/***********************************************************************************
* @fn halRfReadRxBufSecure
*
* @brief Decrypts and reverse authenticates with CCM then reads out received
* frame
*
* @param uint8* data - data buffer. This must be allocated by caller.
* uint8 length - number of bytes
* uint8 encrLength - number of bytes to decrypt
* uint8 authLength - number of bytes to reverse authenticate
* uuint8 m - integrity code (m=1,2,3 gives lenght of integrity
* field 4,8,16)
*
* @return HAL_RF_SUCCESS or HAL_RF_FAILED
*/
uint8 halRfReadRxBufSecure(uint8* data, uint8 length, uint8 encrLength, \
uint8 authLength, uint8 m)
{
uint8 dpuStat;
CC2520_RXBUFMOV(HIGH_PRIORITY, ADDR_RX, length, NULL);
WAIT_DPU_DONE_H();
// Find Framecounter value in received packet starting from 10th byte
// Copy in to nonce bytes (3-6) frame counter bytes
// Incoming frame uses nonce Rx
CC2520_MEMCP(HIGH_PRIORITY, 4, ADDR_RX+10, ADDR_NONCE_RX+3);
WAIT_DPU_DONE_H();
// Copy in short address to nonce bytes (7-8)
CC2520_MEMCP(HIGH_PRIORITY, 2, ADDR_RX+7, ADDR_NONCE_RX+7);
WAIT_DPU_DONE_H();
// Perform decryption and authentication
CC2520_UCCM(HIGH_PRIORITY,ADDR_KEY/16, encrLength, ADDR_NONCE_RX/16, ADDR_RX, ADDR_RX+authLength, authLength, m);
WAIT_DPU_DONE_H();
// Check authentication status
dpuStat = CC2520_REGRD8(CC2520_DPUSTAT);
// Read from RX work buffer into data buffer
CC2520_MEMRD(ADDR_RX, length, data);
if( (dpuStat & AUTHSTAT_H_BM) != AUTHSTAT_H_BM ) {
// Authentication failed
return HAL_RF_FAILED;
} else {
return HAL_RF_SUCCESS;
}
}
/***********************************************************************************
* @fn halRfReadMemory
*
* @brief Read RF device memory
*
* @param uint16 addr - memory address
* uint8* pData - data buffer. This must be allocated by caller.
* uint8 length - number of bytes
*
* @return Number of bytes read
*/
uint8 halRfReadMemory(uint16 addr, uint8* pData, uint8 length)
{
if (addr>=CC2520_MEMORY_SIZE)
length= 0;
else if (addr+length>CC2520_MEMORY_SIZE)
length= CC2520_MEMORY_SIZE - addr;
CC2520_MEMRD(addr, length, pData);
return length;
}
