timeout.");
err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_ADV_REPORT:
{
//NRF_LOG_INFO("Advertise received");
scan_start();
/*//nrf_gpio_pin_toggle(LED1_PIN);
NRF_LOG_INFO("Scannable: %d",p_gap_evt->params.adv_report.type.scannable);
NRF_LOG_INFO("Scan-response: %d",p_gap_evt->params.adv_report.type.scan_response);
*/
ble_gap_addr_t addr;
memcpy(addr.addr, p_gap_evt->params.adv_report.peer_addr.addr, 6);
/* NRF_LOG_INFO("Beacon address: %02x:%02x:%02x:%02x:%02x:%02x",
p_gap_evt->params.adv_report.peer_addr.addr[5],
p_gap_evt->params.adv_report.peer_addr.addr[4],
p_gap_evt->params.adv_report.peer_addr.addr[3],
p_gap_evt->params.adv_report.peer_addr.addr[2],
p_gap_evt->params.adv_report.peer_addr.addr[1],
p_gap_evt->params.adv_report.peer_addr.addr[0]);
*/
// Filter on peripheral address. Should iterate over a list of known peripherals.
uint8_t beacon_addr[6] ={0xec,0x97,0x40,0x5b,0xaf,0xfa};
if(!memcmp(addr.addr,beacon_addr, sizeof(beacon_addr))){
//NRF_LOG_INFO("Scannable: %d",p_gap_evt->params.adv_report.type.scan_response);
uint16_t data_offset = 0;
uint16_t maunf_data_len;
//Check if it is a scan response packet
if(p_gap_evt->params.adv_report.type.scan_response)
{
NRF_LOG_INFO("Scan response report received");
// Search for manuf data in the scan response packet
maunf_data_len = ble_advdata_search(p_gap_evt->params.adv_report.data.p_data, p_gap_evt->params.adv_report.data.len,&data_offset,BLE_GAP_AD_TYPE_MANUFACTURER_SPECIFIC_DATA);
NRF_LOG_HEXDUMP_INFO((p_gap_evt->params.adv_report.data.p_data+data_offset),maunf_data_len);
// Extract nounce
memcpy(nounce,p_gap_evt->params.adv_report.data.p_data+data_offset,maunf_data_len);
// Intialize the crypto module
ctr_init(nounce,m_ecb_key);
}
else
{
// Find the manuf data in the advertisment packet
maunf_data_len = ble_advdata_search(p_gap_evt->params.adv_report.data.p_data, p_gap_evt->params.adv_report.data.len,&data_offset,BLE_GAP_AD_TYPE_MANUFACTURER_SPECIFIC_DATA);
NRF_LOG_HEXDUMP_INFO((p_gap_evt->params.adv_report.data.p_data+data_offset),maunf_data_len);
// Copy manuf data to beacon info array
memcpy(m_beacon_info,p_gap_evt->params.adv_report.data.p_data+data_offset,maunf_data_len);
// Decrypt the advertisment manuf data
ctr_decrypt(m_beacon_info);
ctr_decrypt(&m_beacon_info[16]);
NRF_LOG_INFO("Decrypted info:");
NRF_LOG_HEXDUMP_INFO(m_beacon_info, sizeof(m_beacon_info));
// Reset counter values for next decrypt
m_ecb_data.cleartext[0] = 0x00;
m_ecb_data.cleartext[1] = 0x00;
m_ecb_data.cleartext[2] = 0x00;
m_ecb_data.cleartext[3] = 0x00;
memmove(uuid, p_gap_evt->params.adv_report.data.p_data, p_gap_evt->params.adv_report.data.len);
NRF_LOG_INFO("UUID: %02x%02x%02x%02x%02x%02x", uuid[9], uuid[10], uuid[11], uuid[12], uuid[13], uuid[14]);
NRF_LOG_INFO("TX_POWER: %02x", p_gap_evt->params.adv_report.tx_power);
NRF_LOG_INFO("RSSI: %02x", p_gap_evt->params.adv_report.rssi);
}
// uint8_t batt_lvl;
// NRF_LOG_INFO("battery level: %02x", p_gap_evt->params.adv_report.batt_lvl);
}
} break;
case BLE_GAP_EVT_SCAN_REQ_REPORT:
NRF_LOG_INFO("Scan response report received");
break;
default:
break;
}
}
/**@brief Function for initializing the BLE stack.
