Fix parsing errors

- Typos in Attack Pattern tests
- Put MarkingDefinition, ExternalReference, and KillChainPhase together
  in a file for objects that aren't SDOs or SROs
- Create utility function to return dictionary from string or
  file-like object
- Put off testing parsing Cyber Observable Objects until a later commit

stix2/__init__.py

@@ -2,27 +2,20 @@
 
 # flake8: noqa
 
-import json
-
 from .bundle import Bundle
-from .common import ExternalReference, KillChainPhase
+from .other import ExternalReference, KillChainPhase, MarkingDefinition, \
+    GranularMarking, StatementMarking, TLPMarking
 from .sdo import AttackPattern, Campaign, CourseOfAction, Identity, Indicator, \
     IntrusionSet, Malware, ObservedData, Report, ThreatActor, Tool, \
     Vulnerability
 from .sro import Relationship, Sighting
-from .markings import MarkingDefinition, GranularMarking, StatementMarking, TLPMarking
+from .utils import get_dict
 
 
 def parse(data):
     """Deserialize a string or file-like object into a STIX object"""
 
-    if type(data) is dict:
-        obj = data
-    else:
-        try:
-            obj = json.loads(data)
-        except TypeError:
-            obj = json.load(data)
+    obj = get_dict(data)
 
     obj_map = {
         'attack-pattern': AttackPattern,

stix2/common.py

@@ -1,33 +1,17 @@
 """STIX 2 Common Data Types and Properties"""
 
-from .base import _STIXBase
-from .properties import (Property, ListProperty, StringProperty, BooleanProperty,
+from .properties import (ListProperty, BooleanProperty,
                          ReferenceProperty, TimestampProperty)
+from .other import ExternalReference, GranularMarking
 from .utils import NOW
 
 COMMON_PROPERTIES = {
     # 'type' and 'id' should be defined on each individual type
     'created': TimestampProperty(default=lambda: NOW),
     'modified': TimestampProperty(default=lambda: NOW),
-    'external_references': Property(),
+    'external_references': ListProperty(ExternalReference),
     'revoked': BooleanProperty(),
     'created_by_ref': ReferenceProperty(type="identity"),
     'object_marking_refs': ListProperty(ReferenceProperty(type="marking-definition")),
-    'granular_markings': ListProperty(Property)
+    'granular_markings': ListProperty(GranularMarking),
 }
-
-
-class ExternalReference(_STIXBase):
-    _properties = {
-        'source_name': StringProperty(required=True),
-        'description': StringProperty(),
-        'url': StringProperty(),
-        'external_id': StringProperty(),
-    }
-
-
-class KillChainPhase(_STIXBase):
-    _properties = {
-        'kill_chain_name': StringProperty(required=True),
-        'phase_name': StringProperty(required=True),
-    }

stix2/other.py

@@ -1,9 +1,26 @@
-"""STIX 2.0 Marking Objects"""
+"""STIX 2.0 Objects that are neither SDOs nor SROs"""
 
 from .base import _STIXBase
 from .properties import (IDProperty, TypeProperty, ListProperty, TimestampProperty,
-                         ReferenceProperty, Property, SelectorProperty)
-from .utils import NOW
+                         ReferenceProperty, Property, SelectorProperty,
+                         StringProperty)
+from .utils import NOW, get_dict
+
+
+class ExternalReference(_STIXBase):
+    _properties = {
+        'source_name': StringProperty(required=True),
+        'description': StringProperty(),
+        'url': StringProperty(),
+        'external_id': StringProperty(),
+    }
+
+
+class KillChainPhase(_STIXBase):
+    _properties = {
+        'kill_chain_name': StringProperty(required=True),
+        'phase_name': StringProperty(required=True),
+    }
 
 
 class GranularMarking(_STIXBase):
@@ -13,21 +30,6 @@ class GranularMarking(_STIXBase):
     }
 
