Don’t waste time on learning cryptography: better use it properly

#crypto #security #trust

Presented at Owasp Winter 2017, Kyiv, Ukraine and at DevExperience18 in Iasi, Romania.

1. The typical engineering workflow "we should protect the data, what shall we do", and possible mistakes.
2. What is "boring crypto", what do we want from using crypto-products.
3. Possible solutions: HSM / TPM / software crypto.
4. How to select appropriate software crypto: libs, systems, containers.
5. We want crypto to be similar to the Edison lamp: controllable and boring system.

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If you can't tap on the link inside slides, please open as pdf (button on the right).

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Crypto in our lives: why you shouldn’t spend time learning all the details of the crypto-algorithms. Typical mistakes you make using crypto in your products. How to avoid late night commits, but to code 'fast and boring' instead.

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Links to follow:

Boring crypto, Daniel J. Bernstein
https://cr.yp.to/talks/2015.10.05/slides-djb-20151005-a4.pdf

Why does cryptographic software fail?
https://pdos.csail.mit.edu/papers/cryptobugs:apsys14.pdf

API design for cryptography
https://2017.hack.lu/archive/2017/hacklu-crypto-api.pdf

Encrypting strings in Android: Let’s make better mistakes
https://tozny.com/blog/encrypting-strings-in-android-lets-make-better-mistakes/

Awesome crypto papers
https://github.com/pFarb/awesome-crypto-papers

12 And 1 Ideas How To Enhance Backend Data Security
https://www.cossacklabs.com/backend-data-security-modern-ideas.html

Attestation and Trusted Computing
https://courses.cs.washington.edu/courses/csep590/06wi/finalprojects/bare.pdf

Transcript

1. DON’T WASTE TIME ON
   LEARNING CRYPTOGRAPHY:
   BETTER USE IT PROPERLY
   #devexperience18 @vixentael
   

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2. @vixentael Product Engineer
   Feel free to reach me with
   security questions.
   I do check my inbox :)
   

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3. View Slide

4. We want to protect
   our users’ data
   

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5. We want
   developers to
   protect data
   

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6. We want to protect
   our users’ data
   HOW?
   We want
   developers to
   protect data
   

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7. WE HAVE USER DATA.
   WHAT SHALL WE DO?
   

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8. #devexperience18 @vixentael
   PROTECTING USER DATA:
   STEPS MISTAKES WE DO
   

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9. 1. DEFINING THE DATA SCOPE
   sensitive user data
   GDPR / HIPAA / PCI DSS
   tech data (keys, logs)
   #devexperience18 @vixentael
   

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10. 1. DEFINING THE DATA SCOPE
    sensitive user data
    GDPR / HIPAA / PCI DSS
    tech data (keys, logs)
    mistake 1.
    wrong scope definition
    #devexperience18 @vixentael
    

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11. 2. SELECTING ALGORITHM
    twofish
    sha1
    des
    md5
    #devexperience18 @vixentael
    

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12. twofish
    sha1
    des
    md5
    #owaspkyiv @vixentael
    2. SELECTING ALGORITHM
    mistake 2.
    bad algo selection
    

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13. THINGS TO DECIDE ON
    KEY LENGTH
    DATA SCOPE ALGORITHM
    #devexperience18 @vixentael
    

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14. https://wiki.openssl.org/index.php/EVP_Symmetric_Encryption_and_Decryption
    3. USING ALGORITHM
    #devexperience18 @vixentael
    

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15. https://wiki.openssl.org/index.php/EVP_Symmetric_Encryption_and_Decryption
    3. USING ALGORITHM
    #devexperience18 @vixentael
    

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16. https://wiki.openssl.org/index.php/EVP_Symmetric_Encryption_and_Decryption
    3. USING ALGORITHM
    mistake 3.
    wrong params
    #devexperience18 @vixentael
    

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17. THINGS TO DECIDE ON
    PADDING
    KEY LENGTH
    MODE
    DATA SCOPE ALGORITHM
    IV
    #devexperience18 @vixentael
    

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18. 4. KEY MANAGEMENT
    user password
    keys
    KDF
    #devexperience18 @vixentael
    

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19. 4. KEY MANAGEMENT
    user password
    keys
    KDF
    mistake 4.
    bad key management
    https://www.owasp.org/index.php/Key_Management_Cheat_Sheet #devexperience18 @vixentael
    

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20. THINGS TO DECIDE ON
    PADDING
    KEY LENGTH
    KEY ROTATION
    MODE KEY DERIVATION
    KEY STORAGE
    KEY EXCHANGE
    DATA SCOPE ALGORITHM
    IV
    KEY REVOCATION
    #devexperience18 @vixentael
    

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21. 5. INFRASTRUCTURE
    #devexperience18 @vixentael
    

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22. PADDING
    KEY LENGTH
    KEY ROTATION
    MODE KEY DERIVATION
    KEY STORAGE
    THINGS TO DECIDE ON
    KEY EXCHANGE
    BACKUPS
    PLATFORMS
    DATA SCOPE ALGORITHM
    IV
    KEY REVOCATION
    #devexperience18 @vixentael
    

