<oXygen/> includes a tool for the creation and checking of digital signatures for both enveloped and detached signatures. The enveloped signatures are stored in the signed document, while the detached ones are stored in a separate file.
To sign a document you need to import your private key in a key store of type JKS or PCKS12. If you already have a Java source signing code certificate, you can use it from <oXygen/> to sign your documents. If you are using Microsoft Authenticode, check the documentation provided by the issuer of your certificate for instructions regarding the conversion to one of the above keystore types.
It is also possible to transform an XML document into the canonical form, save it and then use other signing tool if you do not have a certificate that can be converted to the supported formats.