*
* @details Initializes the SoftDevice and the BLE event interrupt.
*/
static void ble_stack_init(void)
{
ret_code_t err_code;
err_code = nrf_sdh_enable_request();
APP_ERROR_CHECK(err_code);
// Configure the BLE stack using the default settings.
// Fetch the start address of the application RAM.
uint32_t ram_start = 0;
err_code = nrf_sdh_ble_default_cfg_set(APP_BLE_CONN_CFG_TAG, &ram_start);
APP_ERROR_CHECK(err_code);
// Enable BLE stack.
err_code = nrf_sdh_ble_enable(&ram_start);
APP_ERROR_CHECK(err_code);
// Register a handler for BLE events.
NRF_SDH_BLE_OBSERVER(m_ble_observer, APP_BLE_OBSERVER_PRIO, ble_evt_handler, NULL);
}
/**@brief Function for handling events from the GATT library. */
void gatt_evt_handler(nrf_ble_gatt_t * p_gatt, nrf_ble_gatt_evt_t const * p_evt)
{
if (p_evt->evt_id == NRF_BLE_GATT_EVT_ATT_MTU_UPDATED)
{
NRF_LOG_INFO("ATT MTU exchange completed.");
m_ble_nus_max_data_len = p_evt->params.att_mtu_effective - OPCODE_LENGTH - HANDLE_LENGTH;
NRF_LOG_INFO("Ble NUS max data length set to 0x%X(%d)", m_ble_nus_max_data_len, m_ble_nus_max_data_len);
}
}
/**@brief Function for initializing the GATT library. */
void gatt_init(void)
{
ret_code_t err_code;
err_code = nrf_ble_gatt_init(&m_gatt, gatt_evt_handler);
APP_ERROR_CHECK(err_code);
err_code = nrf_ble_gatt_att_mtu_central_set(&m_gatt, NRF_SDH_BLE_GATT_MAX_MTU_SIZE);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling events from the BSP module.
*
* @param[in] event Event generated by button press.
*/
void bsp_event_handler(bsp_event_t event)
{
ret_code_t err_code;
switch (event)
{
case BSP_EVENT_SLEEP:
nrf_pwr_mgmt_shutdown(NRF_PWR_MGMT_SHUTDOWN_GOTO_SYSOFF);
break;
case BSP_EVENT_DISCONNECT:
err_code = sd_ble_gap_disconnect(m_ble_nus_c.conn_handle,
BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
if (err_code != NRF_ERROR_INVALID_STATE)
{
APP_ERROR_CHECK(err_code);
}
break;
default:
break;
}
}
/**@brief Function for initializing the UART. */
static void uart_init(void)
{
ret_code_t err_code;
app_uart_comm_params_t const comm_params =
{
.rx_pin_no = RX_PIN_NUMBER,
.tx_pin_no = TX_PIN_NUMBER,
.rts_pin_no = RTS_PIN_NUMBER,
.cts_pin_no = CTS_PIN_NUMBER,
.flow_control = APP_UART_FLOW_CONTROL_DISABLED,
.use_parity = false,
.baud_rate = UART_BAUDRATE_BAUDRATE_Baud115200
};
APP_UART_FIFO_INIT(&comm_params,
UART_RX_BUF_SIZE,
UART_TX_BUF_SIZE,
uart_event_handle,
APP_IRQ_PRIORITY_LOWEST,
err_code);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the Nordic UART Service (NUS) client. */
static void nus_c_init(void)
{
ret_code_t err_code;
ble_nus_c_init_t init;
init.evt_handler = ble_nus_c_evt_handler;
err_code = ble_nus_c_init(&m_ble_nus_c, &init);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing buttons and leds. */
static void buttons_leds_init(void)
{
ret_code_t err_code;
bsp_event_t startup_event;
err_code = bsp_init(BSP_INIT_LEDS, bsp_event_handler);
APP_ERROR_CHECK(err_code);
err_code = bsp_btn_ble_init(NULL, &startup_event);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the timer. */
static void timer_init(void)
{
ret_code_t err_code = app_timer_init();
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the nrf log module. */
static void log_init(void)
{
ret_code_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
}
/**@brief Function for initializing power management.
