From bc51e3a9918ba94d57f1858a35e58ced65994d83 Mon Sep 17 00:00:00 2001
From: Sergio Costas <raster@rastersoft.com>
Date: Tue, 8 Dec 2020 17:09:03 +0100
Subject: [PATCH] Added python flasher

Added a python port of the flasher. It only works with already
'freed' devices, thus can be used to easily upload new firmware
when doing tests, without having to open the devices.
---
 flash.py | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 135 insertions(+)
 create mode 100755 flash.py

diff --git a/flash.py b/flash.py
new file mode 100755
index 00000000..44454d7e
--- /dev/null
+++ b/flash.py
@@ -0,0 +1,135 @@
+#!/usr/bin/env python3
+
+import bluepy
+import sys
+import time
+import struct
+
+class Flash(object):
+    def __init__(self):
+        super().__init__()
+        self._firmware = None
+        self._device = None
+        self._miEnabled = False
+        self._customEnabled = False
+
+    def loadFirmware(self, firmware_name):
+        with open(firmware_name, "rb") as firmware_file:
+            firmware = firmware_file.read()
+        signature = struct.unpack(">L",firmware[8:12])[0]
+        if signature != 0x4b4e4c54:
+            print("The file is not a valid firmware file. Aborting.")
+            sys.exit(-1)
+        print(f"The firmware is {len(firmware)} bytes in length.")
+        while 0 != (len(firmware) % 16):
+            firmware += bytes([0xff])
+        self._firmware = firmware
+        self._blockCount = int(len(firmware) / 16)
+        print(f"Count: {int(self._blockCount)}")
+
+    def disconnect(self):
+        if not self._doTest:
+            self._device.disconnect()
+
+    def connect(self, mac, doTest):
+        self._doTest = doTest
+        if doTest:
+            self._customAction()
+        else:
+            self._device = bluepy.btle.Peripheral(mac)
+            services = self._device.getServices()
+            self._services = {}
+            for service in services:
+                self._services[str(service.uuid)] = service
+            self._service = self._services['00010203-0405-0607-0809-0a0b0c0d1912']
+            self._writeCharacteristic = self._service.getCharacteristics(forUUID='00010203-0405-0607-0809-0a0b0c0d2b12')[0]
+            self._detectMi()
+
+    def _detectMi(self):
+        self._miEnabled = "ebe0ccb0-7a0a-4b0c-8a1a-6ff2997da3a6" in self._services
+        self._customEnabled = "00001f10-0000-1000-8000-00805f9b34fb" in self._services
+
+        if self._miEnabled:
+            print("Detected Mi Thermometer. Can't flash it.")
+            self.disconnect()
+            sys.exit(-1)
+        elif self._customEnabled:
+            print("Detected device with valid custom Firmware")
+            self._customAction()
+        else:
+            print("Detected device with not valid Firmware. Can't flash it.")
+            self.disconnect()
+            sys.exit(-1)
+
+    def _customAction(self):
+        self._otaCharSend(bytes([0x00, 0xff]))
+        self._otaCharSend(bytes([0x01, 0xff]))
+        if self._doTest:
+            endline = "\n"
+        else:
+            endline = "\r"
+        for c in range(self._blockCount):
+            print(f"Sending block {c} of {self._blockCount} ({int(100 * c / self._blockCount)}%)", end=endline)
+            offset = c * 16
+            blockCount = struct.pack("<H", c)
+            block = self._firmware[offset:offset + 16]
+            crc = self._crc16_modbus(blockCount + block)
+            self._otaCharSend(blockCount + block + crc)
+            if ((c + 1) % 8) == 0:
+                if self._doTest:
+                    print("Doing read")
+                else:
+                    self._writeCharacteristic.read()
+        blockCount = self._blockCount - 1
+        blockCountInverted = 65535 - blockCount
+        data = struct.pack("<HHH",0xff02, blockCount, blockCountInverted)
+        self._otaCharSend(data)
+        print()
+        print("Done")
+
+    def _crc16_modbus(self, data):
+        crc = 0x0ffff
+        for d in data:
+            crc ^= struct.unpack("B", bytes([d]))[0]
+            for l in range(8):
+                odd = crc & 0x0001
+                crc = (crc >> 1) & 0x7fff
+                if odd != 0:
+                    crc ^= 0xa001
+        return struct.pack("<H",crc)
+
+    def _otaCharSend(self, data):
+        if self._doTest:
+            for d in data:
+                d = hex(d)[2:]
+                if len(d) == 1:
+                    d = '0' + d
+                print(d, end = "")
+            print()
+        else:
+            try:
+                self._writeCharacteristic.write(data)
+            except:
+                print("Failed to send data to the device. Aborting.")
+                self.disconnect()
+                sys.exit(-1)
+
+
+
+    def waitForNotifications(self, timeout):
+        self._device.waitForNotifications(timeout)
+
+
+if len(sys.argv) < 3:
+    print("Usage: flash.py MAC_ADDRESS   FIRMWARE_FILE [test]")
+    sys.exit(-1)
+
+if len(sys.argv) == 4:
+    doTest = sys.argv[3] == 'test'
+else:
+    doTest = False
+
+manager = Flash()
+manager.loadFirmware(sys.argv[2])
+manager.connect(sys.argv[1], doTest)
+manager.disconnect()