Hello, quick update: I have now this function to set LE record with informations like flags, Random and Confirmation value, as well as TK (necessary for OOB Pairing in LE secure connections). This is my function:
int BLEHandler::SetOOBPairData(uint8_t *buffer, uint32_t length)
{
ndefTypeBluetooth bluetooth;
ndefRecord record;
ndefType ndefBt;
ndefStatus rc;
if (buffer == NULL)
return ERR_PARAM;
/* Reset bluetooth record */
rc = ndefBluetoothReset(&bluetooth);
if (rc != ERR_NONE)
return rc;
/* Get bluetooth informations - Address, Address Type, Random and Confirm value */
rc = bt_le_oob_get_local(0, &oob_data);
/* Mandatory field: bufDeviceAddress - Device Address (only for BR/EDR) */
ndefConstBuffer bufDeviceAddress = { (uint8_t *) oob_data.addr.a.val, 6 };
bluetooth.bufDeviceAddress = bufDeviceAddress;
/* Optional fields: Extended Inquiry Responses. Up to 8 data structures
* According to BLE spec, the data format should be: Length, EIR Data Type, EIR Data
*/
/* EIR Field 0: LE Flags */
uint8_t eirLeFlags[3] = { 2, NDEF_BT_EIR_FLAGS, 0x02 };
/* EIR Field 1: LE Device Address - 6 LSB bytes: Device address, 7th byte: Address type (Public/Random) */
uint8_t eirLeAddress[9] = { 8, NDEF_BT_EIR_LE_DEVICE_ADDRESS };
memcpy(&eirLeAddress[2], oob_data.addr.a.val, 6);
eirLeAddress[8] = oob_data.addr.type;
/* EIR Field 2: LE Role - Peripheral */
uint8_t eirLeRole[] = { 2, NDEF_BT_EIR_LE_ROLE, NDEF_BLE_ROLE_PERIPH_ONLY };
/* EIR Field 3: Device local name */
uint8_t localName[] = { 'C', 'C', 'C', '_', 'D', 'K' };
uint8_t eirLocalName[8] = { 1 + sizeof(localName), NDEF_BT_EIR_COMPLETE_LOCAL_NAME };
memcpy(&eirLocalName[2], localName, sizeof(localName));
/* EIR Field 4: Temporary Key (TK) for secure pairing */
/* Generate random TK */
uint8_t tk[16];
rc = bt_rand(tk, 16);
if(rc)
Log("Error generating TK value\n");
uint8_t eirTk[18] = { 17, NDEF_BT_EIR_SECURITY_MANAGER_TK_VALUE };
memcpy(&eirTk[2], tk, sizeof(tk)); // Append the TK value after the length
/* EIR Field 5: Confirmation Value - Needed for LE Secure Connections */
uint8_t eirSecureConnConfirmation[18] = { 17, NDEF_BT_EIR_LE_SECURE_CONN_CONFIRMATION_VALUE };
memcpy(&eirSecureConnConfirmation[2], oob_data.le_sc_data.c, 16);
/* EIR Field 6: Randomizer Value - Needed for LE Secure Connections */
uint8_t eirSecureConnRandom[18] = { 17, NDEF_BT_EIR_LE_SECURE_CONN_RANDOM_VALUE };
memcpy(&eirSecureConnRandom[2], oob_data.le_sc_data.r, 16);
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirLeFlags);
if (rc != ERR_NONE)
{
Log("Erro encoding flags\n");
return rc;
}
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirLeAddress);
if (rc != ERR_NONE)
{
Log("Erro encoding address\n");
return rc;
}
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirLeRole);
if (rc != ERR_NONE)
{
Log("Erro encoding LE role\n");
return rc;
}
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirLocalName);
if (rc != ERR_NONE)
{
Log("Erro encoding local name\n");
return rc;
}
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirTk);
if (rc != ERR_NONE)
{
Log("Erro encoding TK\n");
return rc;
}
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirSecureConnConfirmation);
if (rc != ERR_NONE)
{
Log("Erro encoding Confirm\n");
return rc;
}
rc = ndefBluetoothSetEir(&bluetooth, (uint8_t *) &eirSecureConnRandom);
if (rc != ERR_NONE)
{
Log("Erro encoding Random\n");
return rc;
}
rc = ndefBluetoothLeInit(&ndefBt, &bluetooth);
if (rc != ERR_NONE)
{
Log("Erro Init LE\n");
return rc;
}
rc = ndefTypeToRecord(&ndefBt, &record);
if (rc != ERR_NONE)
return rc;
/* Encode the record starting after the first two bytes that are saved to store the NDEF file length */
ndefBuffer bufRecord = { &buffer[2], length - 2 };
rc = ndefRecordEncode(&record, &bufRecord);
if (rc != ERR_NONE)
{
Log("Erro Encode: %d\n", rc);
return rc;
}
/* Store the NDEF file length on the two first bytes */
buffer[0] = bufRecord.length >> 8;
buffer[1] = bufRecord.length & 0xFF;
Log("NDEF file length: %d\n", bufRecord.length);
return rc;
}I was abble to read some information with my smartphone, however I got "No DEF Data Storage Populated" and the pairing does not work as in classical.
Hi,
"however is seems that is not being correctly written in the tag": there is no tag... This is card emulation. The card emulation reads the data from the ndefFile[] buffer.
The content of ndefFile is wrongly encoded.
002B Length of the NDEF (43 bytes)
D2 Record Header
20 Record type Length (32)
0E Payload Length (14 bytes)
==> the message length is
- 1 byte for the record header +
- 1 byte for the record type length byte+
- 1 byte for the payload length byte +
- 32 bytes for the record type
- 14 bytes for the payload
Total is 49 types. As the 2 first bytes indicates a total length of 43 bytes, the message cannot be decoded by the mobile phone.
With the proper message length (i.e. 0x31), the BLE pairing record is correctly decoded:
Make sure to properly encode your BLE pairing record and to update ndefFile[0] and ndefFile[1] with the proper NDEF message length.
Rgds
BT
Hi,
the bufDeviceAddress should be populated only in BR/DR case. Therefore the following lines:
should be replaced by:
/* Mandatory field: bufDeviceAddress - Device Address (only for BR/EDR) */
ndefConstBuffer bufDeviceAddress = { (uint8_t *) oob_data.addr.a.val, 0 };
bluetooth.bufDeviceAddress = bufDeviceAddress;Having bufDeviceAddress different from 0 in case of BLE causes a side effect on the payload length computation. I have reported this to the development team in order to improve the robustness.
The payload should now have the correct length and it should be possible to properly decode the NDEF message.
Rgds
BT
Hello,
I think everything is OK with the record, the smartphone can decode it as a LE Secure Connection Bluetooth Record, however when I tap the phone the pairing does not start as it happens with normal BLE.
BR
