DDSSEC11 — EndpointSecurity's is_payload_protected is Insufficient

Current version of the specification defines is_payload_protected EndpointSecurity attribute. While this is useful for letting the DDS middleware know if it needs to call to security plugin operations for the payload, it is not giving information about the used protection (sign or encrypt).

This information is needed by the DDS middleware to make a decision about the kind of KeyHash used (see 7.3.4 Mandatory use of the KeyHash for encrypted messages).

Add is_key_protected

This proposal will add a new EndpointSecurityAttribute: is_payload_obfuscated, so the middleware can take decisions regarding the format for the keyhash.