An Introduction to PASETO Tokens

JSON Web Tokens (JWTs) have become ubiquitous in the web authentication landscape over the last four years. In this talk, I'll introduce you to their successor: PASETO tokens (platform agnostic security tokens).

PASETO takes the best parts of the JWT spec and removes the rest. PASETO is a much simpler, more secure, and easier to use version of the JWT spec that makes cryptographers happy reduces risk for developers like you.

In this talk you'll learn what PASETO tokens are, how they work, and how to use them in your applications.

Transcript

1. @rdegges @oktadev
   PASETO Tokens
   An Introduction to
   platform agnostic security tokens
   

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2. @rdegges @oktadev
   Chief Hacker @okta
   python/js/go hacker
   builder
   open source
   author
   Hi, I'm Randall.
   

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3. @rdegges @oktadev
   What's PASETO?
   P
   {
   "id": "a5db284d-d22c-4a3d-b67e-60776fc24526",
   "email": "r@rdegges.com",
   "permissions": [
   "download:file-a.mp4",
   "download:file-b.mp4",
   "download:file-c.mp4"
   ]
   }
   Randall Degges
   PASETOs are always
   authenticated.
   

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4. @rdegges @oktadev
   What are cryptographic signatures?
   Greetings,
   I am writing to inform you
   that you are the great
   grandson of a very wealthy
   king.
   I've been attempting to
   contact you to transfer
   your inheritance. Please
   send me your bank
   account details so I can
   initiate the transfer ASAP.
   Sincerely yours,
   Randall Degges
   I know who Randall is. I know what
   his signature looks like. I trust him.
   Therefore, I trust this information.
   

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5. @rdegges @oktadev
   What are PASETOs for?
   Proving that JSON
   data can be trusted.
   {
   "name": "Randall Degges",
   "height": "6'0",
   "eyeColor": "brown"
   }
   single-use only
   short duration
   P
   

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6. @rdegges @oktadev
   What does a PASETO look like?
   P
   v2.public.eyJpZCI6ICJjNDQ1NDY1Mi05NWExLTQ2MzktODA0Y
   y0yZjc2MTVhNGMwMjciLCAibmFtZSI6ICJSYW5kYWxsIERlZ2dl
   cyIsICJleHAiOiAiMjAxOS0xMC0xMFQxMTowNDozNS0wNzowMCJ
   9rUy35ian_44WAlMLVi5Wk4GGvDlmCpEWkldn1CH3RgLfo-VUWm
   xC9EPTBY8l0uoomavACbAIoo1OiGVNMew1Bw.eyJraWQiOiAiMT
   IzNDUifQ
   base64-encoded
   URL safe!
   

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7. @rdegges @oktadev
   What does a PASETO look like?
   P
   v2.public.eyJpZCI6ICJjNDQ1NDY1Mi05NWExLTQ2MzktODA0Y
   y0yZjc2MTVhNGMwMjciLCAibmFtZSI6ICJSYW5kYWxsIERlZ2dl
   cyIsICJleHAiOiAiMjAxOS0xMC0xMFQxMTowNDozNS0wNzowMCJ
   9rUy35ian_44WAlMLVi5Wk4GGvDlmCpEWkldn1CH3RgLfo-VUWm
   xC9EPTBY8l0uoomavACbAIoo1OiGVNMew1Bw.eyJraWQiOiAiMT
   IzNDUifQ
   version
   

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8. @rdegges @oktadev
   What does a PASETO look like?
   P
   v2.public.eyJpZCI6ICJjNDQ1NDY1Mi05NWExLTQ2MzktODA0Y
   y0yZjc2MTVhNGMwMjciLCAibmFtZSI6ICJSYW5kYWxsIERlZ2dl
   cyIsICJleHAiOiAiMjAxOS0xMC0xMFQxMTowNDozNS0wNzowMCJ
   9rUy35ian_44WAlMLVi5Wk4GGvDlmCpEWkldn1CH3RgLfo-VUWm
   xC9EPTBY8l0uoomavACbAIoo1OiGVNMew1Bw.eyJraWQiOiAiMT
   IzNDUifQ
   version
   purpose
   

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9. @rdegges @oktadev
   What does a PASETO look like?
   P
   v2.public.eyJpZCI6ICJjNDQ1NDY1Mi05NWExLTQ2MzktODA0Y
   y0yZjc2MTVhNGMwMjciLCAibmFtZSI6ICJSYW5kYWxsIERlZ2dl
   cyIsICJleHAiOiAiMjAxOS0xMC0xMFQxMTowNDozNS0wNzowMCJ
   9rUy35ian_44WAlMLVi5Wk4GGvDlmCpEWkldn1CH3RgLfo-VUWm
   xC9EPTBY8l0uoomavACbAIoo1OiGVNMew1Bw.eyJraWQiOiAiMT
   IzNDUifQ
   version
   purpose
   payload
   

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10. @rdegges @oktadev
    What does a PASETO look like?
    P
    v2.public.eyJpZCI6ICJjNDQ1NDY1Mi05NWExLTQ2MzktODA0Y
    y0yZjc2MTVhNGMwMjciLCAibmFtZSI6ICJSYW5kYWxsIERlZ2dl
    cyIsICJleHAiOiAiMjAxOS0xMC0xMFQxMTowNDozNS0wNzowMCJ
    9rUy35ian_44WAlMLVi5Wk4GGvDlmCpEWkldn1CH3RgLfo-VUWm
    xC9EPTBY8l0uoomavACbAIoo1OiGVNMew1Bw.eyJraWQiOiAiMT
    IzNDUifQ
    version
    purpose
    payload footer
    

