1. The FPX KCPSM Module Exercise 1 Henry Fu The Layered Protocol Wrappers Exercise: Network Data Encryption / Decryption Using ROT13 Algorithm Henry Fu Washington University Applied Research Lab Supported by: NSF ANI-0096052 and Xilinx Corp. http://www.arl.wustl.edu/arl/projects/fpx/fpx_kcpsm/ hwf1@arl.wustl.edu

2. The FPX KCPSM Module Exercise 2 Henry Fu The Layered Protocol Wrappers Exercise Network data encryption / decryption using ROT13 algorithm –Rotates characters by 13 places ‘A’  ‘N’, ‘M’  ‘Z’, ‘a’  ‘n’, ‘m’  ‘z’ –Encryption Example: ‘Hello World’ encrypts to ‘Uryyb Jbeyq’ –Decryption Example: ‘Uryyb Jbeyq’ decrypts to ‘Hello World’

3. The FPX KCPSM Module Exercise 3 Henry Fu Approach to the ROT13 Algorithm Consider the following four cases –IF (ch >= ‘A’) && (ch <= ‘M’) Rotate “Right” ch by 13 characters –IF (ch >= ‘N’) && (ch <= ‘Z’) Rotate “Left” ch by 13 characters –IF (ch >= ‘a’) && (ch <= ‘m’) Rotate “Right” ch by 13 characters –IF (ch >= ‘n’) && (ch <= ‘z’) Rotate “Left” ch by 13 characters

4. The FPX KCPSM Module Exercise 4 Henry Fu The ROT13 Module Package –Detailed information on the Internet: http://www.arl.wustl.edu/arl/projects/fpx/fpx_kcpsm/ –Download the ROT13 Module Package Right click on ROT13.tar.gz Save it to h:\ –Extract the ROT13 Module Package Open a cygwin window –cd /cygdrive/h/ –gunzip ROT13.tar.gz –tar xvf ROT13.tar

5. The FPX KCPSM Module Exercise 5 Henry Fu The ROT13 Module Package (More) The ROT13 Module Package includes –ROT13/sim/ Modelsim simulation directory –ROT13/syn/ Synplicity, Xinlinx backend synthesis directory –ROT13/vhdl/ VHDL source directory –ROT13/wrappers/ Layered Protocol Wrappers package directory

6. The FPX KCPSM Module Exercise 6 Henry Fu The ROT13 Module Framework The ROT13 Module (“module.vhd”) is based on the ExampleApp Module –Instantiate the UDP Wrapper –Instantiate the ROT13 Application (“rot13app.vhd”) Instantiate the UDPEcho entity Instantiate four parallel ROT13 entity (“rot13.vhd”) –D_MOD_IN is 32-bit data bus, but we need to encrypt on a character boundary (8-bit data)

7. The FPX KCPSM Module Exercise 7 Henry Fu Overview of the ROT13 Application 32 – Bit Data D_MOD_IN 32 – Bit Data D_OUT_MOD UDPEcho Entity ROT13 Entity ROT13 Entity ROT13 Entity ROT13 Entity

8. The FPX KCPSM Module Exercise 8 Henry Fu The ROT13 Entity The ROT13 encrypts / decrypts the characters stored in the UDP payload –Implement a state machine that steps through the ATM Cells Looks for the start of the ATM Cell (SOF) Looks for the start of the UDP Datagram (SOD) Looks for the start of the UDP Payload Encrypts the UDP Payload with the ROT13 algorithm when there are valid data Looks for the end of the ATM Cell (EOF)

9. The FPX KCPSM Module Exercise 9 Henry Fu State Diagram of the ROT13 State Machine IDLEREQ REQ2UDPPayload SOF = ‘1’ SOD = ‘1’EOF = ‘1’ DataEn = ‘1’ IF DataEn = ‘1’ then Encrypts / Decrypts Payload

10. The FPX KCPSM Module Exercise 10 Henry Fu VHDL Process of the ROT13 State Machine type StateType is (Idle, Req1, Req2, UDPPayload); -- states signal state, nx_state : StateType; -- current and new state state_machine: process (Reset_l, state, sof_in, dataen_in, eof_in, sod_in, data_in) variable tmp_state : StateType; -- new state variable tmp_data : UNSIGNED (7 downto 0); begin -- process state_machine -- default value tmp_state := state; tmp_data := UNSIGNED (data_in); -- details of state machine goes here -- set state nx_state <= tmp_state; data_out <= std_logic_vector (tmp_data); dataen_out <= dataen_in; sof_out <= sof_in; eof_out <= eof_in; sod_out <= sod_in; end process state_machine;

11. The FPX KCPSM Module Exercise 11 Henry Fu Simulating the ROT13 Module Modelsim is used to simulate the ROT13 –Go to the sim directory and create the input file cd ROT13/sim/ cp HELLO.DAT INPUT_CELLS.DAT –Compile the module and start Modelsim Make compile Make sim –In Modelsim main window, type: do testbench.do run 3000