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24. https://pdos.csail.mit.edu/papers/cryptobugs:apsys14.pdf
    269 CVEs
    from 2011-2014
    17%
    83%
    bugs inside crypto libs
    misuses of crypto libs
    by individual apps
    #devexperience18 @vixentael
    

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25. AS USERS WE WANT…
    more ciphers?
    #devexperience18 @vixentael
    

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26. AES
    DES
    3DES
    CBC
    CFB
    SEAL
    Salsa20
    RSA
    DSA
    #devexperience18 @vixentael
    

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27. AES
    DES
    3DES
    CBC
    CFB
    SEAL
    Salsa20
    RSA
    DSA
    OFB
    SHARK
    RC4
    DSS
    ECB CTR
    SEED
    Blowfish
    #devexperience18 @vixentael
    

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28. AES
    DES
    3DES
    CBC
    CFB
    SEAL
    Salsa20
    RSA
    DSA
    OFB
    Blowfish
    SHARK
    RC4
    DSS
    ECB CTR
    Twofish
    Camelia
    SEED
    Rabbit
    ECDSA
    #devexperience18 @vixentael
    

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29. AS USERS WE WANT…
    more ciphers!
    more vulnerabilities!
    more side channel attacks!
    more attacks!
    more constant time checks :)
    more protocols!
    more patches!
    #devexperience18 @vixentael
    

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30. View Slide

31. EXCITING, BUT FOR
    CRYPTO RESEARCHERS ONLY
    

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32. AS USERS WE WANT…
    more ciphers!
    BORING CRYPTO
    #devexperience18 @vixentael
    

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33. BORING CRYPTO
    — crypto that simply works, solidly
    resists attacks, never needs any
    upgrades
    https://cr.yp.to/talks/2015.10.05/slides-djb-20151005-a4.pdf
    Daniel J. Bernstein
    #devexperience18 @vixentael
    

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34. BORING CRYPTO
    PLUG & PLAY
    #devexperience18 @vixentael
    

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35. WHAT DO WE WANT?
    instead of adjusting
    our resources
    — SOLVE USE-CASES!
    

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36. WHAT DO WE WANT?
    — HIGH-LEVEL FUNCTIONS
    I want to store data securely
    I want to send data securely
    I want to verify data integrity
    #devexperience18 @vixentael
    

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37. WHAT DO WE WANT?
    store data securely
    send data securely
    verify data integrity
    key derivation
    key exchange
    key rotation
    sign/verify ephemeral keys
    encr / decr
    — HIGH-LEVEL FUNCTIONS
    #devexperience18 @vixentael
    

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38. NOBODY
    READS DOCS
    #devexperience18 @vixentael
    

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39. NOBODY
    READS DOCS
    “docs are for experts”
    “I just want to try”
    “gimme code!”
    #devexperience18 @vixentael
    

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40. 1. HOW TO START?
    pod try BoringSSL
    cmake -DANDROID_ABI=armeabi-v7a \
    -DCMAKE_TOOLCHAIN_FILE=../third_party/
    android-cmake/android.toolchain.cmake \
    -DANDROID_NATIVE_API_LEVEL=16 \
    -GNinja ..
    https://boringssl.googlesource.com/boringssl/+/HEAD/BUILDING.md #devexperience18 @vixentael
    

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41. easy, architecture-independent
    installation
    1. HOW TO START?
    #devexperience18 @vixentael
    

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42. 2. SUPPORTED PLATFORMS?
    *nix
    OSX
    web browsers embedded
    iOS
    Android
    Windows
    minimum expected:
    #devexperience18 @vixentael
    

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43. cross-platform is not an option anymore
    cross-platform is a must have
    2. SUPPORTED PLATFORMS?
    #devexperience18 @vixentael
    

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44. OPTIONS WE HAVE
    

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45. #owaspkyiv @vixentael
    HSM
    

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46. HARDWARE SECURITY MODULE
    key generation
    provides cryptoprocessing
    key storage
    portable
    #devexperience18 @vixentael
    

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47. #owaspkyiv @vixentael
    TRUSTED PLATFORM MODULE
    key management
    disk protection
    trust anchor
    built-in
    remote attestation
    provides cryptoprimitives
    

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48. HSM & TPM: PROS
    fast hardware crypto!
    trusted environment
    known security guarantees
    keys calculations
    #devexperience18 @vixentael
    

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49. HSM & TPM: CONS
    vendor lock / vendor trust
    bad for interactive encryption
    complicated to maintain
    (install, upgrade, support,
    not cross-platform)
    #devexperience18 @vixentael
    

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50. HSM & TPM: PRO & CONS
    HSM
    app
    plaintext
    data
    plaintext data is
    far away from
    the place it is used
    #devexperience18 @vixentael
    

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51. SOFTWARE CRYPTO SYSTEMS
    https://github.com/sobolevn/awesome-cryptography
    any kind of encryption
    plaintext data is closer
    to its usage
    cross-platform
    

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52. https://github.com/sobolevn/awesome-cryptography
    SOFTWARE CRYPTO SYSTEMS
    any kind of encryption
    plaintext data is closer
    to its usage
    cross-platform
    NO DEVICE TRUST
    

