Certificates in AARQ

By enemy235 , 26 August, 2025
Forums
Gurux.DLMS

Hello,
I want to ask, if sending a certificate in AARQ is supported in latest version (Java or .Net).

There is a year old topic about it, that it will be in next version (https://www.gurux.fi/comment/28057)

Thank you.

Kurumi

11 months 1 week ago

Hi,

Yes, this is supported in Java and Net, but this is not implemented in GXDLMSDirector.
Set the ClientPublicKeyCertificate to the client and it's sent with AARQ.

BR,
Mikko

enemy235

11 months 1 week ago

Thank you, I will try that.

I'm working with a new meter, that needs the certificate in AARQ and also it needs digital signature on all messages. I was going through the code and I don't know, if/how it can be enabled. Is digital signatures of all mesages implemented in Java version?

Kurumi

11 months 1 week ago

Hi,

Yes, digital signature is supported in Java.

You need to set the private and public keys to the client's KeyAgreementKeyPair
and they are used after the connection is established.

Somethiing like this:

//Load the client's private key.
GXPkcs8 key = GXPkcs8.load(path);
// Load the server's public key.
GXx509Certificate cert = GXx509Certificate.load(path);
dlms.getCiphering().setKeyAgreementKeyPair(new KeyPair(cert.getPublicKey(), key.getPrivateKey()));

BR,
Mikko