The document discusses using Rspamd for spam filtering in FreeBSD mail architecture. It describes the existing complicated mail flows with many relays and aliases. Rspamd helps filter spam from mailing lists in real-time. Issues with DKIM signatures breaking when mail is modified are discussed. Future plans include splitting mail flows and using both generic and personalized Bayesian filtering statistics. The document provides an overview of how Rspamd works and some existing problems it helps address for FreeBSD mail architecture.

1. Rspamd in
FreeBSD Mail

2. FreeBSD Mail

3. Mail architecture
Freefall Mailman
MX1 MX2

4. Mail architecture
Freefall Mailman
MX1 MX2

5. Mail architecture
Freefall Mailman
MX1 MX2

6. Mail architecture
Freefall Mailman
MX1 MX2

7. Mail architecture
Freefall Mailman
MX1 MX2

8. Mail architecture
Freefall Mailman
MX1 MX2

9. Mail architecture
Freefall Mailman
MX1 MX2

10. Mail architecture
Freefall Mailman
MX1 MX2

11. Mail architecture
Freefall Mailman
MX1 MX2

12. Mail architecture

13. Mail architecture

14. Mail architecture
• Complicated mail flows:

15. Mail architecture
• Complicated mail flows:
• many relays

16. Mail architecture
• Complicated mail flows:
• many relays
• many aliases

17. Mail architecture
• Complicated mail flows:
• many relays
• many aliases
• non-trivial circuits

18. Mail architecture
• Complicated mail flows:
• many relays
• many aliases
• non-trivial circuits
• Lots of legacy decisions

19. Add some Rspamd

20. Rspamd in action
Real-time scan stats (SandyBridge 4 cores Xeon)

21. Core
Proxy
Scan Layer
• Balancing
• Retransmits
• Health check
• SPF
• DKIM
• DMARC
• ARC
• SURBL Bayes NN Regexp Rules
Data storage
Proxy Layer
• Encryption
• Compression
• Mirroring
MTA
Milter/HTTP

22. Existing problems

23. Existing problems

24. Existing problems
• Spam in the mailing lists

25. Existing problems
• Spam in the mailing lists
• DKIM signatures breaking

26. Existing problems
• Spam in the mailing lists
• DKIM signatures breaking
• Controlling mail flows

27. Existing problems
• Spam in the mailing lists
• DKIM signatures breaking
• Controlling mail flows

28. Spam in mailing lists
Before Rspamd

29. Spam in mailing lists
Before Rspamd

30. Spam in mailing lists

31. Spam in mailing lists

32. Spam in mailing lists

33. Spam in mailing lists

34. DKIM in mailing lists
What usually happens
d=gmail.com
Message modified

35. DKIM in mailing lists
What usually happens
d=gmail.com
Message modified

36. DKIM in mailing lists
What usually happens
d=gmail.com
Message modified

37. DKIM in mailing lists
What should happen
d=gmail.com d=freebsd.org
Message modified

38. DKIM in mailing lists
What should happen
d=gmail.com d=freebsd.org
Message modified

39. DKIM in mailing lists
What should happen
d=gmail.com d=freebsd.org
Message modified

40. DKIM in mailing lists
Or, even better, ARC…
i=1,cv=none
i=2,cv=pass Message modified
AR: Arc passed

41. ARC in mailing lists
Interoperation

42. ARC in mailing lists
Interoperation

43. ARC in mailing lists
Interoperation

44. Signing issues

45. Signing issues

46. Signing issues
• Complicated architecture

47. Signing issues
• Complicated architecture
• Mail is seen many times

48. Signing issues
• Complicated architecture
• Mail is seen many times
• Need to enable/disable checks many times

49. Signing issues
• Complicated architecture
• Mail is seen many times
• Need to enable/disable checks many times
• We should not sign spam

50. Signing issues
Splitting flows

51. Future plans

52. Messages Modifications
What do we have

53. Messages Modifications
Proposed solution

54. Core
Proxy
Scan Layer
• Balancing
• Retransmits
• Health check
• SPF
• DKIM
• DMARC
• ARC
• SURBL Bayes NN Regexp Rules
Data storage
Proxy Layer
• Encryption
• Compression
• Mirroring
MTA
Milter

55. Personal Bayes

56. Personal Bayes
• We have many developers who are eager to
improve spam filter

57. Personal Bayes
• We have many developers who are eager to
improve spam filter
• They all have different preferences

58. Personal Bayes
• We have many developers who are eager to
improve spam filter
• They all have different preferences
• Idea: use both generic and personalised
statistics

60. Clickhouse queries

61. Questions?
Vsevolod Stakhov
https://rspamd.com
vsevolod@rspamd.com