Terraform AWS SSO Group

This module provisions AWS IAM Identity Center (formerly AWS Single Sign-On) resources:

• An Identity Store group and group memberships for each user that is specified (the module does not provision users for you)
  • Alternatively, you may supply your own pre-existing Identity Store group. This is especially useful if you make use of an external IdP such as Okta. In this case, set create_group = false but still provide the group_name. You should also omit users to avoid drift from the IdP.
• A Permission Set with options for inline, AWS-managed, and customer-managed policy attachments to attach to the group
• Account assignments provisioning the permission set in each specified account

Prerequisites

• In order to use AWS IAM Identity Center, your account must be managed by AWS Organizations.
• At the time of this writing (2023-11-09), you must manually click the Enable button in the AWS IAM Identity Center web console to create an instance in your account

Usage

Example where you wish to provision users and groups

data "aws_caller_identity" "current" {}

data "aws_ssoadmin_instances" "this" {}

variable "another_account_id" {
  description = "ID of another account within the organization"
  type        = string
  default     = "000000000000"
}

variable "users" {
  description = "users"
  type        = map(map(string))
  default = {
    "John Doe" = {
      username = "jdoe"
      email    = "[email protected]"
    },
    "John Smith" = {
      username = "jsmith"
      email    = "[email protected]"
    },
    "Joe Bloggs" = {
      username = "jbloggs"
      email    = "[email protected]"
    }
  }
}

resource "aws_identitystore_user" "user" {
  for_each = var.users

  identity_store_id = tolist(data.aws_ssoadmin_instances.this.identity_store_ids)[0]

  display_name = each.key
  user_name    = each.value["username"]

  name {
    given_name  = split(" ", each.key)[0]
    family_name = split(" ", each.key)[1]
  }

  emails {
    primary = true
    value   = each.value["email"]
  }
}

module "sso_group" {
  source = "trussworks/sso-group/aws"
  version = "~> 1.0"

  group_name          = "group-name"
  permission_set_name = "permission-set-name"

  accounts = [
    data.aws_caller_identity_current.account_id,
    var.another_account_id
  ]

  users = [
    for user in aws_identitystore_user.user : user.user_name => user.user_id
  ]

  policy_aws_managed = [
    "arn:aws:iam::aws:policy/AdministratorAccess"
  ]
}

Example where an external IdP + SCIM handles users and groups

module "sre_admin" {
  source  = "trussworks/sso-group/aws"
  version = "~> 1.0"

  accounts = [
    data.aws_caller_identity_current.account_id,
    var.another_account_id
  ]

  create_group = false

  group_name = "group-name" # must match the group name that already exists

  permission_set_name = "permission-set-name"

  policy_aws_managed = [
    "arn:aws:iam::aws:policy/AdministratorAccess"
  ]
}

Requirements

Name	Version
terraform	~> 1.6
aws	~> 5.0

Providers

Name	Version
aws	~> 5.0

Modules

No modules.

Resources

Name	Type
aws_identitystore_group.this	resource
aws_identitystore_group_membership.this	resource
aws_ssoadmin_account_assignment.this	resource
aws_ssoadmin_customer_managed_policy_attachment.this	resource
aws_ssoadmin_managed_policy_attachment.this	resource
aws_ssoadmin_permission_set.this	resource
aws_ssoadmin_permission_set_inline_policy.this	resource
aws_caller_identity.this	data source
aws_identitystore_group.this	data source
aws_ssoadmin_instances.this	data source

Inputs

Name	Description	Type	Default	Required
accounts	List of accounts in which the permission set is to be provisioned	list(string)	n/a	yes
create_group	Whether to create a new usergroup. Defaults to true so that updates don't cause issues	bool	true	no
group_description	Description of the user group	string	"N/A"	no
group_name	The display name of the group being created	string	n/a	yes
permission_set_description	Description of the permission set	string	"N/A"	no
permission_set_name	Name of the permission set	string	n/a	yes
policy_aws_managed	List of ARNs of policies to attach to permission set	list(string)	[]	no
policy_customer_managed_name	Name of the policy to attach to permission set	string	""	no
policy_customer_managed_path	Path of the policy to attach to permission set	string	"/"	no
policy_inline	Inline policy in JSON format to attach to permission set	string	""	no
session_duration	The user session duration in ISO-8601 format	string	"PT1H"	no
users	List of users to add to group	map(string)	{}	no

Outputs

Name	Description
group_id	the ID of the identity store group
permission_set_arn	the ARN of the permission set

Developer Setup

Install dependencies (macOS)

brew install pre-commit tfenv terraform-docs
tfenv install
pre-commit install --install-hooks