:- use_module(library(xmldsig)).(can be autoloaded)
- File holding the private key needed to sign
- String holding the password to op the private key.
The SignedDOM must be emitted using xml_write/3
xml_write_canonical/3. If xml_write/3
is used, the option
layout(false) is needed to avoid changing the layout of the
SignedInfo element and the signed DOM, which
will cause the signature to be invalid.