A simple MODBUS server

1. Have a Simple MODBUS Server
StarNight @ HITCON 2019 Lighting Talk

2. Who am I
潘建宏 / Jian-Hong Pan (StarNight)
You can find me at ～
http://www.slideshare.net/chienhungpan/
GitHub : starnight

3. https://github.com/starnight/Modbus-Server

4. Specifications
● MODBUS Application Protocol Specification
V1.1b3
● MODBUS Messaging on TCP/IP
Implementation Guide V1.0b

5. Client Server
PLC,
Sensors ...
PLC,
HMI,
PC ...

6. MODBUS over Serial (RS-232/485/422)
Ref: MODBUS Application Protocol Specification V1.1b3

7. Ref: MODBUS Application Protocol Specification V1.1b3

8. MODBUS over TCP/IP
Ref: MODBUS Messaging on TCP/IP Implementation Guide V1.0b

9. MBAP Header Layout
Ref: MODBUS Messaging on TCP/IP Implementation Guide V1.0b

10. Ref: MODBUS Application Protocol Specification V1.1b3

11. Function Code 01 (0x01) Read Coils for example
*N= Quantity of Outputs / 8, if the remainder is different of 0 => N = N+1
Ref: MODBUS Application Protocol Specification V1.1b3

12. Ref: MODBUS Application
Protocol Specification V1.1b3

13. Demo

14. MODBUS/TCP Security Protocol Specification