Make DTLS cipher suite configurable

[hrosa]

Users should be able to configure DTLS cipher suite in RMS configuration file.

[hrosa]

Naming convention must follow https://docs.oracle.com/javase/8/docs/technotes/guides/security/StandardNames.html

[ghjansen]

@hrosa I used the JSSE Cipher Suite Names naming convention as described in https://docs.oracle.com/javase/8/docs/technotes/guides/security/StandardNames.html#ciphersuites since it appears to be the same convention used in BoucyCastle. Also, created two additional parameters to inform certificate and key paths as discussed previously and described by issue #257 .

The configuration is not used by the TlsServer yet since im not sure this is the correct/intended format. Please, could you take a look in the commit 25e081c and share your thoughts? I can revert my commit and fix what is needed. Thanks!

[deruelle]

@ghjansen can this take multiple ciphers separated by comma ?
I would say don't block on @hrosa until he is back. Wire it up and make tests with Chrome to ensure what you did is working end to end and the right cipher is negotiated based on what was provided in configuration.

[ghjansen]

Thanks @deruelle thats exactly my point, so this field should accept multiple values not only single ones, right? I can make it this way, yes. As it is, only one value is allowed.

I was planning to anticipate something in RestComm/Restcomm-Connect#1304, RestComm/Restcomm-Connect#49 and #228 as we discussed, so i won't block.

[deruelle]

@ghjansen yes, it needs to allow multiple values. It's a list of cipher suite accepted. In restcomm we use
TLS_RSA_WITH_3DES_EDE_CBC_SHA,TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,TLS_RSA_WITH_AES_128_CBC_SHA256,TLS_RSA_WITH_AES_128_CBC_SHA,TLS_RSA_WITH_AES_256_CBC_SHA256,TLS_RSA_WITH_AES_256_CBC_SHA by example

[deruelle]

@ghjansen the list of next issues sounds good to me once we are done with this one or absolutely need @hrosa input

[hrosa]

@ghjansen let's keep things separated. You have two tickets open: this one addresses cipher configuration while #257 addresses certificates configuration.

Let's focus on cipher configuration for now and get something working.

From my point of view the configuration file should follow the following format:

<dtls>
    <minVersion>1.0</minVersion>
    <maxVersion>1.2</maxVersion>
    <cipherSuite> cipherA,cipherB,...,cipherN</cipherSuite>
    <certificates>
        <certificate path="/path/to/certA.pem" key="/path/to/keyA.pem">
        <certificate path="/path/to/certB.pem" key="/path/to/keyB.pem">
    <certificates>
</dtls>

That being said, re-work your commit and get the following working.

<dtls>
    <cipherSuite> cipherA,cipherB,...,cipherN</cipherSuite>
</dtls>

Once this is done, make a PR so I can review and merge.