Security Automation and Continuous Monitoring M. Cokus
Internet-Draft D. Haynes
Intended status: Informational D. Rothenberg
Expires: September 8, 2016 The MITRE Corporation
J. Gonzalez
Department of Homeland Security
March 7, 2016
OVAL(R) Definitions Model
draft-haynes-sacm-oval-definitions-model-00
Abstract
This document specifies Version 5.11.1 of the OVAL Definitions Model
which defines an extensible framework for making assertions about a
system that are based upon a collection of logical statements. Each
logical statement defines a specific machine state by identifying the
data set on the system to examine and describing the expected state
of that system data.
Status of This Memo
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This Internet-Draft will expire on September 8, 2016.
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document authors. All rights reserved.
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to this document. Code Components extracted from this document must
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
2. oval_definitions . . . . . . . . . . . . . . . . . . . . . . 4
3. DefinitionsType . . . . . . . . . . . . . . . . . . . . . . . 5
4. DefinitionType . . . . . . . . . . . . . . . . . . . . . . . 6
5. MetadataType . . . . . . . . . . . . . . . . . . . . . . . . 7
6. AffectedType . . . . . . . . . . . . . . . . . . . . . . . . 8
7. ReferenceType . . . . . . . . . . . . . . . . . . . . . . . . 9
8. NotesType . . . . . . . . . . . . . . . . . . . . . . . . . . 9
9. CriteriaType . . . . . . . . . . . . . . . . . . . . . . . . 10
10. CriterionType . . . . . . . . . . . . . . . . . . . . . . . . 12
11. ExtendDefinitionType . . . . . . . . . . . . . . . . . . . . 13
12. TestsType . . . . . . . . . . . . . . . . . . . . . . . . . . 14
13. TestType . . . . . . . . . . . . . . . . . . . . . . . . . . 15
14. ObjectRefType . . . . . . . . . . . . . . . . . . . . . . . . 17
15. StateRefType . . . . . . . . . . . . . . . . . . . . . . . . 17
16. ObjectsType . . . . . . . . . . . . . . . . . . . . . . . . . 17
17. ObjectType . . . . . . . . . . . . . . . . . . . . . . . . . 17
18. set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
19. filter . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
20. StatesType . . . . . . . . . . . . . . . . . . . . . . . . . 21
21. StateType . . . . . . . . . . . . . . . . . . . . . . . . . . 21
22. VariablesType . . . . . . . . . . . . . . . . . . . . . . . . 23
23. VariableType . . . . . . . . . . . . . . . . . . . . . . . . 23
24. external_variable . . . . . . . . . . . . . . . . . . . . . . 25
25. PossibleValueType . . . . . . . . . . . . . . . . . . . . . . 25
26. PossibleRestrictionType . . . . . . . . . . . . . . . . . . . 26
27. RestrictionType . . . . . . . . . . . . . . . . . . . . . . . 26
28. constant_variable . . . . . . . . . . . . . . . . . . . . . . 27
29. ValueType . . . . . . . . . . . . . . . . . . . . . . . . . . 27
30. local_variable . . . . . . . . . . . . . . . . . . . . . . . 27
31. ComponentGroup . . . . . . . . . . . . . . . . . . . . . . . 28
32. LiteralComponentType . . . . . . . . . . . . . . . . . . . . 29
33. ObjectComponentType . . . . . . . . . . . . . . . . . . . . . 30
34. VariableComponentType . . . . . . . . . . . . . . . . . . . . 31
35. FunctionGroup . . . . . . . . . . . . . . . . . . . . . . . . 32
36. ArithmeticFunctionType . . . . . . . . . . . . . . . . . . . 34
37. BeginFunctionType . . . . . . . . . . . . . . . . . . . . . . 35
38. ConcatFunctionType . . . . . . . . . . . . . . . . . . . . . 35
39. CountFunctionType . . . . . . . . . . . . . . . . . . . . . . 36
40. EndFunctionType . . . . . . . . . . . . . . . . . . . . . . . 36
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41. EscapeRegexFunctionType . . . . . . . . . . . . . . . . . . . 37
42. SplitFunctionType . . . . . . . . . . . . . . . . . . . . . . 37
43. SubstringFunctionType . . . . . . . . . . . . . . . . . . . . 38
44. TimeDifferenceFunctionType . . . . . . . . . . . . . . . . . 40
45. UniqueFunctionType . . . . . . . . . . . . . . . . . . . . . 41
46. RegexCaptureFunctionType . . . . . . . . . . . . . . . . . . 41
47. ArithmeticEnumeration . . . . . . . . . . . . . . . . . . . . 42
48. DateTimeFormatEnumeration . . . . . . . . . . . . . . . . . . 43
49. FilterActionEnumeration . . . . . . . . . . . . . . . . . . . 45
50. SetOperatorEnumeration . . . . . . . . . . . . . . . . . . . 45
51. EntityAttributeGroup . . . . . . . . . . . . . . . . . . . . 45
52. EntitySimpleBaseType . . . . . . . . . . . . . . . . . . . . 47
53. EntityComplexBaseType . . . . . . . . . . . . . . . . . . . . 47
54. EntityObjectIPAddressType . . . . . . . . . . . . . . . . . . 47
55. EntityObjectIPAddressStringType . . . . . . . . . . . . . . . 48
56. EntityObjectAnySimpleType . . . . . . . . . . . . . . . . . . 48
57. EntityObjectBinaryType . . . . . . . . . . . . . . . . . . . 49
58. EntityObjectBoolType . . . . . . . . . . . . . . . . . . . . 49
59. EntityObjectFloatType . . . . . . . . . . . . . . . . . . . . 50
60. EntityObjectIntType . . . . . . . . . . . . . . . . . . . . . 50
61. EntityObjectStringType . . . . . . . . . . . . . . . . . . . 50
62. EntityObjectVersionType . . . . . . . . . . . . . . . . . . . 51
63. EntityObjectRecordType . . . . . . . . . . . . . . . . . . . 51
64. EntityObjectFieldType . . . . . . . . . . . . . . . . . . . . 53
65. EntityStateSimpleBaseType . . . . . . . . . . . . . . . . . . 53
66. EntityStateComplexBaseType . . . . . . . . . . . . . . . . . 54
67. EntityStateIPAddressType . . . . . . . . . . . . . . . . . . 54
68. EntityStateIPAddressStringType . . . . . . . . . . . . . . . 55
69. EntityStateAnySimpleType . . . . . . . . . . . . . . . . . . 55
70. EntityStateBinaryType . . . . . . . . . . . . . . . . . . . . 56
71. EntityStateBoolType . . . . . . . . . . . . . . . . . . . . . 56
72. EntityStateFloatType . . . . . . . . . . . . . . . . . . . . 57
73. EntityStateIntType . . . . . . . . . . . . . . . . . . . . . 57
74. EntityStateEVRStringType . . . . . . . . . . . . . . . . . . 57
75. EntityStateDebianEVRStringType . . . . . . . . . . . . . . . 58
76. EntityStateVersionType . . . . . . . . . . . . . . . . . . . 58
77. EntityStateFileSetRevisionType . . . . . . . . . . . . . . . 59
78. EntityStateIOSVersionType . . . . . . . . . . . . . . . . . . 59
79. EntityStateStringType . . . . . . . . . . . . . . . . . . . . 60
80. EntityStateRecordType . . . . . . . . . . . . . . . . . . . . 60
81. EntityStateFieldType . . . . . . . . . . . . . . . . . . . . 62
82. OVAL Definitions Model Schema . . . . . . . . . . . . . . . . 62
83. Intellectual Property Considerations . . . . . . . . . . . . 167
84. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 167
85. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 167
86. Security Considerations . . . . . . . . . . . . . . . . . . . 167
87. References . . . . . . . . . . . . . . . . . . . . . . . . . 168
87.1. Normative References . . . . . . . . . . . . . . . . . . 168
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87.2. Informative References . . . . . . . . . . . . . . . . . 168
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 168
1. Introduction
The Open Vulnerability and Assessment Language (OVAL) [OVAL-WEBSITE]
is an international, information security community effort to
standardize how to assess and report upon the machine state of
systems. For over ten years, OVAL has been developed in
collaboration with any and all interested parties to promote open and
publicly available security content and to standardize the
representation of this information across the entire spectrum of
security tools and services.
OVAL provides an established framework for making assertions about a
system's state by standardizing the three main steps of the
assessment process: representing the current machine state; analyzing
the system for the presence of the specified machine state; and
representing the results of the assessment which facilitates
collaboration and information sharing among the information security
community and interoperability among tools.
This draft is part of the OVAL contribution to the IETF SACM WG that
standardizes the representation used to analyze a system for the
presence of a specific machine state. It is intended to serve as a
starting point for the endpoint posture assessment data modeling
needs of SACM specifically Collection Guidance and Evaluation
Guidance.
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
2. oval_definitions
The oval_definitions type defines the base structure in the OVAL
Definitions Model for representing a collection of OVAL Definitions.
This container type adds metadata about the origin of the content and
allows for a signature.
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+-------------+--------------------+-------+------------------------+
| Property | Type | Count | Description |
+-------------+--------------------+-------+------------------------+
| generator | oval:GeneratorType | 1 | Provides information |
| | | | regarding the origin |
| | | | of the OVAL Content. |
| | | | The timestamp property |
| | | | of the generator MUST |
| | | | represent the time at |
| | | | which the |
| | | | oval_definitions was |
| | | | created. |
| | | | |
| definitions | DefinitionsType | 0..1 | Container for OVAL |
| | | | Definitions. |
| | | | |
| tests | TestsType | 0..1 | Container for OVAL |
| | | | Tests. |
| | | | |
| objects | ObjectsType | 0..1 | Container for OVAL |
| | | | Objects. |
| | | | |
| states | StatesType | 0..1 | Container for OVAL |
| | | | Tests. |
| | | | |
| variables | VariablesType | 0..1 | Container for OVAL |
| | | | Variables. |
| | | | |
| signature | ext:Signature | 0..1 | Mechanism to ensure |
| | | | the integrity and |
| | | | authenticity of the |
| | | | content. |
+-------------+--------------------+-------+------------------------+
Table 1: oval_definitions Construct
3. DefinitionsType
The DefinitionsType provides a container for one or more OVAL
Definitions.
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+------------+----------------+-------+-----------------------------+
| Property | Type | Count | Description |
+------------+----------------+-------+-----------------------------+
| definition | DefinitionType | 1..* | One or more OVAL |
| | | | Definitions. |
+------------+----------------+-------+-----------------------------+
Table 2: DefinitionsType Construct
4. DefinitionType
The DefinitionType defines a single OVAL Definition. An OVAL
Definition is the key structure in the OVAL Definition Model. It is
a collection of logical statements that combine to make an overall
assertion about a system state and metadata about the assertion.
+------------+--------------------------+-------+-------------------+
| Property | Type | Count | Description |
+------------+--------------------------+-------+-------------------+
| id | oval:DefinitionIDPattern | 1 | The globally |
| | | | unique identifier |
| | | | of the OVAL |
| | | | Definition. |
| | | | |
| version | unsigned integer | 1 | The version of |
| | | | the OVAL |
| | | | Definition. |
| | | | |
| class | oval:ClassEnumeration | 1 | The class of the |
| | | | OVAL Definition. |
| | | | |
| deprecated | boolean | 0..1 | Whether or not |
| | | | the OVAL |
| | | | Definition has |
| | | | been deprecated. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| metadata | MetadataType | 1 | Container for |
| | | | metadata |
| | | | associated with |
| | | | the OVAL |
| | | | Definition. |
| | | | Metadata is |
| | | | informational |
| | | | only and does not |
| | | | impact the |
| | | | evaluation of the |
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| | | | OVAL Definition. |
| | | | |
| notes | NotesType | 0..1 | A container for |
| | | | individual notes |
| | | | that describe |
| | | | some aspect of |
| | | | the OVAL |
| | | | Definition. |
| | | | |
| criteria | CriteriaType | 0..1 | A container for |
| | | | the logical |
| | | | criteria that is |
| | | | defined by the |
| | | | OVAL Definition. |
| | | | All non- |
| | | | deprecated OVAL |
| | | | Definitions MUST |
| | | | contain at least |
| | | | one criteria to |
| | | | express the |
| | | | logical assertion |
| | | | being made by the |
| | | | OVAL Definition. |
| | | | |
| signature | ext:Signature | 0..1 | Mechanism to |
| | | | ensure the |
| | | | integrity and |
| | | | authenticity of |
| | | | the content. |
+------------+--------------------------+-------+-------------------+
Table 3: DefinitionType Construct
5. MetadataType
The MetadataType is a container for additional metadata that
describes an OVAL Definition.
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+-----------------+---------------+-------+-------------------------+
| Property | Type | Count | Description |
+-----------------+---------------+-------+-------------------------+
| title | string | 1 | A short text title for |
| | | | the OVAL Definition. |
| | | | |
| affected | AffectedType | 0..* | A container for the |
| | | | list of affected |
| | | | platforms by a given |
| | | | OVAL Definition. |
| | | | |
| reference | ReferenceType | 0..* | References allow |
| | | | pointers to external |
| | | | information about an |
| | | | OVAL Definition. |
| | | | |
| description | string | 1 | A detailed text |
| | | | description of the OVAL |
| | | | Definition. |
| | | | |
| extension_point | Any | 0..* | An extension point that |
| | | | allows for the |
| | | | inclusion of any |
| | | | additional metadata |
| | | | associated with the |
| | | | OVAL Definition. |
+-----------------+---------------+-------+-------------------------+
Table 4: MetadataType Construct
The extension_point property is not considered a part of the OVAL
Language proper, but rather, an extension point that allows
organizations to expand the OVAL Language to better suit their needs.
6. AffectedType
The AffectedType is a container type for the list of affected
platforms and products. Note that the absence of a platform or
product implies that the OVAL Definition applies to all platforms or
products.
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+----------+------------------------+-------+-----------------------+
| Property | Type | Count | Description |
+----------+------------------------+-------+-----------------------+
| family | oval:FamilyEnumeration | 1 | The high-level |
| | | | classification of the |
| | | | system type. |
| | | | |
| platform | string | 0..* | The name identifying |
| | | | a specific software |
| | | | platform. Convention |
| | | | is not to spell out |
| | | | the names. |
| | | | |
| product | string | 0..* | The name identifying |
| | | | a specific software |
| | | | product. Convention |
| | | | is to spell out the |
| | | | names. |
+----------+------------------------+-------+-----------------------+
Table 5: AffectedType Construct
7. ReferenceType
The ReferenceType is a pointer to an external reference that supports
or adds more information to an OVAL Definition.
+----------+--------+-------+-----------------------------------+
| Property | Type | Count | Description |
+----------+--------+-------+-----------------------------------+
| source | string | 1 | The source of the reference. |
| | | | |
| ref_id | string | 1 | The identifier for the reference. |
| | | | |
| ref_url | URI | 0..1 | The URL for the reference. |
+----------+--------+-------+-----------------------------------+
Table 6: ReferenceType Construct
8. NotesType
The NotesType is a container for one or more notes, providing
additional information, such as unresolved questions, reasons for
specific implementation, or other documentation.
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+----------+--------+-------+-------------------------+
| Property | Type | Count | Description |
+----------+--------+-------+-------------------------+
| note | string | 1..* | One or more text notes. |
+----------+--------+-------+-------------------------+
Table 7: NotesType Construct
9. CriteriaType
The CriteriaType defines the structure of a logical statement that
combines other logical statements. This construct is used to combine
references to OVAL Tests, OVAL Definitions, and other CriteriaTypes
into one logical statement.
+------------------+----------------------+-------+-----------------+
| Property | Type | Count | Description |
+------------------+----------------------+-------+-----------------+
| operator | oval:OperatorEnumera | 0..1 | The logical |
| | tion | | operator that |
| | | | is used to |
| | | | combine the |
| | | | individual |
| | | | results of the |
| | | | logical |
| | | | statements |
| | | | defined by the |
| | | | criteria, |
| | | | criterion, and |
| | | | extend_definiti |
| | | | on properties. |
| | | | Default Value: |
| | | | 'AND'. |
| | | | |
| negate | boolean | 0..1 | Specifies |
| | | | whether or not |
| | | | the evaluation |
| | | | result of the |
| | | | CriteriaType |
| | | | should be |
| | | | negated. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| comment | oval:NonEmptyStringT | 0..1 | A short |
| | ype | | description of |
| | | | the criteria. |
| | | | |
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| criteria | CriteriaType | 0..* | A collection of |
| | | | logical |
| | | | statements that |
| | | | will be |
| | | | combined |
| | | | according to |
| | | | the operator |
| | | | property. At |
| | | | least one |
| | | | criteria, |
| | | | criterion, or e |
| | | | xtend_definitio |
| | | | n MUST be |
| | | | present. |
| | | | |
| criterion | CriterionType | 0..* | A logical |
| | | | statement that |
| | | | references an |
| | | | OVAL Test and |
| | | | will be |
| | | | combined |
| | | | according to |
| | | | the operator |
| | | | property. At |
| | | | least one |
| | | | criteria, |
| | | | criterion, or e |
| | | | xtend_definitio |
| | | | n MUST be |
| | | | present. |
| | | | |
| extend_definitio | ExtendDefinitionType | 0..* | A logical |
| n | | | statement that |
| | | | references an |
| | | | OVAL Definition |
| | | | and will be |
| | | | combined |
| | | | according to |
| | | | the operator |
| | | | property. At |
| | | | least one |
| | | | criteria, |
| | | | criterion, or e |
| | | | xtend_definitio |
| | | | n MUST be |
| | | | present. |
| | | | |
| applicability_ch | boolean | 0..1 | A boolean flag |
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| eck | | | that when |
| | | | 'true' |
| | | | indicates that |
| | | | the criteria is |
| | | | being used to |
| | | | determine |
| | | | whether the |
| | | | OVAL Definition |
| | | | applies to a |
| | | | given system. |
| | | | No additional |
| | | | meaning is |
| | | | assumed when |
| | | | 'false'. |
+------------------+----------------------+-------+-----------------+
Table 8: CriteriaType Construct
10. CriterionType
The CriterionType is a logical statement that references an OVAL
Test.
+--------------------+-----------------------+-------+--------------+
| Property | Type | Count | Description |
+--------------------+-----------------------+-------+--------------+
| test_ref | oval:TestIDPattern | 1 | The globally |
| | | | unique |
| | | | identifier |
| | | | of an OVAL |
| | | | Test |
| | | | contained in |
| | | | the OVAL |
| | | | Definitions. |
| | | | |
| negate | boolean | 0..1 | Specifies |
| | | | whether or |
| | | | not the |
| | | | evaluation |
| | | | result of |
| | | | the OVAL |
| | | | Test, |
| | | | referenced |
| | | | by the |
| | | | test_ref |
| | | | property, |
| | | | should be |
| | | | negated. |
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| | | | Default |
| | | | Value: |
| | | | 'false'. |
| | | | |
| comment | oval:NonEmptyStringTy | 0..1 | A short |
| | pe | | description |
| | | | of the |
| | | | criterion. |
| | | | |
| applicability_chec | boolean | 0..1 | A boolean |
| k | | | flag that |
| | | | when 'true' |
| | | | indicates |
| | | | that the |
| | | | criterion is |
| | | | being used |
| | | | to determine |
| | | | whether the |
| | | | OVAL |
| | | | Definition |
| | | | applies to a |
| | | | given |
| | | | system. No |
| | | | additional |
| | | | meaning is |
| | | | assumed when |
| | | | 'false'. |
+--------------------+-----------------------+-------+--------------+
Table 9: CriterionType Construct
11. ExtendDefinitionType
The ExtendDefinitionType is a logical statement that references
another OVAL Definition.
+------------------+-----------------------+-------+----------------+
| Property | Type | Count | Description |
+------------------+-----------------------+-------+----------------+
| definition_ref | oval:DefinitionIDPatt | 1 | The globally |
| | ern | | unique |
| | | | identifier of |
| | | | an OVAL |
| | | | Definition |
| | | | contained in |
| | | | the OVAL |
| | | | Definitions. |
| | | | |
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| negate | boolean | 0..1 | Specifies |
| | | | whether or not |
| | | | the evaluation |
| | | | result of the |
| | | | OVAL |
| | | | Definition, |
| | | | referenced by |
| | | | the |
| | | | definition_ref |
| | | | property, |
| | | | should be |
| | | | negated. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| comment | oval:NonEmptyStringTy | 0..1 | A short |
| | pe | | description of |
| | | | the extended |
| | | | OVAL |
| | | | Definition. |
| | | | |
| applicability_ch | boolean | 0..1 | A boolean flag |
| eck | | | that when |
| | | | 'true' |
| | | | indicates that |
| | | | the ExtendDefi |
| | | | nition is |
| | | | being used to |
| | | | determine |
| | | | whether the |
| | | | OVAL |
| | | | Definition |
| | | | applies to a |
| | | | given system. |
| | | | No additional |
| | | | meaning is |
| | | | assumed when |
| | | | 'false'. |
+------------------+-----------------------+-------+----------------+
Table 10: ExtendDefinitionType Construct
12. TestsType
The TestsType provides a container for one or more OVAL Tests.
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+----------+----------+-------+-------------------------+
| Property | Type | Count | Description |
+----------+----------+-------+-------------------------+
| test | TestType | 1..* | One or more OVAL Tests. |
+----------+----------+-------+-------------------------+
Table 11: TestsType Construct
13. TestType
The TestType is an abstract OVAL Test that defines the common
properties associated with all OVAL Tests. The TestType provides an
extension point for concrete OVAL Tests, which define platform-
specific capabilities in OVAL Component Models. An OVAL Test defines
the relationship between an OVAL Object and zero or more OVAL States,
specifying exactly how many OVAL Items must exist on the system and
how many of those OVAL Items must satisfy the set of referenced OVAL
States.
+--------------+----------------------+-------+---------------------+
| Property | Type | Count | Description |
+--------------+----------------------+-------+---------------------+
| id | oval:TestIDPattern | 1 | The globally unique |
| | | | identifier of an |
| | | | OVAL Test. |
| | | | |
| version | unsigned int | 1 | The version of the |
| | | | unique OVAL Test. |
| | | | |
| check_existe | oval:ExistenceEnumer | 0..1 | Specifies how many |
| nce | ation | | OVAL Items must |
| | | | exist, on the |
| | | | system, in order |
| | | | for the OVAL Test |
| | | | to evaluate to |
| | | | 'true'. Default |
| | | | Value: 'at_least_on |
| | | | e_exists'. |
| | | | |
| check | oval:CheckEnumeratio | 1 | Specifies how many |
| | n | | of the collected |
| | | | OVAL Items must |
| | | | satisfy the |
| | | | requirements |
| | | | specified by the |
| | | | OVAL State(s) in |
| | | | order for the OVAL |
| | | | Test to evaluate to |
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| | | | 'true'. |
| | | | |
| state_operat | oval:OperatorEnumera | 0..1 | Specifies how to |
| or | tion | | logically combine |
| | | | the OVAL States |
| | | | referenced in the |
| | | | OVAL Test. Default |
| | | | Value: 'AND'. |
| | | | |
| comment | oval:NonEmptyStringT | 1 | A short description |
| | ype | | of the OVAL Test. |
| | | | This value SHOULD |
| | | | describe the intent |
| | | | of the OVAL Test |
| | | | including the |
| | | | system information |
| | | | that is examined |
| | | | and the expected |
| | | | state of that |
| | | | information. |
| | | | |
| deprecated | boolean | 0..1 | Whether or not the |
| | | | OVAL Test has been |
| | | | deprecated. A |
| | | | deprecated OVAL |
| | | | Test is one that |
| | | | should no longer be |
| | | | referenced by new |
| | | | OVAL Content. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| notes | NotesType | 0..1 | A container for |
| | | | individual notes |
| | | | that describe some |
| | | | aspect of the OVAL |
| | | | Test. |
| | | | |
| signature | ext:Signature | 0..1 | Mechanism to ensure |
| | | | the integrity and |
| | | | authenticity of the |
| | | | content. |
+--------------+----------------------+-------+---------------------+
Table 12: TestType Construct
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14. ObjectRefType
The ObjectRefType provides to an existing OVAL Object.
+------------+----------------------+-------+-----------------------+
| Property | Type | Count | Description |
+------------+----------------------+-------+-----------------------+
| object_ref | oval:ObjectIDPattern | 1 | A reference to an |
| | | | existing OVAL Object. |
+------------+----------------------+-------+-----------------------+
Table 13: ObjectRefType Construct
15. StateRefType
The StateRefType provides to an existing OVAL State.
+-----------+---------------------+-------+-------------------------+
| Property | Type | Count | Description |
+-----------+---------------------+-------+-------------------------+
| state_ref | oval:StateIDPattern | 1 | A reference to an |
| | | | existing OVAL State. |
+-----------+---------------------+-------+-------------------------+
Table 14: StateRefType Construct
16. ObjectsType
The ObjectsType provides a container for one or more OVAL Objects.
+----------+------------+-------+-------------------------------+
| Property | Type | Count | Description |
+----------+------------+-------+-------------------------------+
| object | ObjectType | 1..* | A collection of OVAL Objects. |
+----------+------------+-------+-------------------------------+
Table 15: ObjectsType Construct
17. ObjectType
The ObjectType is an abstract OVAL Object that defines the common
properties associated with all OVAL Objects. The ObjectType provides
an extension point for normal or "concrete" OVAL Objects, which
define platform-specific capabilities, in the OVAL Component Models.
A concrete OVAL Object MUST define sufficient entities to allow a
user to identify a unique an item to be collected.
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A concrete OVAL Object may define a set of 0 or more OVAL Behaviors.
OVAL Behaviors define an action that can further specify the set of
OVAL Items that match an OVAL Object. OVAL Behaviors may depend on
other OVAL Behaviors or may be independent of other OVAL Behaviors.
In addition, OVAL Behaviors are specific to OVAL Objects and are
defined in the OVAL Component Models.
+------------+-------------------------+-------+--------------------+
| Property | Type | Count | Description |
+------------+-------------------------+-------+--------------------+
| id | oval:ObjectIDPattern | 1 | The globally |
| | | | unique identifier |
| | | | of an OVAL Object |
| | | | contained in the |
| | | | OVAL Definitions. |
| | | | |
| version | unsigned int | 1 | The version of the |
| | | | globally unique |
| | | | OVAL Object |
| | | | referenced by the |
| | | | id property. |
| | | | |
| comment | oval:NonEmptyStringType | 1 | A short |
| | | | description of the |
| | | | OVAL Object. |
| | | | |
| deprecated | boolean | 0..1 | Whether or not the |
| | | | OVAL Object has |
| | | | been deprecated. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| notes | NotesType | 0..1 | A container for |
| | | | individual notes |
| | | | that describe some |
| | | | aspect of the OVAL |
| | | | Object. |
| | | | |
| signature | ext:Signature | 0..1 | Mechanism to |
| | | | ensure the |
| | | | integrity and |
| | | | authenticity of |
| | | | the content. |
+------------+-------------------------+-------+--------------------+
Table 16: ObjectType Construct
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18. set
The set construct enables the expression of complex OVAL Objects that
are the result of logically combining and filtering the OVAL Items
that are identified by one or more other OVAL Objects. A set can
consist of either one or two nested sets or one or two references to
other OVAL Objects and a collection of OVAL Filters.
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+-----------------+----------------------+-------+------------------+
| Property | Type | Count | Description |
+-----------------+----------------------+-------+------------------+
| set_operator | SetOperatorEnumerati | 0..1 | Specifies the |
| | on | | set operation to |
| | | | use when |
| | | | combining |
| | | | subsets. Default |
| | | | Value: 'UNION'. |
| | | | |
| set | set | 0..2 | Allowed nested |
| | | | sets. |
| | | | |
| object_referenc | oval:ObjectIDPattern | 0..2 | A reference to |
| e | | | an OVAL Object |
| | | | based upon its |
| | | | ID. An |
| | | | object_reference |
| | | | indicates that |
| | | | any OVAL Items |
| | | | identified by |
| | | | the referenced |
| | | | OVAL Object are |
| | | | included in the |
| | | | set. The |
| | | | referenced OVAL |
| | | | Object MUST be |
| | | | contained within |
| | | | the current |
| | | | instance of the |
| | | | OVAL Definitions |
| | | | Model and MUST |
| | | | be of the same |
| | | | type as the OVAL |
| | | | Object that is |
| | | | referencing it. |
| | | | |
| filter | filter | 0..n | Defines one or |
| | | | more filters to |
| | | | apply to |
| | | | combined data. |
+-----------------+----------------------+-------+------------------+
Table 17: set Construct
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19. filter
The filter construct allows the explicit inclusion or exclusion of
OVAL Items from a collection of OVAL Items based upon one an OVAL
State.
+----------+-------------------------+-------+----------------------+
| Property | Type | Count | Description |
+----------+-------------------------+-------+----------------------+
| action | FilterActionEnumeration | 0..1 | Defines the type of |
| | | | filter. Default |
| | | | Value: 'exclude'. |
| | | | |
| value | oval:StateIDPattern | 1 | A reference to an |
| | | | OVAL State that |
| | | | defines how the data |
| | | | should be filtered. |
| | | | The referenced OVAL |
| | | | State MUST be |
| | | | contained within the |
| | | | current instance of |
| | | | the OVAL Definitions |
| | | | Model and MUST be of |
| | | | the same type as the |
| | | | OVAL Object that is |
| | | | referencing it. |
+----------+-------------------------+-------+----------------------+
Table 18: filter Construct
20. StatesType
The StatesType provides a container for one or more OVAL States.
+----------+-----------+-------+------------------------------+
| Property | Type | Count | Description |
+----------+-----------+-------+------------------------------+
| state | StateType | 1..* | A collection of OVAL States. |
+----------+-----------+-------+------------------------------+
Table 19: StatesType Construct
21. StateType
The StateType is an abstract OVAL State that defines the common
properties associated with all OVAL States. The StateType provides
an extension point for concrete OVAL States, which define platform-
specific capabilities in the OVAL Component Models. The StateType is
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extended by concrete OVAL States in order to define platform specific
capabilities. Each concrete OVAL State is comprised of a set of
entities that describe a specific system state.
+------------+--------------------------+-------+-------------------+
| Property | Type | Count | Description |
+------------+--------------------------+-------+-------------------+
| id | oval:StateIDPattern | 1 | The globally |
| | | | unique identifier |
| | | | of an OVAL State |
| | | | contained in the |
| | | | OVAL Definitions. |
| | | | |
| version | unsigned int | 1 | The version of |
| | | | the globally |
| | | | unique OVAL State |
| | | | referenced by the |
| | | | id property. |
| | | | |
| operator | oval:OperatorEnumeration | 0..1 | The value to be |
| | | | used as the |
| | | | operator for the |
| | | | OVAL State, in |
| | | | order to know how |
| | | | to combine the |
| | | | set of entities |
| | | | defined within |
| | | | the concrete OVAL |
| | | | State. Default |
| | | | Value: 'AND'. |
| | | | |
| comment | oval:NonEmptyStringType | 1 | A short |
| | | | description of |
| | | | the OVAL State. |
| | | | |
| deprecated | boolean | 0..1 | Whether or not |
| | | | the OVAL Object |
| | | | has been |
| | | | deprecated. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| notes | NotesType | 0..1 | A container for |
| | | | individual notes |
| | | | that describe |
| | | | some aspect of |
| | | | the OVAL State. |
| | | | |
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| signature | ext:Signature | 0..1 | Mechanism to |
| | | | ensure the |
| | | | integrity and |
| | | | authenticity of |
| | | | the content. |
+------------+--------------------------+-------+-------------------+
Table 20: ObjectType Construct
22. VariablesType
The VariablesType provides a container for one or more OVAL
Variables.
+----------+--------------+-------+------------------------------+
| Property | Type | Count | Description |
+----------+--------------+-------+------------------------------+
| variable | VariableType | 1..* | A collection of OVAL States. |
+----------+--------------+-------+------------------------------+
Table 21: VariablesType Construct
23. VariableType
The VariableType is an abstract OVAL Variable that defines the common
properties associated with all OVAL Variables defined in the OVAL
Definition Model. The VariableType provides an extension point for
concrete OVAL Variables. Concrete OVAL Variables extend this type to
provide specific details.
Each concrete OVAL Variable has a collection of values. This
collection of values may be the empty set. The proper handling of an
empty collection of values for a given variable is left to the
context in which the OVAL Variable is used. In some contexts an
empty collection of values will be an error, and in other contexts an
empty collection of values will be needed for proper evaluation.
This context sensitive behavior is defined in [I-D.draft-haynes-sacm-
oval-processing-model]. All OVAL Variable values MUST conform to the
datatype specified by the datatype property.
+-----------+-------------------------------+-------+---------------+
| Property | Type | Count | Description |
+-----------+-------------------------------+-------+---------------+
| id | oval:VariableIDPattern | 1 | The globally |
| | | | unique |
| | | | identifier of |
| | | | an OVAL |
| | | | Variable |
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| | | | contained in |
| | | | the OVAL |
| | | | Definitions. |
| | | | |
| version | unsigned int | 1 | The version |
| | | | of the |
| | | | globally |
| | | | unique OVAL |
| | | | Variable |
| | | | referenced by |
| | | | the id |
| | | | property. |
| | | | |
| datatype | oval:SimpleDatatypeEnumeratio | 1 | The datatype |
| | n | | of the |
| | | | value(s) in |
| | | | the OVAL |
| | | | Variable. The |
| | | | 'record' |
| | | | datatype is |
| | | | not supported |
| | | | in OVAL |
| | | | Variables. |
| | | | |
| comment | oval:NonEmptyStringType | 1 | The |
| | | | documentation |
| | | | associated |
| | | | with the OVAL |
| | | | Variable |
| | | | instance. |
| | | | |
| deprecate | boolean | 0..1 | Whether or |
| d | | | not the OVAL |
| | | | Variable has |
| | | | been |
| | | | deprecated. |
| | | | Default |
| | | | Value: |
| | | | 'false'. |
| | | | |
| signature | ext:Signature | 0..1 | Mechanism to |
| | | | ensure the |
| | | | integrity and |
| | | | authenticity |
| | | | of the |
| | | | content. |
+-----------+-------------------------------+-------+---------------+
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Table 22: VariableType Construct
24. external_variable
The external_variable is an extension of the VariableType and
provides a way of defining variables whose values come from a source
outside of the OVAL Definition.
An external_variable can have any number of possible_value and/or
possible_restriction elements in any order.
+--------------------+------------------------+-------+-------------+
| Property | Type | Count | Description |
+--------------------+------------------------+-------+-------------+
| possible_value | PossibleValueType | 0..* | Defines one |
| | | | acceptable |
| | | | value for |
| | | | an external |
| | | | variable. |
| | | | |
| possible_restricti | PossibleRestrictionTyp | 0..* | Defines a |
| on | e | | range of |
| | | | acceptable |
| | | | values for |
| | | | an external |
| | | | variable. |
+--------------------+------------------------+-------+-------------+
Table 23: external_variable Construct
25. PossibleValueType
The PossibleValueType provides a way to explicitly state an
acceptable value for an external variable.
+----------+--------+-------+---------------------------------------+
| Property | Type | Count | Description |
+----------+--------+-------+---------------------------------------+
| hint | string | 1 | A short description that describes |
| | | | the allowed value. |
| | | | |
| value | string | 1 | An acceptable value for the external |
| | | | variable. |
+----------+--------+-------+---------------------------------------+
Table 24: PossibleValueType Construct
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26. PossibleRestrictionType
The PossibleRestrictionType provides a way to explicitly list a range
of acceptable values for an external variable. The operation
attribute may be used to combine multiple restriction elements using
a specified operation. See the Operator Enumeration Evaluation
section in [I-D.draft-haynes-sacm-oval-processing-model] for more
information on how to combine the individual results.
+-------------+----------------------+-------+----------------------+
| Property | Type | Count | Description |
+-------------+----------------------+-------+----------------------+
| restriction | RestrictionType | 1..* | The restriction that |
| | | | is being applied. |
| | | | |
| operation | OperationEnumeration | 1 | The operation to be |
| | | | applied to the |
| | | | restriction. Default |
| | | | Value: 'AND'. |
| | | | |
| hint | string | 1 | A short description |
| | | | that describes the |
| | | | allowed value. |
+-------------+----------------------+-------+----------------------+
Table 25: PossibleRestrictionType Construct
27. RestrictionType
The RestrictionType defines how to describe a restriction for an
external variable.
+-----------+----------------------+-------+------------------------+
| Property | Type | Count | Description |
+-----------+----------------------+-------+------------------------+
| operation | OperationEnumeration | 1 | The operation to be |
| | | | applied to the |
| | | | restriction. Default |
| | | | Value: 'AND'. |
| | | | |
| value | string | 1 | An acceptable value |
| | | | for the external |
| | | | variable. |
+-----------+----------------------+-------+------------------------+
Table 26: RestrictionType Construct
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28. constant_variable
The constant_variable extends the VariableType and provides a way of
defining variables whose value is immutable.
+----------+-----------+-------+------------------------------------+
| Property | Type | Count | Description |
+----------+-----------+-------+------------------------------------+
| value | ValueType | 1..* | Defines a value represented by the |
| | | | OVAL Variable. |
+----------+-----------+-------+------------------------------------+
Table 27: constant_variable Construct
29. ValueType
The ValueType element defines a variable value.
+----------+--------+-------+---------------------------------------+
| Property | Type | Count | Description |
+----------+--------+-------+---------------------------------------+
| value | string | 0..* | Allows any simple type to be used as |
| | | | a value. If no value is specified the |
| | | | value is considered to be the empty |
| | | | string. |
+----------+--------+-------+---------------------------------------+
Table 28: ValueType Construct
30. local_variable
The local_variable is an extension of the VariableType and provides a
way of defining variables whose value is determined by another local
OVAL Construct. The value of this variable is determined at
evaluation time.
A local_variable can be constructed from a single component or via
complex functions to manipulate the referenced components.
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+------------+-----------------+-------+----------------------------+
| Property | Type | Count | Description |
+------------+-----------------+-------+----------------------------+
| components | ComponentsGroup | 1..* | The collection of |
| | | | ComponentGroup constructs |
| | | | to be evaluated in the |
| | | | local_variable. |
+------------+-----------------+-------+----------------------------+
Table 29: local_variable Construct
31. ComponentGroup
The ComponentGroup defines a set of constructs that can be used
within a local_variable or OVAL Function. When defining a
local_variable or OVAL Function, one or more of these constructs
maybe used to specify the desired collection of values for the OVAL
Variable.
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+--------------------+-----------------------+-------+--------------+
| Property | Type | Count | Description |
+--------------------+-----------------------+-------+--------------+
| object_component | ObjectComponentType | 0..* | A component |
| | | | of an OVAL |
| | | | Variable |
| | | | whose value |
| | | | comes from |
| | | | an OVAL |
| | | | Object. |
| | | | |
| variable_component | VariableComponentType | 0..* | A component |
| | | | of an OVAL |
| | | | Variable |
| | | | whose value |
| | | | comes from |
| | | | another OVAL |
| | | | Variable. |
| | | | |
| literal_component | LiteralComponentType | 0..* | A component |
| | | | of an OVAL |
| | | | Variable |
| | | | whose value |
| | | | is a literal |
| | | | value. |
| | | | |
| functions | FunctionGroup | 0..* | One or more |
| | | | of a set of |
| | | | functions |
| | | | that act |
| | | | upon one or |
| | | | more |
| | | | components |
| | | | of an OVAL |
| | | | Variable. |
+--------------------+-----------------------+-------+--------------+
Table 30: ComponentGroup Construct
32. LiteralComponentType
The LiteralComponentType defines the way to provide an immutable
value to a local_variable.
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+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 0..1 | Defines the |
| | | | datatype. |
| | | | Default |
| | | | Value: |
| | | | 'string'. |
| | | | |
| value | string | 0..1 | The value of |
| | | | the literal |
| | | | component. If |
| | | | no value is |
| | | | specified the |
| | | | value is |
| | | | considered to |
| | | | be the empty |
| | | | string. |
+----------+--------------------------------+-------+---------------+
Table 31: LiteralComponentType Construct
33. ObjectComponentType
The ObjectComponentType defines the mechanism for retrieving OVAL
Item Entity values, specified by an OVAL Object, to provide one or
more values to a component of a local_variable or OVAL Function.
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+--------------+-------------------------+-------+------------------+
| Property | Type | Count | Description |
+--------------+-------------------------+-------+------------------+
| object_ref | oval:ObjectIDPattern | 1 | Specifies the |
| | | | identifier for |
| | | | the OVAL Object |
| | | | which the |
| | | | component |
| | | | refers. |
| | | | |
| item_field | oval:NonEmptyStringType | 1 | The name of the |
| | | | OVAL Item Entity |
| | | | to use for the |
| | | | value(s) of the |
| | | | OVAL Variable. |
| | | | |
| record_field | oval:NonEmptyStringType | 0..1 | Allows the |
| | | | retrieval of a |
| | | | specified OVAL |
| | | | field to be |
| | | | retrieved from |
| | | | an OVAL Item |
| | | | Entity that has |
| | | | a datatype of |
| | | | 'record'. |
+--------------+-------------------------+-------+------------------+
Table 32: ObjectComponentType Construct
34. VariableComponentType
The VariableComponentType defines the way to specify that the
value(s) of another OVAL Variable should be used as the value(s) for
a component of a local_variable or OVAL Function.
A variable component is a component that resolves to the value(s)
associated with the referenced OVAL Variable.
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+----------+------------------------+-------+-----------------------+
| Property | Type | Count | Description |
+----------+------------------------+-------+-----------------------+
| var_ref | oval:VariableIDPattern | 1 | Specifies the |
| | | | Identifier for the |
| | | | OVAL Variable to |
| | | | which the component |
| | | | refers. The var_ref |
| | | | property MUST refer |
| | | | to an existing OVAL |
| | | | Variable. Care must |
| | | | be taken to ensure |
| | | | that the referenced |
| | | | OVAL Variable does |
| | | | not result in a |
| | | | circular reference as |
| | | | it could result in an |
| | | | infinite loop when |
| | | | evaluated. |
+----------+------------------------+-------+-----------------------+
Table 33: VariableComponentType Construct
35. FunctionGroup
The FunctionGroup defines the possible OVAL Functions for use in OVAL
Content to manipulate collected data. OVAL Functions can be nested
within one another to achieve the case where one needs to perform
multiple functions on a collection of values.
+----------------+----------------------------+-------+-------------+
| Property | Type | Count | Description |
+----------------+----------------------------+-------+-------------+
| arithmetic | ArithmeticFunctionType | 0..1 | A function |
| | | | for |
| | | | performing |
| | | | basic math |
| | | | on numbers. |
| | | | |
| begin | BeginFunctionType | 0..1 | A function |
| | | | that |
| | | | ensures |
| | | | that a |
| | | | collected |
| | | | string |
| | | | starts with |
| | | | a specified |
| | | | string. |
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| | | | |
| concat | ConcatFunctionType | 0..1 | A function |
| | | | that |
| | | | combines |
| | | | multiple |
| | | | strings. |
| | | | |
| end | EndFunctionType | 0..1 | A function |
| | | | that |
| | | | determines |
| | | | whether a |
| | | | collected |
| | | | string ends |
| | | | with a |
| | | | specified |
| | | | string or |
| | | | not. |
| | | | |
| escape_regex | EscapeRegexFunctionType | 0..1 | A function |
| | | | that |
| | | | escapes all |
| | | | of the |
| | | | reserved |
| | | | regular |
| | | | expression |
| | | | characters |
| | | | in a |
| | | | string. |
| | | | |
| split | SplitFunctionType | 0..1 | A function |
| | | | that splits |
| | | | a string |
| | | | into parts, |
| | | | using a |
| | | | delimeter. |
| | | | |
| substring | SubstringFunctionType | 0..1 | A function |
| | | | that |
| | | | creates a |
| | | | substring |
| | | | from a |
| | | | value. |
| | | | |
| time_differenc | TimeDifferenceFunctionType | 0..1 | A function |
| e | | | that |
| | | | calculates |
| | | | the |
| | | | difference |
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| | | | between two |
| | | | times. |
| | | | |
| unique | UniqueFunctionType | 0..1 | A function |
| | | | that takes |
| | | | one or more |
| | | | components |
| | | | and removes |
| | | | any |
| | | | duplicate |
| | | | value from |
| | | | the set of |
| | | | components. |
| | | | |
| regex_capture | RegexCaptureFunctionType | 0..1 | A function |
| | | | that uses a |
| | | | regular |
| | | | expression |
| | | | to capture |
| | | | a substring |
| | | | of a |
| | | | collected |
| | | | string |
| | | | value. |
+----------------+----------------------------+-------+-------------+
Table 34: FunctionGroup Construct
36. ArithmeticFunctionType
The ArithmeticFunctionType defines a function that calculates a
given, simple mathematic operation between two or more values. This
function applies the specified mathematical operation on two or more
integer or float values. The result of this operation is a single
integer or float value, unless any of the sub-components resolve to
multiple values, in which case the result will be an array of values,
corresponding to the arithmetic operation applied to the Cartesian
product of the values.
In the case of mixed integers and floats, the result will be a float
value.
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+--------------------+---------------------+-------+----------------+
| Property | Type | Count | Description |
+--------------------+---------------------+-------+----------------+
| arithmetic_operati | ArithmeticEnumerati | 1 | The operation |
| on | on | | to perform. |
| | | | |
| values | ComponentGroup | 2..* | Any type from |
| | | | the ComponentG |
| | | | roup. |
+--------------------+---------------------+-------+----------------+
Table 35: ArithmeticFunctionType Construct
37. BeginFunctionType
The BeginFunctionType defines a function that ensures that the
specified values start with a specified character or string. This
function operates on a single sub-component of datatype string and
ensures that the specified value(s) start with the characters
specified in the character property. When a value does not start
with the specified characters, the function will prepend add the
complete set of characters from the character property to the string.
Otherwise, the string value will remain unchanged.
+-----------+----------------+-------+------------------------------+
| Property | Type | Count | Description |
+-----------+----------------+-------+------------------------------+
| character | string | 1 | The character or string to |
| | | | use for the function. |
| | | | |
| value | ComponentGroup | 1 | Any type from the |
| | | | ComponentGroup. |
+-----------+----------------+-------+------------------------------+
Table 36: BeginFunctionType Construct
38. ConcatFunctionType
The ConcatFunctionType defines a function that concatenates the
values specified together into a single string value. This function
combines the values of two or more sub-components into a single
string value. The function combines the sub-component values in the
order that they are specified. That is, the first sub-component
specified will always be at the beginning of the newly created string
value and the last sub-component will always be at the end of the
newly created string value.
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+----------+----------------+-------+-------------------------------+
| Property | Type | Count | Description |
+----------+----------------+-------+-------------------------------+
| values | ComponentGroup | 2..* | Any type from the |
| | | | ComponentGroup. |
+----------+----------------+-------+-------------------------------+
Table 37: ConcatFunctionType Construct
39. CountFunctionType
The CountFunctionType defines a function that counts the values
represented by one or more components as an integer. This function
determines the total number of values referenced by all of the
specified sub-components.
+----------+----------------+-------+-------------------------------+
| Property | Type | Count | Description |
+----------+----------------+-------+-------------------------------+
| values | ComponentGroup | 1..* | Any type from the |
| | | | ComponentGroup. |
+----------+----------------+-------+-------------------------------+
Table 38: CountFunctionType Construct
40. EndFunctionType
The EndFunctionType defines a function that ensures that the
specified values end with a specified character or string. This
function operates on a single sub-component of datatype string and
ensures that the specified value(s) end with the characters specified
in the character property. When a value does not end with the
specified characters, the function will add the complete set of
characters from the character property to the end of the string.
Otherwise, the string value will remain unchanged.
+-----------+----------------+-------+------------------------------+
| Property | Type | Count | Description |
+-----------+----------------+-------+------------------------------+
| character | string | 1 | The character or string to |
| | | | use for the function. |
| | | | |
| value | ComponentGroup | 1 | Any type from the |
| | | | ComponentGroup. |
+-----------+----------------+-------+------------------------------+
Table 39: EndFunctionType Construct
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41. EscapeRegexFunctionType
The EscapeRegexFunctionType defines a function that escapes all of
the regular expression reserved characters in a given string. This
function operates on a single sub-component, escaping reserved
regular expression characters for each sub-component value. The set
of metacharacters, in the Perl 5 regular expression syntax, which
must be escaped for this purpose is as follows, enclosed by single
quotes: '^$\.[](){}*+?|'. Please see the Regular Expression Support
section in [I-D.draft-cokus-sacm-oval-common-model] for more
information on the Perl 5 regular expression syntax that is supported
in the OVAL Language.
+----------+----------------+-------+-------------------------------+
| Property | Type | Count | Description |
+----------+----------------+-------+-------------------------------+
| value | ComponentGroup | 1 | Any type from the |
| | | | ComponentGroup. |
+----------+----------------+-------+-------------------------------+
Table 40: EscapeRegexFunctionType Construct
42. SplitFunctionType
The SplitFunctionType defines a function that splits a string value
into multiple values, based on a specified delimiter. This function
operates on a single sub-component and results in an array of values,
where each values is the splitting the subject string using the
specified delimiter.
If the sub-component being split includes a string that either begins
with or ends with the delimiter, there will be an empty string value
included either at the beginning or end, respectively.
If multiple instances of the delimiter appear consecutively, each
instance will result in an additional empty string value.
If the delimiter is not found in the subject string, the entire
subject string will be included in the result.
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+-----------+----------------+-------+------------------------------+
| Property | Type | Count | Description |
+-----------+----------------+-------+------------------------------+
| delimiter | string | 1 | The string to use as a |
| | | | delimiter. |
| | | | |
| value | ComponentGroup | 1 | Any type from the |
| | | | ComponentGroup. |
+-----------+----------------+-------+------------------------------+
Table 41: SplitFunctionType Construct
43. SubstringFunctionType
The SubstringFunctionType defines a function that takes a string
value and produces a value that contains a portion of the original
string.
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+------------------+----------------+-------+-----------------------+
| Property | Type | Count | Description |
+------------------+----------------+-------+-----------------------+
| substring_start | int | 1 | The starting index to |
| | | | use for the |
| | | | substring. This |
| | | | property is 1-based, |
| | | | meaning that a value |
| | | | of 1 represents the |
| | | | first character of |
| | | | the subject string. A |
| | | | value less than 1 is |
| | | | also interpreted as |
| | | | the first character |
| | | | in the subject |
| | | | string. If the |
| | | | substring_start |
| | | | property exceeds the |
| | | | length of the subject |
| | | | string an error MUST |
| | | | be reported. |
| | | | |
| substring_length | int | 1 | Represents the length |
| | | | of the substring to |
| | | | be taken from the |
| | | | source string, |
| | | | including the |
| | | | starting character. |
| | | | Any substring_length |
| | | | that exceeds the |
| | | | length of the string |
| | | | or is negative |
| | | | indicates to include |
| | | | all characters from |
| | | | the starting |
| | | | character until the |
| | | | end of the source |
| | | | string. |
| | | | |
| value | ComponentGroup | 1 | Any type from the |
| | | | ComponentGroup. |
+------------------+----------------+-------+-----------------------+
Table 42: SubstringFunctionType Construct
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44. TimeDifferenceFunctionType
The TimeDifferenceFunctionType defines a function that produces a
value containing the difference in seconds between two date-time
values. If a single sub-component is specified, then the time
difference is between the specified date-time and the current date-
time. The current time is the time at which the function is
evaluated. If two sub-components are specified, then the difference
is that between the two specified date-times.
+----------+---------------------------+-------+--------------------+
| Property | Type | Count | Description |
+----------+---------------------------+-------+--------------------+
| format_1 | DateTimeFormatEnumeration | 0..1 | The format for the |
| | | | first date-time |
| | | | value specified. |
| | | | Note: If |
| | | | specifying a |
| | | | single value, use |
| | | | format_1 to |
| | | | specify the |
| | | | implied current |
| | | | date-time. Default |
| | | | Value: |
| | | | 'year_month_day'. |
| | | | |
| format_2 | DateTimeFormatEnumeration | 0..1 | The format for the |
| | | | second date-time |
| | | | value specified. |
| | | | Note: If |
| | | | specifying a |
| | | | single value, use |
| | | | format_2 to |
| | | | specify the |
| | | | value's format, as |
| | | | format_1 is used |
| | | | for the implied |
| | | | current date-time. |
| | | | Default Value: |
| | | | 'year_month_day'. |
| | | | |
| value | ComponentGroup | 1..2 | Any type from the |
| | | | ComponentGroup. |
+----------+---------------------------+-------+--------------------+
Table 43: TimeDifferenceFunctionType Construct
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If a sub-component value does not conform to the format specified in
the DateTimeFormatEnumeration an error MUST be reported.
The datatype associated with the sub-components MUST be 'string' or
'int' depending on which date time format is specified. The result
of this function is always an integer. The following table states
which datatype MUST be used with which format from the
DateTimeFormatEnumeration.
+---------------------+-------------+
| Value | Description |
+---------------------+-------------+
| year_month_day | string |
| | |
| month_day_year | string |
| | |
| day_month_year | string |
| | |
| win_filetime | int |
| | |
| seconds_since_epoch | int |
+---------------------+-------------+
Table 44: DateTimeFormat Datatype Enumeration Table
45. UniqueFunctionType
The UniqueFunctionType defines a function that removes any duplicate
value from the set of values represented by one or more components.
This function takes one or more sub-components and removes any
duplicate values across the sub-components. A duplicate value is
defined as any value that is equal to another value when compared as
a string value.
+----------+----------------+-------+-------------------------------+
| Property | Type | Count | Description |
+----------+----------------+-------+-------------------------------+
| values | ComponentGroup | 1..* | Any type from the |
| | | | ComponentGroup |
+----------+----------------+-------+-------------------------------+
Table 45: UniqueFunctionType Construct
46. RegexCaptureFunctionType
The RegexCaptureFunctionType defines a function operating on a single
component, which extracts a substring from each of its values.
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The pattern property specifies a regular expression, which SHOULD
contain a single capturing sub-pattern (using parentheses). If the
regular expression contains multiple capturing sub-patterns, only the
first capture is used. If there are no capturing sub-patterns, the
result for each target string MUST be the empty string. Otherwise,
if the regular expression could match the target string in more than
one place, only the first match (and its first capture) is used. If
no matches are found in a target string, the result for that target
MUST be the empty string.
Note that a quantified capturing sub-pattern does not produce
multiple substrings. Standard regular expression semantics are such
that if a capturing sub-pattern is required to match multiple times
in order for the overall regular expression to match, the capture
produced is the last substring to have matched the sub-pattern.
If any of the Perl 5 regular expression syntax metacharacters are to
be used literally, then they must be escaped. The set of
metacharacters which must be escaped for this purpose is as follows,
enclosed by single quotes: '^$\.[](){}*+?|'. Please see the Regular
Expression Support section in [I-D.draft-cokus-sacm-oval-common-
model] for more information on the Perl 5 regular expression syntax
that is supported in the OVAL Language.
+----------+----------------+-------+-------------------------------+
| Property | Type | Count | Description |
+----------+----------------+-------+-------------------------------+
| pattern | string | 1 | The string to use as a |
| | | | regular expression pattern. |
| | | | |
| value | ComponentGroup | 1 | Any type from the |
| | | | ComponentGroup. |
+----------+----------------+-------+-------------------------------+
Table 46: RegexCaptureFunctionType Construct
47. ArithmeticEnumeration
The ArithmeticEnumeration defines an enumeration for the possible
values for the arithmetic function.
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+----------+---------------------------+
| Value | Description |
+----------+---------------------------+
| add | Indicates addition. |
| | |
| multiply | Indicates multiplication. |
+----------+---------------------------+
Table 47: Arithmetic Enumeration
48. DateTimeFormatEnumeration
The DateTimeFormatEnumeration defines an enumeration for the possible
values for the date-time values.
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+---------------------+---------------------------------------+
| Value | Description |
+---------------------+---------------------------------------+
| year_month_day | This value indicates a format that |
| | follows the following patterns: |
| | |
| | o yyyymmdd |
| | o yyyymmddThhmmss |
| | o yyyy/mm/dd hh:mm:ss |
| | o yyyy/mm/dd |
| | o yyyy-mm-dd hh:mm:ss |
| | o yyyy-mm-dd |
+---------------------+---------------------------------------+
| month_day_year | This value indicates a format that |
| | follows the following patterns: |
| | |
| | o mm/dd/yyyy hh:mm:ss |
| | o mm/dd/yyyy |
| | o mm-dd-yyyy hh:mm:ss |
| | o mm-dd-yyyy |
| | o NameOfMonth, dd yyyy hh:mm:ss |
| | o NameOfMonth, dd yyyy |
| | o AbreviatedNameOfMonth, |
| | dd yyyy hh:mm:ss |
| | o AbreviatedNameOfMonth, dd yyyy |
+---------------------+---------------------------------------+
| day_month_year | This value indicates a format that |
| | follows the following patterns: |
| | |
| | o dd/mm/yyyy hh:mm:ss |
| | o dd/mm/yyyy |
| | o dd-mm-yyyy hh:mm:ss |
| | o dd-mm-yyyy |
+---------------------+---------------------------------------+
| win_filetime | This value indicates a date-time that |
| | follows the windows file time |
| | format [WIN-FILETIME]. |
+---------------------+---------------------------------------+
| seconds_since_epoch | This value indicates a date-time that |
| | represents the time in seconds since |
| | the UNIX Epoch. The UNIX epoch is the |
| | time 00:00:00 UTC on January 1, 1970. |
+---------------------+---------------------------------------+
Figure 1: DateTimeFormat Enumeration
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49. FilterActionEnumeration
The FilterActionEnumeration defines an enumeration for the possible
values for filtering a set of items.
+---------+---------------------------------------------------------+
| Value | Description |
+---------+---------------------------------------------------------+
| include | A value that indicates to include matching items from |
| | the set. |
| | |
| exclude | A value that indicates to exclude matching items from |
| | the set. |
+---------+---------------------------------------------------------+
Table 48: FilterAction Enumeration
50. SetOperatorEnumeration
The SetOperatorEnumeration defines an enumeration for the possible
values defining a set.
+--------------+----------------------------------------------------+
| Value | Description |
+--------------+----------------------------------------------------+
| COMPLEMENT | A value that indicates to include only the |
| | elements from the first set that are not found in |
| | the second. |
| | |
| INTERSECTION | A value that indicates to include all of the |
| | values common to both sets. |
| | |
| UNION | A value that indicates to include all values found |
| | in either of the sets. |
+--------------+----------------------------------------------------+
Table 49: SetOperator Enumeration
51. EntityAttributeGroup
The EntityAttributeGroup defines a set of attributes that are common
to all OVAL Object and OVAL State entities.
Some OVAL Entities provide additional restrictions on these
attributes and their allowed values.
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+-----------+---------------------------+-------+-------------------+
| Property | Type | Count | Description |
+-----------+---------------------------+-------+-------------------+
| datatype | oval:DatatypeEnumeration | 0..1 | The datatype for |
| | | | the entity. |
| | | | Default Value: |
| | | | 'string'. |
| | | | |
| operation | oval:OperationEnumeration | 0..1 | The operation |
| | | | that is to be |
| | | | performed on the |
| | | | entity. Default |
| | | | Value: 'equals'. |
| | | | |
| mask | boolean | 0..1 | Tells the data |
| | | | collection that |
| | | | this entity |
| | | | contains |
| | | | sensitive data. |
| | | | Data marked with |
| | | | mask='true' |
| | | | should be used |
| | | | only in the |
| | | | evaluation, and |
| | | | not be included |
| | | | in the results. |
| | | | Default Value: |
| | | | 'false'. |
| | | | |
| var_ref | oval:VariableIDPattern | 0..1 | Points to a |
| | | | variable |
| | | | Identifier within |
| | | | the OVAL document |
| | | | which should be |
| | | | used to calculate |
| | | | the entity's |
| | | | value. |
| | | | |
| var_check | oval:CheckEnumeration | 0..1 | Directs how to |
| | | | either collect |
| | | | data or evaluate |
| | | | state for the |
| | | | entity. |
+-----------+---------------------------+-------+-------------------+
Table 50: EntityAttributeGroup
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52. EntitySimpleBaseType
The EntitySimpleBaseType is an abstract type that defines a base type
for all simple entities. Entities represent the individual
properties for OVAL Objects and OVAL States.
+------------+----------------------+-------+-----------------------+
| Property | Type | Count | Description |
+------------+----------------------+-------+-----------------------+
| attributes | EntityAttributeGroup | 1 | The standard |
| | | | attributes available |
| | | | to all entities. |
| | | | |
| value | String | 0..1 | The value of the |
| | | | entity. An empty |
| | | | string value MUST be |
| | | | used when referencing |
| | | | an OVAL Variable. |
+------------+----------------------+-------+-----------------------+
Table 51: EntitySimpleBaseType Construct
53. EntityComplexBaseType
The EntityComplexBaseType is an abstract type that defines a base
type for all complex entities. Entities represent the individual
properties for OVAL Objects and OVAL States.
+------------+----------------------+-------+-----------------------+
| Property | Type | Count | Description |
+------------+----------------------+-------+-----------------------+
| attributes | EntityAttributeGroup | 1 | The standard |
| | | | attributes available |
| | | | to all entities. |
+------------+----------------------+-------+-----------------------+
Table 52: EntityComplexBaseType Construct
54. EntityObjectIPAddressType
The EntityObjectIPAddressType extends the EntitySimpleBaseType and
describes an IPv4 or IPv6 IP address.
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+----------+-----------------+-------+------------------+
| Property | Type | Count | Description |
| | | | |
+----------+-----------------+-------+------------------+
| datatype | oval: | 1 | Possible |
| | SimpleDatatype | | values: |
| | Enumeration | | |
| | | | o 'ipv4_address' |
| | | | o 'ipv6_address' |
| | | | |
| | | | Also allows an |
| | | | empty string |
| | | | value. |
+----------+-----------------+-------+------------------+
Figure 2: EntityObjectIPAddressType Construct
55. EntityObjectIPAddressStringType
The EntityObjectIPAddressStringType extends the EntitySimpleBaseType
and describes an IPv4 or IPv6 IP address or a string representation
of the address.
+----------+-----------------+-------+------------------+
| Property | Type | Count | Description |
| | | | |
+----------+-----------------+-------+------------------+
| datatype | oval: | 1 | Possible |
| | SimpleDatatype | | values: |
| | Enumeration | | |
| | | | o 'ipv4_address' |
| | | | o 'ipv6_address' |
| | | | o 'string' |
| | | | |
| | | | Also allows an |
| | | | empty string |
| | | | value. |
+----------+-----------------+-------+------------------+
Figure 3: EntityObjectIPAddressStringType Construct
56. EntityObjectAnySimpleType
The EntityObjectAnySimpleType extends the EntitySimpleBaseType and
describes any simple data.
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+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | Any simple |
| | | | datatype. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 53: EntityObjectAnySimpleType Construct
57. EntityObjectBinaryType
The EntityObjectBinaryType extends the EntitySimpleBaseType and
describes any simple binary data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'binary'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 54: EntityObjectBinaryType Construct
58. EntityObjectBoolType
The EntityObjectBoolType extends the EntitySimpleBaseType and
describes any simple boolean data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'boolean'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 55: EntityObjectBoolType Construct
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59. EntityObjectFloatType
The EntityObjectFloatType extends the EntitySimpleBaseType and
describes any simple float data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'float'. Also |
| | | | allows an |
| | | | empty string |
| | | | value. |
+----------+--------------------------------+-------+---------------+
Table 56: EntityObjectFloatType Construct
60. EntityObjectIntType
The EntityObjectIntType extends the EntitySimpleBaseType and
describes any simple integer data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'int'. Also |
| | | | allows an |
| | | | empty string |
| | | | value. |
+----------+--------------------------------+-------+---------------+
Table 57: EntityObjectIntType Construct
61. EntityObjectStringType
The EntityObjectStringType extends the EntitySimpleBaseType and
describes any simple string data.
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+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'string'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 58: EntityObjectStringType Construct
62. EntityObjectVersionType
The EntityObjectVersionType extends the EntitySimpleBaseType and
describes any simple version data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'version'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 59: EntityObjectVersionType Construct
63. EntityObjectRecordType
The EntityObjectRecordType extends the EntityComplexBaseType and
allows assertions to be made on entities with uniquely named fields.
It is intended to be used to assess the results of things such as SQL
statements and similar data.
+-----------+---------------------------------+-------+-------------+
| Property | Type | Count | Description |
+-----------+---------------------------------+-------+-------------+
| datatype | oval:ComplexDatatypeEnumeration | 1 | This value |
| | | | is fixed as |
| | | | 'record'. |
| | | | |
| operation | oval:OperationEnumeration | 0..1 | This value |
| | | | is fixed as |
| | | | 'equals'. |
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| | | | |
| mask | boolean | 0..1 | Tells the |
| | | | data |
| | | | collection |
| | | | that this |
| | | | entity |
| | | | contains |
| | | | sensitive |
| | | | data. Data |
| | | | marked with |
| | | | mask='true' |
| | | | should be |
| | | | used only |
| | | | in the |
| | | | evaluation, |
| | | | and not be |
| | | | included in |
| | | | the |
| | | | results. |
| | | | Note that |
| | | | when the |
| | | | mask |
| | | | property is |
| | | | set to |
| | | | 'true', all |
| | | | child field |
| | | | elements |
| | | | must be |
| | | | masked |
| | | | regardless |
| | | | of the |
| | | | child |
| | | | field's |
| | | | mask |
| | | | attribute |
| | | | value. |
| | | | Default |
| | | | Value: |
| | | | 'false'. |
| | | | |
| var_ref | oval:VariableIDPattern | 0..1 | Use of this |
| | | | property is |
| | | | prohibited. |
| | | | |
| var_check | oval:CheckEnumeration | 0..1 | Use of this |
| | | | property is |
| | | | prohibited. |
+-----------+---------------------------------+-------+-------------+
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Table 60: EntityObjectRecordType Construct
64. EntityObjectFieldType
The EntityObjectFieldType defines an entity type that captures the
details of a single field for a record.
+------------+----------------------+-------+-----------------------+
| Property | Type | Count | Description |
+------------+----------------------+-------+-----------------------+
| attributes | EntityAttributeGroup | 1 | The standard |
| | | | attributes available |
| | | | to all entities. |
| | | | |
| name | string | 1 | The name of the |
| | | | field. Names MUST be |
| | | | all lower case |
| | | | characters in the |
| | | | range of a-z. Names |
| | | | MUST be unique within |
| | | | a record. |
| | | | |
| value | string | 0..1 | The value of the |
| | | | field. An empty |
| | | | string value MUST be |
| | | | used when referencing |
| | | | an OVAL Variable. |
+------------+----------------------+-------+-----------------------+
Table 61: EntityObjectFieldType Construct
65. EntityStateSimpleBaseType
The EntityStateSimpleBaseType extends the EntitySimpleBaseType and
defines a simple base type for OVAL States.
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+--------------+-----------------------+-------+--------------------+
| Property | Type | Count | Description |
+--------------+-----------------------+-------+--------------------+
| entity_check | oval:CheckEnumeration | 0..1 | Defines how to |
| | | | handle multiple |
| | | | item entities with |
| | | | the same name. |
| | | | Default Value: |
| | | | 'all'. |
| | | | |
| value | string | 0..1 | The value of the |
| | | | entity. An empty |
| | | | string value MUST |
| | | | be used when |
| | | | referencing an |
| | | | OVAL Variable. |
+--------------+-----------------------+-------+--------------------+
Table 62: EntityStateSimpleBaseType Construct
66. EntityStateComplexBaseType
The EntityStateComplexBaseType extends the EntityComplexBaseType
defines a complex base type for OVAL States.
+--------------+-----------------------+-------+--------------------+
| Property | Type | Count | Description |
+--------------+-----------------------+-------+--------------------+
| entity_check | oval:CheckEnumeration | 0..1 | Defines how to |
| | | | handle multiple |
| | | | item entities with |
| | | | the same name. |
| | | | Default Value: |
| | | | 'all'. |
+--------------+-----------------------+-------+--------------------+
Table 63: EntityStateComplexBaseType Construct
67. EntityStateIPAddressType
The EntityStateIPAddressType extends the EntityStateSimpleBaseType
and describes an IPv4 or IPv6 IP address.
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+----------+-----------------+-------+------------------+
| Property | Type | Count | Description |
| | | | |
+----------+-----------------+-------+------------------+
| datatype | oval: | 1 | Possible |
| | SimpleDatatype | | values: |
| | Enumeration | | |
| | | | o 'ipv4_address' |
| | | | o 'ipv6_address' |
| | | | |
| | | | Also allows an |
| | | | empty string |
| | | | value. |
+----------+-----------------+-------+------------------+
Figure 4: EntityStateIPAddressType Construct
68. EntityStateIPAddressStringType
The EntityStateIPAddressStringType extends the
EntityStateSimpleBaseType and describes an IPv4 or IPv6 IP address or
a string representation of the address.
+----------+-----------------+-------+------------------+
| Property | Type | Count | Description |
| | | | |
+----------+-----------------+-------+------------------+
| datatype | oval: | 1 | Possible |
| | SimpleDatatype | | values: |
| | Enumeration | | |
| | | | o 'ipv4_address' |
| | | | o 'ipv6_address' |
| | | | o 'string' |
| | | | |
| | | | Also allows an |
| | | | empty string |
| | | | value. |
+----------+-----------------+-------+------------------+
Figure 5: EntityStateIPAddressStringType Construct
69. EntityStateAnySimpleType
The EntityStateAnySimpleType extends the EntityStateSimpleBaseType
and describes any simple data.
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+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | Any simple |
| | | | datatype. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 64: EntityStateAnySimpleType Construct
70. EntityStateBinaryType
The EntityStateBinaryType extends the EntityStateSimpleBaseType and
describes any simple binary data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'binary'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 65: EntityStateBinaryType Construct
71. EntityStateBoolType
The EntityStateBoolType extends the EntityStateSimpleBaseType and
describes any simple boolean data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'boolean'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 66: EntityStateBoolType Construct
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72. EntityStateFloatType
The EntityStateFloatType extends the EntityStateSimpleBaseType and
describes any simple float data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'float'. Also |
| | | | allows an |
| | | | empty string |
| | | | value. |
+----------+--------------------------------+-------+---------------+
Table 67: EntityStateFloatType Construct
73. EntityStateIntType
The EntityStateIntType extends the EntityStateSimpleBaseType and
describes any simple integer data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'int'. Also |
| | | | allows an |
| | | | empty string |
| | | | value. |
+----------+--------------------------------+-------+---------------+
Table 68: EntityStateIntType Construct
74. EntityStateEVRStringType
The EntityStateEVRStringType extends the EntityStateSimpleBaseType
and describes an EPOCH:VERSION-RELEASE string data.
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+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'evr_string'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 69: EntityStateEVRStringType Construct
75. EntityStateDebianEVRStringType
The EntityStateDebianEVRStringType extends the
EntityStateSimpleBaseType and describes an EPOCH:UPSTREAM_VERSION-
DEBIAN_REVISION string data for a Debian package.
+---------+----------------------------+-------+--------------------+
| Propert | Type | Count | Description |
| y | | | |
+---------+----------------------------+-------+--------------------+
| datatyp | oval:SimpleDatatypeEnumera | 1 | This value is |
| e | tion | | fixed as 'debian_e |
| | | | vr_string'. Also |
| | | | allows an empty |
| | | | string value. |
+---------+----------------------------+-------+--------------------+
Table 70: EntityStateDebianEVRStringType Construct
76. EntityStateVersionType
The EntityStateVersionType extends the EntityStateSimpleBaseType and
describes a version string data.
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+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'version'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 71: EntityStateVersionType Construct
77. EntityStateFileSetRevisionType
The EntityStateFileSetRevisionType extends the
EntityStateSimpleBaseType and describes a file set revision string
data.
+---------+----------------------------+-------+--------------------+
| Propert | Type | Count | Description |
| y | | | |
+---------+----------------------------+-------+--------------------+
| datatyp | oval:SimpleDatatypeEnumera | 1 | This value is |
| e | tion | | fixed as 'fileset_ |
| | | | revision'. Also |
| | | | allows an empty |
| | | | string value. |
+---------+----------------------------+-------+--------------------+
Table 72: EntityStateFileSetRevisionType Construct
78. EntityStateIOSVersionType
The EntityStateIOSVersionType extends the EntityStateSimpleBaseType
and describes a Cisco IOS version string data.
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+----------+-----------------+-------+------------------+
| Property | Type | Count | Description |
| | | | |
+----------+-----------------+-------+------------------+
| datatype | oval: | 1 | Possible |
| | SimpleDatatype | | values: |
| | Enumeration | | |
| | | | o 'ios_version' |
| | | | o 'string' |
| | | | |
| | | | The string |
| | | | type is an |
| | | | option in |
| | | | order to allow |
| | | | use of regular |
| | | | expressions. |
+----------+-----------------+-------+------------------+
Figure 6: EntityStateIOSVersionType Construct
79. EntityStateStringType
The EntityStateStringType extends the EntitySimpleBaseType and
describes any simple string data.
+----------+--------------------------------+-------+---------------+
| Property | Type | Count | Description |
+----------+--------------------------------+-------+---------------+
| datatype | oval:SimpleDatatypeEnumeration | 1 | This value is |
| | | | fixed as |
| | | | 'string'. |
| | | | Also allows |
| | | | an empty |
| | | | string value. |
+----------+--------------------------------+-------+---------------+
Table 73: EntityStateStringType Construct
80. EntityStateRecordType
The EntityStateRecordType extends the EntityStateComplexBaseType and
allows assertions to be made on entities with uniquely named fields.
It is intended to be used to assess the results of things such as SQL
statements and similar data.
+-----------+---------------------------------+-------+-------------+
| Property | Type | Count | Description |
+-----------+---------------------------------+-------+-------------+
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| datatype | oval:ComplexDatatypeEnumeration | 1 | This value |
| | | | is fixed as |
| | | | 'record'. |
| | | | |
| operation | oval:OperationEnumeration | 0..1 | This value |
| | | | is fixed as |
| | | | 'equals'. |
| | | | |
| mask | boolean | 0..1 | Tells the |
| | | | data |
| | | | collection |
| | | | that this |
| | | | entity |
| | | | contains |
| | | | sensitive |
| | | | data. Data |
| | | | marked with |
| | | | mask='true' |
| | | | should be |
| | | | used only |
| | | | in the |
| | | | evaluation, |
| | | | and not be |
| | | | included in |
| | | | the |
| | | | results. |
| | | | Note that |
| | | | when the |
| | | | mask |
| | | | property is |
| | | | set to |
| | | | 'true', all |
| | | | child field |
| | | | elements |
| | | | must be |
| | | | masked |
| | | | regardless |
| | | | of the |
| | | | child |
| | | | field's |
| | | | mask |
| | | | attribute |
| | | | value. |
| | | | Default |
| | | | Value: |
| | | | 'false'. |
| | | | |
| var_ref | oval:VariableIDPattern | 0..1 | Use of this |
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| | | | property is |
| | | | prohibited. |
| | | | |
| var_check | oval:CheckEnumeration | 0..1 | Use of this |
| | | | property is |
| | | | prohibited. |
+-----------+---------------------------------+-------+-------------+
Table 74: EntityStateRecordType Construct
81. EntityStateFieldType
The EntityStateFieldType defines an entity type that captures the
details of a single field for a record.
+------------+----------------------+-------+-----------------------+
| Property | Type | Count | Description |
+------------+----------------------+-------+-----------------------+
| attributes | EntityAttributeGroup | 1 | The standard |
| | | | attributes available |
| | | | to all entities. |
| | | | |
| name | string | 1 | The name of the |
| | | | field. Names MUST be |
| | | | all lower case |
| | | | characters in the |
| | | | range of a-z. Names |
| | | | MUST be unique within |
| | | | a record. |
| | | | |
| value | string | 0..1 | The value of the |
| | | | field. An empty |
| | | | string value MUST be |
| | | | used when referencing |
| | | | an OVAL Variable. |
+------------+----------------------+-------+-----------------------+
Table 75: EntityStateFieldType Construct
82. OVAL Definitions Model Schema
The following XML Schema implements the OVAL Definitions Model.
The following is a
description of the elements, types, and
attributes that compose the core schema for
encoding Open Vulnerability and Assessment
Language (OVAL) Definitions. Some of the
objects defined here are extended and
enhanced by individual component schemas,
which are described in separate documents.
Each of the elements, types, and attributes
that make up the Core Definition Schema are
described in detail and should provide the
information necessary to understand what
each represents. This document is intended
for developers and assumes some familiarity
with XML. A high level description of the
interaction between these objects is not
outlined here.
Core Definition
5.11.1
4/22/2015 09:00:00 AM
Copyright (C) 2010 United States Government.
All Rights Reserved.
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The oval_definitions
element is the root of an OVAL Definition
Document. Its purpose is to bind together
the major sections of a document -
generator, definitions, tests, objects,
states, and variables - which are the
children of the root
element.
A valid OVAL Definition document
must contain at least one
definitions, tests, objects, states,
or variables element. The optional
definitions, tests, objects, states,
and variables sections define the
specific characteristics that should
be evaluated on a system to
determine the truth values of the
OVAL Definition Document. To be
valid though, at least one
definitions, tests, objects, states,
or variables element must be
present.
The required
generator section provides
information about when the
definition file was compiled and
under what
version.
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The optional
definitions section contains 1 or
more
definitions.
The optional tests
section contains 1 or more
tests.
The optional
objects section contains 1 or more
objects.
The optional states
section contains 1 or more
states.
The optional
variables section contains 1 or more
variables.
The optional
Signature element allows an XML
Signature as defined by the W3C to
be attached to the document. This
allows authentication and data
integrity to be provided to the
user. Enveloped signatures are
supported. More information about
the official W3C Recommendation
regarding XML digital signatures can
be found at
http://www.w3.org/TR/xmldsig-core/.
Enforce uniqueness
amongst the ids differentiating the
individual definition
elements.
Enforce uniqueness
amongst the ids differentiating the
individual test
elements.
Enforce uniqueness
amongst the ids differentiating the
individual object
elements.
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Enforce uniqueness
amongst the ids differentiating the
individual state
elements.
Enforce uniqueness
amongst the ids differentiating the
individual variable
elements.
Requires each
definition reference to refer to a valid
definition id.
Requires each test
reference to refer to a valid test
id.
Requires each object
reference to refer to a valid object
id.
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Requires each state
reference to refer to a valid state
id.
Requires each variable
reference to refer to a valid variable
id.
Require each object
reference in a set element to refer to a
valid object id.
Require each filter in
a set element to refer to a valid state
id.
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The notes element is a
container for one or more note child
elements. It exists for
backwards-compatibility purposes, for the
pre-5.11.0 oval-def:NotesType, which has
been replaced by the oval:notes element in
5.11.1.
5.11.1
Replaced by the oval:notes
element.
This object has been
deprecated and may be removed in a
future version of the
language.
DEPRECATED
ELEMENT: parent ID:
The DefinitionsType
complex type is a container for one or
more definition elements. Each definition
element describes a single OVAL
Definition. Please refer to the
description of the DefinitionType for more
information about an individual
definition.
The definition element
represents the globally defined element of
type DefinitionType. For more information
please see the documentation on the
DefinitionType.
The DefinitionType
defines a single OVAL Definition. A
definition is the key structure in OVAL.
It is analogous to the logical sentence or
proposition: if a computer's state matches
the configuration parameters laid out in
the criteria, then that computer exhibits
the state described. The DefinitionType
contains a section for various metadata
related elements that describe the
definition. This includes a description,
version, affected system types, and
reference information. The notes section
of a definition should be used to hold
information that might be helpful to
someone examining the technical aspects of
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the definition. For example, why certain
tests have been included in the criteria,
or maybe a link to where further
information can be found. The
DefinitionType also (unless the definition
is deprecated) contains a criteria child
element that joins individual tests
together with a logical operator to
specify the specific computer state being
described.
The required id attribute
is the OVAL-ID of the Definition. The form
of an OVAL-ID must follow the specific
format described by the
oval:DefinitionIDPattern. The required
version attribute holds the current
version of the definition. Versions are
integers, starting at 1 and incrementing
every time a definition is modified. The
required class attribute indicates the
specific class to which the definition
belongs. The class gives a hint to a user
so they can know what the definition
writer is trying to say. See the
definition of oval-def:ClassEnumeration
for more information about the different
valid classes. The optional deprecated
attribute signifies that an id is no
longer to be used or referenced but the
information has been kept around for
historic purposes.
When the deprecated
attribute is set to true, the definition
is considered to be deprecated. The
criteria child element of a deprecated
definition is optional. If a deprecated
definition does not contain a criteria
child element, the definition must
evaluate to "not evaluated". If a
deprecated definition contains a criteria
child element, an interpreter should
evaluate the definition as if it were not
deprecated, but an interpreter may
evaluate the definition to "not
evaluated".
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A
valid OVAL Definition must contain a
criteria unless the definition is a
deprecated definition.
Each affected
element must have a unique family
attribute value.
The MetadataType complex
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type contains all the metadata available
to an OVAL Definition. This metadata is
for informational purposes only and is not
part of the criteria used to evaluate
machine state. The required title child
element holds a short string that is used
to quickly identify the definition to a
human user. The affected metadata item
contains information about the system(s)
for which the definition has been written.
Remember that this is just metadata and
not part of the criteria. Please refer to
the AffectedType description for more
information. The required description
element contains a textual description of
the configuration state being addressed by
the OVAL Definition. In the case of a
definition from the vulnerability class,
the reference is usually the Common
Vulnerability and Exposures (CVE)
Identifier, and this description field
corresponds with the CVE
description.
Additional metadata is
also allowed although it is not part of
the official OVAL Schema. Individual
organizations can place metadata items
that they feel are important and these
will be skipped during the validation. All
OVAL really cares about is that the stated
metadata items are
there.
Each affected
platform element must have a unique
value.
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Each affected
product element must have a unique
value.
Each OVAL Definition is
written to evaluate a certain type of
system(s). The family, platform(s), and
product(s) of this target are described by
the AffectedType whose main purpose is to
provide hints for tools using OVAL
Definitions. For instance, to help a
reporting tool only use Windows
definitions, or to preselect only Red Hat
definitions to be evaluated. Note, the
inclusion of a particular platform or
product does not mean the definition is
physically checking for the existence of
the platform or product. For the actual
test to be performed, the correct test
must still be included in the definition's
criteria section.
The AffectedType complex
type details the specific system,
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application, subsystem, library, etc. for
which a definition has been written. If a
definition is not tied to a specific
product, then this element should not be
included. The absence of the platform or
product element can be thought of as
definition applying to all platforms or
products. The inclusion of a particular
platform or product does not mean the
definition is physically checking for the
existence of the platform or product. For
the actual test to be performed, the
correct test must still be included in the
definition's criteria section. To increase
the utility of this element, care should
be taken when assigning and using strings
for product names. The schema places no
restrictions on the values that can be
assigned, potentially leading to many
different representations of the same
value. For example, 'Internet Explorer'
and 'IE' might be used to refer to the
same product. The current convention is to
fully spell out all terms, and avoid the
use of abbreviations at all
costs.
Please note that the
AffectedType will change in future
versions of OVAL in order to support the
Common Platform Enumeration
(CPE).
The ReferenceType complex
type links the OVAL Definition to a
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definitive external reference. For
example, CVE Identifiers are used for
referencing vulnerabilities. The intended
purpose for this reference is to link the
definition to a variety of other sources
that address the same issue being
specified by the OVAL
Definition.
The required source
attribute specifies where the reference is
coming from. In other words, it identifies
the reference repository being used. The
required ref_id attribute is the external
id of the reference. The optional ref_url
attribute is the URL to the
reference.
The CriteriaType complex
type describes a container for a set of
sub criteria, criteria, criterion, or
extend_definition elements allowing
complex logical trees to be constructed.
Each referenced test is represented by a
criterion element. Please refer to the
description of the CriterionType for more
information about and individual criterion
element. The optional extend_definition
element allows existing definitions to be
included in the criteria. Refer to the
description of the ExtendDefinitionType
for more information.
The required operator
attribute provides the logical operator
that binds the different statements inside
a criteria together. The optional negate
attribute signifies that the result of the
criteria as a whole should be negated
during analysis. For example, consider a
criteria that evaluates to TRUE if certain
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software is installed. By negating this
test, it now evaluates to TRUE if the
software is NOT installed. The optional
comment attribute provides a short
description of the
criteria.
The optional
applicability_check attribute provides a
Boolean flag that when true indicates that
the criteria is being used to determine
whether the OVAL Definition applies to a
given system.
The CriterionType complex
type identifies a specific test to be
included in the definition's
criteria.
The required test_ref
attribute is the actual id of the test
being referenced. The optional negate
attribute signifies that the result of an
individual test should be negated during
analysis. For example, consider a test
that evaluates to TRUE if a specific patch
is installed. By negating this test, it
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now evaluates to TRUE if the patch is NOT
installed. The optional comment attribute
provides a short description of the
specified test and should mirror the
comment attribute of the actual
test.
The optional
applicability_check attribute provides a
Boolean flag that when true indicates that
the criterion is being used to determine
whether the OVAL Definition applies to a
given system.
The ExtendDefinitionType
complex type allows existing definitions
to be extended by another definition. This
works by evaluating the extended
definition and then using the result
within the logical context of the
extending definition.
The required
definition_ref attribute is the actual id
of the definition being extended. The
optional negate attribute signifies that
the result of an extended definition
should be negated during analysis. For
example, consider a definition that
evaluates TRUE if certainsoftware is
installed. By negating the definition, it
now evaluates to TRUE if the software is
NOT installed. The optional comment
attribute provides a short description of
the specified definition and should mirror
the title metadata of the extended
definition.
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The optional
applicability_check attribute provides a
Boolean flag that when true indicates that
the extend_definition is being used to
determine whether the OVAL Definition
applies to a given
system.
The TestsType complex
type is a container for one or more test
child elements. Each test element
describes a single OVAL Test. Please refer
to the description of the TestType for
more information about an individual
test.
The test element is an
abstract element that is meant to be
extended (via substitution groups) by the
individual tests found in the component
schemas. An OVAL Test is used to compare
an object(s) against a defined state. An
actual test element is not valid. The use
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of this abstract class simplifies the OVAL
schema by allowing individual tests to
inherit the optional notes child element,
and the id and comment attributes from the
base TestType. Please refer to the
description of the TestType complex type
for more information.
The base type of every
test includes an optional notes element
and several attributes. The notes section
of a test should be used to hold
information that might be helpful to
someone examining the technical aspects of
the test. For example, why certain values
have been used by the test, or maybe a
link to where further information can be
found. Please refer to the description of
the NotesType complex type for more
information about the notes element. The
required comment attribute provides a
short description of the test. The
optional deprecated attribute signifies
that an id is no longer to be used or
referenced but the information has been
kept around for historic
purposes.
The required id attribute
uniquely identifies each test, and must
conform to the format specified by the
TestIdPattern simple type. The required
version attribute holds the current
version of the test. Versions are
integers, starting at 1 and incrementing
every time a test is
modified.
The optional
check_existence attribute specifies how
many items in the set defined by the OVAL
Object must exist for the test to evaluate
to true. The default value for this
attribute is 'at_least_one_exists'
indicating that by default the test may
evaluate to true if at least one item
defined by the OVAL Object exists on the
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system. For example, if a value of
'all_exist' is given, every item defined
by the OVAL Object must exist on the
system for the test to evaluate to true.
If the OVAL Object uses a variable
reference, then every value of that
variable must exist. Note that a pattern
match defines a unique set of matching
items found on a system. So when
check_existence = 'all_exist' and a regex
matches anything on a system the test will
evaluate to true (since all matching
objects on the system were found on the
system). When check_existence =
'all_exist' and a regex does not match
anything on a system the test will
evaluate to false.
The required check
attribute specifies how many items in the
set defined by the OVAL Object (ignoring
items with a status of Does Not Exist)
must satisfy the state requirements. For
example, should the test check that all
matching files have a specified version or
that at least one file has the specified
version? The valid check values are
explained in the description of the
CheckEnumeration simple type. Note that if
the test does not contain any references
to OVAL States, then the check attribute
has no meaning and can be ignored during
evaluation.
An OVAL Test evaluates to
true if both the check_existence and check
attributes are satisfied during
evaluation. The evaluation result for a
test is determined by first evaluating the
check_existence attribute. If the result
of evaluating the check_existence
attribute is true then the check attribute
is evaluated. An interpreter may choose to
always evaluate both the check_existence
and the check attributes, but once the
check_existence attribute evaluation has
resulted in false the overall test result
after evaluating the check attribute will
not be affected.
The optional
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state_operator attribute provides the
logical operator that combines the
evaluation results from each referenced
state on a per item basis. Each matching
item is compared to each referenced state.
The result of comparing each state to a
single item is combined based on the
specified state_operator value to
determine one result for each item.
Finally, the results for each item are
combined based on the specified check
value. Note that if the test does not
contain any references to OVAL States,
then the state_operator attribute has no
meaning and can be ignored during
evaluation. Referencing multiple states in
one test allows ranges of possible values
to be expressed. For example, one state
can check that a value greater than 8 is
found and another state can check that a
value of less than 16 is found. In this
example the referenced states are combined
with a state_operator = 'AND' indicating
that the conditions of all referenced
states must be satisfied and that the
value must be between 8 AND 16. The valid
state_operation values are explained in
the description of the OperatorEnumeration
simple type.
- No
state should be referenced when
check_existence has a value of
'none_exist'.
The ObjectRefType complex
type defines an object reference to be
used by OVAL Tests that are defined in the
component schemas. The required object_ref
attribute specifies the id of the OVAL
Object being
referenced.
The StateRefType complex
type defines a state reference to be used
by OVAL Tests that are defined in the
component schemas. The required state_ref
attribute specifies the id of the OVAL
State being
referenced.
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The ObjectsType complex
type is a container for one or more object
child elements. Each object element
provides details that define a unique set
of matching items to be used by an OVAL
Test. Please refer to the description of
the object element for more information
about an individual
object.
The object element is an
abstract element that is meant to be
extended (via substitution groups) by the
objects found in the component schemas. An
actual object element is not valid. The
use of this abstract element simplifies
the OVAL schema by allowing individual
objects to inherit any common elements and
attributes from the base ObjectType.
Please refer to the description of the
ObjectType complex type for more
information.
An object is used to
identify a set of items to collect. The
author of a schema object must define
sufficient object entities to allow a user
to identify a unique item to be
collected.
A simple object typically
results in a single file, process, etc
being identified. But through the use of
pattern matches, sets, and variables,
multiple matching items can be identified.
The set of items matching the object can
then be used by an OVAL test and compared
against an OVAL state.
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The base type of every
object includes an optional notes element.
The notes element of an object should be
used to hold information that might be
helpful to someone examining the technical
aspects of the object. For example, why
certain values have been used, or maybe a
link to where further information can be
found. Please refer to the description of
the NotesType complex type for more
information about the notes
element.
The required id attribute
uniquely identifies each object, and must
conform to the format specified by the
ObjectIdPattern simple type. The required
version attribute holds the current
version of the object element. Versions
are integers, starting at 1 and
incrementing every time an object is
modified. The optional comment attribute
provides a short description of the
object. The optional deprecated attribute
signifies that an id is no longer to be
used or referenced but the information has
been kept around for historic
purposes.
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The set element enables
complex objects to be described. It is a
recursive element in that each set element
can contain additional set elements as
children. Each set element defines
characteristics that produce a matching
unique set of items. This set of items is
defined by one or two references to OVAL
Objects that provide the criteria needed
to collect a set of system items. These
items can have one or more filters applied
to allow a subset of those items to be
specifically included or excluded from the
overall set of items.
The set element's
object_reference refers to an existing
OVAL Object. The set element's filter
element provides a reference to an
existing OVAL State and includes an
optional action attribute. The filter's
action attribute allows the author to
specify whether matching items should be
included or excluded from the overall set.
The default filter action is to exclude
all matching items. In other words, the
filter can be thought of filtering items
out by default.
Each filter is applied to
the items identified by each OVAL Object
before the set_operator is applied. For
example, if an object_reference points to
an OVAL Object that identifies every file
in a certain directory, a filter might be
set up to limit the object set to only
those files with a size less than 10 KB.
If multiple filters are provided, then
each filter is applied to the set of items
identified by the OVAL Object. Care must
be taken to ensure that conflicting
filters are not applied. It is possible to
exclude all items with a size of 10 KB and
then include only items with a size of 10
KB. This example would result in the empty
set.
The required set_operator
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attribute defines how different child sets
are combined to form the overall unique
set of objects. For example, does one take
the union of different sets or the
intersection? For a description of the
valid values please refer to the
SetOperatorEnumeration simple
type.