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53. WEBBROWSER CRYPTO: CONS
    DOM, XSS,
    NO CODE TRUST
    #devexperience18 @vixentael
    

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54. HSM/TPM + SOFTWARE CS
    keys calculations
    TPM /
    own
    software
    cross-platform
    take best from both
    #devexperience18 @vixentael
    HSM
    

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56. cross-platform
    easy to install
    easy to use
    USING CRYPTO SHOULD BE LIKE..
    audited
    open source
    time proven
    well-documented
    #devexperience18 @vixentael
    

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57. crypto-libraries
    crypto-systems
    boxed solutions
    FORM-FACTOR STAIRS
    

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58. #devexperience18 @vixentael
    

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59. 1. CRYPTO-LIBS
    implements single or multiple
    security functions
    #devexperience18 @vixentael
    https://github.com/sobolevn/awesome-cryptography
    

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60. 1. CRYPTO-LIBS
    libsodium
    themis
    https://github.com/sobolevn/awesome-cryptography
    implements single or multiple
    security functions
    keyczar
    noise
    #devexperience18 @vixentael
    

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61. EXAMPLE
    https://github.com/cossacklabs/themis/wiki/Python-Howto
    secure messaging with forward secrecy
    #devexperience18 @vixentael
    

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62. 2. CRYPTO-SYSTEMS
    combines security functions for
    solving exact use-case
    #devexperience18 @vixentael
    

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63. 2. CRYPTO-SYSTEMS
    axolotl
    hermes
    combines security functions for
    solving exact use-case
    SSL/TLS
    ZeroKit
    #devexperience18 @vixentael
    

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64. EXAMPLE
    https://github.com/cossacklabs/hermes-core/wiki/Python-tutorial
    data access control based on crypto-keys
    python docs/examples/python/hermes_client.py
    --id USER1
    --config=docs/examples/python/config.json
    --private_key USER1.priv
    --doc secretfile
    --read
    #devexperience18 @vixentael
    

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65. 3. BOXED SOLUTIONS
    unites crypto-systems and user
    functions for solving problems
    #devexperience18 @vixentael
    

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66. 3. BOXED SOLUTIONS
    truecrypt
    ssh
    acra
    vault
    unites crypto-systems and user
    functions for solving problems
    #devexperience18 @vixentael
    

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67. EXAMPLE
    https://github.com/cossacklabs/acra/wiki/Trying-Acra-with-Docker
    database proxy for encrypting / decrypting
    git clone https://github.com/cossacklabs/acra
    cd acra/docker
    docker-compose -f acra-pgsql-ssl-proxy.yml up -d
    #devexperience18 @vixentael
    

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68. CAN I SOLVE MY USE-CASE
    USING…
    boxed solutions
    

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69. CAN I SOLVE MY USE-CASE
    USING…
    crypto-libraries
    crypto-systems
    boxed solutions
    more pain
    

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70. CAN I SOLVE MY USE-CASE
    USING…
    crypto-libraries
    crypto-systems
    boxed solutions
    more pain
    even
    more pain
    

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71. https://www.cossacklabs.com/choose-your-ios-crypto.html
    

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72. THE WORLD DOESN’T HAVE
    A PROBLEM WITH
    NEW CRYPTO-ALGORITHMS.
    

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73. THE WORLD DOESN’T HAVE
    A PROBLEM WITH
    NEW CRYPTO-ALGORITHMS.
    PROBLEM IS THAT THEY ARE
    NOT BORING ENOUGH
    

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74. #devexperience18 @vixentael
    

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75. VS
    #devexperience18 @vixentael
    

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76. make the light
    controllable
    #devexperience18 @vixentael
    

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77. #devexperience18 @vixentael
    

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78. make the crypto
    security
    controllable
    #devexperience18 @vixentael
    

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79. make the crypto
    security
    controllable
    and booooring
    #devexperience18 @vixentael
    

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80. #owaspkyiv @vixentael
    

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81. LINKS 1
    Boring crypto, Daniel J. Bernstein
    https://cr.yp.to/talks/2015.10.05/slides-djb-20151005-a4.pdf
    Why does cryptographic software fail?
    https://pdos.csail.mit.edu/papers/cryptobugs:apsys14.pdf
    API design for cryptography
    https://2017.hack.lu/archive/2017/hacklu-crypto-api.pdf
    

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82. LINKS 2
    Encrypting strings in Android: Let’s make better mistakes
    https://tozny.com/blog/encrypting-strings-in-android-lets-make-better-mistakes/
    Awesome crypto papers
    https://github.com/pFarb/awesome-crypto-papers
    12 And 1 Ideas How To Enhance Backend Data Security
    https://www.cossacklabs.com/backend-data-security-modern-ideas.html
    Attestation and Trusted Computing
    https://courses.cs.washington.edu/courses/csep590/06wi/finalprojects/bare.pdf
    

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83. MY OTHER SECURITY SLIDES
    https://github.com/
    vixentael/my-talks
    …and more
    

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84. @vixentael Product Engineer
    Feel free to reach me with
    security questions.
    I do check my inbox :)
    

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