VERSION 2.0 The Open Checklist Interactive Language (OCIL) is a language to express a set of questions to be presented to a user and procedures to interpret responses to these questions for the purpose of developing security checklists. Although its intended domain of use is IT security, its generic nature allows for other applications. For instance, it could be used for authoring research surveys, academic course exams, and instructional walkthroughs. This document was originally developed by David Waltermire (The Center for Internet Security) and has been revised by The MITRE Corp with input from the security benchmark community. It is intended for developers and assumes familiarity with XML. This namespace is required for xml:lang support. The ocil element is the root XML element of an OCIL document. It contains information about one or more questionnaires. It may also contain results elements to store prior responses. The generator element contains information related to the generation of the file. Specifically, a generator contains information about the application used to create the file, when it was created, and the schema to use to validate it. This element contains document-level information, including title, descriptions, and notices. The questionnaires element contains all the questionnaire constructs defined within the document. The test_actions element contains all the boolean, choice, string, and numeric test actions defined within the document. The questions element contains all the boolean, choice, string, and numeric questions, and any other supporting elements (e.g. choice group) defined within the document. The artifacts element contains all the artifact constructs to be retrieved (as necessary) during evaluation. The variables element contains all the constant, local, and external variables available to be used within the document. The results element contains the results of an evaluation of the OCIL file. This includes records of all questionnaire results, question results, and test_action results. test_actions include question_test_action and compound_test_action (Questionnaires are CompoundTestAction) This is a common base element for the question_test_action element. The question_test_action element contains a reference to a single question along with a set of handlers that indicate how processing should proceed based on the answer provided by the user. This element is abstract and is implemented in a document as a boolean_test_action, choice_test_action, numeric_test_action, or string_test_action. The type of question_test_action must match the type of question referenced. (E.g. a boolean_test_action MUST reference a boolean_question, etc..) A boolean_question_test_action element references a boolean_question and includes handlers for TRUE (YES) or FALSE (NO) responses. A choice_question_test_action element references a choice_question and includes handlers for the various choices set out in the choice_question. Ensure that no choice_test_action has multiple branches for a single choice. A numeric_question_test_action element references a numeric_question and includes handlers that indicate actions to perform based on whether the user's response matches a particular value or falls within a particular range. A string_question_test_action element references a string_question and includes handlers that indicate actions to perform based on whether the user's response matches a given regular expression. A question element contains information one question that needs to be answered by a user. It can be a boolean_question, choice_question, numeric_question, or string_question depending on the set of acceptable answers. A boolean_question is a type of question with valid responses of either {TRUE, FALSE} or {YES, NO}. A choice_question is a type of question element with one or more acceptable answers specified by the author. The user will select one of these specified answers as their response. Acceptable answers are specified either explicitly using the choice element or implicitly using the choice_group_ref element to reference a choice_group element. Choices are presented in the order in which they are provided. All the choices in a choice_group are inserted in the order in which they appear within the choice_group. A numeric_question is a type of question_element that requires a numeric answer. Acceptable values may be positive or negative and may include decimals. A string_question is a type of question element that requires a string answer. A variable element holds information defined by the author, an answer value, or values from external sources. A constant variable element holds a value defined by the author of the document. A local variable element holds a value defined during evaluation. It will try to match and set the value based on the answer to a question. An external variable element is a variable defined elsewhere (an external source). A target element describes the user, system, or role that applies to all questionnaires in scope. For instance, specifying that user Joe Smith should complete this document; applies to system with ip address of 123.45.67.89; applies to all systems functioning as (role) web servers; or all (role) administrators should complete this document. A user element contains information about a target user such as name, organization, position, email, and role. The system element constains information about the organization it belongs to, a set of ip addresses of computers/networks