12. The FPX KCPSM Module Exercise 12 Henry Fu Simulating the ROT13 Module (More) The input data coming into the module SOF indicates the start of an ATM Cell SOD indicates the start of an UDP Datagram DataEn indicates the data is valid EOF indicates the end of an ATM Cell The last two valid words are the ATM Trailer

13. The FPX KCPSM Module Exercise 13 Henry Fu Simulating the ROT13 Module (More) The output data going out of the module The UDPPayload has been encrypted / decrypted

14. The FPX KCPSM Module Exercise 14 Henry Fu Error Handling by the Protocol Wrappers What happens if the incoming data is not an UDP Datagram? –If the incoming data is an ATM cell Frame Processor drops the cell –If the incoming data is an AAL5 frame IP Processor drops the cell –If the incoming data is an IP packet UDP Processor does not assert the SOD signal  Application only needs to handle the last case

15. The FPX KCPSM Module Exercise 15 Henry Fu State Diagram of the New State Machine IDLEREQ REQ2UDPPayload SOF = ‘1’ SOD = ‘1’EOF = ‘1’ DataEn = ‘1’ IF DataEn = ‘1’ then Encrypts / Decrypts Payload EOF = ‘1’

16. The FPX KCPSM Module Exercise 16 Henry Fu Simulating the new ROT13 Modify the ROT13 entity to handle this case Simulate the updated ROT13 entity –Go to the sim directory and create the IPv4 file cd ROT13/sim/ cp IPv4.DAT INPUT_CELLS.DAT –Compile the module in Cygwin Bash Shell Make compile –In Modelsim main window, type: restart -f run 3000

17. The FPX KCPSM Module Exercise 17 Henry Fu Simulating the new ROT13 (More) The IPv4 input data coming into the module SOD is not asserted between SOF and EOF

18. The FPX KCPSM Module Exercise 18 Henry Fu Simulating the new ROT13 (More) The IPv4 output data going out of the module The IP Payload is not modified by the ROT13 entity

19. The FPX KCPSM Module Exercise 19 Henry Fu Synthesizing the ROT13 Module Synplicity is used to synthesize the ROT13 –Go to the synthesis directory cd ROT13/syn/ –Start Synplicity make syn

20. The FPX KCPSM Module Exercise 20 Henry Fu Synthesizing the ROT13 Module (More) Files that are included in the project

21. The FPX KCPSM Module Exercise 21 Henry Fu Synthesizing the ROT13 Module (More) Click to change implementation option

22. The FPX KCPSM Module Exercise 22 Henry Fu Implementation Options for the ROT13

23. The FPX KCPSM Module Exercise 23 Henry Fu Implementation Options for the ROT13

24. The FPX KCPSM Module Exercise 24 Henry Fu Implementation Options for the ROT13

25. The FPX KCPSM Module Exercise 25 Henry Fu Implementation Options for the ROT13

26. The FPX KCPSM Module Exercise 26 Henry Fu Running the Implementation Click to run implementation

27. The FPX KCPSM Module Exercise 27 Henry Fu Synthesizing with Xilinx Backend Tools Xilinx backend tools are used to perform backend synthesis on the ROT13 module –Go to the implementation directory cd ROT13/syn/rad-xcve1000/ Start Xilinx backend script./build

28. The FPX KCPSM Module Exercise 28 Henry Fu Contents of the Xilinx Backend Script Xilinx Backend Script –NGDBUILD Translates and merges the various source files of a design into a single "NGD" design database. –NGD2VHDL Translates an NGD file (NGDBUILD output) into an VHDL simulation netlist which is intended for post- synthesis simulation

29. The FPX KCPSM Module Exercise 29 Henry Fu Contents of the Xilinx Backend Script –MAP Maps the logic gates of the NGD file (NGD output) into the CLBs and IOBs of the physical device, and writes out this physical design to an NCD file –PAR Places and routes a design's logic components contained within an NCD file (MAP output) based on the layout and timing requirements specified within the Physical Constraints File (PCF)

30. The FPX KCPSM Module Exercise 30 Henry Fu Contents of the Xilinx Backend Script –BITGEN Creates the configuration (BIT) file based on the contents of a physical implementation file (NCD) and defines the behavior of the programmed FPGA ngdbuild -p xcv1000e-7-fg680 rad_loopback -uc rad_loopback.ucf ngd2vhdl -w rad_loopback.ngd rad_loopback_sim.vhd map -p xcv1000e-7-fg680 -o top.ncd rad_loopback.ngd rad_loopback.pcf par -w -ol 2 top.ncd rad_loopback.ncd rad_loopback.pcf bitgen rad_loopback.ncd -b -l -w -f bitgen.ut

31. The FPX KCPSM Module Exercise 31 Henry Fu Conclusion In this ROT13 Module Exercise –Implement a network module using the Layered Protocol Wrappers –Simulate the module using Module –Examine the generated input / output control signals and various levels of data processing –Handle special error case –Synthesize the ROT13 Module