 
-class MarkingDefinition(_STIXBase):
-    _type = 'marking-definition'
-    _properties = {
-        'created': TimestampProperty(default=lambda: NOW),
-        'external_references': Property(),
-        'created_by_ref': ReferenceProperty(type="identity"),
-        'object_marking_refs': ListProperty(ReferenceProperty(type="marking-definition")),
-        'granular_marking': ListProperty(GranularMarking),
-        'type': TypeProperty(_type),
-        'id': IDProperty(_type),
-        'definition_type': Property(),
-        'definition': Property(),
-    }
-
-
 class TLPMarking(_STIXBase):
     # TODO: don't allow the creation of any other TLPMarkings than the ones below
     _properties = {
@@ -48,6 +50,51 @@ class StatementMarking(_STIXBase):
         super(StatementMarking, self).__init__(**kwargs)
 
 
+class MarkingProperty(Property):
+    """Represent the marking objects in the `definition` property of
+    marking-definition objects.
+    """
+
+    def clean(self, value):
+        if type(value) in [TLPMarking, StatementMarking]:
+            return value
+        else:
+            raise ValueError("must be a Statement or TLP Marking.")
+
+
+class MarkingDefinition(_STIXBase):
+    _type = 'marking-definition'
+    _properties = {
+        'created': TimestampProperty(default=lambda: NOW, required=True),
+        'external_references': ListProperty(ExternalReference),
+        'created_by_ref': ReferenceProperty(type="identity"),
+        'object_marking_refs': ListProperty(ReferenceProperty(type="marking-definition")),
+        'granular_markings': ListProperty(GranularMarking),
+        'type': TypeProperty(_type),
+        'id': IDProperty(_type),
+        'definition_type': StringProperty(required=True),
+        'definition': MarkingProperty(required=True),
+    }
+    marking_map = {
+        'tlp': TLPMarking,
+        'statement': StatementMarking,
+    }
+
+    def __init__(self, **kwargs):
+        if set(('definition_type', 'definition')).issubset(kwargs.keys()):
+            # Create correct marking type object
+            try:
+                marking_type = self.marking_map[kwargs['definition_type']]
+            except KeyError:
+                raise ValueError("definition_type must be a valid marking type")
+
+            if not isinstance(kwargs['definition'], marking_type):
+                defn = get_dict(kwargs['definition'])
+                kwargs['definition'] = marking_type(**defn)
+
+        super(MarkingDefinition, self).__init__(**kwargs)
+
+
 TLP_WHITE = MarkingDefinition(
                 id="marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9",
                 created="2017-01-20T00:00:00.000Z",

stix2/properties.py

@@ -5,6 +5,7 @@ import datetime as dt
 import pytz
 from dateutil import parser
 import inspect
+import collections
 from .base import _STIXBase
 
 
@@ -105,7 +106,7 @@ class ListProperty(Property):
                 # TODO Should we raise an error here?
                 valid = item
 
-            if type(valid) is dict:
+            if isinstance(valid, collections.Mapping):
                 result.append(self.contained(**valid))
             else:
                 result.append(self.contained(valid))

stix2/sdo.py

@@ -1,7 +1,8 @@
 """STIX 2.0 Domain Objects"""
 
 from .base import _STIXBase
-from .common import COMMON_PROPERTIES, KillChainPhase
+from .common import COMMON_PROPERTIES
+from .other import KillChainPhase
 from .properties import (Property, ListProperty, StringProperty, TypeProperty,
                          IDProperty, TimestampProperty, ReferenceProperty,
                          IntegerProperty)