included in the system, descrioption about it, and the roles it performs. A question_result element contains result information associated with a specific question. The specific type of question_result (boolean_question_result, choice_question_result, etc.) depends on the type of the associated question (boolean_question, choice_question, etc.) A boolean_question_result element contains a reference to a boolean_question, the user's response, and whether the question was successfully posed. A choice_question_result element contains a reference to a choice_question, the user's response, and whether the question was successfully posed. A numeric_question_result element contains a reference to a numeric_question, the result provided by the user, and whether the question was successfully posed. A string_question_result element contains a reference to a string_question, the string provided by the user in response, and whether the question was successfully posed. The QuestionnairesType type defines a container for a set of questionnaire elements. A questionnaire contains a set of questions that determines compliance with a check. Each questionnaire returns a value based on the responses to the various questions that it references. Each questionnaire should represent a single compliance check, such as might be referenced by an XCCDF Rule. This specifies the test_actions referenced by the questionnaires in this document should be evaluated. If a value of FULL is provided, then all test_actions in a questionnaire will be evaluated regardless of whether the result can be known ahead of time. If a value of SHORT is provided a questionnaire will stop evaluating test_actions as soon as the final result has been determined. (For example, if one test_action evaluates to FAIL and the test_actions of a questionnaire are being ANDed together, the result is immediately known to be FAIL regardless of the results of other test_actions. If the scope is FULL, even though it is known that the questionnaire will return FAIL, the other test_actions will still be evaluated. If the scope is SHORT, no further test_actions would be evaluated since the final result had been determined.) The QuestionnaireType type defines a structure that represents specific question or set of questions that evaluate to a single result. A questionnaire may contain multiple test_actions. test_actions may be nested and aggregated thru some acceptable operation to produce the result of a check. Each questionnaire is required to have a unique identifier that conforms to the definition of NCName in the Recommendation "Namespaces in XML 1.0", i.e., all XML 1.0 names that does not contain colons. Priority is an optional attribute that can either be HIGH, MEDIUM or LOW. It specifies the importance of a paritcular test action reference. This attribute specifies whether or not this questionnaire should only appear as a child of another questionnaire. All questionnaires must be defined within the body of the ocil element and, by default, interpreters might simply grab all questionnaires and present them to a user. However, questionnaires can reference other questionnaires through a test_action_ref. If an author references a questionnaire in this way they may not wish that the questionnaire be presented to a user except as a child of another questionnaire. By setting the child_only attribute to true, the author is indicating that the given questionnaire should not be a "top-level" questionnaire but should instead only be presented as the child of another questionnaire. The GeneratorType type defines an element that is used to hold information about when a particular OCIL document was generated, what version of the schema was used, what tool was used to generate the document, and what version of the tool was used. Additional generator information is also allowed although it is not part of the official OCIL language. Individual organizations can place generator information that they feel are important. The optional product_name specifies the name of the application used to generate the file. The optional product_version specifies the version of the application used to generate the file. Identifies one of the authors of this document The required schema_version specifies the version of the OCIL schema that the document has been written in and that should be used for validation. The required timestamp specifies when the particular OCIL document was generated. The format for the timestamp is yyyy-mm-ddThh:mm:ss. This type describes structures used to provide document-level information, including title, descriptions, and notices. Used to provide a title for this document Each description element contains part of an overall description for the entire document. (Note that questionnaires contain their own description for questionnaire specific descriptions.) Each notice contains a notice or warning to the user of this document. Provides possible scope values that specifies when evaluation stops. The FULL value indicates that all questions must be asked regardless of whether or not it they are all needed to produce a result for a questionnaire. The SHORT value indicates that once a result value can be computed for a questionnaire, then it is safe to stop asking questions. The TestActionsType type defines a container for a set of test action elements. The test_action element contains information about what action to take based on the answer to a referenced question element within a questionnaire. It can be a compound_test_action, boolean_question_test_action, choice_question_test_action, numeric_question_test_action, or string_question_test_action. The QuestionTestActionType type defines structures that are used to hold handlers for non-standard results (UNKNOWN, NOT_TESTED, NOT_APPLICABLE, and ERROR) received from a referenced question. All children of question_test_action extend this type. The title element contains a descriptive heading for this set of handlers. The when_unknown element contains processing instructions for when when the received result is UNKNOWN. The when_not_tested element contains processing instructions for when when the received result is NOT_TESTED. The when_not_applicable element contains processing instructions for when when the received result is NOT_APPLICABLE. The when_error element contains processing instructions for when when the received result is ERROR. The question_ref attribute contains the id value of a question element. Each item is required to have a unique identifier that conforms to the definition of NCName in the Recommendation "Namespaces in XML 1.0", i.e., all XML 1.0 names that does not contain colons. The BooleanQuestionTestActionType type defines a structure that references a boolean_question and includes handlers for TRUE (YES) or FALSE (NO) responses. The element when_true specifies the action to do when the answer is true. The element when_false specifies the action to do when the answer is false. The ChoiceQuestionTestActionType type defines a structure that references a choice_question and includes handlers for the various choices set out in the choice_question. Specifies the action to perform when the indicated choice is selected by the user. The NumericQuestionTestActionType type defines a structure that references a numeric_question and includes handlers that indicate actions to perform based on whether the user's response matches a particular value or falls within a particular range. This structure is used to ensure that any number of when_equals and when_range handlers may appear, but there must be at least one handler (of one type or the other) and any when_equals handlers must precede any when_range. This element holds information on what to do when the answer matches the specified value. This element holds information on what to do when the answer is within a specified range of values. This element holds information on what to do when the answer is within a specified range of values. The StringQuestionTestActionType type defines a structure that references a string_question and includes handlers that indicate actions to perform based on whether the user's response matches a given regular expression. This element holds information on what to do when the answer matches a specified regular expression pattern. The TestActionRefType type defines a structure that holds a reference (id) to a test_action or questionnaire. The negate attribute can be used to specify whether to toggle the result from PASS to FAIL, and vice versa. A result other than PASS or FAIL (e.g. ERROR, NOT_TESTED, etc.) will be unchanged by a negate operation. Priority is an optional attribute that can either be HIGH, MEDIUM or LOW. It specifies the importance of a priority test action reference. The WhenChoiceType type defines a structure that specifies the action to take in a choice_test_action when a particular choice is selected by a user in response to a choice_question. The choice_ref element specifies the id of a choice. The WhenEqualsType defines a structure that specifies the action to take in a numeric_test_action when a particular value is given by a user in response to a numeric_question. Each value holds what is to be matched. The WhenRangeType type defines a structure that specifies the action to take in a numeric_test_action when a value given by a user in response to a numeric_question falls within the indicated range. Each range element holds a single numeric range. The WhenPatternType type defines a structure that specifies the action to take in a string_test_action when a string given by a user in response to a string_question matches the given regular expression. Each pattern element holds a regular expression against which the user's response string is to be compared. The PatternType type defines a structure that specifies a regular expression against which a string will be compared. This contents of this field must be a Perl Compatable Regular Expression (PCRE). The RangeType type defines a structure that specifies a range against which a numeric user response is to be compared. The min element contains a minimum value. The max element contains a maximum value. The ResultChoiceType complex type specifies processing instructions - either produce a result or move on to another test. The ResultChoiceType is extended by all handlers ("when_...") in test_actions. This element indicates that a final value (i.e. PASS, FAIL, ERROR, UNKNOWN, NOT_TESTED, NOT_APPLICABLE) should be returned if the encapsulating handler is invoked. This element indicates that a new test_action should be processed if the encapsulating handler is invoked. The artifacts element contains all the artifacts that must be requested when a question, test action, or questionnaire has been evaluated. The inclusive attribute specifies whether the value should be in the specified range. The default is true, indicating it is included. The QuestionsType type defines structures containing a set of QuestionType and ChoiceGroupType elements. The