My TLS was broken

Transcript

1. My TLS is broken
   and probably yours too.
   

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2. My TLS was broken
   My TLS is broken
   My TLS was broken
   My TLS is broken
   My TLS was broken
   My TLS will be broken
   

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3. Part 1: The GreenLock
   

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4. HTTPS
   func main() {
   http.ListenAndServeTLS(":443",
   "server.crt", "server.key", nil)
   }
   

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5. Picture or it didn’t happen
   

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6. HTTPS Server
   

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7. Part 2: TCP TLS
   

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8. TCP TLS Server
   func main() {
   cer, err := tls.LoadX509KeyPair("server.crt", "server.key")
   config := &tls.Config{Certificates: []tls.Certificate{cer}}
   ln , err := tls.Listen("tcp", ":443", config)
   conn, err := ln.Accept()
   go handleConnection(conn)
   }
   

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9. TLS Client
   func main() {
   conf := &tls.Config{//InsecureSkipVerify: true}
   conn, err := tls.Dial("tcp", "ldap.ha.tsengine.io:847", conf)
   n, err := conn.Write([]byte("hello\n"))
   buf := make([]byte, 100)
   n, err = conn.Read(buf)
   log.Println(n, err)
   }
   

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10. Server Client TCP
    

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11. Part 3: Opportunistic TLS
    

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12. func main() {
    listener, _ := net.Listen("tcp", "127.0.0.1:8000")
    conn, err := listener.Accept()
    bytesRead, err := conn.Read(...)
    if string(buffer[0:bytesRead]) == STARTTLS {
    conn := tls.Server(unenc_conn, &config)
    var buffer = make([]byte, 1024)
    conn.Handshake()
    ...
    }
    }
    TLS Client
    

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13. Part 4
    

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14. TLS Client Auth Handshake
    

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15. TLS Exchange
    

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16. Certificates
    

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17. meson10@DESKTOP-S7PEUGG:~$ openssl x509 -in <(openssl s_client -connect
    wikipedia.com:443 2>&1 < /dev/null | sed -n '/-----BEGIN/,/-----END/p') -text
    Certificate:
    Data:
    Version: 3 (0x2)
    Serial Number:
    08:30:94:62:d1:fe:a6:0a:e0:ba:bf:f5:ef:8b:c5:45
    Validity
    Not Before: Dec 21 00:00:00 2017 GMT
    Not After : Jan 24 12:00:00 2019 GMT
    X509v3 CRL Distribution Points:
    Full Name:
    URI:http://crl3.digicert.com/sha2-ha-server-g6.crl
    Full Name:
    URI:http://crl4.digicert.com/sha2-ha-server-g6.crl
    Authority Information Access:
    OCSP - URI:http://ocsp.digicert.com
    

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18. Sharing is not Caring,
    Your parents have been lying.
    

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19. Part 5: Client Authentication
    

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20. Client Authentication
    

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21. Why is Client Auth needed?
    

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22. But we use API Keys
    

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23. Client Certificate
    Certificate:
    Issuer: C = IN, ST = MH, L = Pune, OU = TS Sre Certificate
    Authority, CN = TS Sre CA
    Validity
    Not Before: Jan 18 06:53:00 2019 GMT
    Not After : Jan 17 06:53:00 2024 GMT
    Subject: C = IN, ST = MH, L = Pune, OU = TrustingSocial, CN =
    tls_demo_client
    Authority Information Access:
    OCSP - URI:http://ca.ha.tsengine.io:7889
    CA Issuers -
    URI:http://ca.ha.tsengine.io:1500/intermediate/intermediate.crt
    X509v3 CRL Distribution Points:
    Full Name:
    URI:http://ca.ha.tsengine.io:6688/api/v1/cfssl/crl
    

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24. certificate, err := tls.LoadX509KeyPair(cert, key)
    tlsConfig := &tls.Config{
    ServerName: "my-server",
    ClientAuth: tls.RequireAndVerifyClientCert,
    Certificates: []tls.Certificate{certificate},
    }
    ln, err := tls.Listen("tcp", ":443", config)
    conn, err := ln.Accept()
    go handleConnection(conn)
    Accepting Client Certs
    