*/
static void power_management_init(void)
{
ret_code_t err_code;
err_code = nrf_pwr_mgmt_init();
APP_ERROR_CHECK(err_code);
}
/** @brief Function for initializing the database discovery module. */
static void db_discovery_init(void)
{
ret_code_t err_code = ble_db_discovery_init(db_disc_handler);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling the idle state (main loop).
*
* @details Handles any pending log operations, then sleeps until the next event occurs.
*/
static void idle_state_handle(void)
{
if (NRF_LOG_PROCESS() == false)
{
nrf_pwr_mgmt_run();
}
}
void nonce_generate(uint8_t * p_buf)
{
uint8_t i = COUNTER_BYTE_LEN;
uint8_t remaining = NONCE_RAND_BYTE_LEN;
while(0 != remaining)
{
uint32_t err_code;
uint8_t available = 0;
err_code = sd_rand_application_bytes_available_get(&available);
APP_ERROR_CHECK(err_code);
available = ((available > remaining) ? remaining : available);
if (0 != available)
{
err_code = sd_rand_application_vector_get((p_buf + i), available);
APP_ERROR_CHECK(err_code);
i += available;
remaining -= available;
}
if (0 != remaining)
{
nrf_delay_us(RNG_BYTE_WAIT_US * remaining);
}
}
}
int main(void)
{
uint32_t err_code;
// Initialize.
log_init();
timer_init();
uart_init();
buttons_leds_init();
db_discovery_init();
power_management_init();
ble_stack_init();
gatt_init();
nus_c_init();
scan_init();
printf("BLE UART central example started.\r\n");
NRF_LOG_INFO("BLE UART central example started.");
scan_start();
ble_gap_addr_t gap_address;
err_code = sd_ble_gap_addr_get(&gap_address);
APP_ERROR_CHECK(err_code);
NRF_LOG_HEXDUMP_INFO(&gap_address.addr,sizeof(gap_address.addr));
uint8_t nonce[16] = {0};
uint8_t m_beacon_info[16];
ctr_init(nonce,m_ecb_key);
NRF_LOG_INFO("Encrypted info:");
NRF_LOG_HEXDUMP_INFO(m_beacon_info, sizeof(m_beacon_info));
m_ecb_data.cleartext[0] = 0x00;
m_ecb_data.cleartext[1] = 0x00;
m_ecb_data.cleartext[2] = 0x00;
m_ecb_data.cleartext[3] = 0x00;
// Decrypt the ciphertext with the same counter value, i.e. 0x00,0x00,0x00,0x00, that was used for encrypting.
ctr_decrypt(m_beacon_info);
ctr_decrypt(&m_beacon_info[16]);
NRF_LOG_INFO("Decrypted info:");
NRF_LOG_HEXDUMP_INFO(m_beacon_info, sizeof(m_beacon_info));
// Start execution.
// Enter main loop.
for (;;)
{
idle_state_handle();
}
}
Best regards
Bjørn
Hi Bjorn, would like to know what's the different calling
ctr_encrypt(m_beacon_info);
ctr_encrypt(&m_beacon_info[16]);
we necessary have to do this twice to encrypt ?
Thank you.
Regards,
Kathleen
Hi,
Can you please tell why are you using ctr_decrypt() function twice for the same data in the above code?
ctr_decrypt(m_beacon_info); ctr_decrypt(&m_beacon_info[16]);
And is it necessary to add " case BLE_GAP_EVT_ADV_REPORT: " within