question element contains information for a single question to be answered. Based on the data type of acceptable answers to the question, it can be a boolean_question, choice_question, numeric_question, or string_question. Holds choice groups which represent possible sets of choices for choice_questions. Choice_groups may be reused across multiple choice_questions. The QuestionType complex type defines a structure to describe a question and any instructions to help in determining an answer. Provides the text of the question to pose to the user. An optional instructions field may be included to hold additional instructions to assist the user in determining the answer to the question. Each item is required to have a unique identifier that conforms to the definition of NCName in the Recommendation "Namespaces in XML 1.0", i.e., all XML 1.0 names that does not contain colons. The BooleanQuestionType type defines a question with valid responses of either {TRUE, FALSE} or {YES, NO}. The default_answer attribute specifies the default value of the boolean_question. Its value may be set to true or false. The model attribute specifies whether to the user should respond with {True, False} or {YES, NO}. If the value of this attribute is not set, then it defaults to MODEL_YES_NO (i.e. response can either be YES or NO). The ChoiceQuestionType type defines a question with one or more acceptable answers specified by the author. The user will select one of these specified answers as their response. Acceptable answers are specified either explicitly using the choice element or implicitly using the choice_group_ref element to reference a choice_group element. Choices are presented in the order in which they are provided. All the choices in a choice_group are inserted in the order in which they appear within the choice_group. Holds the information associated with one of the possible responses to this choice_question. Holds a reference to a choice_group. The questions described in this choice group are used as possible responses for this choice_question. The default_answer_ref specifies the choice id of the default answer to the question. The NumericQuestionType type defines a question that requires a numeric answer. Acceptable values may be positive or negative and may include decimals. An optional default value may be specified as the answer. The StringQuestionType type defines a question that requires a string answer. An optional default value may be specified as the answer. Provides the acceptable models (i.e. set of acceptable responses) for a boolean_question. MODEL_YES_NO represents a response set of {YES, NO}. MODEL_TRUE_FALSE represents a response set of {TRUE, FALSE}. The ChoiceType type defines structures that hold information about one acceptable answer to a choice_question. All choices are tagged with a unique identifier that may be referenced by a choice_test_action referencing the encapsulating choice_question. The ChoiceGroupType type defines a group of choices that may then be reused in multiple choice_question elements. For example, a document may include multiple choice_questions with the options of "Good", "Fair", or "Poor". By defining these choices in a single choice_group, the author would not need to list them out explicitly in every choice_question. Holds the information associated with one of the possible responses for a choice_question. Holds the id of this choice group. This id is referenced within choice_question elements to include the choices contained in a group. The InstructionsType type defines a series of steps intended to guide the user in answering a question. The title element contains a descriptive heading for the instructions. The step element contains a single step within the instructions. The ResultsType type defines structures containing results from questionnaires, test actions, questions, artifacts, and metadata about the start/end time of evaluation, any targets, and a short caption or title. The title element contains a descriptive heading or caption describing the result set. The questionnare_results element contains computed results of all the evaluated questionnaires. The test_action_results element contains computed results of all the evaluated test action types. The question_results element contains computed results of all evaluated question types. The artifact_results element contains all artifacts that has been retrieved during evaluation. Scope is the entire document. The targets element contains all the actual target users, systems, roles in which the OCIL document has been applied. The start_time attribute is an optional attribute the specifies when the evaluation of this OCIL file started. The end_time attribute is an optional attribute the specifies when the evaluation of this OCIL file ended. The QuestionnaireResultsType type defines structures containing computed results of all the evaluated questionnaires. The questionnaire_result element contains information about the result of a particular questionnaire. The TestActionResultsType type defines structures containing computed results of all the evaluated test action types. The test_action_result element contains the result of a test_action evaluation. One of these elements will appear for each test_action evaluated. The QuestionResultsType type defines structures containing computed results of all evaluated question types. A question_result element contains result information associated with a specific question. The specific type of question_result (boolean_question_result, choice_question_result, etc.) depends on the type of the associated question (boolean_question, choice_question, etc.) The QuestionnaireResultType type defines structures containing the computed result, associated artifacts and targets of a particular questionnaire. The artifact_results element contains a set of retrieved artifacts. The questionnaire_ref attribute identifies a particular questionnaire using its id. The result attribute holds the result of evaluating the specified questionnaire. The TestActionResultType type defines structures containing all computed results of a TestActionType. One of these elements will appear for each test_action evaluated. The artifact_results element contains a set of retrieved artifacts. The test_action_ref attribute identifies a specific test_action using its id. The result attribute holds the result of evaluating the specified test_action specified. The QuestionResultType complex type defines structures that hold information about a question and the user's response to it. The question_ref attribute contains the id of a question. The response attribute classifies the user response. If the user provides a standard answer to the question the response is set to ANSWERED (the default). If, however, the user selects an exceptional answer (UNKNOWN, NOT_APPLICABLE, etc.) then this attribute will be set to the corresponding exceptional result. The BooleanQuestionResultType type defines structures containing a reference to a boolean_question, the user's response, and whether the question was successfully posed. The value of the answer to the boolean_question. It could either be TRUE or FALSE. The ChoiceQuestionResultType type defines structures containing a reference to a choice_question, the user's response, and whether the question was successfully posed. The answer element contains a choice_ref attribute that identifies the choice selected by the user. The NumericQuestionResultType type defines structures containing a reference to a numeric_question, the result provided by the user, and whether the question was successfully posed. The decimal value of the answer to a numeric_question as provided by the user. A string_question_result element contains a reference to a string_question, the string provided by the user in response, and whether the question was successfully posed. The string value of the answer to a string_question provided by the user. The ResultType simple type defines acceptable result values for questionnaires and test_actions. || P | F | E | U | NT | NA || ---------------||-----------------------------||------------------||------------------------------------------ || 1+ | 0 | 0 | 0 | 0 | 0+ || Pass || 0+ | 1+ | 0+ | 0+ | 0+ | 0+ || Fail AND || 0+ | 0 | 1+ | 0+ | 0+ | 0+ || Error || 0+ | 0 | 0 | 1+ | 0+ | 0+ || Unknown || 0+ | 0 | 0 | 0 | 1+ | 0+ || Not Tested || 0 | 0 | 0 | 0 | 0 | 1+ || Not Applicable || 0 | 0 | 0 | 0 | 0 | 0 || Not Tested ---------------||-----------------------------||------------------||------------------------------------------ || 1+ | 0+ | 0+ | 0+ | 0+ | 0+ || Pass || 0 | 1+ | 0 | 0 | 0 | 0+ || Fail OR || 0 | 0+ | 1+ | 0+ | 0+ | 0+ || Error || 0 | 0+ | 0 | 1+ | 0+ | 0+ || Unknown || 0 | 0+ | 0 | 0 | 1+ | 0+ || Not Tested || 0 | 0 | 0 | 0 | 0 | 1+ || Not Applicable || 0 | 0 | 0 | 0 | 0 | 0 || Not Tested A PASS value indicates that the check passed its test. A FAIL value indicates that the check did not pass its test. The ExceptionalResultType type defines possible exceptional results of a question. An UNKNOWN value indicates that the result of a test cannot be determined. An ERROR value indicates that an error occured while processing the check. Among other causes, this can indicate an unexpected response from the user. A NOT_TESTED value indicates that the check has not been tested yet. A NOT_APPLICABLE value indicates that the check is not relevant and can be skipped. The UserResponseType type defines structures containing the type of response made by the user. The user could either have answered the question or have taken any of the ExceptionalResultType values. Indicates that the user responded by answering the question posed. The ChoiceAnswerType type defines structures containing a choice_ref attribute that identifies the choice selected by the user. The choice_ref attribute specifies an id of the choice selected by the user. The ArtifactsType type defines structures containing a set of artifact elements. An artifact is evidence supporting an answer, completed test action/questionnaire. Examples include a file or a submitted text. The ArtifactType type defines structures containing information about an artifact such as title, description, persistence, datatype, and/or if it's required to complete an answer to a question. The title element holds a short summary or a caption about the artifact. The description element holds information that describes what the artifact is about. Each item is required to have a unique identifier that conforms to the definition of NCName in the Recommendation "Namespaces in XML 1.0", i.e., all XML 1.0 names that does not contain colons. The persistent attribute specifies whether the artifact is time sensitive or not. If the value is true, then a snapshot or a copy must be kept. Otherwise, a pointer to the location of the artifact is enough. The default value is true. The datatype attribute specifies how to treat the value of the artifact. It can either be TEXT or REFERENCE. The default is TEXT. The