How Amazon WorkMail works with IAM

Before you use IAM to manage access to Amazon WorkMail, you should understand what IAM features are available to use with Amazon WorkMail. To get a high-level view of how Amazon WorkMail and other AWS services work with IAM, see AWS services that work with IAM in the IAM User Guide.

Amazon WorkMail identity-based policies

With IAM identity-based policies, you can specify allowed or denied actions and resources as well as the conditions under which actions are allowed or denied. Amazon WorkMail supports specific actions, resources, and condition keys. To learn about all of the elements that you use in a JSON policy, see IAM JSON Policy Elements Reference in the IAM User Guide.

Actions

Administrators can use AWS JSON policies to specify who has access to what. That is, which principal can perform actions on what resources, and under what conditions.

The Action element of a JSON policy describes the actions that you can use to allow or deny access in a policy. Policy actions usually have the same name as the associated AWS API operation. There are some exceptions, such as permission-only actions that don't have a matching API operation. There are also some operations that require multiple actions in a policy. These additional actions are called dependent actions.

Include actions in a policy to grant permissions to perform the associated operation.

Policy actions in Amazon WorkMail use the following prefix before the action: workmail:. For example, to grant someone permission to retrieve a list of users with the Amazon WorkMail ListUsers API operation, you include the workmail:ListUsers action in their policy. Policy statements must include either an Action or NotAction element. Amazon WorkMail defines its own set of actions that describe tasks that you can perform with this service.

To specify multiple actions in a single statement, separate them with commas as follows:

"Action": [
      "workmail:ListUsers",
      "workmail:DeleteUser"

You can specify multiple actions using wildcards (*). For example, to specify all actions that begin with the word List, include the following action:

"Action": "workmail:List*"

To see a list of Amazon WorkMail actions, see Actions defined by Amazon WorkMail in the IAM User Guide.

Resources

Administrators can use AWS JSON policies to specify who has access to what. That is, which principal can perform actions on what resources, and under what conditions.

The Resource JSON policy element specifies the object or objects to which the action applies. Statements must include either a Resource or a NotResource element. As a best practice, specify a resource using its Amazon Resource Name (ARN). You can do this for actions that support a specific resource type, known as resource-level permissions.

For actions that don't support resource-level permissions, such as listing operations, use a wildcard (*) to indicate that the statement applies to all resources.

"Resource": "*"

Amazon WorkMail supports resource-level permissions for Amazon WorkMail organizations.

The Amazon WorkMail organization resource has the following ARN:

arn:aws:workmail:${Region}:${Account}:organization/${OrganizationId}

For more information about the format of ARNs, see Amazon Resource Names (ARNs) and AWS service namespaces.

For example, to specify the m-n1pq2345678r901st2u3vx45x6789yza organization in your statement, use the following ARN.

"Resource": "arn:aws:workmail:us-east-1:111122223333:organization/m-n1pq2345678r901st2u3vx45x6789yza"

To specify all organizations that belong to a specific account, use the wildcard (*):

"Resource": "arn:aws:workmail:us-east-1:111122223333:organization/*"

Some Amazon WorkMail actions, such as those for creating resources, can't be performed on a specific resource. In those cases, you must use the wildcard (*).

"Resource": "*"

To see a list of Amazon WorkMail resource types and their ARNs, see Resources defined by Amazon WorkMail in the IAM User Guide. To learn with which actions you can specify for the ARN of each resource, see Actions, resources, and condition keys for Amazon WorkMail.

Condition keys

Amazon WorkMail supports the following global condition keys.

• aws:CurrentTime

• aws:EpochTime

• aws:MultiFactorAuthAge

• aws:MultiFactorAuthPresent

• aws:PrincipalOrgID

• aws:PrincipalArn

• aws:RequestedRegion

• aws:SecureTransport

• aws:UserAgent

The following example policy grants access to the Amazon WorkMail console only from MFA authenticated IAM principals in the eu-west-1 AWS Region.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "ses:Describe*",
                "ses:Get*",
                "workmail:Describe*",
                "workmail:Get*",
                "workmail:List*",
                "workmail:Search*",
                "lambda:ListFunctions",
                "iam:ListRoles",
                "logs:DescribeLogGroups",
                "cloudwatch:GetMetricData"
            ],
            "Resource": "*",
            "Condition": {
                "StringEquals": {
                    "aws:RequestedRegion": [
                        "eu-west-1"
                    ]
                },
                "Bool": {
                    "aws:MultiFactorAuthPresent": true
                }
            }
        }
    ]
}

To see all AWS global condition keys, see AWS global condition context keys in the IAM User Guide.

workmail:ImpersonationRoleId is the only service-specific condition key supported by Amazon WorkMail.

The following example policy scopes-down AssumeImpersonationRole action to a particular WorkMail organization and impersonation role.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "workmail:AssumeImpersonationRole"
      ],
      "Resource": "arn:aws:workmail:us-east-1:111122223333:organization/m-n1pq2345678r901st2u3vx45x6789yza",
      "Condition": {
        "StringEquals": {
          "workmail:ImpersonationRoleId":"12345678-1234-1234-1234-123456789012"
        }
      }
    }
  ]
}

Examples

To view examples of Amazon WorkMail identity-based policies, see Amazon WorkMail identity-based policy examples.

Amazon WorkMail resource-based policies

Amazon WorkMail does not support resource-based policies.

Authorization based on Amazon WorkMail tags

You can attach tags to Amazon WorkMail resources or pass tags in a request to Amazon WorkMail. To control access based on tags, you provide tag information in the condition element of a policy using the aws:ResourceTag/key-name, aws:RequestTag/key-name, or aws:TagKeys condition keys. For more information about tagging Amazon WorkMail resources, see Tagging an organization.

Amazon WorkMail IAM roles

An IAM role is an entity within your AWS account that has specific permissions.

Using temporary credentials with Amazon WorkMail

You can use temporary credentials to sign in with federation, assume an IAM role, or to assume a cross-account role. You obtain temporary security credentials by calling AWS STS API operations such as AssumeRole or GetFederationToken.

Amazon WorkMail supports using temporary credentials.

Service-linked roles

Service-linked roles allow AWS services to access resources in other services to complete an action on your behalf. Service-linked roles appear in your IAM account and are owned by the service. An IAM administrator can view but not edit the permissions for service-linked roles.

Amazon WorkMail supports service-linked roles. For details about creating or managing Amazon WorkMail service-linked roles, see Using service-linked roles for Amazon WorkMail.

Service roles

This feature allows a service to assume a service role on your behalf. This role allows the service to access resources in other services to complete an action on your behalf. Service roles appear in your IAM account and are owned by the account. This means that an IAM administrator can change the permissions for this role. However, doing so might break the functionality of the service.

Amazon WorkMail supports service roles.