SSL, CAs and keeping your stuff safe

A capitalistic and system conformant talk about encryption.

Transcript

1. SSL, CAs and keeping your stuff safe
   BQSFTFOUBUJPOCZBSNJOSPOBDIFSGPSQZHSVOO
   http://lucumr.pocoo.org/ — @mitsuhiko
   

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2. SSL, CAs and keeping your stuff safe
   BQSFTFOUBUJPOCZBSNJOSPOBDIFSGPSQZHSVOO
   http://lucumr.pocoo.org/ — @mitsuhiko
   a capitalistic and system conformant talk about encryption
   

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3. Armin Ronacher
   Independent Contractor for Splash Damage / Fireteam
   Doing Online Infrastructure for Computer Games
   

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4. … The Problem with Programmers
   ~ Epilogue ~
   

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5. Programmers think everything
   is a technical problem
   

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6. Fraud
   ~ Chapter 1 ~
   

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7. XXXX-XXXX-XXXX-1234
   What is the worst that can happen?
   

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8. What makes Credit Card Numbers “secure”?
   

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9. theft
   ere will always be criminals
   

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10. prevented
    But what damage can they do?
    

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11. Bitcoin A Credit Card
    Strong Encryption Potentially No Encryption
    256 bit private key 16 digit number + checksum
    decentralized centralized
    √ x
    

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12. But I'd rather lose my credit card …
    

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13. Never

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14. LOL

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15. We Accept Stolen Creditcards
    

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16. e Protocol
    e Process
    is insecure
    is secure
    

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17. If the aud percentage is smaller than
    the transaction fees we're all good.
    

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18. It's too easy to forget the
    bigger picture
    

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19. of Lock Symbols and Encryption
    ~ Chapter 2 ~
    

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20. the lock symbol is a lie
    

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21. the lock stands for secure
    

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22. but so is encryption
    8
    7
    

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23. such security
    

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24. such buzzwords
    CRIME
    BEAST
    Heartbleed
    BREACH
    PFS
    

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25. users need to understand how to
    keep good om bad lock symbols /
    good om bad encryption.
    =
    -
    

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26. but even developers are not sure yet …
    

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27. remember why you encrypt
    (NSA

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28. Why do we Encrypt Traffic?
    ~ Chapter 3 ~
    

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30. public WiFi the unencrypted browser session
    kilLed
    

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31. ?
    Who is the Attacker?
    

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32. om secret agents to idiots
    

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33. om targeted to untargeted
    

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34. om low to high probability
    

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35. What You Need for Encryption
    ~ Chapter 4 ~
    

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36. passive vs active eavesdropping
    encryption authentication
    

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37. $ ssh pocoo.org
    The authenticity of host 'pocoo.org (148.251.50.164)' can't be established.
    RSA key fingerprint is 14:23:83:02:45:f9:9c:d0:eb:39:c7:14:42:f5:9f:9c.
    Are you sure you want to continue connecting (yes/no)?
    

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38. your user does not check ngerprints
    (your

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39. e
    Certificate Authorities
    thus:
    

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40. CAs are worthless for securing APIs
    let it be known that
    

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41. Protecting APIs and Services
    ~ Chapter 5 ~
    (non

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42. The Only Rule to Follow
    

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43. run your own CA
    issue certi cates for 24 hours
    trust your own CA only
    screw re ocations
    

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44. You trust your own CA by
    distributing the certi cate to
    everybody.
    

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45. If your root gets compromised,
    distribute new root certi cates.
    

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46. If an individual key gets compromised,
    in less than 24 hours everything is ne.
    

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47. from requests import get
    resp = get('https://api.yourserver.com/',
    verify='your/certificate.bundle')
    

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48. “But my awesome AntiVirus says
    your certi cate is not trusted.”
    — Windows User
    

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49. Certificate Authorities Again
    ~ Chapter 6 ~
    

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50. Hardly news: CAs are Broken
    

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51. But why are the broken?
    

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52. I Trust “TÜRKTRUST Elektronik Serti ka Hizmet
    Sağlayıcısı” to ouch for the identity of any domain on
    the planet.
    Trusting a CA:
    

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53. trusting half the world: one shitty employee in one shitty
    CA is enough to break your security.
    

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54. I Trust “Comodo” to ouch for the identity of “Foo
    Owner” foo.com.
    I only trust “Foo Owner” to ouch for the identity of
    api.foo.com
    What we actually want:
    

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55. if you have seen google.com being from Verisign and all
    the sudden google.com becomes a StartSSL certificate you
    know something might be wrong.
    

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56. Soon: Certificate Pinning?
    

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57. Frack OpenSSL and Question “Best Practices”
    ~ Chapter 7 ~
    

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58. Self-Signed Certificates are not bad. Just in browsers.
    

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59. Never. Ever. Look at OpenSSL's Source.
    

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60. OpenSSL's "patches" are even worse:
    Apple's OpenSSL always trusts system store :-/
    

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61. Requests by default trusts it's own bundle :-/
    (And does not even properly document how to use custom ones)
    

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62. With Heartbleed SSL was less secure than no SSL :-/
    

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63. Growing SSL
    ~ Chapter 8 ~
    

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64. Credit Cards were made for thousands of people
    Certificate Authorities were made for hundreds of sites
    

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65. OpenSSL was probably improperly audited
    

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66. See “OpenSSL Valhalla Rampage” :-(
    “i give up. reuse problem is unixable.
    dlg says puppet crashes”
    — tedu
    

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67. Plan for Failure
    ~ Chapter 9 ~
    

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68. what

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69. what happens to your user if he gets hacked?
    (food for thought: keyloggers are still a thing)
    

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70. what happens to your data
    

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71. what happens to your company
    

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72. encryption is hardened security
    it must not be your only defense
    

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73. ?
    Feel Free To Ask Questions
    Talk slides will be online on lucumr.pocoo.org/talks
    You can find me on Twitter: @mitsuhiko
    And gittip: gittip.com/mitsuhiko
    Or hire me: armin.ronacher@active-4.com
    

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