README.md

This component is responsible for provisioning Route 53 Resolver DNS Firewall resources, including Route 53 Resolver DNS Firewall, domain lists, firewall rule groups, firewall rules, and logging configuration.

Component Features

• Domain Filtering: Creates domain lists and firewall rules to allow or block DNS queries to specific domains
• VPC Association: Associates firewall rule groups with VPCs for DNS-level network protection
• Query Logging: Optionally logs all DNS queries to an S3 bucket for auditing and analysis
• Fail-Open/Fail-Closed: Controls whether DNS resolution continues or stops if the firewall fails
• Account Verification: Optional safety check that validates Terraform is running in the correct AWS account
• Flexible Account Map: Supports both remote-state account-map lookups and static account map variables (default)

Tip

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Usage

Stack Level: Regional

Here's an example snippet for how to use this component.

# stacks/catalog/route53-resolver-dns-firewall/defaults.yaml
components:
  terraform:
    route53-resolver-dns-firewall/defaults:
      metadata:
        type: abstract
      settings:
        spacelift:
          workspace_enabled: true
      vars:
        enabled: true
        firewall_fail_open: "ENABLED"
        query_log_enabled: true
        logs_bucket_component_name: "route53-resolver-dns-firewall-logs-bucket"
        domains_config:
          allowed-domains:
            # Concat the lists of domains passed in the `domains` field and loaded from the file `domains_file`
            # The file is in the `components/terraform/route53-resolver-dns-firewall/config` folder
            domains_file: "config/allowed_domains.txt"
            domains: []
          blocked-domains:
            # Concat the lists of domains passed in the `domains` field and loaded from the file `domains_file`
            # The file is in the `components/terraform/route53-resolver-dns-firewall/config` folder
            domains_file: "config/blocked_domains.txt"
            domains: []
        rule_groups_config:
          blocked-and-allowed-domains:
            # 'priority' must be between 100 and 9900 exclusive
            priority: 101
            rules:
              allowed-domains:
                firewall_domain_list_name: "allowed-domains"
                # 'priority' must be between 100 and 9900 exclusive
                priority: 101
                action: "ALLOW"
              blocked-domains:
                firewall_domain_list_name: "blocked-domains"
                # 'priority' must be between 100 and 9900 exclusive
                priority: 200
                action: "BLOCK"
                block_response: "NXDOMAIN"

# stacks/mixins/stage/dev.yaml
import:
  - catalog/route53-resolver-dns-firewall/defaults

components:
  terraform:
    route53-resolver-dns-firewall/example:
      metadata:
        component: route53-resolver-dns-firewall
        inherits:
          - route53-resolver-dns-firewall/defaults
      vars:
        name: route53-dns-firewall-example
        vpc_component_name: vpc

Execute the following command to provision the route53-resolver-dns-firewall/example component using Atmos:

atmos terraform apply route53-resolver-dns-firewall/example -s <stack>

Requirements

Providers

Modules

Resources

Inputs

object({
    full_account_map              = map(string)
    audit_account_account_name    = optional(string, "")
    root_account_account_name     = optional(string, "")
    identity_account_account_name = optional(string, "")
    aws_partition                 = optional(string, "aws")
    iam_role_arn_templates        = optional(map(string), {})
  })

{
  "audit_account_account_name": "",
  "aws_partition": "aws",
  "full_account_map": {},
  "iam_role_arn_templates": {},
  "identity_account_account_name": "",
  "root_account_account_name": ""
}

{
  "additional_tag_map": {},
  "attributes": [],
  "delimiter": null,
  "descriptor_formats": {},
  "enabled": true,
  "environment": null,
  "id_length_limit": null,
  "label_key_case": null,
  "label_order": [],
  "label_value_case": null,
  "labels_as_tags": [
    "unset"
  ],
  "name": null,
  "namespace": null,
  "regex_replace_chars": null,
  "stage": null,
  "tags": {},
  "tenant": null
}

map(object({
    domains      = optional(list(string))
    domains_file = optional(string)
  }))

[
  "default"
]

map(object({
    priority            = number
    mutation_protection = optional(string)
    # https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/route53_resolver_firewall_rule
    rules = map(object({
      action                    = string
      priority                  = number
      block_override_dns_type   = optional(string)
      block_override_domain     = optional(string)
      block_override_ttl        = optional(number)
      block_response            = optional(string)
      firewall_domain_list_name = optional(string)
      firewall_domain_list_id   = optional(string)
    }))
  }))

Outputs

Related Projects

Check out these related projects.

• Cloud Posse Terraform Modules - Our collection of reusable Terraform modules used by our reference architectures.
• Atmos - Atmos is like docker-compose but for your infrastructure

References

For additional context, refer to some of these links.

• Deploy centralized traffic filtering using AWS Network Firewall -
• AWS Network Firewall – New Managed Firewall Service in VPC -
• Deployment models for AWS Network Firewall -
• Deployment models for AWS Network Firewall with VPC routing enhancements -
• Inspection Deployment Models with AWS Network Firewall -
• How to deploy AWS Network Firewall by using AWS Firewall Manager -
• A Deep Dive into AWS Transit Gateway -
• Appliance in a shared services VPC -
• Quotas on Route 53 Resolver DNS Firewall -
• Unified bad hosts -
• cloudposse-terraform-components - Cloud Posse's upstream component

✨ Contributing

This project is under active development, and we encourage contributions from our community.

Many thanks to our outstanding contributors:

For 🐛 bug reports & feature requests, please use the issue tracker.

In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.

1. Review our Code of Conduct and Contributor Guidelines.
2. Fork the repo on GitHub
3. Clone the project to your own machine
4. Commit changes to your own branch
5. Push your work back up to your fork
6. Submit a Pull Request so that we can review your changes

NOTE: Be sure to merge the latest changes from "upstream" before making a pull request!

Running Terraform Tests

We use Atmos to streamline how Terraform tests are run. It centralizes configuration and wraps common test workflows with easy-to-use commands.

All tests are located in the test/ folder.

Under the hood, tests are powered by Terratest together with our internal Test Helpers library, providing robust infrastructure validation.

Setup dependencies:

• Install Atmos (installation guide)
• Install Go 1.24+ or newer
• Install Terraform or OpenTofu

To run tests:

• Run all tests:

  atmos test run
  

• Clean up test artifacts:

  atmos test clean
  

• Explore additional test options:

  atmos test --help
  

The configuration for test commands is centrally managed. To review what's being imported, see the atmos.yaml file.

Learn more about our automated testing in our documentation or implementing custom commands with atmos.

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License

Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

  https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.

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