required element specifies whether the artifact must be included or not. If true, then it must be included. The questionnaire is not considered complete without it. Otherwise, it is desired but not necessary. The ArtifactResultsType type defines structures containing a set of artifact_result elements. The artifact_result element contains an artifact, its value, who submitted it, and who provided it. The ArtifactResultType type defines structures containing informaiton about the submitted artifact, its value, who provided and submitted it, and when it was submitted. The value element contains either the artifact data itself or a pointer to it. The provider element contains information about the user or system that provided the artifact. The submitter element contains information about the user who submitted the artifact. The artifact_ref holds the unique identifier of the artifact object that describes what the artifact is about, the type of data it holds, and other metadata. The timestamp attribute holds the date and time when the artifact was collected. The ArtifactDataType type defines the acceptable data values for an artifact. A TEXT value specifies that the artifact is an essay entered during the evaluation. A REFERENCE value specifies that the artifact holds a reference to a file or a URL. The TargetsType type defines structures containing a set of target elements. A target element describes the user, system, or role that applies to all questionnaires in scope. For instance, specifying that user Joe Smith should complete this document; applies to system with ip address of 123.45.67.89; applies to all systems functioning as (role) web servers; or all (role) administrators should complete this document. The UserTargetType type defines structures containing information about a user such as name, organization, position, email, and role. The organization element specifies the company or institution that the user belongs to. The position element holds the job title or the position of the user within his/her organization. The email element holds the email address where the user can be contacted. The SystemTargetType type defines structures containing information about the organization it belongs to, a set of ip addresses of computers/networks included in the system, descrioption about it, and the roles it performs. The organization element specifies what company or institution the system belongs to. The ipaddress element holds the ip address of a target compuer/network. The description element holds information what the target system is about. The VariablesType type defines structures containing a set of variables. A variable element holds a value defined by the author, a value based on a question's answer, or a value from an external source. The VariableType type defines structures used to hold a single value. The description element holds information that describes the value stored on the variable. Each item is required to have a unique identifier that conforms to the definition of NCName in the Recommendation "Namespaces in XML 1.0", i.e., all XML 1.0 names that does not contain colons. The datatype attribute specifies how to treat the variable's value. It can be TEXT or NUMERIC. The ConstantVariableType type defines structures containing a value defined by the author of the document. The value element holds the data stored on the variable. The LocalVariableType type defines structures containing a value determined during evaluation. Value is computed based on the matched pattern, choice_ref, or range value, and the answer to the linked question The set element contains information describing how to compute the value to be stored on the variable. It holds the patterns, choice_refs, and range values to be matched with the answer to the linked question; and the appropriate value to be stored on the variable based on the match. The optional default_value element holds the initial value of the variable, if the linked question has not been evaluated yet. The question_ref attribute holds the unique identifier of the question in which the variable is linked. The ExternalVariableType type defines structures containing a value defined elsewhere or some external source. The optional default_value element holds the initial value of the variable, if the value cannot be retrieved from the external source. The VariableSetType type defines structures containing information describing how to compute a variable value. It holds the patterns, choice_refs, and range values to be matched; and the appropriate value to be stored on the variable based on the match. The pattern element is a string representation of the pattern to be matched. The choice_ref element holds a choice unique identifier to be matched. The range element holds a range of decimal values to matched. The value element contains the data to be stored on the variable if any of the patterns, choice_refs, or range values has been matched. The VariableDataType simple type defines how a variable data value should be treated or used. The TEXT value specifies that the variable data value should be treated as text. The NUMERIC value specifies that the variable data value should be treated as number. The ReferenceType complex type defines structures used to hold information about an external reference given its URI and description. This structure may be used to reference other standards such as CVE, CCE, or CPE. To do so, the href attribute would give the relevant namespace. For example, the namespace