Merge pull request ComplianceAsCode#11041 from Honny1/oval-object-model

OVAL object model

ssg/constants.py

@@ -477,3 +477,24 @@
 DEFAULT_CHRONY_CONF_PATH = '/etc/chrony.conf'
 DEFAULT_AUDISP_CONF_PATH = '/etc/audit'
 DEFAULT_SYSCTL_REMEDIATE_DROP_IN_FILE = 'false'
+
+
+# Constants for OVAL object model
+STR_TO_BOOL = {
+    "false": False,
+    "False": False,
+    "true": True,
+    "True": True,
+}
+
+BOOL_TO_STR = {True: "true", False: "false"}
+
+
+class OvalNamespaces:
+    oval = "http://oval.mitre.org/XMLSchema/oval-common-5"
+    definition = oval_namespace
+    independent = "http://oval.mitre.org/XMLSchema/oval-definitions-5#independent"
+    linux = "http://oval.mitre.org/XMLSchema/oval-definitions-5#linux"
+
+
+OVAL_NAMESPACES = OvalNamespaces()

ssg/oval_object_model/__init__.py

@@ -0,0 +1,19 @@
+from .general import (
+    ExceptionEmptyNote,
+    Notes,
+    OVALBaseObject,
+    OVALComponent,
+    OVALEntity,
+    OVALEntityProperty,
+    load_oval_entity_property,
+    load_notes,
+)
+from .oval_document import (
+    ExceptionDuplicateOVALEntity,
+    OVALDocument,
+    load_oval_document,
+)
+from .oval_entities import (
+    ExceptionDuplicateObjectReferenceInTest,
+    ExceptionMissingObjectReferenceInTest,
+)

ssg/oval_object_model/general.py

@@ -0,0 +1,181 @@
+import re
+from ..constants import BOOL_TO_STR, xsi_namespace
+from ..xml import ElementTree
+
+
+# ----- General functions
+
+
+def required_attribute(_xml_el, _key):
+    if _key in _xml_el.attrib:
+        return _xml_el.get(_key)
+    raise ValueError(
+        "%s is required but was not found in:\n%s" % (_key, repr(_xml_el.attrib))
+    )
+
+
+# ----- General Objects
+
+
+class OVALBaseObject(object):
+    __namespace = ""
+    tag = ""
+
+    def __init__(self, tag):
+        match_ns = re.match(r"\{.*\}", tag)
+        self.namespace = match_ns.group(0) if match_ns else ""
+        self.tag = tag.replace(self.namespace, "")
+
+    @property
+    def namespace(self):
+        return self.__namespace
+
+    @namespace.setter
+    def namespace(self, __value):
+        if isinstance(__value, str):
+            if not __value.startswith("{"):
+                __value = "{" + __value
+            if not __value.endswith("}"):
+                __value = __value + "}"
+        self.__namespace = __value
+
+    def __eq__(self, __value):
+        return self.__dict__ == __value.__dict__
+
+    def __repr__(self):
+        return str(self.__dict__)
+
+    def __str__(self):
+        return str(self.__dict__)
+
+    def get_xml_element(self):
+        raise NotImplementedError
+
+
+class OVALComponent(OVALBaseObject):
+    deprecated = False
+    notes = None
+    version = "0"
+
+    def __init__(self, tag, id_):
+        super(OVALComponent, self).__init__(tag)
+        self.id_ = id_
+
+    def get_xml_element(self):
+        el = ElementTree.Element("{}{}".format(self.namespace, self.tag))
+        el.set("id", self.id_)
+        el.set("version", self.version)
+        if self.deprecated:
+            el.set("deprecated", BOOL_TO_STR[self.deprecated])
+        if self.notes:
+            el.append(self.notes.get_xml_element())
+        return el
+
+
+class OVALEntity(OVALComponent):
+    comment = ""
+
+    def __init__(self, tag, id_, properties):
+        super(OVALEntity, self).__init__(tag, id_)
+        self.properties = properties
+
+    def get_xml_element(self, **attributes):
+        el = super(OVALEntity, self).get_xml_element()
+
+        for key, value in attributes.items():
+            if "xsi" in key:
+                key = ElementTree.QName(xsi_namespace, key.split(":")[-1])
+            el.set(key, value)
+
+        if self.comment:
+            el.set("comment", self.comment)
+
+        for property_ in self.properties:
+            el.append(property_.get_xml_element())
+
+        return el
+
+
+# ----- OVAL Objects
+
+
+def load_notes(oval_notes_xml_el):
+    if oval_notes_xml_el is None:
+        return None
+    notes = []
+    for note_el in oval_notes_xml_el:
+        notes.append(note_el.text)
+    return Notes(oval_notes_xml_el.tag, note_el.tag, notes)
+
+
+class ExceptionEmptyNote(Exception):
+    pass
+
+
+class Notes(OVALBaseObject):
+    def __init__(self, tag, note_tag, notes):
+        super(Notes, self).__init__(tag)
+        self.note_tag = note_tag
+        if len(notes) == 0:
+            raise ExceptionEmptyNote(
+                "Element notes should contain at least one element note."
+            )
+        self.notes = notes
+
+    def get_xml_element(self):
+        notes_el = ElementTree.Element("{}{}".format(self.namespace, self.tag))
+        for note in self.notes:
+            note_el = ElementTree.Element(self.note_tag)
+            note_el.text = note
+            notes_el.append(note_el)
+        return notes_el
+
+
+# -----
+
+
+def load_property_and_notes_of_oval_entity(oval_entity_el):
+    notes = None
+    object_property = []
+    for child_node_el in oval_entity_el:
+        if "notes" in child_node_el.tag:
+            notes = load_notes(child_node_el)
+        else:
+            object_property.append(load_oval_entity_property(child_node_el))
+    return object_property, notes
+
+
+def load_oval_entity_property(end_point_property_el):
+    data = OVALEntityProperty(end_point_property_el.tag)
+    data.attributes = (
+        end_point_property_el.attrib if end_point_property_el.attrib else None
+    )
+    data.text = end_point_property_el.text
+    for child_end_point_property_el in end_point_property_el:
+        data.add_child_property(load_oval_entity_property(child_end_point_property_el))
+    return data
+
+
+class OVALEntityProperty(OVALBaseObject):
+    attributes = None
+    text = None
+
+    def __init__(self, tag):
+        super(OVALEntityProperty, self).__init__(tag)
+        self.properties = []
+
+    def add_child_property(self, property_):
+        self.properties.append(property_)
+
+    def get_xml_element(self):
+        property_el = ElementTree.Element("{}{}".format(self.namespace, self.tag))
+        for key, val in self.attributes.items() if self.attributes is not None else {}:
+            property_el.set(key, val)
+
+        if self.text is not None:
+            property_el.text = self.text
+
+        for child in self.properties:
+            property_el.append(child.get_xml_element())
+
+        return property_el