This allows you to parse advertisements from BTHome compatible devices, e.g. a Shelly BLU H&T sensor. It is an (incomplete) implementation of the BTHome v2 format. It relies on other low-level bits to do the bluetooth / BLE communication, e.g. go-ble.
- incomplete: I only implemented what I needed for my sensors
- PoC: This is just a quick & dirty PoC, use at your on risk
Encrypted packets can be read, the decryption as documented has been implemented.
For Shelly devices you can use the Shelly BLE Debug Android app to
encrypt your sensor. The sensor will then be provisioned with a random
encryption key. After encryption you can "Read" the device and can find the key
in settings.encryptionKey, this should be a 32 character string (16 byte hex
encoded). This key can then be used with this parser by adding it and the
sensor's MAC via the AddEncryptionKey method.
Encryption for one sensor is implemented in the cmd/bluezScan.
In the example in cmd/readSensors you find an implementation of a tool which listens for advertisements of sensors and just prints the parsed BTHome data:
: sudo go run cmd/readSensors/main.go -mac 7c:c6:b6:71:9d:b5 -mac 7c:c6:b6:71:98:d7
2024/11/01 15:40:14 Scan on default starting
2024/11/01 15:40:28 [7c:c6:b6:71:9d:b5] BTHomePacket{Encrypted: false, Trigger: Button, BTHomeVersion: 2, ID: 222, Battery: [100], Humidity: [59], Temperature: [20.80], Button: [Press]}
2024/11/01 15:40:37 [7c:c6:b6:71:98:d7] BTHomePacket{Encrypted: false, Trigger: Button, BTHomeVersion: 2, ID: 208, Battery: [100], Humidity: [53], Temperature: [22.00]}
^C
2024/11/01 15:40:39 Scan on device default stopped
:
There is another example in cmd/bluezScan, which uses tiny-go/bluetooth which in turn uses BlueZ under the hood (on Linux), and implements a similar tool as the example above:
: go run cmd/bluezScan/main.go
2024/11/02 11:31:20 scanning...
2024/11/02 11:31:37 [7C:C6:B6:71:98:D7] BTHomePacket{Encrypted: false, Trigger: Button, BTHomeVersion: 2, ID: 119, Battery: [100], Humidity: [55], Temperature: [19.90]}
2024/11/02 11:32:09 [7C:C6:B6:71:9D:B5] BTHomePacket{Encrypted: false, Trigger: Button, BTHomeVersion: 2, ID: 144, Battery: [100], Humidity: [56], Temperature: [20.10]}
2024/11/02 11:32:11 [7C:C6:B6:76:58:CE] BTHomePacket{Encrypted: true, Trigger: Button, BTHomeVersion: 2, ID: 95, Battery: [100], Humidity: [54], Temperature: [21.20]}
^Csignal: interrupt
: