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Security Modules 0.71.0Last updated in version 0.69.2

KMS Customer Managed Key Multi-Region Replication module

View SourceRelease Notes

This Terraform Module replicates an existing KMS Customer Managed Key to another region using the multi-region replication feature of KMS.

This module is intended to be used in conjunction with the kms-master-key module to replicate a KMS key managed with that module to other regions. Note that the KMS key must be marked as multi-region in order to support multi-region replication.

Sample Usage

main.tf

# ------------------------------------------------------------------------------------------------------
# DEPLOY GRUNTWORK'S KMS-CMK-REPLICA MODULE
# ------------------------------------------------------------------------------------------------------

module "kms_cmk_replica" {

source = "git::git@github.com:gruntwork-io/terraform-aws-security.git//modules/kms-cmk-replica?ref=v0.71.0"

# ----------------------------------------------------------------------------------------------------
# REQUIRED VARIABLES
# ----------------------------------------------------------------------------------------------------

# Map of CMK names to the primary CMK that the replica key is replicating. The
# primary key must already exist, and must be marked as multi_region = true.
# Each entry in var.cmk_replicas must have a corresponding entry here.
cmk_replica_primary_key_arns = <map(string)>

# Map of CMK names to spec for managing each key. Each entry in the map
# corresponds to a key that will be created by this template. Each entry in
# this map must have a corresponding entry in
# var.cmk_replica_primary_key_arns.
cmk_replicas = <any>

# ----------------------------------------------------------------------------------------------------
# OPTIONAL VARIABLES
# ----------------------------------------------------------------------------------------------------

# The default value to use for deletion_window_in_days (the number of days to
# keep this KMS Master Key around after it has been marked for deletion).
# Applies to all keys, unless overridden in the customer_master_keys map.
default_deletion_window_in_days = 30

# The default value to use for enable_key_rotation (whether or not to enable
# automatic annual rotation of the KMS key). Applies to all keys, unless
# overridden in the customer_master_keys map.
default_enable_key_rotation = true

# Create a dependency between the resources in this module to the interpolated
# values in this list (and thus the source resources). In other words, the
# resources in this module will now depend on the resources backing the values
# in this list such that those resources need to be created before the
# resources in this module, and the resources in this module need to be
# destroyed before the resources in the list.
dependencies = []

# A map of tags to apply to all KMS Keys to be created. In this map variable,
# the key is the tag name and the value is the tag value.
global_tags = {}

}


Reference

Required

cmk_replica_primary_key_arnsmap(string)required

Map of CMK names to the primary CMK that the replica key is replicating. The primary key must already exist, and must be marked as multi_region = true. Each entry in cmk_replicas must have a corresponding entry here.

cmk_replicasanyrequired

Map of CMK names to spec for managing each key. Each entry in the map corresponds to a key that will be created by this template. Each entry in this map must have a corresponding entry in cmk_replica_primary_key_arns.

Any types represent complex values of variable type. For details, please consult `variables.tf` in the source repo.
Details

Each entry in the map supports the following attributes:

OPTIONAL (defaults to value of corresponding module input):
- cmk_administrator_iam_arns list(string) : A list of IAM ARNs for users who should be given
administrator access to this CMK (e.g.
arn:aws:iam::<aws-account-id>:user/<iam-user-arn>).
- cmk_user_iam_arns list(object[CMKUser]) : A list of IAM ARNs for users who should be given
permissions to use this CMK (e.g.
arn:aws:iam::<aws-account-id>:user/<iam-user-arn>).
- cmk_read_only_user_iam_arns list(object[CMKUser]) : A list of IAM ARNs for users who should be given
read-only (decrypt-only) permissions to use this CMK (e.g.
arn:aws:iam::<aws-account-id>:user/<iam-user-arn>).
- cmk_describe_only_user_iam_arns list(object[CMKUser]) : A list of IAM ARNs for users who should be given
describe-only (kms:DescribeKey) permissions to use this CMK (e.g.
arn:aws:iam::<aws-account-id>:user/<iam-user-arn>). This is
useful for deploying services that depend on the
key (e.g., Cloudtrail) in other accounts, to trade
key aliases for CMK ARNs.
- cmk_external_user_iam_arns list(string) : A list of IAM ARNs for users from external AWS accounts
who should be given permissions to use this CMK (e.g.
arn:aws:iam::<aws-account-id>:root).
- allow_manage_key_permissions_with_iam bool : If true, both the CMK's Key Policy and IAM Policies
(permissions) can be used to grant permissions on the CMK.
If false, only the CMK's Key Policy can be used to grant
permissions on the CMK. False is more secure (and
generally preferred), but true is more flexible and
convenient.
- deletion_window_in_days number : The number of days to keep this KMS Master Key around after it has been
marked for deletion.
- tags map(string) : A map of tags to apply to the KMS Key to be created. In this map
variable, the key is the tag name and the value is the tag value. Note
that this map is merged with var.global_tags, and can be used to override
tags specified in that variable.
- enable_key_rotation bool : Whether or not to enable automatic annual rotation of the KMS key.
- cmk_service_principals list(object[ServicePrincipal]) : A list of Service Principals that should be given
permissions to use this CMK (e.g. s3.amazonaws.com). See
below for the structure of the object that should be passed
in.

