Restrict cipher suites on JRE level

9
votes

Our Java application exposes a lot of different interfaces (SMTP, FTP, HTTP), secured by SSL/TLS. The goal now is to limit cipher suites allowed on these interfaces to include only "strong" ones. I already have a list and it's clear how to make it working for a particular socket

socket.setEnabledCipherSuites(ENABLED_SECURE_CIPHER_SUITES);

or for Tomcat connector

 <Connector port="443" ciphers="..."/>

The problem is that there are already 5 places in the application where I should apply this limitation manualy. Common SocketFactory does not seem to help, as it's not always feasible to supply custom SocketFactory to third-party API or framework. Is it possible to somehow introduce this limitation on JRE level, e.g. with JCE providers configuration or policy file?

JRE: Oracle JRE 1.7.0_17

1
javajce
Define 'strong'. Java already restricts the enabled cipher suites. Are you aware of the Networking Properties? – user207421
This question is not about the strength of a particular ciphers. I have a fixed list of allowed ciphers and I can't change it. For example, RC4 is not allowed at all. So, default Java restrictions aren't enough. I also checked networking properties, but found no properties related to cipher suites. – Jk1
See the JSSE Reference Guide. – user207421

1 Answers

10
votes

Well, I managed to get that working. Thanks to EJP for pointing in the right direction. Since Java 1.7 there are two additional properties in $JRE_HOME/lib/security/java.security:

jdk.certpath.disabledAlgorithms=MD2

Controls algorithms for certification path building and validation.

jdk.tls.disabledAlgorithms=MD5, SHA1, RC4, RSA keySize < 1024

JVM-wide algorithm restrictions for SSL/TLS processing, the one I was looking for. Notation is quite obvious here; it's possible to disallow certain algorithms or limit key sizes. Both properties are supported in Oracle JRE 7, Open JRE 7 and (surprisingly) IBM Java v7