The document discusses reverse engineering in the context of BLE (Bluetooth Low Energy) technology, focusing on the creation and management of a central manager for handling Bluetooth connections in iOS apps. It highlights the structure of code involving classes, attributes, methods, and object interactions to retrieve and manage data from heart rate sensors using Bluetooth services. It also provides useful links and references for further information on Swift and Bluetooth technologies.

1. Laura Barilli laura.barilli@mail.polimi.it
Luisa Cucugliato luisa.cucugliato@mail.polimi.it
Thursday, April 12, 2016
Politecnico di Milano
Dipartimento di Elettronica, Informazione e Bioingegneria (DEIB)
NECST lab, Via Ponzio, Building 20
Reverse engineering

2. Reverse Engineering
Open source codeProcessed data
1

3. Classes
Attributes
Methods
Objects
P1 P2
Swift
[*] https://www.xcoding.it 2
[*]

4. Classes
Attributes
Methods
Objects
Swift
View Controller Model
Code
According to the
output of view it
chages execution
Preservation
of information
User interface
[*] https://developer.apple.com/swift/ 3
[*]

5. Bluetooth Low Energy
[*] https://learn.adafruit.com/introduction-to-bluetooth-low-energy/introduction 4
[*]
Bluetooth Smart
Power version of Bluetooth
that was built for the devices
that run for long periods
Platform supported
•iOS5+
•Android 4.3+
•Apple OS X 10.6+
•Windows 8
•GNU/Linux Vanilla BlueZ 4.93+

6. CB Core Bluetooth
There are two major players involved in all Bluetooth low energy communication:
central and peripheral
https://developer.apple.com/ 4
Smartphone Device
• CB Central Manager: object that
controls and manages the Bluetooth
of the iPhone
• Core Bluetooth: Library that manages
bluetooth connection

7. Peripheral
CB Central Manager
Service 1
Characteristic
Characteristic
Characteristic
Service 2
Characteristic
Characteristic
Characteristic
Service 3
Characteristic
Characteristic
Characteristic
Central Device Central Device
Service 4
Characteristic
Characteristic
Characteristic
https://developer.apple.com/ 5

8. Peripheral
CB Central Manager
Heart Rate
Characteristic
Characteristic
Characteristic
Vibration
Characteristic
Characteristic
Characteristic
Steps
Characteristic
Characteristic
Characteristic
Central Device Central Device
Upgrade
Characteristic
Characteristic
Characteristic
https://developer.apple.com/ 5

9. Peripheral
CB Central Manager
HEART RATE
Characteristic
Characteristic
Characteristic
Vibration
Characteristic
Characteristic
Characteristic
Steps
Characteristic
Characteristic
Characteristic
Central Device Central Device
Upgrade
Characteristic
Characteristic
Characteristic
https://developer.apple.com/ 5

10. Overview of code
APP
Initialization and allocation of
Central Manager
Research peripherals
Find peripherals?
Research Services
Find services?
Research characteristics
HEART RATE
YES
NO
YES
NO
6

11.  Allocate and initialize a Central Manager instance
Verify the state of Central Manager
Central Manager
7

12. Peripherals
 Interface view
Mi
 Controller
Every peripheral is saved in an array
which is shown on the Table View
8

13. Services
 UUID: Universally Unique Identifier
Numbers which identificate a specific
service
Standard services have a 16-bit UUID
9

14. Heart Rate Service
 Assigned Number: 0x180D
 Two characteristics: 2A37 and 2A39
10
The Heart Rate Service shows heart rate and other data related to a
heart rate sensor
PPG sensor Bpm

15. Results
MiHeart
11

16. Contacts
Reverse Engineering of
Biomedical Elaborated Signal
Laura.barilli@mail.polimi.it
Luisa.cucugliato@mail.polimi.it
https://www.facebook.com/reebes.project2016/
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