Structure of ServicePrincipal object:
- name string : The name of the service principal (e.g.: s3.amazonaws.com).
- actions list(string) : The list of actions that the given service principal is allowed to
perform (e.g. ["kms:DescribeKey", "kms:GenerateDataKey"]).
- conditions list(object[Condition]) : (Optional) List of conditions to apply to the permissions for the service
principal. Use this to apply conditions on the permissions for
accessing the KMS key (e.g., only allow access for certain encryption
contexts). The condition object accepts the same fields as the condition
block on the IAM policy document (See
https://www.terraform.io/docs/providers/aws/d/iam_policy_document.htmlcondition).
Structure of CMKUser object:
- name list(string) : The list of names of the AWS principal (e.g.: arn:aws:iam::0000000000:user/dev).
- conditions list(object[Condition]) : (Optional) List of conditions to apply to the permissions for the CMK User
Use this to apply conditions on the permissions for accessing the KMS key
(e.g., only allow access for certain encryption contexts).
The condition object accepts the same fields as the condition
block on the IAM policy document (See
https://www.terraform.io/docs/providers/aws/d/iam_policy_document.htmlcondition).
Example:
cmk_replicas = {
cmk-stage = {
cmk_administrator_iam_arns = ["arn:aws:iam::0000000000:user/admin"]
cmk_user_iam_arns = [
{
name = ["arn:aws:iam::0000000000:user/dev"]
conditions = []
}
]
cmk_read_only_user_iam_arns = [
{
name = ["arn:aws:iam::0000000000:user/qa"]
conditions = []
}
]
cmk_describe_only_user_iam_arns = [
{
name = ["arn:aws:iam::0000000000:user/qa"]
conditions = []
}
]
cmk_external_user_iam_arns = ["arn:aws:iam::1111111111:user/root"]
cmk_service_principals = [
{
name = "s3.amazonaws.com"
actions = ["kms:Encrypt"]
conditions = []
}
]
}
cmk-prod = {
cmk_administrator_iam_arns = ["arn:aws:iam::0000000000:user/admin"]
cmk_user_iam_arns = [
{
name = ["arn:aws:iam::0000000000:user/prod"]
conditions = []
}
]
allow_manage_key_permissions_with_iam = true
Override the default value for all keys configured with var.default_deletion_window_in_days
deletion_window_in_days = 7

Set extra tags on the CMK for prod
tags = {
Environment = "prod"
}
}
}

Optional

The default value to use for deletion_window_in_days (the number of days to keep this KMS Master Key around after it has been marked for deletion). Applies to all keys, unless overridden in the customer_master_keys map.

30

The default value to use for enable_key_rotation (whether or not to enable automatic annual rotation of the KMS key). Applies to all keys, unless overridden in the customer_master_keys map.

true
dependencieslist(string)optional

Create a dependency between the resources in this module to the interpolated values in this list (and thus the source resources). In other words, the resources in this module will now depend on the resources backing the values in this list such that those resources need to be created before the resources in this module, and the resources in this module need to be destroyed before the resources in the list.

[]
global_tagsmap(string)optional

A map of tags to apply to all KMS Keys to be created. In this map variable, the key is the tag name and the value is the tag value.

{}