1. What is MGO? ●Metal Gear o A bipedal nuclear-equipped tank ●Online o Controlled by or connected to a network. ●Metal Gear Online o A bipedal nuclear tank controlled by the internet

2. Cyber Necromancy: Reverse Engineering Dead Protocols

3. ●Matthew Halchyshak o Security Technician for Security Innovation

4. Warning ●Not development ●Not exploitation ●Just a cool project to revive a video game

5. Problems ●Servers are down o Minimal Packet Capture o No LAN Play ●PS2 (mips32) o No debugging interface o PCSX2 Memory Dumps ●PS3 (Cell BE) o Removed with official update o Requires a custom firmware

6. High-level Overview 1.Redirect traffic to our controlled server 2.Implement handlers for known protocols o HTTP o STUN o etc. 3.Implement unknown game protocol

7. Traffic Redirection ●Patching o Distribution? ●Buy the domains o Still owned ●Custom DNS

8. Dynamic Network Authentication ●Prevent cheating and piracy online o Bypass for piracy is old o Bypass for games no longer online is not ●Google is your friend o Sony SDK o DNAS Documentation

9. Dynamic Network Authentication ●Failure o Never managed to recreate DNAS ●“NewDNASConnect” o Found this string, lead to a function o What happens when you return 0 from it?

10. Dynamic Network Authentication ●Binary Patching o Reproduction and distribution? o Packed binaries ●Cheat Devices o Inject a small bit of code into a game  Code allows overwriting 4 bytes of memory at a time o Less than ideal but it works  Other games have not needed this

11. “Cheats” ●C1322414 00007474 ●2036b1e8 24020000 ●2036b1ec 03e00008 ●2036b1f0 00000000

12. “Cheats” ●Format o First Character represented the type of cheat  Caaaaaaa bbbbbbbb ●if 0x8aaaaaaa == 0xbbbbbbbb  2aaaaaaa bbbbbbbb ●Overwrite 0x8aaaaaaa o Many types of codes

13. Reversing the Protocol

14. ●Packets! Packets! Packets! ●Cannot get packets if the server is dead ●Examine and compare everything

15. Client Packets

20. Reversing the Protocol ●No NULL bytes ●..Zp comes up often

21. And it’s XOR…

24. Reversing the Protocol ●c022b8e51bd997c3baf6a587ba395d8f ●f252244cd1f91de6baffa2ad93f4a1f8 ●7eb97a668342081d5685c0c100dfa3c7 ●f252244cd1f91de6baffa2ad93f4a1f8 ●Look familiar? o MD5 (Header + Payload)

25. Reversing the Protocol ●Header (8 bytes) o Command Identifier (2 bytes) o Payload Length (2 bytes) o Sequence (4 bytes) ●Hash (16 bytes) ●Payload?

26. Response Payloads

27. The Ideal Way ●Packet Captures o Replay and experiment o Matter of determining transformation

30. Experimentation ●Changed visible names ●Changed IPs and setup listeners ●Changed Unknown value to [A-E] o Hopefully its visible in some way

32. That was easy

33. The Harder Way ●No packet capture

34. Determining the Payloads ●Are there are commonalities that run through the payloads. o Is there are structure to the payloads?  XML? JSON? SOAP? Custom? o Cryptography  https://kerckhoffs.googlecode.com/files/Groebert- Automatic.Identification.of.Cryptographic.Primitiv es.in.Software.pdf https://kerckhoffs.googlecode.com/files/Groebert- Automatic.Identification.of.Cryptographic.Primitiv es.in.Software.pdf

35. Determining the Payloads ●Experimentation o First 4 bytes are a result code  0x00000000 = Success (normally)  Anything else is displayed back to user o Error only display IFF Command id is correct o Server’s response is usually +1 of request

36. Determining the Payloads ●Guess Work o Blank  User Settings o NULL (0x00)  Create Game - first half o ‘0’ (0x30)  HTTP API o Success (0x00000000)  ‘Worked’ but doesn’t do what it should o Something else?

37. Exploring Items 00 00 00 00 21 00 00 00 01

38. Exploring Items 00 00 00 01 21 00 00 00 01

39. Exploring Items 00 00 00 01 21 00 00 00 03

40. Exploring Items 00 00 00 01 21 00 00 00 07

41. Exploring Items 00 00 00 00 21 00 00 00 01

42. Exploring Items 00 00 00 01 21 00 00 00 07

43. Exploring Items

44. ●Slow and tedious but not too difficult

45. Complex Payloads ●Packets? Nope. ●Easily Guessable? Nope.

46. Friends List ●Exhausted simple cases ●Random payloads revealed nothing

48. Join Game ●Packets? No. Easily Guessable? Nope. ●Anything similar? Nope.

50. Join Game ●Step 1 o 0x4113 - Game Data o Same request is made for ‘Host Information’  Used Host Information to determine response

52. Join Game ●Step 2 o 0x4102 - Player Stats  Requests information about the host’s ingame stats

53. Join Game ●Static Analysis o ELF is packed o No official debugging functionality  Emulator memory dump

54. Join Game ●Finding the code path o Nearby strings  None o Magic Numbers  0x4103  XOR Code

55. Join Game

56. ●Function has several calls of the form o jal -- function call o bne v0 0 -- branch if return not 0  Repeat about 15 times

57. Join Game ●Two Options o Follow code path and determine where it fails  NOP the check (Patch)  Determine what data would make it pass ●Complicated payloads o Expects data for 0x4104 and 0x4105 ●Ultimately patched

58. Join Game ●Past Requests o Game Information o Player Information o Host Stats -- patched o now 0x4320?

59. Join Game ●External Resources o Google is your friend o Other online games  Pro Evolution Soccer  Metal Gear Online 2 ● Had this particular packet

60. Join Game ●Client sends data over UDP to Host ●Unexpectedly host sends 0x4340

61. 0x4340 ●No error message o Host stops responding to client UDP ●Request Payload o Joining Player Id

62. 0x4340

64. ●Found 4341 handler in memory dump ●Function makes a lot of calls but doesn’t check return values o Only reads 4 bytes from payload

65. 0x4340

66. 0x4341 ●Structure o Success Code - 4 bytes o Player Id - 4 bytes

67. Success!

68. What’s next?

70. Conclusion

71. Warnings ●A lot of work o Protocol and Server emulation took about 10 months o More than 80 commands. o Headaches and frustration o Not a lot of existing reference material ●People are crazy o Trolls and complaints about not being done yet ●Copyrights and DMCA o DMCA exception for interoperability o Terms of Service

72. Credits ●GhzGangster (Derrik Touve) ●Zak o http://obsvr.com http://obsvr.com ●Mohamed Saher o http://twitter.com/halsten http://twitter.com/halsten o http://halsten.info http://halsten.info ●Wtfareuthinking1 ●Jayveer

73. Useful tools ●Used public IDA scripts to parse PS3 ELF ○https://github.com/kakaroto/ps3idahttps://github.com/kakaroto/ps3ida ○Revealed SDK functions and references ○More analysis in general than PS2

74. Questions? ●Matthew Halchyshak o matthew@0x0539.net matthew@0x0539.net o @iamcuri0us ●Joseph Tartaro o joseph.tartaro@gmail.com joseph.tartaro@gmail.com o @droogie1xp