A gentle guide to SSL, how it works, how it works with Java and how to debug SSL connections

1. SSL in a Nutshell Just enough to be dangerous . . . . .

2. In the kingdom of the blind, the one eyed man is king (In other words I am not an expert – I just play one on TV!) This is all relatively introductory information Expectation setting

3. What is SSL? Certificates How does SSL work? How we use SSL? SSL & Java Configuration Debugging Resources Agenda

4. SSL = Secure Socket Layer TLS = Transport Layer Security is the new name A cryptographic protocol to provide secure communication over networks (such as Internet) Protocol provides two of the three key aspects for Security Confidentiality (Encryption) Authentication (you are who you say you are) Authorization (What you can do – controlled by your app – not the protocol) What is SSL?

5. What is a Certificate? A signed digital certificate is an industry-standard means of verifying the authenticity of an entity, such as a server, client, or application. To ensure maximum security, a certificate is issued by a third-party certificate authority (CA) e.g. Verisign But first this . . . .

6. Creation date: Jul 28, 2010 Entry type: PrivateKeyEntry Certificate chain length: 1 Certificate[1]: Owner: CN=some.url, OU=Services, O=Nokia, L=Burlington, ST=Massachusetts, C=US Issuer: OU=www.verisign.com/CPS Incorp.by Ref. LIABILITY LTD.(c)97 VeriSign, OU=VeriSign International Server CA - Class 3, OU="VeriSign, Inc.", O=VeriSign Trust Network Serial number: 7c391cdfaf10822ce338c3eb925f77bc Valid from: Mon Apr 12 00:00:00 UTC 2010 until: Tue Apr 12 23:59:59 UTC 2011 Certificate fingerprints: MD5: 06:5C:45:66:C5:28:77:48:E6:58:D9:FB:C5:06:41:1C SHA1: 74:4B:A8:3D:A7:BF:57:30:4E:23:B5:21:4C:2E:9B:8B:27:5F:9E:A5 Signature algorithm name: SHA1withRSA Version: 3 And more stuff . . . . What does a cert look like? Ours.

8. Client picks a random number, encrypts that (with server’s public key) and sends it to server. Only server can decrypt it (using it’s private key) Now they both have a shared secret (the random number) From the random number, both parties generate key material for encryption and decryption. This concludes the handshake Secured connection, which is encrypted and decrypted with the key material until the connection closes How does SSL work? (cont.)

9. In the One-way example the client just verified the server is who they say they are? Example: Login to your bank? But how does your bank know YOU are who you say you are? Typically a login/password 2 Way SSL achieves the same “Mutual Authentication” by having both sides use Certs 2-Way SSL

10. 2-Way SSL

11. It is a Widespread Standard and is rock solid – no major hacking stories / events. But nothing is impervious Why SSL?

12. We use SSL to talk with aggregators Outbound: TO the aggregator Inbound: FROM the aggregator (the callback) We also use SSL in communication with folks upstream but dedicated fiber With Dev certs (we trust them right!) And we add Digital Signing . . . . Just in case? How do we use SSL?

13. JSSE = Java Secure Socket Extension is the default Java package Was optional package before JDK 1.4. Now it’s bundled in the JDK. Either way it’s not easy to use We use Apache HTTP Client - it’s still REALLY hard (not!) HttpClient httpclient = new HttpClient(); GetMethod httpget = new GetMethod("https://www.verisign.com/"); try { httpclient.executeMethod(httpget); System.out.println(httpget.getStatusLine()); } finally { httpget.releaseConnection(); } SSL using Java

14. The hard part is acquiring and managing the keys and certs Procuring a cert is described elsewhere Keystore Contains our private key and private certificate Created from scratch Truststore Used to contain Self-Signed Certs from Aggregators Copied from Java’s own cacerts (to handle the case where certs are signed by the CA) The hard part . . . . .

15. Keytool ships with Java Show Keys & Certs in Keystore keytool -list -v -keystore keystore -storepass changeit Show Certs in the Truststore keytool -list -v -keystore cacerts -storepass changeit Keystore / truststore: how to . . .

16. SSL does not have to be handled (“offloaded”) by Jboss/Tomcat It can be offloaded by Apache Web Server It can be offloaded by Load Balancer Architecture

17. IMPORTANT NOTE: Not addressed here – this is up to your application Authorization

18. Typical Exceptions if . . . Can’t find keystore / truststore Our private key is missing from keystore Whitelisting error (not really SSL) Debugging: What to look for

19. -Djavax.net.debug=all Debugging Tools #1

20. Use “wget” to unit test your key/certs (one-way!) e.g. to test wget -d -v --certificate=/somecrt --post-data ‘SOAP STUFF GOES HERE' --private-key=/somekey https://someurl.com Debugging tools #2: wget

21. Resolving somestage.com... XXX.242.50.144 Caching somestage.com => XXX.242.50.144 Connecting to somestage.com|XXX.242.50.144|:443... connected. Created socket 3. Releasing 0x000000001b0a5e70 (new refcount 1). Initiating SSL handshake. Handshake successful; connected socket 3 to SSL handle 0x000000001b10ee40 certificate: subject: /C=DK/postalCode=9210/ST=Aalborg/L=Aalborg SC398/streetAddress=Indkildevej 6E/O=TBD/OU=TBD/OU=Issued through TBD Manager/OU=Comodo PremiumSSL Legacy Wildcard/CN=*.somestag.com issuer: /C=GB/ST=Greater Manchester/L=Salford/O=Comodo CA Limited/CN=AAA Certificate Services X509 certificate successfully verified and matches host somestage.com ---request begin--- POST /thepath HTTP/1.0 . . . . . ---response begin--- HTTP/1.1 200 OK Date: Fri, 13 Aug 2010 16:27:31 GMT Server: Apache/1.3.33 (Debian GNU/Linux) PHP/4.3.10-15 mod_ssl/2.8.22 OpenSSL/0.9.7e wget Output

22. On most linux boxes Tcpdump Monitors traffic e.g. Monitor port 443 tcpdump -i eth0 -v dst port 443 Wireshark Also monitors traffic (but a bit nicer UI) http://www.wireshark.org/ Debugging tools #3: tcpdump etc.

23. You shouldn’t need to go here . . . But if you do Bryan, Derrick, Pete and Frank can assist Basically there are config files and they point to the usual suspects (Certs, Keys etc.) e.g. SSLVerifyClient require SSLVerifyDepth 10 SSLCertificateFile /etc/httpd/conf/ssl.crt/somecert SSLCertificateKeyFile /etc/httpd/conf/ssl.key/somekey Apache HTTP Server and SSL

24. At a high-level SSL is pretty straight-forward But the devil is in the details – keystores / truststores, apache configuration, different aggregator environments . . . . Plus add in server white listing . . .. When you hit a problem with SSL – first don’t panic! Check your configuration (run.conf, keystore/truststore, apache settings – if appropriate). We are here to help . . . Summary

25. JSSE Reference Guide (for JDK 6) http://download.oracle.com/javase/6/docs/technotes/guides/security/jsse/JSSERefGuide.html http://download.oracle.com/javase/6/docs/technotes/guides/security/jsse/ReadDebug.html Java Resources