对于具有 ProximityUUID E2C56DB5-DFFB-48D2-B060-D0F5A71096E0
、major 0
、minor0
和 calibrated Tx Power of -59
RSSI 的 iBeacon,传输的 BLE 广告数据包如下所示:
d6 be 89 8e 40 24 05 a2 17 6e 3d 71 02 01 1a 1a ff 4c 00 02 15 e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 00 00 00 00 c5 52 ab 8d 38 a5
这个数据包可以分解如下:
d6 be 89 8e # Access address for advertising data (this is always the same fixed value)
40 # Advertising Channel PDU Header byte 0. Contains: (type = 0), (tx add = 1), (rx add = 0)
24 # Advertising Channel PDU Header byte 1. Contains: (length = total bytes of the advertising payload + 6 bytes for the BLE mac address.)
05 a2 17 6e 3d 71 # Bluetooth Mac address (note this is a spoofed address)
02 01 1a 1a ff 4c 00 02 15 e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 00 00 00 00 c5 # Bluetooth advertisement
52 ab 8d 38 a5 # checksum
该数据包的关键部分是蓝牙广告,可以这样分解:
02 # Number of bytes that follow in first AD structure
01 # Flags AD type
1A # Flags value 0x1A = 000011010
bit 0 (OFF) LE Limited Discoverable Mode
bit 1 (ON) LE General Discoverable Mode
bit 2 (OFF) BR/EDR Not Supported
bit 3 (ON) Simultaneous LE and BR/EDR to Same Device Capable (controller)
bit 4 (ON) Simultaneous LE and BR/EDR to Same Device Capable (Host)
1A # Number of bytes that follow in second (and last) AD structure
FF # Manufacturer specific data AD type
4C 00 # Company identifier code (0x004C == Apple)
02 # Byte 0 of iBeacon advertisement indicator
15 # Byte 1 of iBeacon advertisement indicator
e2 c5 6d b5 df fb 48 d2 b0 60 d0 f5 a7 10 96 e0 # iBeacon proximity uuid
00 00 # major
00 00 # minor
c5 # The 2's complement of the calibrated Tx Power
任何可以配置为发送特定广告的蓝牙 LE 设备都可以生成上述数据包。我已经使用 Bluez 配置了一台 Linux 计算机来发送此广告,并且运行 Apple 的 AirLocate 测试代码的 iOS7 设备将其作为具有上述指定字段的 iBeacon 拾取。请参阅:将 BlueZ Stack 用作外设(广告商)
此博客包含有关逆向工程过程的完整详细信息。