{
    "$schema": "http://json-schema.org/draft-04/schema#",
    "title": "Random Key Expression",
    "type": "object",
    "properties": {
        "random_key": {
            "enum": [
                "sym_key",
                "asym_prv_key"
            ]
        }
    },
    "required": [
        "random_key"
    ],
    "additionalProperties": false
}