# ###################################
##       Rule Specification        ##
#####################################
# 
# Rule Identifier:
#   codebuild_project_s3_logs_encrypted_check
# 
# Description:
#   This control checks whether AWS CodeBuild projects configured with Amazon S3 logs have encryption enabled.
# 
# Reports on:
#   AWS::CodeBuild::Project
# 
# Evaluates:
#   AWS CloudFormation, AWS CloudFormation hook
# 
# Rule Parameters:
#   None
# 
# Scenarios:
#   Scenario 1:
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document does not contain any CodeBuild project resources
#      Then: SKIP
#   Scenario 2:
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains a CodeBuild project resource
#       And: 'S3Logs' in 'LogsConfig' configuration is not provided
#      Then: SKIP
#   Scenario 3:
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains a CodeBuild project resource
#       And: 'S3Logs' in 'LogsConfig' configuration is provided and its 'Status' is set to 'DISABLED'
#      Then: SKIP
#   Scenario 4:
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains a CodeBuild project resource
#       And: 'S3Logs' in 'LogsConfig' configuration is provided and its 'Status' is set to 'ENABLED'
#       And: 'EncryptionDisabled' within 'S3Logs' is provided and set to bool(true)
#      Then: FAIL
#   Scenario 5:
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains a CodeBuild project resource
#       And: 'S3Logs' in 'LogsConfig' configuration is provided and its 'Status' is set to 'ENABLED'
#       And: 'EncryptionDisabled' within 'S3Logs' is not provided
#      Then: PASS
#   Scenario 6:
#     Given: The input document is an AWS CloudFormation or CloudFormation hook document
#       And: The input document contains a CodeBuild project resource
#       And: 'S3Logs' in 'LogsConfig' configuration is provided and its 'Status' is set to 'ENABLED'
#       And: 'EncryptionDisabled' within 'S3Logs' is provided and set to bool(false)
#      Then: PASS

#
# Constants
#
let CODEBUILD_PROJECT_TYPE = "AWS::CodeBuild::Project"
let INPUT_DOCUMENT = this

#
# Assignments
#
let codebuild_project = Resources.*[ Type == %CODEBUILD_PROJECT_TYPE ]

#
# Primary Rules
#
rule codebuild_project_s3_logs_encrypted_check when is_cfn_template(%INPUT_DOCUMENT)
                                                    %codebuild_project not empty {
    check(%codebuild_project.Properties)
        <<
        [CT.CODEBUILD.PR.6]: Require encryption on all Amazon S3 logs for AWS CodeBuild projects
        [FIX]: Set 'EncryptionDisabled' in 'S3Logs' to 'false', or do not specify the 'EncryptionDisabled' property.
        >>
}

rule codebuild_project_s3_logs_encrypted_check when is_cfn_hook(%INPUT_DOCUMENT, %CODEBUILD_PROJECT_TYPE) {
    check(%INPUT_DOCUMENT.%CODEBUILD_PROJECT_TYPE.resourceProperties)
        <<
        [CT.CODEBUILD.PR.6]: Require encryption on all Amazon S3 logs for AWS CodeBuild projects
        [FIX]: Set 'EncryptionDisabled' in 'S3Logs' to 'false', or do not specify the 'EncryptionDisabled' property.
        >>
}

#
# Parameterized Rules
#
rule check(codebuild_project) {
    %codebuild_project [
        # Scenario 2 and 3
        filter_codebuild_projects(this)
    ] {
        LogsConfig {
            S3Logs {
                # Scenario 5
                EncryptionDisabled not exists or
                # Scenario 4 and 6
                EncryptionDisabled == false
            }
        }
    }
}

rule filter_codebuild_projects(codebuild_project) {
    %codebuild_project {
        LogsConfig exists
        LogsConfig is_struct
        LogsConfig {
            # Scenario 2 and 3
            S3Logs exists
            S3Logs is_struct
            S3Logs {
                Status exists
                # Scenario 3 and 4
                Status == "ENABLED"
            }
        }
    }
}

#
# Utility Rules
#
rule is_cfn_template(doc) {
    %doc {
        AWSTemplateFormatVersion exists or
        Resources exists
    }
}

rule is_cfn_hook(doc, RESOURCE_TYPE) {
    %doc.%RESOURCE_TYPE.resourceProperties exists
}