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25. Deprecation of Internal &
    Reserved IP Addresses
    Circa 2012
    

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26. Part 6: PKI
    

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27. PKI Infrastructure
    

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28. certPool := x509.NewCertPool()
    b, err := ioutil.ReadFile(rootPath)
    certPool.AppendCertsFromPEM(bs)
    tlsConfig := &tls.Config{
    ServerName: "my-server",
    ClientAuth: tls.RequireAndVerifyClientCert,
    Certificates: []tls.Certificate{certificate},
    ClientCAs: certPool,
    }
    Accepting Client Certs
    

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29. certificate, err := tls.LoadX509KeyPair(cert, key)
    certPool := x509.NewCertPool()
    b, err := ioutil.ReadFile(rootPath)
    certPool.AppendCertsFromPEM(bs)
    tlsConfig := &tls.Config{
    Certificates: []tls.Certificate{certificate},
    RootCAs: certPool,
    }
    Accepting Server Certs
    

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30. Part 7: Take it Back
    

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31. How do you take-back a Cert?
    

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32. CRL
    

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33. meson10@DESKTOP-S7PEUGG:~$ openssl x509 -in <(openssl s_client -connect
    wikipedia.com:443 2>&1 < /dev/null | sed -n '/-----BEGIN/,/-----END/p') -text
    Certificate:
    Data:
    Version: 3 (0x2)
    Serial Number:
    08:30:94:62:d1:fe:a6:0a:e0:ba:bf:f5:ef:8b:c5:45
    Validity
    Not Before: Dec 21 00:00:00 2017 GMT
    Not After : Jan 24 12:00:00 2019 GMT
    X509v3 CRL Distribution Points:
    Full Name:
    URI:http://crl3.digicert.com/sha2-ha-server-g6.crl
    Authority Information Access:
    OCSP - URI:http://ocsp.digicert.com
    

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34. CRL
    

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35. CRL
    

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36. Problems with CRL
    

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37. OCSP
    

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38. meson10@DESKTOP-S7PEUGG:~$ openssl x509 -in <(openssl s_client -connect
    wikipedia.com:443 2>&1 < /dev/null | sed -n '/-----BEGIN/,/-----END/p') -text
    Certificate:
    Data:
    Version: 3 (0x2)
    Serial Number:
    08:30:94:62:d1:fe:a6:0a:e0:ba:bf:f5:ef:8b:c5:45
    Validity
    Not Before: Dec 21 00:00:00 2017 GMT
    Not After : Jan 24 12:00:00 2019 GMT
    X509v3 CRL Distribution Points:
    Full Name:
    URI:http://crl3.digicert.com/sha2-ha-server-g6.crl
    Authority Information Access:
    OCSP - URI:http://ocsp.digicert.com
    

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39. OCSP Flow
    

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40. - Server Down?
    - DDOS CA
    - Privacy Compromise
    OCSP Challenges
    

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41. Soft Fail
    

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42. Soft Fail: Firefox
    

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43. Soft Fail: Chrome
    

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44. Hard Fail?
    

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45. What’s the most
    fragile thing in
    the Universe?
    a) Silence
    b) Taylor Swift’s heart.
    c) Neymar’s Shin
    d) Internet Security
    

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46. Part 7
    

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47. Why do you revoke keys?
    

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48. https://github.com/indutny/heartbleed
    

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49. cert, err := x509.ParseCertificate(cert)
    // ok := callOCSPServer(cert)
    if !ok {
    // Certificate is revoked
    }
    tlsConfig := &tls.Config{
    ServerName: "my-server",
    ClientAuth: tls.RequireAndVerifyClientCert,
    Certificates: []tls.Certificate{certificate},
    ClientCAs: certPool,
    VerifyPeerCertificate: certValidator,
    }
    Accepting Client Certs
    

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50. Part 8
    

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51. CAtoolkit
    http:/
    /github.com/tsocial/ca
    toolkit
    

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52. Maybe, Security is just a
    feeling?
    

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53. xps:~$ whoami
    Piyush Verma
    Site Reliability Engineering
    Trusting Social
    Twitter: meson10
    

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