- Each object referenced by the
set must be of the same type as
parent object
- Each
object referenced by the set must be
of the same type as parent
object
- Each
object referenced by the set must be
of the same type as parent
object
The filter element
provides a reference to an existing OVAL
State and includes an optional action
attribute. The action attribute is used to
specify whether items that match the
referenced OVAL State will be included in
the resulting set or excluded from the
resulting set.
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The StatesType complex
type is a container for one or more state
child elements. Each state provides
details about specific characteristics
that can be used during an evaluation of
an object. Please refer to the description
of the state element for more information
about an individual
state.
The state element is an
abstract element that is meant to be
extended (via substitution groups) by the
states found in the component schemas. An
actual state element is not valid. The use
of this abstract class simplifies the OVAL
schema by allowing individual states to
inherit the optional notes child element,
and the id and operator attributes from
the base StateType. Please refer to the
description of the StateType complex type
for more information.
An OVAL State is a
collection of one or more characteristics
pertaining to a specific object type. The
OVAL State is used by an OVAL Test to
determine if a unique set of items
identified on a system meet certain
characteristics.
The base type of every
state includes an optional notes element
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and two attributes. The notes section of a
state should be used to hold information
that might be helpful to someone examining
the technical aspects of the state. For
example, why certain values have been used
by the state, or maybe a link to where
further information can be found. Please
refer to the description of the NotesType
complex type for more information about
the notes element.
The required id attribute
uniquely identifies each state, and must
conform to the format specified by the
StateIdPattern simple type. The required
version attribute holds the current
version of the state. Versions are
integers, starting at 1 and incrementing
every time a state is modified. The
required operator attribute provides the
logical operator that binds the different
characteristics inside a state together.
The optional comment attribute provides a
short description of the state. The
optional deprecated attribute signifies
that an id is no longer to be used or
referenced but the information has been
kept around for historic
purposes.
When evaluating a
particular state against an object, one
should evaluate each individual entity
separately. The individual results are
then combined by the operator to produce
an overall result. This process holds true
even when there are multiple instances of
the same entity. Evaluate each instance
separately, taking the entity check
attribute into account, and then combine
everything using the
operator.
The VariablesType complex
type is a container for one or more
variable child elements. Each variable
element is a way to define one or more
values to be obtained at the time a
definition is
evaluated.
The variable element is
an abstract element that is meant to be
extended (via substitution groups) by the
different types of variables. An actual
variable element is not valid. The
different variable types describe
different sources for obtaining a value(s)
for the variable. There are currently
three types of variables; local, external,
and constant. Please refer to the
description of each one for more specific
information. The value(s) of a variable is
treated as if it were inserted where
referenced. One of the main benefits of
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variables is that they allow tests to
evaluate user-defined policy. For example,
an OVAL Test might check to see if a
password is at least a certain number of
characters long, but this number depends
upon the individual policy of the user. To
solve this, the test for password length
can be written to refer to a variable
element that defines the
length.
If a variable defines a
collection of values, any entity that
references the variable will evaluate to
true depending on the value of the
var_check attribute. For example, if an
entity 'size' with an operation of 'less
than' references a variable that returns
five different integers, and the var_check
attribute has a value of 'all', then the
'size' entity returns true only if the
actual size is less than each of the five
integers defined by the variable. If a
variable does not return any value, then
an error should be reported during OVAL
analysis.
The VariableType complex
type defines attributes associated with
each OVAL Variable. The required id
attribute uniquely identifies each
variable, and must conform to the format
specified by the VariableIDPattern simple
type. The required version attribute holds
the current version of the variable.
Versions are integers, starting at 1 and
incrementing every time a variable is
modified. The required comment attribute
provides a short description of the
variable. The optional deprecated
attribute signifies that an id is no
longer to be used or referenced but the
information has been kept around for
historic purposes.
The required datatype
attribute specifies the type of value
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being defined. The set of values
identified by a variable must comply with
the specified datatype, otherwise an error
should be reported. Please see the
DatatypeEnumeration for details about each
valid datatype. For example, if the
datatype of the variable is specified as
boolean then the value(s) returned by the
component / function should be "true",
"false", "1", or "0".
Note that the 'record'
datatype is not permitted on variables.
The notes section of a variable should be
used to hold information that might be
helpful to someone examining the technical
aspects of the variable. Please refer to
the description of the NotesType complex
type for more information about the notes
element.
Note that the 'record'
datatype is not permitted on
variables.
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The external_variable
element extends the VariableType and
defines a variable with some external
source. The actual value(s) for the
variable is not provided within the OVAL
file, but rather it is retrieved during
the evaluation of the OVAL Definition from
an external source. An unbounded set of
possible-value and possible_restriction
child elements can be specified that
together specify the list of all possible
values that an external source is allowed
to supply for the external variable. In
other words, the value assigned by an
external source must match one of the
possible_value or possible_restriction
elements specified. Each possible_value
element contains a single value that could
be assigned to the given external_variable
while each possible_restriction element
outlines a range of possible values. Note
that it is not necessary to declare a
variable's possible values, but the option
is available if desired. If no possible
child elements are specified, then the
valid values are only bound to the
specified datatype of the external
variable. Please refer to the description
of the PossibleValueType and
PossibleRestrictionType complex types for
more information.
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The PossibleValueType
complex type is used to outline a single
expected value of an external variable.
The required hint attribute gives a short
description of what the value means or
represents.
The
PossibleRestrictionType complex type
outlines a range of possible expected
value of an external variable. Each
possible_restriction element contains an
unbounded list of child restriction
elements that each specify a range that an
actual value may fall in. For example, a
restriction element may specify that a
value must be less than 10. When multiple
restriction elements are present, a valid
possible value's evaluation is based on
the operator attribute. The operator
attribute is set to AND by default. Other
valid operation values are explained in
the description of the OperatorEnumeration
simple type. One can think of the
possible_value and possible_restriction
elements as an OR'd list of possible
values, with the restriction elements as
using the selected operation to evaluate
its own list of value descriptions. Please
refer to the description of the
RestrictionType complex type for more
information. The required hint attribute
gives a short description of what the
value means or
represents.
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The RestrictionType
complex type outlines a restriction that
is placed on expected values for an
external variable. For example, a possible
value may be restricted to a integer less
than 10. Please refer to the
operationEnumeration simple type for a
description of the valid operations. The
required hint attribute gives a short
description of what the value means or
represents.
The constant_variable
element extends the VariableType and
defines a variable with a constant
value(s). Each constant_variable defines
either a single value or a collection of
values to be used throughout the
evaluation of the OVAL Definition File in
which it has been defined. Constant
variables cannot be over-ridden by an
external source. The actual value of a
constant variable is defined by the
required value child element. A collection
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of values can be specified by including
multiple instances of the value element.
Please refer to the description of the
ValueType complex type for more
information.
The ValueType complex
type holds the actual value of the
variable when dealing with a constant
variable. This value should be used by all
tests that reference this variable. The
value cannot be over-ridden by an external
source.
The local_variable
element extends the VariableType and
defines a variable with some local source.
The actual value(s) for the variable is
not provided in the OVAL Definition
document but rather it is retrieved during
the evaluation of the OVAL Definition.
Each local variable is defined by either a
single component or a complex function,
meaning that a value can be as simple as a
literal string or as complex as multiple
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registry keys concatenated together. Note
that if an individual component is used
and it returns a collection of values,
then there will be multiple values
associated with the local_variable. For
example, if an object_component is used
and it references a file object that
identifies a set of 5 files, then the
local variable would evaluate to a
collection of those 5 values. Please refer
to the description of the ComponentGroup
for more information.
Any value that is pulled
directly off the local system is defined
by the basic component element. For
example, the name of a user or the value
of a registry key. Please refer to the
definition of the ObjectComponentType for
more information. A value can also be
obtained from another variable. The
variable element identifies a variable id
to pull a value(s) from. Please refer to
the definition of the
VariableComponentType for more
information. Literal values can also be
specified.
The LiteralComponentType
complex type defines a literal value to be
used as a component. The optional datatype
attribute defines the type of data
expected. The default datatype is
'string'.
- The
'record' datatype is prohibited on
variables.
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The ObjectComponentType
complex type defines a specific value or
set of values on the local system to
obtain.
The required object_ref
attribute provides a reference to an
existing OVAL Object declaration. The
referenced OVAL Object specifies a set of
OVAL Items to collect. Note that an OVAL
Object might identify 0, 1, or many OVAL
Items on a system. If no items are found
on the system then an error should be
reported when determining the value of an
ObjectComponentType. If 1 or more OVAL
Items are found then each OVAL Item will
be considered and the ObjectComponentType
may have one or more
values.
The required item_field
attribute specifies the name of the entity
whose value will be retrieved from each
OVAL Item collected by the referenced OVAL
Object. For example, if the object_ref
references a win-def:file_object, the
item_field may specify the 'version'
entity as the field to use as the value of
the ObjectComponentType. Note that an OVAL
Item may have 0, 1, or many entities whose
name matches the specified item_field
value. If an entity is not found with a
name that matches the value of the
item_field an error should be reported
when determining the value of an
ObjectComponentType. If 1 or more matching
entities are found in a single OVAL Item
the value of the ObjectComponentType is
the list of the values from each of the
matching entities.
The optional record_field
attribute specifies the name of a field in
a record entity in an OVAL Item. The
record_field attribute allows the value of
a specific field to be retrieved from an
entity with a datatype of 'record'. If a
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field with a matching name attribute value
is not found in the referenced OVAL Item
entity an error should be reported when
determining the value of the
ObjectComponentType.
The VariableComponentType
complex type defines a specific value
obtained by looking at the value of
another OVAL Variable. The required
var_ref attribute provides a reference to
the variable. One must make sure that the
variable reference does not point to the
parent variable that uses this component
to avoid a race
condition.
Complex functions have
been defined that help determine how to
manipulate specific values. These
functions can be nested together to form
complex statements. Each function is
designed to work on a specific type of
data. If the data being worked on is not
of the correct type, a cast should be
attempted before reporting an error. For
example, if a concat function includes a
registry component that returns an
integer, then the integer should be cast
as a string in order to work with the
concat function. Note that if the
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operation being applied to the variable by
the calling entity is "pattern match",
then all the functions are performed
before the regular expression is
evaluated. In short, the variable would
produce a value as normal and then any
pattern match operation would be
performed. It is also important to note
that when using these functions with
sub-components that return a collection of
values that the operation will be
performed on the Cartesian product of the
components and the result is also a
collection of values. For example, assume
a local_variable specifies the arithmetic
function with an arithmetic_operation of
"add" and has two sub-components under
this function: the first component returns
"1" and "2", and the second component
returns "3" and "4" and "5". The
local_variable element would be evaluated
to have a collection of six values: 1+3,
1+4, 1+5, 2+3, 2+4, and 2+5. Please refer
to the description of a specific function
for more details about
it.
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The arithmetic function
takes two or more integer or float
components and performs a basic
mathematical function on them. The result
of this function is a single integer or
float unless one of the components returns
a collection of values. In this case the
specified arithmetic function would be
performed multiple times and the end
result would also be a collection of
values for the local variable. For example
assume a local_variable specifies the
arithmetic function with an
arithmetic_operation of "add" and has two
sub-components under this function: the
first component returns "1" and "2", and
the second component returns "3" and "4"
and "5". The local_variable element would
be evaluated to be a collection of six
values: 1+3, 1+4, 1+5, 2+3, 2+4, and
2+5.
Note that if both an
integer and float components are used then
the result is a float.
A literal_component used by an
arithmetic function must have a
datatype of float or
int.
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The variable referenced by the
arithmetic function must have a
datatype of float or
int.
The begin function takes
a single string component and defines a
character (or string) that the component
string should start with. The character
attribute defines the specific character
(or string). The character (or string) is
only added to the component string if the
component string does not already start
with the specified character (or string).
If the component string does not start
with the specified character (or string)
the entire character (or string) will be
prepended to the component
string..
A literal_component used by the
begin function must have a datatype
of string.
The variable referenced by the
begin function must have a datatype
of string.
The concat function takes
two or more components and concatenates
them together to form a single string. The
first component makes up the beginning of
the resulting string and any following
components are added to the end it. If one
of the components returns multiple values
then the concat function would be
performed multiple times and the end
result would be a collection of values for
the local variable. For example assume a
local variable has two sub-components: a
basic component element returns the values
"abc" and "def", and a literal component
element that has a value of "xyz". The
local_variable element would evaluate to a
collection of two values, "abcxyz" and
"defxyz". If one of the components does
not exist, then the result of the concat
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operation should be does not
exist.
Below is a chart
that specifies how to classify the flag
status of a variable using the concat
function during evaluation when multiple
components are supplied. Both the object
and variable component are indirectly
associated with collected objects in a
system characteristics file. These
objects could have been completely
collected from the system, or there
might have been some type of error that
led to the object not being collected,
or maybe only a part of the object set
was collected. This flag status is
important as OVAL Objects or OVAL States
that are working with a variable
(through the var_ref attribute on an
entity) can use this information to
report more accurate results. For
example, an OVAL Test with a check
attribute of 'at least one' that
specifies an object with a variable
reference, might be able to produce a
valid result based on an incomplete
object set as long as one of the objects
in the set is
true.
|| num of components with flag ||
|| || resulting flag is
|| E | C | I | DNE | NC | NA ||
----||-----------------------------------||------------------
|| 1+ | 0+ | 0+ | 0+ | 0+ | 0+ || Error
|| 0 | 1+ | 0 | 0 | 0 | 0 || Complete
|| 0 | 0+ | 1+ | 0 | 0 | 0 || Incomplete
|| 0 | 0+ | 0+ | 1+ | 0 | 0 || Does Not Exist
|| 0 | 0+ | 0+ | 0+ | 1+ | 0 || Not Collected
|| 0 | 0+ | 0+ | 0+ | 0+ | 1+ || Not Applicable
----||-----------------------------------||------------------
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A literal_component used by the
concat function must have a datatype
of string.
The variable referenced by the
concat function must have a datatype
of string.
The end function takes a
single string component and defines a
character (or string) that the component
string should end with. The character
attribute defines the specific character
(or string). The character (or string) is
only added to the component string if the
component string does not already end with
the specified character (or string). If
the desired end character is a string,
then the entire end string must exist at
the end if the component string. If the
entire end string is not present then the
entire end string is appended to the
component string.
A literal_component used by the end
function must have a datatype of
string.
The variable referenced by the end
function must have a datatype of
string.
The escape_regex function
takes a single string component and
escapes all of the regular expression
characters. If the string sub-component
contains multiple values, then the
escape_regex function will be applied to
each individual value and return a
multiple-valued result. For example, the
string '(\.test_string*)?' will evaluate
to '\(\\\.test_string\*\)\?'. The purpose
for this is that many times, a component
used in pattern match needs to be treated
as a literal string and not a regular
expression. For example, assume a basic
component element that identifies a file
path that is held in the Windows registry.
This path is a string that might contain
regular expression characters. These
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characters are likely not intended to be
treated as regular expression characters
and need to be escaped. This function
allows a definition writer to mark convert
the values of components to regular
expression format.
Note that when using
regular expressions, OVAL supports a
common subset of the regular expression
character classes, operations, expressions
and other lexical tokens defined within
Perl 5's regular expression specification.
The set of Perl metacharacters which must
be escaped by this function is as follows,
enclosed by single quotes:
'^$\.[](){}*+?|'. For more information on
the supported regular expression syntax in
OVAL see:
http://oval.mitre.org/language/
about/re_support_5.6.html.
A literal_component used by the
escape_regex function must have a
datatype of string.
The variable referenced by the
escape_regex function must have a
datatype of string.
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The split function takes
a single string component and turns it
into a collection of values based on a
delimiter string. For example, assume that
a basic component element returns the
value "a-b-c-d" to the split function with
the delimiter set to "-". The
local_variable element would be evaluated
to have four values "a", "b", "c", and
"d". If the basic component returns a
value that begins, or ends, with a
delimiter, the local_variable element
would contain empty string values at the
beginning, or end, of the collection of
values returned for that string component.
For example, if the delimiter is "-", and
the basic component element returns the
value "-a-a-", the local_variable element
would evaluate to a collection of four
values "", "a", "a", and "". Likewise, if
the basic component element returns a
value that contains adjacent delimiters
such as "---", the local_variable element
would evaluate to a collection of four
values "", "", "", and "". Lastly, if the
basic component element used by the split
function returnsa collection of values,
then the split function is performed
multiple times, and all of the results,
from each of the split functions, are
returned.
A literal_component used by the
split function must have a datatype
of string.
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The variable referenced by the
split function must have a datatype
of string.
The substring function
takes a single string component and
produces a single value that contains a
portion of the original string. The
substring_start attribute defines the
starting position in the original string.
To include the first character of the
string, the start position would be 1. A
value less than 1 also means that the
start position would be 1. If the
substring_start attribute has value
greater than the length of the original
string an error should be reported. The
substring_length attribute defines how
many characters after, and including, the
starting character to include. A
substring_length value greater than the
actual length of the string, or a negative
value, means to include all of the
characters after the starting character.
For example, assume a basic component
element that returns the value "abcdefg"
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with a substring_start value of 3 and a
substring_length value of 2. The
local_variable element would evaluate to
have a single value of "cd". If the string
component used by the substring function
returns a collection of values, then the
substring operation is performed multiple
times and results in a collection of
values for the
component.
A literal_component used by the
substring function must have a
datatype of string.
The variable referenced by the
substring function must have a
datatype of string.
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The time_difference
function calculates the difference in
seconds between date-time values. If one
component is specified, the values of that
component are subtracted from the current
time (UTC). The current time is the time
at which the function is evaluated. If two
components are specified, the value of the
second component is subtracted from the
value of the first component. If the
component(s) contain a collection of
values, the operation is performed
multiple times on the Cartesian product of
the component(s) and the result is also a
collection of time difference values. For
example, assume a local_variable specifies
the time_difference function and has two
sub-components under this function: the
first component returns "04/02/2009" and
"04/03/2009", and the second component
returns "02/02/2005" and "02/03/2005" and
"02/04/2005". The local_variable element
would evaluate to a collection of six
values: (ToSeconds("04/02/2009") -
ToSeconds("02/02/2005")),
(ToSeconds("04/02/2009") -
ToSeconds("02/03/2005")),
(ToSeconds("04/02/2009") -
ToSeconds("02/04/2005")),
(ToSeconds("04/03/2009") -
ToSeconds("02/02/2005")),
(ToSeconds("04/03/2009") -
ToSeconds("02/03/2005")), and
(ToSeconds("04/03/2009") -
ToSeconds("02/04/2005")).