of the current version of CPE is http://cpe.mitre.org/dictionary/2.0 and the body of this element would hold a specific CPE identifier. References to other information (documents, web pages, etc.) are also permitted. The href attribute holds the URI of an external reference. This may be the namespace associated with the information in the body or a web URL containing relevant information. The StepType complex type defines structures that describe one step (out of possibly multiple steps) that a user should take in order to respond to a question. The steps would appear as part of the question's instructions element. The description element contains some information about this step type. The reference element contains information about any external references related to this step type. The step element contains is a substep for this step type. The is_done attribute indicates whether this step has been done. The value is true when it is done. Otherwise, it is false, It is an optional attribute that defaults to false. The is_required attribute indicates whether a step is required or not. If it is not, then it can be skipped. It is an optional attribute that defaults to true. The ItemBaseType complex type defines structures allowing a set of notes to be included. This type is inherited by many of the elements in the OCIL language. An optional set of notes to describe additional information. The TargetType type defines the user, role, or system that applies to a questionnaire or the whole OCIL document. The name element holds the tile or caption for the target. The CompoundTestActionType type describes the structures used to combine multiple test_action elements into a single result. The title element contains a descriptive heading for the set of test_actions. The description element holds information describing the set of test_actions. The references element holds one or more reference elements. Examples could include references to other standards such as CVE, CCE, or CPE. The actions element holds one or more test_action elements along with the operators used to combine them into a single result. The artifacts element contains all the artifacts that must be requested when a question, test action, or questionnaire has been evaluated. The ReferenceType complex type contains a set of references. The reference element contains information about any external references. Examples could include references to other standards such as CVE, CCE, or CPE. The OperationType type defines structures that hold a set of test_actions and provide instructions as to how to aggregate their individual results into a single result. The test_action_ref elements holds the identifier of a test_action element. At least one test_action_ref must be included. The operation attribute describes how to aggregate the results of a set of test_actions. Its value defaults to the Boolean operator "AND". The negate attribute can be used to specify whether to toggle the result from PASS to FAIL, and vice versa. A result other than PASS or FAIL (e.g. ERROR, NOT_TESTED, etc.) will be unchanged by a negate operation. Priority is an optional attribute that can either be HIGH, MEDIUM or LOW. It specifies the importance of the referenced set of test_action elements. The OperatorType simple type provides a list of possible operator values that operates on a set of test_action elements. The AND operator produces a true result if every argument is true. If one or more arguments are false, the result of the AND is false. See the truth table provided in the ResultType type for a complete list of how the various result types are combined by an AND operation. The OR operator produces a true result if one or more arguments is true. If every argument is false, the result of the OR is false. See the truth table provided in the ResultType type for a complete list of how the various result types are combined by an AND operation. The PriorityType simple type provides a list of possible priority attribute values for a set of test_action elements. The notion of importance is left to the author's discretion. A HIGH priority test_action is more important than both MEDIUM and LOW priority test_actions. A MEDIUM priority test_action is more important than LOW priority test_actions. A LOW priority test_action has less importance compared to MEDIUM and HIGH priority test_actions. The TextType complex type defines an element that holds any information. This attribute specifies the language in which to interpret the information. A test_action_ref may refer to either a test_action or a questionnaire. This type represents the union of these two ID patterns. ID values for questionnaires must match this pattern. Each ID must be unique within an OCIL document. ID values for test_actions must match this pattern. Each ID must be unique within an OCIL document. ID values for questions must match this pattern. Each ID must be unique within an OCIL document. ID values for choices in choice_questions must match this pattern. Each ID must be unique within an OCIL document. ID values for choice_group references in choice_questions must match this pattern. Each ID must be unique within an OCIL document. ID values for variable references must match this pattern. Each ID must be unique within an OCIL document. ID values for artifact references must match this pattern. Each ID must be unique within an OCIL document. Provider for artifacts may be a user or a system. This type represents the union of these two ID patterns.