struct octet_buffer get_otp_zone (fd)
{
const unsigned int SIZE_OF_OTP_ZONE = 64;
const unsigned int SIZE_OF_READ = 32;
const unsigned int SIZE_OF_WORD = 4;
const unsigned int SECOND_WORD = (SIZE_OF_READ / SIZE_OF_WORD);
struct octet_buffer buf = make_buffer (SIZE_OF_OTP_ZONE);
struct octet_buffer half;
int x = 0;
for (x=0; x < 2; x++ )
{
int addr = x * SECOND_WORD;
int offset = x * SIZE_OF_READ;
half = read32 (fd, OTP_ZONE, addr);
if (NULL != half.ptr)
{
memcpy (buf.ptr + offset, half.ptr, SIZE_OF_READ);
free_octet_buffer (half);
}
else
{
free_octet_buffer (buf);
buf.ptr = NULL;
return buf;
}
}
return buf;
}
struct octet_buffer get_check_mac_meta_data (int fd, struct mac_mode_encoding m,
unsigned int data_slot)
{
const unsigned int DLEN = 13;
struct octet_buffer result = make_buffer (DLEN);
uint8_t *p = result.ptr;
*p++ = COMMAND_MAC;
*p++ = serialize_mac_mode (m);
*p++ = data_slot;
*p++ = 0;
struct octet_buffer otp_zone = get_otp_zone (fd);
struct octet_buffer serial = get_serial_num (fd);
if (!m.use_serial_num)
{
unsigned int len = serial.len;
free_octet_buffer (serial);
serial = make_buffer (len);
}
if (!m.use_otp_0_10)
{
unsigned int len = otp_zone.len;
free_octet_buffer (otp_zone);
otp_zone = make_buffer (len);
}
const unsigned int OTP_8_10_LEN = 3;
const unsigned int SN_4_7_LEN = 4;
const unsigned int SN_2_3_LEN = 2;
if (NULL != otp_zone.ptr && NULL != serial.ptr)
{
memcpy (p, &otp_zone.ptr[8], OTP_8_10_LEN);
p += OTP_8_10_LEN;
memcpy (p, &serial.ptr[4], SN_4_7_LEN);
p += SN_4_7_LEN;
memcpy (p, &serial.ptr[2], SN_2_3_LEN);
}
else
{
free_octet_buffer (result);
result.ptr = NULL;
}
free_octet_buffer (otp_zone);
free_octet_buffer (serial);
return result;
}
struct mac_response perform_mac (int fd, struct mac_mode_encoding m,
unsigned int data_slot,
struct octet_buffer challenge)
{
const unsigned int recv_len = 32;
struct mac_response rsp = {0};
rsp.status = false;
uint8_t param1 = serialize_mac_mode (m);
uint8_t param2[2] = {0};
assert (data_slot <= MAX_NUM_DATA_SLOTS);
if (!m.use_second_32_temp_key)
assert (NULL != challenge.ptr && recv_len == challenge.len);
/* Param 2 is guaranteed to be less than 15 (check above) */
param2[0] = data_slot;
param2[1] = 0;
rsp.mac = make_buffer (recv_len);
struct Command_ATSHA204 c = make_command ();
set_opcode (&c, COMMAND_MAC);
set_param1 (&c, param1);
set_param2 (&c, param2);
/* TODO Fix for situations not sending the challlenge */
set_data (&c, challenge.ptr, challenge.len);
set_execution_time (&c, 0, MAC_AVG_EXEC);
if (RSP_SUCCESS == process_command (fd, &c, rsp.mac.ptr, recv_len))
{
/* Perform a check mac to ensure we have the data correct */
rsp.meta = get_check_mac_meta_data (fd, m, data_slot);
struct check_mac_encoding cm = {0};
rsp.status = check_mac (fd, cm, data_slot, challenge, rsp.mac, rsp.meta);
}
else
{
free_octet_buffer (rsp.mac);
}
return rsp;
}
enum DEVICE_STATE personalize (int fd, enum DEVICE_STATE goal,
struct key_container *keys)
{
enum DEVICE_STATE state = get_device_state (fd);
if (state >= goal)
return state;
if (set_config_zone (fd) && lock_config_zone (fd, state))
{
state = STATE_INITIALIZED;
assert (get_device_state (fd) == state);
struct octet_buffer otp_zone;
if (set_otp_zone (fd, &otp_zone))
{
struct octet_buffer data_zone;
if (write_keys (fd, keys, &data_zone))
{
uint16_t crc = crc_data_otp_zone (data_zone, otp_zone);
if (lock (fd, DATA_ZONE, crc))
{
state = STATE_PERSONALIZED;
assert (get_device_state (fd) == state);
}
free_octet_buffer (data_zone);
}
free_octet_buffer (otp_zone);
}
}
return state;
}
void free_key_container (struct key_container *keys)
{
assert (NULL != keys);
unsigned int x = 0;
for (x=0; x < get_max_keys (); x++)
{
if (NULL != keys->keys[x].ptr)
free_octet_buffer (keys->keys[x]);
}
free (keys);
}