The date-time format of
each component is determined by the two
format attributes. The format1 attribute
applies to the first component, and the
format2 attribute applies to the second
component. Valid values for the attributes
are 'win_filetime', 'seconds_since_epoch',
'day_month_year', 'year_month_day', and
'month_day_year'. Please see the
DateTimeFormatEnumeration for more
information about each of these values. If
an input value is not understood, the
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result is an error. If only one input is
specified, specify the format with the
format2 attribute, as the first input is
considered to be the implied 'current
time' input.
Note that the datatype
associated with the components should be
'string' or 'int' depending on which date
time format is specified. The result of
this function though is always an
integer.
A literal_component used by the
time_difference function must have a
datatype of string or
int.
The variable referenced by the
time_difference function must have a
datatype of string or
int.
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The regex_capture
function captures a single substring from
a single string component. If the string
sub-component contains multiple values,
then the regex_capture function will
extract a substring from each value. The
'pattern' attribute provides a regular
expression that should contain a single
subexpression (using parentheses). For
example, the pattern ^abc(.*)xyz$ would
capture a substring from each of the
string component's values if the value
starts with abc and ends with xyz. In this
case the subexpression would be all the
characters that exist in between the abc
and the xyz. Note that subexpressions
match the longest possible
substrings.
If the regular expression
contains multiple capturing sub-patterns,
only the first capture is used. If there
are no capturing sub-patterns, the result
for each target string must be the empty
string. Otherwise, if the regular
expression could match the target string
in more than one place, only the first
match (and its first capture) is used. If
no matches are found in a target string,
the result for that target must be the
empty string.
Note that a quantified
capturing sub-pattern does not produce
multiple substrings. Standard regular
expression semantics are such that if a
capturing sub-pattern is required to match
multiple times in order for the overall
regular expression to match, the capture
produced is the last substring to have
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matched the
sub-pattern.
Note that when using
regular expressions, OVAL supports a
common subset of the regular expression
character classes, operations, expressions
and other lexical tokens defined within
Perl 5's regular expression specification.
If any of the Perl metacharacters are to
be used literally, then they must be
escaped. The set of metacharacters which
must be escaped for this purpose is as
follows, enclosed by single quotes:
'^$\.[](){}*+?|'. For more information on
the supported regular expression syntax in
OVAL see:
http://oval.mitre.org/language/
about/re_support_5.6.html.
A literal_component used by the
regex_capture function must have a
datatype of string.
The variable referenced by the
regex_capture function must have a
datatype of string.
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The unique function takes
one or more components and removes any
duplicate value from the set of
components. All components used in the
unique function will be treated as
strings. For example, assume that three
components exist, one that contains a
string value of 'foo', and two of which
both resolve to the string value 'bar'.
Applying the unique function to these
three components resolves to a
local_variable with two string values,
'foo' and 'bar'. Additionally, if any of
the components referenced by the unique
function evaluate to a collection of
values, then those values are used in the
unique calculation. For example, assume
that there are two components, one of
which resolves to a single string value,
'foo', the other of which resolves to two
string values, 'foo' and 'bar'. If the
unique function is used to remove
duplicates from these two components, the
function will resolve to a local_variable
that is a collection of two string values,
'foo' and 'bar'.
The count function takes
one or more components and returns the
count of all of the values represented by
the components. For example, assume that
two variables exist, each with a single
value. By applying the count function
against two variable components that
resolve to the two variables, the
resulting local_variable would have a
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value of '2'. Additionally, if any of the
components referenced by the count
function evaluate to a collection of
values, then those values are used in the
count calculation. For example, assume
that there are two components, one of
which resolves to a single value, the
other of which resolves to two values. If
the count function is used to provide a
count of these two components, the
function will resolve to a local_variable
with the values '3'.
The glob_to_regex
function takes a single string component
representing shell glob pattern and
produces a single value that corresponds
to result of a conversion of the original
glob pattern into Perl 5's regular
expression pattern. The glob_noescape
attribute defines the way how the
backslash ('\') character should be
interpreted. It defaults to 'false'
meaning backslash should be interpreted as
an escape character (backslash is allowed
to be used as an escape character). If the
glob_noescape attribute would be set to
'true' it instructs the glob_to_regex
function to interpret the backslash ('\')
character as a literal, rather than as an
escape character (backslash is *not*
allowed to be used as an escape
character). Refer to table with examples
below to see the difference how a
different boolean value of the
'glob_noescape' attribute will impact the
output form of the resulting Perl 5's
regular expression produced by
glob_to_regex
function.
Please note the
glob_to_regex function will fail to
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perform the conversion and return an error
when the provided string argument (to
represent glob pattern) does not represent
a syntactically correct glob pattern. For
example given the 'a*b?[' as the argument
to be converted, glob_to_regex would
return an error since there's missing the
corresponding closing bracket in the
provided glob pattern
argument.
Also, it is necessary to
mention that the glob_to_regex function
respects the default behaviour for the
input glob pattern and output Perl 5's
regular expression spaces. Namely this
means that:
- glob_to_regex will
respect the UNIX glob behavior when
processing forward slashes, forward slash
should be treated as a path separator and
* or ? shall not match
it,
- glob_to_regex will
rule out matches having special meaning
(for example '.' as a representation of
the current working directory or '..' as a
representation of the parent directory of
the current working
directory,
- glob_to_regex will
rule out files or folders starting with
'.' character (e.g. dotfiles) unless the
respective glob pattern part itself starts
with the '.'
character,
- glob_to_regex will not
perform case-sensitivity transformation
(alphabetical characters will be copied
from input glob pattern space to output
Perl 5's regular expression pattern space
intact). It is kept as a responsibility of
the OVAL content author to provide input
glob pattern argument in such case so the
resulting Perl 5's regular expression
pattern will match the expected pathname
entries according to the case of
preference,
- glob_to_regex will not
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perform any possible brace expansion.
Therefore glob patterns like
'{pat,pat,pat}' would be converted into
Perl 5's regular expression syntax in the
original un-expanded form (kept for any
potential subsequent expansion to be
performed by Perl 5's regular expression
engine in the moment of the use of that
resulting regular
expression),
- glob_to_regex will not
perform tilde ('~') character substitution
to user name home directory pathname. The
('~') character will be passed to Perl 5's
regular expression engine intact. If user
name home directory pathname glob pattern
behaviour is expected, the pathname of the
user name home directory needs to be
specified in the original input glob
pattern already,
- glob_to_regex function
will not perform any custom changes wrt to
the ordering of items (perform any
additional sorting of set of pathnames
represented by the provided glob pattern
argument).
Below are some
examples that outline how the
glob_noescape attribute value affects
the output form of the produced Perl
regular expression. The far left column
identifies the shell glob pattern
provided as the input string component
to the glob_to_regex function. The
middle column specifies the two possible
different boolean values of the
'glob_noescape' attribute that can be
used. Finally the last column depicts
how the output produced by the
glob_to_regex function - the resulting
Perl regular expression would look
like.
|| ||
input || glob_ || corresponding
shell || noescape ||
glob || attribute || Perl
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pattern || value || Regular
|| || Expression
------------------||-----------||-------------------------------
'\*' || false || ^\*$
||-----------||-------------------------------
'\*' || true || ^\\[^/]*$
------------------||-----------||-------------------------------
'\?' || false || ^\?$
||-----------||-------------------------------
'\?' || true || ^\\[^./]$
------------------||-----------||-------------------------------
'\[hello\]' || false || ^\[hello\]$
||-----------||-------------------------------
'\[hello\]' || true || ^\\[hello\\]$
------------------||-----------||-------------------------------
'/root/*' || false || ^/root/(?=[^.])[^/]*$
||-----------||-------------------------------
'/root/.*' || false || ^/root/\.[^/]*$
||-----------||-------------------------------
'/root/x*' || false || ^/root/x[^/]*$
||-----------||-------------------------------
'/root/?' || false || ^/root/[^./]$
||-----------||-------------------------------
'/root/.?' || false || ^/root/\.[^/]$
||-----------||-------------------------------
'/root/x?' || false || ^/root/x[^/]$
------------------||-----------||-------------------------------
'list.?' || false || ^list\.[^/]$
||-----------||-------------------------------
'list.?' || true || ^list\.[^/]$
||-----------||-------------------------------
'project.*' || false || ^project\.[^/]*$
||-----------||-------------------------------
'project.*' || true || ^project\.[^/]*$
||-----------||-------------------------------
'*old' || false || ^(?=[^.])[^/]*old$
||-----------||-------------------------------
'*old' || true || ^(?=[^.])[^/]*old$
||-----------||-------------------------------
'type*.[ch]' || false || ^type[^/]*\.[ch]$
||-----------||-------------------------------
'type*.[ch]' || true || ^type[^/]*\.[ch]$
||-----------||-------------------------------
'*.*' || false || ^(?=[^.])[^/]*\.[^/]*$
||-----------||-------------------------------
'*.*' || true || ^(?=[^.])[^/]*\.[^/]*$
||-----------||-------------------------------
'*' || false || ^(?=[^.])[^/]*$
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||-----------||-------------------------------
'*' || true || ^(?=[^.])[^/]*$
||-----------||-------------------------------
'?' || false || ^[^./]$
||-----------||-------------------------------
'?' || true || ^[^./]$
||-----------||-------------------------------
'\*' || false || ^\*$
||-----------||-------------------------------
'\*' || true || ^\\[^/]*$
||-----------||-------------------------------
'\?' || false || ^\?$
||-----------||-------------------------------
'\?' || true || ^\\[^./]$
||-----------||-------------------------------
'x[[:digit:]]\*' || false || ^x[[:digit:]]\*$
||-----------||-------------------------------
'x[[:digit:]]\*' || true || ^x[[:digit:]]\\[^/]*$
||-----------||-------------------------------
'' || false || ^$
||-----------||-------------------------------
'' || true || ^$
||-----------||-------------------------------
'~/files/*.txt' || false || ^~/files/(?=[^.])[^/]*\.txt$
||-----------||-------------------------------
'~/files/*.txt' || true || ^~/files/(?=[^.])[^/]*\.txt$
||-----------||-------------------------------
'\' || false || ^\\$
||-----------||-------------------------------
'\' || true || ^\\$
||-----------||-------------------------------
'[ab' || false || INVALID
||-----------||-------------------------------
'[ab' || true || INVALID
||-----------||-------------------------------
'.*.conf' || false || ^\.[^/]*\.conf$
||-----------||-------------------------------
'.*.conf' || true || ^\.[^/]*\.conf$
||-----------||-------------------------------
'docs/?b' || false || ^docs/[^./]b$
||-----------||-------------------------------
'docs/?b' || true || ^docs/[^./]b$
||-----------||-------------------------------
'xy/??z' || false || ^xy/[^./][^/]z$
||-----------||-------------------------------
'xy/??z' || true || ^xy/[^./][^/]z$
----------------------------------------------------------------
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A literal_component used by the
glob_to_regex function must have a
datatype of string.
The variable referenced by the
glob_to_regex function must have a
datatype of string.
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The ArithmeticEnumeration
simple type defines basic arithmetic
operations. Currently add and multiply are
defined.
The
DateTimeFormatEnumeration simple type
defines the different date-time formats
that are understood by OVAL. Note that in
some cases there are a few different
possibilities within a given format. Each
of these possibilities is unique though
and can be distinguished from each other.
The different formats are used to clarify
the higher level structure of the
date-time string being
used.
The year_month_day
value specifies date-time strings that
follow the formats: 'yyyymmdd',
'yyyymmddThhmmss', 'yyyy/mm/dd
hh:mm:ss', 'yyyy/mm/dd', 'yyyy-mm-dd
hh:mm:ss', or
'yyyy-mm-dd'
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The month_day_year
value specifies date-time strings that
follow the formats: 'mm/dd/yyyy
hh:mm:ss', 'mm/dd/yyyy', 'mm-dd-yyyy
hh:mm:ss', 'mm-dd-yyyy', 'NameOfMonth,
dd yyyy hh:mm:ss' or 'NameOfMonth, dd
yyyy', 'AbreviatedNameOfMonth, dd yyyy
hh:mm:ss', or 'AbreviatedNameOfMonth,
dd yyyy'
The day_month_year
value specifies date-time strings that
follow the formats: 'dd/mm/yyyy
hh:mm:ss', 'dd/mm/yyyy', 'dd-mm-yyyy
hh:mm:ss', or
'dd-mm-yyyy'
The win_filetime
value specifies date-time strings that
follow the windows file time
format.
The
seconds_since_epoch value specifies
date-time values that represent the
time in seconds since the UNIX epoch.
The Unix epoch is the time 00:00:00
UTC on January 1,
1970.
The cim_datetime
model is used by WMI and its value
specifies date-time strings that
follow the format:
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'yyyymmddHHMMSS.mmmmmmsUUU', and
alternatively 'yyyy-mm-dd
HH:MM:SS:mmm' only when used in WMI
Query Language
queries.
The
FilterActionEnumeration simple type
defines the different options for
filtering sets of
items.
The exclude value
specifies that all items that match
the filter shall be excluded from set
that the filter is applied
to.
The include value
specifies that only items that match
the filter shall be included in the
set that the filter is applied
to.
The
SetOperatorEnumeration simple type defines
acceptable set operations. Set operations
are used to take multiple different sets
of objects within OVAL and merge them into
a single unique set. The different
operators that guide this merge are
defined below. For each operator, if only
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a single object has been supplied, then
the resulting set is simply that complete
object.
Below are some
tables that outline how different flags
are combined with a given set_operator
to return a new flag. These tables are
needed when computing the flag for
collected objects that represent object
sets in an OVAL Definition. The top row
identifies the flag associated with the
first set or object reference. The left
column identifies the flag associated
with the second set or object reference.
The matrix inside the table represent
the resulting flag when the given
set_operator is applied. (E=error,
C=complete, I=incomplete, DNE=does not
exist, NC=not collected, NA=not
applicable)
|| ||
set_operator is || obj 1 flag ||
union || ||
|| E | C | I | DNE | NC | NA ||
-----------------||-----------------------------------||
E || E | E | E | E | E | E ||
obj C || E | C | I | C | I | C ||
2 I || E | I | I | I | I | I ||
flag DNE || E | C | I | DNE | I | DNE ||
NC || E | I | I | I | NC | NC ||
NA || E | C | I | DNE | NC | NA ||
-----------------||-----------------------------------||
|| ||
set_operator is || obj 1 flag ||
intersection || ||
|| E | C | I | DNE | NC | NA ||
-----------------||-----------------------------------||
E || E | E | E | DNE | E | E ||
obj C || E | C | I | DNE | NC | C ||
2 I || E | I | I | DNE | NC | I ||
flag DNE || DNE | DNE | DNE | DNE | DNE | DNE ||
NC || E | NC | NC | DNE | NC | NC ||
NA || E | C | I | DNE | NC | NA ||
-----------------||-----------------------------------||
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|| ||
set_operator is || obj 1 flag ||
complement || ||
|| E | C | I | DNE | NC | NA ||
-----------------||-----------------------------------||
E || E | E | E | DNE | E | E ||
obj C || E | C | I | DNE | NC | E ||
2 I || E | E | E | DNE | NC | E ||
flag DNE || E | C | I | DNE | NC | E ||
NC || E | NC | NC | DNE | NC | E ||
NA || E | E | E | E | E | E ||
-----------------||-----------------------------------||
The complement
operator is defined in OVAL as a
relative complement. The resulting
unique set contains everything that
belongs to the first declared set that
is not part of the second declared
set. If A and B are sets (with A being
the first declared set), then the
relative complement is the set of
elements in A, but not in B, with the
duplicates
removed.
The intersection of
two sets in OVAL results in a unique
set that contains everything that
belongs to both sets in the
collection, but nothing else. If A and
B are sets, then the intersection of A
and B contains all the elements of A
that also belong to B, but no other
elements, with the duplicates
removed.
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The union of two sets
in OVAL results in a unique set that
contains everything that belongs to
either of the original sets. If A and
B are sets, then the union of A and B
contains all the elements of A and all
elements of B, with the duplicates
removed.
The EntityAttributeGroup
is a collection of attributes that are
common to all entities. This group defines
these attributes and their default values.
Individual entities may limit allowed
values for these attributes, but all
entities will support these
attributes.
- a var_ref has
been supplied for the entity so no
value should be
provided
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- inconsistent datatype between the
variable and an associated
var_ref
-
a var_ref has been supplied for the
entity so a var_check should also be
provided
-
a var_check has been supplied for
the
entity so a var_ref must also be
provided
-
a var_ref has been supplied for the
entity so a var_check should also be
provided
-
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a var_check has been supplied for
the
entity so a var_ref must also be
provided
-
The use of '' for the
operation attribute of the
entity is not valid given the lack
of a declared datatype (hence a
default datatype of
string).
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of binary.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of boolean.
-
The use of '' for the
operation attribute of the
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entity is not valid given a datatype
of evr_string.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of debian_evr_string.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of fileset_revision.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of float.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of ios_version.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of int.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of ipv4_address.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of ipv6_address.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of string.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of version.
-
The use of '' for the
operation attribute of the
entity is not valid given a datatype
of record.
-
The use of var_ref is prohibited
when the datatype is
'record'.
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-
The datatype for the entity is 'int'
but the value is not an
integer.
The optional datatype
attribute specifies how the given
operation should be applied to the data.
Since we are dealing with XML everything
is technically a string, but often the
value is meant to represent some other
datatype and this affects the way an
operation is performed. For example,
with the statement 'is 123 less than
98'. If the data is treated as integers
the answer is no, but if the data is
treated as strings, then the answer is
yes. Specifying a datatype defines how
the less than operation should be
performed. Another way of thinking of
things is that the datatype attribute
specifies how the data should be cast
before performing the operation (note
that the default datatype is 'string').
In the previous example, if the datatype
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is set to int, then '123' and '98'
should be cast as integers. Another
example is applying the 'equals'
operation to '1.0.0.0' and '1.0'. With
datatype 'string' they are not equal,
with datatype 'version' they are. Note
that there are certain cases where a
cast from one datatype to another is not
possible. If a cast cannot be made,
(trying to cast 'abc' to an integer)
then an error should be reported. For
example, if the datatype is set to
'integer' and the value is the empty
string. There is no way to cast the
empty string (or NULL) to an integer,
and in cases like this an error should
be reported.
The optional operation
attribute determines how the individual
entities should be evaluated (the
default operation is
'equals').
The optional mask
attribute is used to identify values
that have been hidden for sensitivity
concerns. This is used by the Result
document which uses the System
Characteristics schema to format the
information found on a specific system.
When the mask attribute is set to 'true'
on an OVAL Entity or an OVAL Field, the
corresponding collected value of that
OVAL Entity or OVAL Field MUST NOT be
present in the "results" section of the
OVAL Results document; the
"oval_definitions" section must not be
altered and must be an exact copy of the
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definitions evaluated. Values MUST NOT
be masked in OVAL System Characteristics
documents that are not contained within
an OVAL Results document. It is possible
for masking conflicts to occur where one
entity has mask set to true and another
entity has mask set to false. A conflict
will occur when the mask attribute is
set differently on an OVAL Object and
matching OVAL State or when more than
one OVAL Objects identify the same OVAL
Item(s). When such a conflict occurs the
result is always to mask the
entity.