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11. @rdegges @oktadev
    What's inside a PASETO?
    P
    {
    "id": "a5db284d-d22c-4a3d-b67e-60776fc24526",
    "email": "r@rdegges.com",
    "permissions": [
    "download:file-a.mp4",
    "download:file-b.mp4",
    "download:file-c.mp4"
    ]
    }
    claims
    

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12. @rdegges @oktadev
    key name type example
    iss Issuer string {"iss": "okta.com"}
    sub Subject string {"sub": "test"}
    aud Audience string {"aud": "okta.com"}
    exp Expiration DateTime {"exp": "2019-10-31T00:00:00+00:00"}
    nbf Not Before DateTime {"nbf": "2019-10-31T00:00:00+00:00"}
    iat Issued At DateTime {"iat": "2019-10-31T00:00:00+00:00"}
    jti Token ID string {"jti": "ac478bc0-c73a-4a2c-8f00-186456cf8d88")
    kid Key-ID string {"kid": "stored in footer"}
    Who created the token?
    When does the token expire?
    When was the token created?
    

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13. @rdegges @oktadev
    What are the different types of PASETOs?
    P P
    local public
    symmetric shared key
    simple
    asymmetric
    public key
    complicated
    encrypted
    not encrypted
    

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14. @rdegges @oktadev
    How do local PASETOs work?
    v2.local.vB7daJlQOL5sY8mQa_FWb6ZYbkNi8yeRqI-DCFNEPTYEu7ItQH
    MMM5jzD_fw-G7l-AXJRBj3E9jxx9-JS5eG436WGUn03zYp2nuV3PVqppEyR
    P9LoZ1TTBREhR182NRcNYqUkM8FfazWegWcLc1gSzFXx0Kge4U7XHtAlliT
    rR8p09hH6qVpqAsgMdp00ao66JX_mxlEjkL3y784CoAK-gyy_ZZ1WzAvYAj
    QApl859RxnB9uLMpb-VURmetmrw9sC_Iw27to46ulTcMxx_KoSBem9eSG5M
    4bvNQC5YFeDLIM2HXDf35YIo50.eyJraWQiOiAiMTIzNDUifQ
    secret_key
    { json }
    fuck
    The secret_key is needed to
    both encrypt and decrypt
    the PASETO.
    

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15. @rdegges @oktadev
    How do I use local PASETOs?
    www.
    P
    secret_key
    dl.
    {
    "purchaseID": "1234567",
    "permissions": [
    "download:video1.mp4",
    "download:video2.mp4",
    "download:video3.mp4"
    ]
    }
    ?token=v2.local.xxx&
    file=video1.mp4
    - Parse URL params
    - Decrypt token
    - Verify purchaseID
    - Verify permissions
    - Stream file to user
    video1.mp4
    I want to download
    video1.mp4.
    secret_key
    - Validate request
    - Generate PASETO
    - Redirect
    

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16. @rdegges @oktadev
    How do public PASETOs work?
    v2.public.vB7daJlQOL5sY8mQa_FWb6ZYbkNi8yeRqI-DCFNEPTYEu7ItQ
    HMMM5jzD_fw-G7l-AXJRBj3E9jxx9-JS5eG436WGUn03zYp2nuV3PVqppEy
    RP9LoZ1TTBREhR182NRcNYqUkM8FfazWegWcLc1gSzFXx0Kge4U7XHtAlli
    TrR8p09hH6qVpqAsgMdp00ao66JX_mxlEjkL3y784CoAK-gyy_ZZ1WzAvYA
    jQApl859RxnB9uLMpb-VURmetmrw9sC_Iw27to46ulTcMxx_KoSBem9eSG5
    M4bvNQC5YFeDLIM2HXDf35YIo50.eyJraWQiOiAiMTIzNDUifQ
    private key
    { json }
    I can see the data.
    The private key is needed to
    create the PASETO. The
    public key is need to
    validate the PASETO.
    public key
    

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17. @rdegges @oktadev
    How do I use public PASETOs?
    website
    P
    public_key
    authorization
    server
    private_key
    public_key
    {
    "userID": "1234567"
    }
    I'd like to log in.
    - Authenticate the user
    - Generate a PASETO
    - Redirect the user back to
    the website
    ?token=v2.public.xxx
    - Parse the token out of the URL
    - Validate the token
    - Create a secure session using
    server-side session management
    

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18. @rdegges @oktadev
    Why are PASETOs better than JWTs?
    

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19. @rdegges @oktadev
    What's wrong with JWTs?
    Allows poor cryptography choices
    - RSA w/ PKCS #1v1.5 padding
    - RSA w/ OAEP Padding
    - Elliptic Curve Diffie-Hellman (ECDH)
    using Weierstrass curves
    - AES-GCM
    They're widely misused.
    Force implementations to
    strictly process the alg header.
    This causes forgery issues.
    Vulnerable to a padding
    oracle attack.
    Cryptographers recommend
    migrating away from RSA.
    Introduces risk of invalid-curve attacks
    that allow attackers to steal your secret
    keys.
    This is the wrong type of
    cryptography entirely. Using
    symmetric encryption when
    asymetric is needed.
    

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20. @rdegges @oktadev
    Try PASETO!
    P paseto.io
    read the RFC
    find developer libraries
    discover articles
    

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21. @rdegges @oktadev
    Thank You
    rdegges.com
    developer.okta.com
    

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