SSL All The Things (DjangoCon US 2016)

My talk from DjangoCon US 2016.

Speaker notes / blog post: https://markusholtermann.eu/2016/07/ssl-all-the-things/

Transcript

1. SSL All The Things Django and SSL
2. Markus Holtermann Senior Software Engineer at LaterPay Django Core Developer @m_holtermann • github.com/MarkusH • markusholtermann.eu
3. EASY MICROPAYMENTS FOR YOUR FAVORITE CONTENT USE NOW, PAY LATER. @laterpay • github.com/laterpay • laterpay.net W e are hiring
5. Disclaimer
6. What is SSL / TLS?
7. Webserver configuration
8. Apache 2 / httpd <VirtualHost *:443> ServerName example.com SSLEngine on # Details at https://cipherli.st/ SSLCipherSuite EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH SSLHonorCipherOrder on SSLProtocol all -SSLv3 SSLCertificateFile /etc/nginx/ssl/example.com.crt SSLCertificateKeyFile /etc/nginx/ssl/example.com.key SSLOpenSSLConfCmd DHParameters "/etc/nginx/ssl/example.com.dh" </VirtualHost>
9. host { listen [::]:443 ssl; server_name example.com; # Details at https://cipherli.st/ ssl_ciphers EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH; ssl_prefer_server_ciphers on; ssl_protocols TLSv1 TLSv1.1 TLSv1.2; ssl_certificate /etc/nginx/ssl/example.com.crt; ssl_certificate_key /etc/nginx/ssl/example.com.key; ssl_dhparam /etc/nginx/ssl/example.com.dh; } Nginx
10. What is Let’s Encrypt ?
11. Trust Store Intermediate CA 1 Intermediate CA 2 Root CA 1 Root CA 2 Intermediate CA 3 Certs Certs Certs Root CA 3
12. What is Let’s Encrypt ?
13. The ACME Process Account Key Certificate Key Certificate Signing Request
14. The ACME Process new-authz Challenges Certificate Signing Request new-cert Certificate Retrieve Certificate Write Challenges Check challenge new-reg Public Account Key Account Key Certificate Key Certificate Signing Request
15. Apache 2 / httpd <VirtualHost *:80> ServerName example.com Redirect / https://example.com/ Alias "/.well-known/acme-challenge/" "/srv/http/acme-challenges/" <Directory "/srv/http/acme-challenges"> AllowOverride None Options None Require all granted </Directory> </VirtualHost>
16. host { listen [::]:80; server_name example.com; location /.well-known/acme-challenge/ { alias /srv/http/acme-challenges/; try_files $uri =404; } location / { return 301 https://example.com$request_uri; } } Nginx
17. How to use Let’s Encrypt ?
18. python3 /etc/acme-tiny/acme-tiny.py \ --account-key "/etc/acme-tiny/account.key" \ --csr "/etc/acme-tiny/example.com.csr" \ --acme-dir "/srv/www/acme-challenges" \ --output "/etc/nginx/ssl/example.com.crt" \ --combine "https://letsencrypt.org/certs/lets-encrypt-x3-cross-signed.pem" Using Let’s Encrypt
19. Adjusting Django • Use “secure” cookies — Set CSRF_COOKIE_SECURE and SESSION_COOKIE_SECURE to True import os CSRF_COOKIE_SECURE = os.getenv(‘SECURE_COOKIES’) == ‘yes’ SESSION_COOKIE_SECURE = os.getenv(‘SECURE_COOKIES’) == ‘yes’ • https://docs.djangoproject.com/en/dev/topics/security/
20. What I didn’t cover ... … but want to mention
21. Certificate Revocation
22. Changing the Account Key
23. HSTS HTTP Strict Transport Security
24. HPKP HTTP Public Key Pinning
25. Usage for other services
26. Things that could go wrong An incomplete list
27. HSTS / HPKP
28. Leaked Keys
29. Resource Usage
30. Sources • https://cipherli.st/ • https://www.ssllabs.com/ssltest/index.html • https://hynek.me/talks/tls/ • https://ssldecoder.org/ • https://securityheaders.io/ • https://github.com/ietf-wg-acme/acme/blob/bf34c2a/draft-ietf-acme-acme.md • https://security.googleblog.com/2016/07/experimenting-with-post-quantum.html
31. Thanks @m_holtermann • github.com/MarkusH • markusholtermann.eu • laterpay.net Questions?