The optional var_ref
attribute refers the value of the
element to a variable element. When
supplied, the value(s) associated with
the OVAL Variable should be used as the
value(s) of the element. If there is an
error computing the value of the
variable, then that error should be
passed up to the element referencing it.
If the variable being referenced does
not have a value (for example, if the
variable pertains to the size of a file,
but the file does not exist) then one of
two results are possible. If the element
is part of an object declaration, then
the object element referencing it is
considered to not exist. If the element
is part of a state declaration, then the
state element referencing it will
evaluate to error.
The optional var_check
attribute specifies how data collection
or state evaluation should proceed when
an element uses a var_ref attribute, and
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the associated variable defines more
than one value. For example, if an
object entity 'filename' with an
operation of 'not equal' references a
variable that returns five different
values, and the var_check attribute has
a value of 'all', then an actual file on
the system matches only if the actual
filename does not equal any of the
variable values. As another example, if
a state entity 'size' with an operation
of 'less than' references a variable
that has five different integer values,
and the var_check attribute has a value
of 'all', then the 'size' state entity
evaluates to true only if the
corresponding 'size' item entity is less
than each of the five integers defined
by the variable. If a variable does not
have any value value when referenced by
an OVAL Object the object should be
considered to not exist. If a variable
does not have any value when referenced
by an OVAL State an error should be
reported during OVAL analysis. When an
OVAL State uses a var_ref, if both the
state entity and a corresponding item
entity are collections of values, the
var_check is applied to each value of
the item entity individually, and all
must evaluate to true for the state
entity to evaluate to true. In this
condition, there is no value of
var_check which enables an element-wise
comparison, and so there is no way to
determine whether the two entities are
truly 'equal' in that sense. If var_ref
is present but var_check is not, the
element should be processed as if
var_check has the value
"all".
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The EntitySimpleBaseType
complex type is an abstract type that
defines the default attributes associated
with every simple entity. Entities can be
found in both OVAL Objects and OVAL States
and represent the individual properties
associated with items found on a system.
An example of a single entity would be the
path of a file. Another example would be
the version of the
file.
The EntityComplexBaseType
complex type is an abstract type that
defines the default attributes associated
with every complex entity. Entities can be
found in both OVAL Objects and OVAL States
and represent the individual properties
associated with items found on a system.
An example of a single entity would be the
path of a file. Another example would be
the version of the
file.
The
EntityObjectIPAddressType type is extended
by the entities of an individual OVAL
Object. This type provides uniformity to
each object entity by including the
attributes found in the
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EntitySimpleBaseType. This specific type
describes any IPv4/IPv6 address or address
prefix.
The
EntityObjectIPAddressStringType type is
extended by the entities of an individual
OVAL Object. This type provides uniformity
to each object entity by including the
attributes found in the
EntitySimpleBaseType. This specific type
describes any IPv4/IPv6 address, address
prefix, or its string
representation.
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The
EntityObjectAnySimpleType type is extended
by the entities of an individual OVAL
Object. This type provides uniformity to
each object entity by including the
attributes found in the
EntitySimpleBaseType. This specific type
describes any simple
data.
The EntityBinaryType type
is extended by the entities of an
individual OVAL Object. This type provides
uniformity to each object entity by
including the attributes found in the
EntitySimpleBaseType. This specific type
describes simple binary data. The empty
string is also allowed when using a
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variable reference with an
element.
The EntityBoolType type
is extended by the entities of an
individual OVAL Object. This type provides
uniformity to each object entity by
including the attributes found in the
EntitySimpleBaseType. This specific type
describes simple boolean data. The empty
string is also allowed when using a
variable reference with an
element.
The EntityObjectFloatType
type is extended by the entities of an
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individual OVAL Object. This type provides
uniformity to each object entity by
including the attributes found in the
EntitySimpleBaseType. This specific type
describes simple float data. The empty
string is also allowed when using a
variable reference with an
element.
The EntityIntType type is
extended by the entities of an individual
OVAL Object. This type provides uniformity
to each object entity by including the
attributes found in the
EntitySimpleBaseType. This specific type
describes simple integer data. The empty
string is also allowed when using a
variable reference with an
element.
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The EntityStringType type
is extended by the entities of an
individual OVAL Object. This type provides
uniformity to each object entity by
including the attributes found in the
EntitySimpleBaseType. This specific type
describes simple string
data.
The
EntityObjectVersionType type is extended
by the entities of an individual OVAL
State. This type provides uniformity to
each state entity by including the
attributes found in the
EntityStateSimpleBaseType. This specific
type describes simple version
data.
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The
EntityObjectRecordType defines an entity
that consists of a number of uniquely
named fields. This structure is used for
representing a record from a database
query and other similar structures where
multiple related fields must be
represented at once. Note that for all
entities of this type, the only allowed
datatype is 'record' and the only allowed
operation is 'equals'. During analysis of
a system characteristics item, each field
is analyzed and then the overall result
for elements of this type is computed by
logically anding the results for each
field and then applying the entity_check
attribute.
Note the datatype
attribute must be set to
'record'.
Note the operation
attribute must be set to
'equals'.
Note the var_ref
attribute is not permitted and the
var_check attribute does not
apply.
Note that when the mask
attribute is set to 'true', all child
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field elements must be masked regardless
of the child field's mask attribute
value.
The EntityObjectFieldType
defines an element with simple content
that represents a named field in a record
that may contain any number of named
fields. The EntityObjectFieldType is much
like all other entities with one
significant difference, the
EntityObjectFieldType has a name
attribute
The required name
attribute specifies a unique name for the
field. Field names are lowercase and must
be unique within a given parent record
element. When analyzing system
characteristics an error should be
reported for the result of a field that is
present in the OVAL State, but not found
in the system characteristics
Item.
The optional entity_check
attribute specifies how to handle multiple
record fields with the same name in the
OVAL Systems Characteristics file. For
example, while collecting group
information where one field is the
represents the users that are members of
the group. It is very likely that there
will be multiple fields with a name of
'user' associated with the group. If the
OVAL State defines the value of the field
with name equal 'user' to equal 'Fred',
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then the entity_check attribute determines
if all values for field entities must be
equal to 'Fred', or at least one value
must be equal to 'Fred',
etc.
Note that when the mask
attribute is set to 'true' on a field's
parent element the field must be masked
regardless of the field's mask attribute
value.
A string restricted
to disallow upper case
characters.
The
EntityStateSimpleBaseType complex type is
an abstract type that extends the
EntitySimpleBaseType and is used by some
entities within an OVAL
State.
The optional
check_existence attribute specifies how to
interpret the status of corresponding item
entities when performing an item-state
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comparison. The default value for this
attribute is 'at_least_one_exists'
indicating that by default an item
comparison may evaluate to true only if at
least one corresponding item entity has a
status of 'exists'. For example, if a
value of 'none_exist' is given, then the
comparison can evaluate to true only if
there are one or more corresponding item
entities, each with a status of 'does not
exist'.
The optional entity_check
attribute specifies how to handle multiple
item entities with the same name in the
OVAL Systems Characteristics file. For
example, suppose we are dealing with a
Group Test and an entity in the state is
related to the user. It is very likely
that when the information about the group
is collected off of the system (and
represented in the OVAL System
Characteristics file) that there will be
multiple users associated with the group
(i.e. multiple 'user' item entities
associated with the same 'user' state
entity). If the OVAL State defines the
value of the user entity to equal 'Fred',
then the entity_check attribute determines
if all values for 'user' item entities
must be equal to 'Fred', or at least one
value must be equal to 'Fred', etc. Note
that with the exception of the
'none_satisfy' check value, the
entity_check attribute can only affect the
result of the test if the corresponding
OVAL Item allows more than one occurrence
of the entity (e.g. 'maxOccurs' is some
value greater than
one).
The entity_check and
var_check attributes are considered
together when evaluating a single state
entity. When a variable identifies more
than one value and multiple item entities
with the same name exist, for a single
state entity, a many-to-many comparison
must be conducted. In this situation,
there are many values for the state entity
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that must be compared to many item
entities. Each item entity is compared to
the state entity. For each item entity, an
interim result is calculated by using the
var_check attribute to combine the result
of comparing each variable value with a
single system value. Then these interim
results are combined for each system value
using the entity_check
attribute.
The
EntityStateComplexBaseType complex type is
an abstract type that extends the
EntityComplexBaseType and is used by some
entities within an OVAL
State.
The optional
check_existence attribute specifies how to
interpret the status of corresponding item
entities when performing an item-state
comparison. The default value for this
attribute is 'at_least_one_exists'
indicating that by default an item
comparison may evaluate to true only if at
least one corresponding item entity has a
status of 'exists'. For example, if a
value of 'none_exist' is given, then the
comparison can evaluate to true only if
there are one or more corresponding item
entities, each with a status of 'does not
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exist'.
The optional entity_check
attribute specifies how to handle multiple
item entities with the same name in the
OVAL Systems Characteristics file. For
example, suppose we are dealing with a
Group Test and an entity in the state is
related to the user. It is very likely
that when the information about the group
is collected off of the system (and
represented in the OVAL System
Characteristics file) that there will be
multiple users associated with the group
(i.e. multiple 'user' item entities
associated with the same 'user' state
entity). If the OVAL State defines the
value of the user entity to equal 'Fred',
then the entity_check attribute determines
if all values for 'user' item entities
must be equal to 'Fred', or at least one
value must be equal to 'Fred', etc. Note
that with the exception of the
'none_satisfy' check value, the
entity_check attribute can only affect the
result of the test if the corresponding
OVAL Item allows more than one occurrence
of the entity (e.g. 'maxOccurs' is some
value greater than
one).
The entity_check and
var_check attributes are considered
together when evaluating a single state
entity. When a variable identifies more
than one value and multiple item entities
with the same name exist, for a single
state entity, a many-to-many comparison
must be conducted. In this situation,
there are many values for the state entity
that must be compared to many item
entities. Each item entity is compared to
the state entity. For each item entity, an
interim result is calculated by using the
var_check attribute to combine the result
of comparing each variable value with a
single system value. Then these interim
results are combined for each system value
using the entity_check
attribute.
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The
EntityStateIPAddressType type is extended
by the entities of an individual OVAL
State. This type provides uniformity to
each object entity by including the
attributes found in the
EntityStateSimpleBaseType. This specific
type describes any IPv4/IPv6 address or
address prefix.
The
EntityStateIPAddressStringType type is
extended by the entities of an individual
OVAL State. This type provides uniformity
to each object entity by including the
attributes found in the
EntityStateSimpleBaseType. This specific
type describes any IPv4/IPv6 address,
address prefix, or its string
representation.
The
EntityStateAnySimpleType type is extended
by the entities of an individual OVAL
State. This type provides uniformity to
each state entity by including the
attributes found in the
EntityStateSimpleBaseType. This specific
type describes any simple
data.
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The EntityStateBinaryType
type is extended by the entities of an
individual OVAL State. This type provides
uniformity to each state entity by
including the attributes found in the
EntityStateSimpleBaseType. This specific
type describes simple binary data. The
empty string is also allowed when using a
variable reference with an
element.
The EntityStateBoolType
type is extended by the entities of an
individual OVAL State. This type provides
uniformity to each state entity by
including the attributes found in the
EntityStateSimpleBaseType. This specific
type describes simple boolean data. The
empty string is also allowed when using a
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variable reference with an
element.
The EntityStateFloatType
type is extended by the entities of an
individual OVAL State. This type provides
uniformity to each state entity by
including the attributes found in the
EntityStateSimpleBaseType. This specific
type describes simple float data. The
empty string is also allowed when using a
variable reference with an
element.
The EntityStateIntType
type is extended by the entities of an
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individual OVAL State. This type provides
uniformity to each state entity by
including the attributes found in the
EntityStateSimpleBaseType. This specific
type describes simple integer data. The
empty string is also allowed when using a
variable reference with an
element.
The
EntityStateEVRStringType type is extended
by the entities of an individual OVAL
State. This type provides uniformity to
each state entity by including the
attributes found in the
EntityStateSimpleBaseType. This type
represents the epoch, version, and release
fields, for an RPM package, as a single
version string. It has the form
"EPOCH:VERSION-RELEASE". Note that a null
epoch (or '(none)' as returned by rpm) is
equivalent to '0' and would hence have the
form 0:VERSION-RELEASE. Comparisons
involving this datatype should follow the
algorithm of librpm's rpmvercmp()
function.
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The
EntityStateDebianEVRStringType type is
extended by the entities of an individual
OVAL State. This type provides uniformity
to each state entity by including the
attributes found in the
EntityStateSimpleBaseType. This type
represents the epoch, upstream_version,
and debian_revision fields, for a Debian
package, as a single version string. It
has the form
"EPOCH:UPSTREAM_VERSION-DEBIAN_REVISION".
Note that a null epoch (or '(none)' as
returned by dpkg) is equivalent to '0' and
would hence have the form
0:UPSTREAM_VERSION-DEBIAN_REVISION.
Comparisons involving this datatype should
follow the algorithm outlined in Chapter 5
of the "Debian Policy Manual"
(https://www.debian.org/doc/debian-policy/
ch-controlfields.html#s-f-Version).
An implementation of this is the
cmpversions() function in dpkg's
enquiry.c.
The
EntityStateVersionType type is extended by
the entities of an individual OVAL State.
This type provides uniformity to each
state entity by including the attributes
found in the EntityStateSimpleBaseType.
This specific type describes simple
version data.
The
EntityStateFileSetRevisionType type is
extended by the entities of an individual
OVAL State. This type provides uniformity
to each state entity by including the
attributes found in the
EntityStateSimpleBaseType. This specific
type represents the version string related
to filesets in HP-UX.
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The
EntityStateIOSVersionType type is extended
by the entities of an individual OVAL
State. This type provides uniformity to
each state entity by including the
attributes found in the
EntityStateSimpleBaseType. This specific
type represents the version string related
to CISCO IOS.
'string' is
included to allow for regular
expressions on IOS version
strings.
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The EntityStateStringType
type is extended by the entities of an
individual OVAL State. This type provides
uniformity to each state entity by
including the attributes found in the
EntityStateSimpleBaseType. This specific
type describes simple string
data.
The EntityStateRecordType
defines an entity that consists of a
number of uniquely named fields. This
structure is used for representing a
record from a database query and other
similar structures where multiple related
fields must be collected at once. Note
that for all entities of this type, the
only allowed datatype is 'record' and the
only allowed operation is 'equals'. During
analysis of a system characteristics item,
each field is analyzed and then the
overall result for elements of this type
is computed by logically anding the
results for each field and then applying
the entity_check
attribute.
Note the datatype
attribute must be set to
'record'.
Note the operation
attribute must be set to
'equals'.
Note the var_ref
attribute is not permitted and the
var_check attribute does not
apply.
Note that when the mask
attribute is set to 'true', all child
field elements must be masked regardless
of the child field's mask attribute
value.
The EntityStateFieldType
defines an element with simple content
that represents a named field in a record
that may contain any number of named
fields. The EntityStateFieldType is much
like all other entities with one
significant difference, the
EntityStateFieldType has a name
attribute
The required name
attribute specifies a unique name for the
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field. Field names are lowercase and must
be unique within a given parent record
element. When analyzing system
characteristics an error should be
reported for the result of a field that is
present in the OVAL State, but not found
in the system characteristics
Item.
The optional entity_check
attribute specifies how to handle multiple
record fields with the same name in the
OVAL Systems Characteristics file. For
example, while collecting group
information where one field is the
represents the users that are members of
the group. It is very likely that there
will be multiple fields with a name of
'user' associated with the group. If the
OVAL State defines the value of the field
with name equal 'user' to equal 'Fred',
then the entity_check attribute determines
if all values for field entities must be
equal to 'Fred', or at least one value
must be equal to 'Fred',
etc.
Note that when the mask
attribute is set to 'true' on a field's
parent element the field must be masked
regardless of the field's mask attribute
value.
A string restricted
to disallow upper case
characters.
83. Intellectual Property Considerations
Copyright (C) 2010 United States Government. All Rights Reserved.
DHS, on behalf of the United States, owns the registered OVAL
trademarks, identifying the OVAL STANDARDS SUITE and any component
part, as that suite has been provided to the IETF Trust. A "(R)"
will be used in conjunction with the first use of any OVAL trademark
in any document or publication in recognition of DHS's trademark
ownership.
84. Acknowledgements
The authors wish to thank DHS for sponsoring the OVAL effort over the
years which has made this work possible. The authors also wish to
thank the original authors of this document Jonathan Baker, Matthew
Hansbury, and Daniel Haynes of the MITRE Corporation as well as the
OVAL Community for its assistance in contributing and reviewing the
original document. The authors would also like to acknowledge Dave
Waltermire of NIST for his contribution to the development of the
original document.
85. IANA Considerations
This memo includes no request to IANA.
86. Security Considerations
While OVAL is just a set of data models and does not directly
introduce security concerns, it does provide a mechanism by which to
represent endpoint posture assessment information. This information
could be extremely valuable to an attacker allowing them to learn
about very sensitive information including, but, not limited to:
security policies, systems on the network, criticality of systems,
software and hardware inventory, patch levels, user accounts and much
more. To address this concern, all endpoint posture assessment
information should be protected while in transit and at rest.
Furthermore, it should only be shared with parties that are
authorized to receive it.
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Another possible security concern is due to the fact that content
expressed as OVAL has the ability to impact how a security tool
operates. For example, content may instruct a tool to collect
certain information off a system or may be used to drive follow-up
actions like remediation. As a result, it is important for security
tools to ensure that they are obtaining OVAL content from a trusted
source, that it has not been modified in transit, and that proper
validation is performed in order to ensure it does not contain
malicious data.
87. References
87.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
.
[WIN-FILETIME]
Microsoft Corporation, "File Times", 2015,
.
87.2. Informative References
[OVAL-WEBSITE]
The MITRE Corporation, "The Open Vulnerability and
Assessment Language", 2015,
.
Authors' Addresses
Michael Cokus
The MITRE Corporation
903 Enterprise Parkway, Suite 200
Hampton, VA 23666
USA
Email: msc@mitre.org
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Daniel Haynes
The MITRE Corporation
202 Burlington Road
Bedford, MA 01730
USA
Email: dhaynes@mitre.org
David Rothenberg
The MITRE Corporation
202 Burlington Road
Bedford, MA 01730
USA
Email: drothenberg@mitre.org
Juan Gonzalez
Department of Homeland Security
245 Murray Lane
Washington, DC 20548
USA
Email: juan.gonzalez@dhs.gov
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