Creating templates for Custom Conformance Packs for AWS Config - AWS Config
TerminologyCustomizing the template

Creating templates for Custom Conformance Packs for AWS Config

A custom conformance pack is a unique collection of AWS Config rules and remediation actions that you can deploy together in an account and an AWS Region, or across an organization in AWS Organizations.

To make a custom conformance pack, follow the steps in the following Customizing the template section to author a YAML file that contains the list of AWS Config Managed Rules or AWS Config Custom Rules that you want to work with.

Terminology

AWS Config Managed Rules are predefined rules owned by AWS Config.

AWS Config Custom Rules are rules that you create from scratch.

There are two ways to create AWS Config custom rules: with Lambda functions (AWS Lambda Developer Guide) and with Guard (Guard GitHub Repository), a policy-as-code language. AWS Config custom rules created with AWS Lambda are called AWS Config Custom Lambda Rules and AWS Config custom rules created with Guard are called AWS Config Custom Policy Rules.

Customizing the template

Creating your YAML file

To create a YAML file, open a text editor and save the file as .yaml.

Note

Your file will contain a Parameters and Resources section.

Parameters

The Parameters section in your YAML file is for the rule parameters for the set of AWS Config rules that you will add later in the Resources section. Create the Parameters section by copying and pasting the following code block into your YAML file, customizing it as needed and repeating for each rule parameter.

Parameters:    
    NameOfRuleParamNameOfRuleParameter: 
        Default: Parameter value
        Type: Type    
    ...

For example:

Parameters:
    IamPasswordPolicyParamMinimumPasswordLength:
        Default: '14'
        Type: String
Note

When selecting the AWS Config Rules to build your custom conformance pack, check you have the resources provisioned within your account that will be evaluated for the AWS Config Rules.

  1. The first line in the parameter section after Parameters: is a concatenated string of NameOfRule + Param + NameOfRuleParameter.

    1. Replace NameOfRule with a consistent name that you create for the rule. For example, that could be IamPasswordPolicy for the iam-password-policy rule.

    2. Type Param.

    3. Then, replace NameOfRuleParameter with the name of the rule parameter for your specific rule. For AWS Config Managed Rules, the name of the rule parameter is located in the List of AWS Config Managed Rules (for example, MinimumPasswordLength is a name of a rule parameter for the iam-password-policy rule). For AWS Config Custom Rules, the name of the rule parameter is the name that you chose when you created the rule.

  2. If you are using an AWS Config Managed Rule, find the appropriate AWS Config rule in the list of managed rules so you'll know the accepted values for Default and Type for your particular rule. For AWS Config Custom Rules, use the values you selected when creating your rule.

    Note

    For each parameter, Type must be specified. Type can be one of "String", "int", "double", "CSV", "boolean" and "StringMap".

Resources

The Resources section lists the rules that are being added to your Custom Conformance Pack. Add the following Resources block directly beneath your Parameters section, customizing it as needed and repeating for each rule. For more information on the specifications, see AWS::Config::ConfigRule.

Resources:
     NameOfRule:
        Properties:
            ConfigRuleName: ActualConfigRuleName  
            InputParameters:
                NameOfRuleParameter: !Ref NameOfRuleParamNameOfRuleParameter
            Source:
                Owner: Owner
                SourceIdentifier: SOURCE_IDENTIFIER
        Type: AWS::Config::ConfigRule
     ...

For example:

Resources:
    IamPasswordPolicy:
        Properties:
            ConfigRuleName: iam-password-policy
            InputParameters:
                MinimumPasswordLength: !Ref IamPasswordPolicyParamMinimumPasswordLength
            Source:
                Owner: AWS
                SourceIdentifier: IAM_PASSWORD_POLICY
        Type: AWS::Config::ConfigRule
Note

When selecting the AWS Config rules to build your custom conformance pack, check that you have the resources that will be evaluated for the AWS Config rules provisioned within your account. For more information, see Supported Resource Types.

  1. Replace NameOfRule with the same name you created in the Parameters section.

  2. For AWS Config Managed Rules, replace ActualConfigRuleName with the title of the appropriate rule page on the List of AWS Config Managed Rules. For AWS Config Custom Rules, use the Config Rule name you chose at the time of the rule's creation.

  3. Replace NameOfRuleParameter with the same name you used in the Parameters section. After the colon, copy and paste the same concatenated string of !Ref + NameOfRule + Param + NameOfRuleParameter that you created in Parameters section.

  4. Change Owner to the appropriate value.

    Note

    AWS Config Managed Rules

    For AWS Config Managed Rules, the value for Owner will be AWS.

    AWS Config Custom Rules

    For AWS Config custom rules created with Guard, the value for Owner will be CUSTOM_POLICY. For AWS Config custom rules created with Lambda, the value for Owner will be CUSTOM_LAMBDA.

  5. Change SOURCE_IDENTIFIER to the appropriate value.

    Note

    AWS Config Managed Rules

    For AWS Config Managed Rules, copy the identifier by following the link from the rule you select from the List of AWS Config Managed Rules (for example, the source identifier for the access-keys-rotated rule is ACCESS_KEYS_ROTATED).


    AWS Config Custom Rules

    For AWS Config custom rules created with Lambda, the SourceIdentifier is the Amazon Resource Name (ARN) of the rule's AWS Lambda function, such as arn:aws:lambda:us-east-2:123456789012:function:ActualConfigRuleName. For AWS Config custom rules created with Guard, this field is not needed.

Altogether, your filled out custom conformance pack should begin to look similar to the following, which is an example using these AWS Config Managed Rules: iam-password-policy, access-keys-rotated, and iam-user-unused-credentials-check.

Parameters:
    IamPasswordPolicyParamMinimumPasswordLength:
        Default: '14'
        Type: String
    AccessKeysRotatedParamMaxAccessKeyAge:
        Default: '90'
        Type: String
    IamUserUnusedCredentialsCheckParamMaxCredentialUsageAge:
        Default: '45'
        Type: String
Resources:
    IamPasswordPolicy:
        Properties:
            ConfigRuleName: iam-password-policy
            InputParameters:
                MinimumPasswordLength: !Ref IamPasswordPolicyParamMinimumPasswordLength
            Source:
                Owner: AWS
                SourceIdentifier: IAM_PASSWORD_POLICY
        Type: AWS::Config::ConfigRule    
    AccessKeysRotated:
        Properties:
            ConfigRuleName: access-keys-rotated
            InputParameters:
                maxAccessKeyAge: !Ref AccessKeysRotatedParamMaxAccessKeyAge
            Source:
                Owner: AWS
                SourceIdentifier: ACCESS_KEYS_ROTATED
        Type: AWS::Config::ConfigRule
    IamUserUnusedCredentialsCheck:
        Properties:
            ConfigRuleName: iam-user-unused-credentials-check
            InputParameters:
                maxCredentialUsageAge: !Ref IamUserUnusedCredentialsCheckParamMaxCredentialUsageAge
            Source:
                Owner: AWS
                SourceIdentifier: IAM_USER_UNUSED_CREDENTIALS_CHECK
        Type: AWS::Config::ConfigRule