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terraform-aws-modules/terraform-aws-kms

AWS KMS Terraform module

Terraform module which creates AWS KMS resources.

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Usage

See examples directory for working examples to reference:

Autoscaling Service Linked Role

Reference usage for EC2 AutoScaling service linked role to launch encrypted EBS volumes:

module "kms" {
  source = "terraform-aws-modules/kms/aws"

  description = "EC2 AutoScaling key usage"
  key_usage   = "ENCRYPT_DECRYPT"

  # Policy
  key_administrators                 = ["arn:aws:iam::012345678901:role/admin"]
  key_service_roles_for_autoscaling  = ["arn:aws:iam::012345678901:role/aws-service-role/autoscaling.amazonaws.com/AWSServiceRoleForAutoScaling"]

  # Aliases
  aliases = ["mycompany/ebs"]

  tags = {
    Terraform   = "true"
    Environment = "dev"
  }
}

External Key

Reference usage for external CMK (externally provided encryption material):

module "kms" {
  source = "terraform-aws-modules/kms/aws"

  description         = "External key example"
  key_material_base64 = "Wblj06fduthWggmsT0cLVoIMOkeLbc2kVfMud77i/JY="
  valid_to            = "2085-04-12T23:20:50.52Z"

  # Policy
  key_owners         = ["arn:aws:iam::012345678901:role/owner"]
  key_administrators = ["arn:aws:iam::012345678901:role/admin"]
  key_users          = ["arn:aws:iam::012345678901:role/user"]
  key_service_users  = ["arn:aws:iam::012345678901:role/ec2-role"]

  # Aliases
  aliases                 = ["mycompany/external"]
  aliases_use_name_prefix = true

  # Grants
  grants = {
    lambda = {
      grantee_principal = "arn:aws:iam::012345678901:role/lambda-function"
      operations        = ["Encrypt", "Decrypt", "GenerateDataKey"]
      constraints = {
        encryption_context_equals = {
          Department = "Finance"
        }
      }
    }
  }

  tags = {
    Terraform   = "true"
    Environment = "dev"
  }
}

Reference

Reference usage showing available configurations.

module "kms" {
  source = "terraform-aws-modules/kms/aws"

  description             = "Complete key example showing various configurations available"
  deletion_window_in_days = 7
  enable_key_rotation     = true
  is_enabled              = true
  key_usage               = "ENCRYPT_DECRYPT"
  multi_region            = false

  # Policy
  enable_default_policy                  = true
  key_owners                             = ["arn:aws:iam::012345678901:role/owner"]
  key_administrators                     = ["arn:aws:iam::012345678901:role/admin"]
  key_users                              = ["arn:aws:iam::012345678901:role/user"]
  key_service_users                      = ["arn:aws:iam::012345678901:role/ec2-role"]
  key_symmetric_encryption_users         = ["arn:aws:iam::012345678901:role/symmetric-user"]
  key_hmac_users                         = ["arn:aws:iam::012345678901:role/hmac-user"]
  key_asymmetric_public_encryption_users = ["arn:aws:iam::012345678901:role/asymmetric-public-user"]
  key_asymmetric_sign_verify_users       = ["arn:aws:iam::012345678901:role/sign-verify-user"]

  # Aliases
  aliases = ["one", "foo/bar"] # accepts static strings only
  computed_aliases = {
    ex = {
      # Sometimes you want to pass in an upstream attribute as the name and
      # that conflicts with using `for_each over a `toset()` since the value is not
      # known until after applying. Instead, we can use `computed_aliases` to work
      # around this limitation
      # Reference: https://github.com/hashicorp/terraform/issues/30937
      name = aws_iam_role.lambda.name
    }
  }
  aliases_use_name_prefix = true

  # Grants
  grants = {
    lambda = {
      grantee_principal = "arn:aws:iam::012345678901:role/lambda-function"
      operations        = ["Encrypt", "Decrypt", "GenerateDataKey"]
      constraints = {
        encryption_context_equals = {
          Department = "Finance"
        }
      }
    }
  }

  tags = {
    Terraform   = "true"
    Environment = "dev"
  }
}

Examples

Examples codified under the examples are intended to give users references for how to use the module(s) as well as testing/validating changes to the source code of the module. If contributing to the project, please be sure to make any appropriate updates to the relevant examples to allow maintainers to test your changes and to keep the examples up to date for users. Thank you!

Requirements

Name Version
terraform >= 1.3
aws >= 5.49

Providers

Name Version
aws >= 5.49

Modules

No modules.

