Add optional bindkey support for CGG1. (#1407)

esphome/components/xiaomi_ble/xiaomi_ble.cpp

@@ -103,7 +103,7 @@ bool parse_xiaomi_message(const std::vector<uint8_t> &message, XiaomiParseResult
     return false;
   }
 
-  while (payload_length > 0) {
+  while (payload_length > 3) {
     if (payload[payload_offset + 1] != 0x10) {
       ESP_LOGVV(TAG, "parse_xiaomi_message(): fixed byte not found, stop parsing residual data.");
       break;
@@ -171,7 +171,10 @@ optional<XiaomiParseResult> parse_xiaomi_header(const esp32_ble_tracker::Service
     result.type = XiaomiParseResult::TYPE_MUE4094RT;
     result.name = "MUE4094RT";
     result.raw_offset -= 6;
-  } else if ((raw[2] == 0x47) && (raw[3] == 0x03)) {  // round body, e-ink display
+  } else if ((raw[2] == 0x47) && (raw[3] == 0x03)) {  // ClearGrass-branded, round body, e-ink display
+    result.type = XiaomiParseResult::TYPE_CGG1;
+    result.name = "CGG1";
+  } else if ((raw[2] == 0x48) && (raw[3] == 0x0B)) {  // Qingping-branded, round body, e-ink display — with bindkeys
     result.type = XiaomiParseResult::TYPE_CGG1;
     result.name = "CGG1";
   } else if ((raw[2] == 0xbc) && (raw[3] == 0x03)) {  // VegTrug Grow Care Garden

esphome/components/xiaomi_cgg1/sensor.py

@@ -3,6 +3,7 @@ import esphome.config_validation as cv
 from esphome.components import sensor, esp32_ble_tracker
 from esphome.const import (
     CONF_BATTERY_LEVEL,
+    CONF_BINDKEY,
     CONF_HUMIDITY,
     CONF_MAC_ADDRESS,
     CONF_TEMPERATURE,
@@ -27,6 +28,7 @@ CONFIG_SCHEMA = (
     cv.Schema(
         {
             cv.GenerateID(): cv.declare_id(XiaomiCGG1),
+            cv.Optional(CONF_BINDKEY): cv.bind_key,
             cv.Required(CONF_MAC_ADDRESS): cv.mac_address,
             cv.Optional(CONF_TEMPERATURE): sensor.sensor_schema(
                 UNIT_CELSIUS, ICON_EMPTY, 1, DEVICE_CLASS_TEMPERATURE
@@ -50,6 +52,8 @@ def to_code(config):
     yield esp32_ble_tracker.register_ble_device(var, config)
 
     cg.add(var.set_address(config[CONF_MAC_ADDRESS].as_hex))
+    if CONF_BINDKEY in config:
+        cg.add(var.set_bindkey(config[CONF_BINDKEY]))
 
     if CONF_TEMPERATURE in config:
         sens = yield sensor.new_sensor(config[CONF_TEMPERATURE])

esphome/components/xiaomi_cgg1/xiaomi_cgg1.cpp

@@ -10,6 +10,7 @@ static const char *TAG = "xiaomi_cgg1";
 
 void XiaomiCGG1::dump_config() {
   ESP_LOGCONFIG(TAG, "Xiaomi CGG1");
+  ESP_LOGCONFIG(TAG, "  Bindkey: %s", hexencode(this->bindkey_, 16).c_str());
   LOG_SENSOR("  ", "Temperature", this->temperature_);
   LOG_SENSOR("  ", "Humidity", this->humidity_);
   LOG_SENSOR("  ", "Battery Level", this->battery_level_);
@@ -31,8 +32,9 @@ bool XiaomiCGG1::parse_device(const esp32_ble_tracker::ESPBTDevice &device) {
     if (res->is_duplicate) {
       continue;
     }
-    if (res->has_encryption) {
-      ESP_LOGVV(TAG, "parse_device(): payload decryption is currently not supported on this device.");
+    if (res->has_encryption &&
+        (!(xiaomi_ble::decrypt_xiaomi_payload(const_cast<std::vector<uint8_t> &>(service_data.data), this->bindkey_,
+                                              this->address_)))) {
       continue;
     }
     if (!(xiaomi_ble::parse_xiaomi_message(service_data.data, *res))) {
@@ -57,6 +59,18 @@ bool XiaomiCGG1::parse_device(const esp32_ble_tracker::ESPBTDevice &device) {
   return true;
 }
 
+void XiaomiCGG1::set_bindkey(const std::string &bindkey) {
+  memset(bindkey_, 0, 16);
+  if (bindkey.size() != 32) {
+    return;
+  }
+  char temp[3] = {0};
+  for (int i = 0; i < 16; i++) {
+    strncpy(temp, &(bindkey.c_str()[i * 2]), 2);
+    bindkey_[i] = std::strtoul(temp, NULL, 16);
+  }
+}
+
 }  // namespace xiaomi_cgg1
 }  // namespace esphome
 

esphome/components/xiaomi_cgg1/xiaomi_cgg1.h

@@ -13,6 +13,7 @@ namespace xiaomi_cgg1 {
 class XiaomiCGG1 : public Component, public esp32_ble_tracker::ESPBTDeviceListener {
  public:
   void set_address(uint64_t address) { address_ = address; }
+  void set_bindkey(const std::string &bindkey);
 
   bool parse_device(const esp32_ble_tracker::ESPBTDevice &device) override;
 
@@ -24,6 +25,7 @@ class XiaomiCGG1 : public Component, public esp32_ble_tracker::ESPBTDeviceListen
 
  protected:
   uint64_t address_;
+  uint8_t bindkey_[16];
   sensor::Sensor *temperature_{nullptr};
   sensor::Sensor *humidity_{nullptr};
   sensor::Sensor *battery_level_{nullptr};