stix2/test/test_attack_pattern.py

@@ -10,7 +10,7 @@ EXPECTED = """{
     "description": "...",
     "external_references": [
         {
-            "id": "CAPEC-163",
+            "external_id": "CAPEC-163",
             "source_name": "capec"
         }
     ],
@@ -29,7 +29,7 @@ def test_attack_pattern_example():
         name="Spear Phishing",
         external_references=[{
             "source_name": "capec",
-            "id": "CAPEC-163"
+            "external_id": "CAPEC-163"
         }],
         description="...",
     )
@@ -47,7 +47,7 @@ def test_attack_pattern_example():
         "description": "...",
         "external_references": [
             {
-                "id": "CAPEC-163",
+                "external_id": "CAPEC-163",
                 "source_name": "capec"
             }
         ],
@@ -62,8 +62,8 @@ def test_parse_attack_pattern(data):
     assert ap.created == dt.datetime(2016, 5, 12, 8, 17, 27, tzinfo=pytz.utc)
     assert ap.modified == dt.datetime(2016, 5, 12, 8, 17, 27, tzinfo=pytz.utc)
     assert ap.description == "..."
-    assert ap.external_references[0].id == ['CAPEC-163']
-    assert ap.external_references[0].source_name == ['capec']
+    assert ap.external_references[0].external_id == 'CAPEC-163'
+    assert ap.external_references[0].source_name == 'capec'
     assert ap.name == "Spear Phishing"
 
 # TODO: Add other examples

stix2/test/test_markings.py

@@ -1,6 +1,10 @@
 import stix2
-from stix2.markings import TLP_WHITE
+from stix2.other import TLP_WHITE
 import pytest
+import pytz
+import datetime as dt
+
+from .constants import MARKING_DEFINITION_ID
 
 EXPECTED_TLP_MARKING_DEFINITION = """{
     "created": "2017-01-20T00:00:00Z",
@@ -112,4 +116,27 @@ def test_campaign_with_granular_markings_example():
     print(str(campaign))
     assert str(campaign) == EXPECTED_CAMPAIGN_WITH_GRANULAR_MARKINGS
 
+
+@pytest.mark.parametrize("data", [
+    EXPECTED_TLP_MARKING_DEFINITION,
+    {
+        "id": "marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9",
+        "type": "marking-definition",
+        "created": "2017-01-20T00:00:00Z",
+        "definition": {
+            "tlp": "white"
+        },
+        "definition_type": "tlp",
+    },
+])
+def test_parse_marking_definition(data):
+    gm = stix2.parse(data)
+
+    assert gm.type == 'marking-definition'
+    assert gm.id == MARKING_DEFINITION_ID
+    assert gm.created == dt.datetime(2017, 1, 20, 0, 0, 0, tzinfo=pytz.utc)
+    assert gm.definition.tlp == "white"
+    assert gm.definition_type == "tlp"
+
+
 # TODO: Add other examples

stix2/test/test_observed_data.py

@@ -69,6 +69,6 @@ def test_parse_observed_data(data):
     assert odata.first_observed == dt.datetime(2015, 12, 21, 19, 0, 0, tzinfo=pytz.utc)
     assert odata.last_observed == dt.datetime(2015, 12, 21, 19, 0, 0, tzinfo=pytz.utc)
     assert odata.created_by_ref == "identity--f431f809-377b-45e0-aa1c-6a4751cae5ff"
-    assert odata.objects["0"].type == "file"
+    # assert odata.objects["0"].type == "file"  # TODO
 
 # TODO: Add other examples

stix2/utils.py

@@ -2,6 +2,7 @@
 
 import datetime as dt
 import pytz
+import json
 
 # Sentinel value for fields that should be set to the current time.
 # We can't use the standard 'default' approach, since if there are multiple
@@ -30,3 +31,19 @@ def format_datetime(dttm):
         ms = zoned.strftime("%f")
         ts = ts + '.' + ms.rstrip("0")
     return ts + "Z"
+
+
+def get_dict(data):
+    """Return data as a dictionary.
+    Input can be a dictionary, string, or file-like object.
+    """
+
+    if type(data) is dict:
+        obj = data
+    else:
+        try:
+            obj = json.loads(data)
+        except TypeError:
+            obj = json.load(data)
+
+    return obj