Resources

Name Type
aws_kms_alias.this resource
aws_kms_external_key.this resource
aws_kms_grant.this resource
aws_kms_key.this resource
aws_kms_replica_external_key.this resource
aws_kms_replica_key.this resource
aws_caller_identity.current data source
aws_iam_policy_document.this data source
aws_partition.current data source

Inputs

Name Description Type Default Required
aliases A list of aliases to create. Note - due to the use of toset(), values must be static strings and not computed values list(string) [] no
aliases_use_name_prefix Determines whether the alias name is used as a prefix bool false no
bypass_policy_lockout_safety_check A flag to indicate whether to bypass the key policy lockout safety check. Setting this value to true increases the risk that the KMS key becomes unmanageable bool null no
computed_aliases A map of aliases to create. Values provided via the name key of the map can be computed from upstream resources any {} no
create Determines whether resources will be created (affects all resources) bool true no
create_external Determines whether an external CMK (externally provided material) will be created or a standard CMK (AWS provided material) bool false no
create_replica Determines whether a replica standard CMK will be created (AWS provided material) bool false no
create_replica_external Determines whether a replica external CMK will be created (externally provided material) bool false no
custom_key_store_id ID of the KMS Custom Key Store where the key will be stored instead of KMS (eg CloudHSM). string null no
customer_master_key_spec Specifies whether the key contains a symmetric key or an asymmetric key pair and the encryption algorithms or signing algorithms that the key supports. Valid values: SYMMETRIC_DEFAULT, RSA_2048, RSA_3072, RSA_4096, HMAC_256, ECC_NIST_P256, ECC_NIST_P384, ECC_NIST_P521, or ECC_SECG_P256K1. Defaults to SYMMETRIC_DEFAULT string null no
deletion_window_in_days The waiting period, specified in number of days. After the waiting period ends, AWS KMS deletes the KMS key. If you specify a value, it must be between 7 and 30, inclusive. If you do not specify a value, it defaults to 30 number null no
description The description of the key as viewed in AWS console string null no
enable_default_policy Specifies whether to enable the default key policy. Defaults to true bool true no
enable_key_rotation Specifies whether key rotation is enabled. Defaults to true bool true no
enable_route53_dnssec Determines whether the KMS policy used for Route53 DNSSEC signing is enabled bool false no
grants A map of grant definitions to create any {} no
is_enabled Specifies whether the key is enabled. Defaults to true bool null no
key_administrators A list of IAM ARNs for key administrators list(string) [] no
key_asymmetric_public_encryption_users A list of IAM ARNs for key asymmetric public encryption users list(string) [] no
key_asymmetric_sign_verify_users A list of IAM ARNs for key asymmetric sign and verify users list(string) [] no
key_hmac_users A list of IAM ARNs for key HMAC users list(string) [] no
key_material_base64 Base64 encoded 256-bit symmetric encryption key material to import. The CMK is permanently associated with this key material. External key only string null no
key_owners A list of IAM ARNs for those who will have full key permissions (kms:*) list(string) [] no
key_service_roles_for_autoscaling A list of IAM ARNs for AWSServiceRoleForAutoScaling roles list(string) [] no
key_service_users A list of IAM ARNs for key service users list(string) [] no
key_statements A map of IAM policy statements for custom permission usage any {} no
key_symmetric_encryption_users A list of IAM ARNs for key symmetric encryption users list(string) [] no
key_usage Specifies the intended use of the key. Valid values: ENCRYPT_DECRYPT or SIGN_VERIFY. Defaults to ENCRYPT_DECRYPT string null no
key_users A list of IAM ARNs for key users list(string) [] no
multi_region Indicates whether the KMS key is a multi-Region (true) or regional (false) key. Defaults to false bool false no
override_policy_documents List of IAM policy documents that are merged together into the exported document. In merging, statements with non-blank sids will override statements with the same sid list(string) [] no
policy A valid policy JSON document. Although this is a key policy, not an IAM policy, an aws_iam_policy_document, in the form that designates a principal, can be used string null no
primary_external_key_arn The primary external key arn of a multi-region replica external key string null no
primary_key_arn The primary key arn of a multi-region replica key string null no
rotation_period_in_days Custom period of time between each rotation date. Must be a number between 90 and 2560 (inclusive) number null no
route53_dnssec_sources A list of maps containing account_ids and Route53 hosted_zone_arn that will be allowed to sign DNSSEC records list(any) [] no
source_policy_documents List of IAM policy documents that are merged together into the exported document. Statements must have unique sids list(string) [] no
tags A map of tags to add to all resources map(string) {} no
valid_to Time at which the imported key material expires. When the key material expires, AWS KMS deletes the key material and the CMK becomes unusable. If not specified, key material does not expire string null no

Outputs

Name Description
aliases A map of aliases created and their attributes
external_key_expiration_model Whether the key material expires. Empty when pending key material import, otherwise KEY_MATERIAL_EXPIRES or KEY_MATERIAL_DOES_NOT_EXPIRE
external_key_state The state of the CMK
external_key_usage The cryptographic operations for which you can use the CMK
grants A map of grants created and their attributes
key_arn The Amazon Resource Name (ARN) of the key
key_id The globally unique identifier for the key
key_policy The IAM resource policy set on the key

License

Apache-2.0 Licensed. See LICENSE.