# How AWS Billing Conductor works with IAM
<a name="security_iam_service-with-iam"></a>

Before you use IAM to manage access to Billing Conductor, you should understand what IAM features are available to use with Billing Conductor. To get a high-level view of how Billing Conductor and other AWS services work with IAM, see [AWS Services That Work with IAM](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_aws-services-that-work-with-iam.html) in the *IAM User Guide*.

**Topics**
+ [

## Billing Conductor identity-based policies
](#security_iam_service-with-iam-id-based-policies)
+ [

## Billing Conductor resource-based policies
](#security_iam_service-with-iam-resource-based-policies)
+ [

## Access control lists (ACLs)
](#security_iam_service-with-iam-acls)
+ [

## Authorization based on Billing Conductor tags
](#security_iam_service-with-iam-tags)
+ [

## Billing Conductor IAM roles
](#security_iam_service-with-iam-roles)

## Billing Conductor identity-based policies
<a name="security_iam_service-with-iam-id-based-policies"></a>

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. Billing Conductor 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](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements.html) in the *IAM User Guide*.

### Actions
<a name="security_iam_service-with-iam-id-based-policies-actions"></a>

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

Policy actions in Billing Conductor use the following prefix before the action: `Billing Conductor:`. For example, to grant someone permission to run an Amazon EC2 instance with the Amazon EC2 `RunInstances` API operation, you include the `ec2:RunInstances` action in their policy. Policy statements must include either an `Action` or `NotAction` element. Billing Conductor 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": [
      "ec2:action1",
      "ec2:action2"
```

You can specify multiple actions using wildcards (\$1). For example, to specify all actions that begin with the word `Describe`, include the following action:

```
"Action": "ec2:Describe*"
```



To see a list of Billing Conductor actions, see [Actions Defined by AWS Billing Conductor](https://docs.aws.amazon.com/IAM/latest/UserGuide/list_awsbillingconductor.html#awsbillingconductor-actions-as-permissions) in the *IAM User Guide*.

### Resources
<a name="security_iam_service-with-iam-id-based-policies-resources"></a>

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. As a best practice, specify a resource using its [Amazon Resource Name (ARN)](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference-arns.html). For actions that don't support resource-level permissions, use a wildcard (\$1) to indicate that the statement applies to all resources.

```
"Resource": "*"
```



The Amazon EC2 instance resource has the following ARN:

```
arn:${Partition}:ec2:${Region}:${Account}:instance/${InstanceId}
```

For more information about the format of ARNs, see [Amazon Resource Names (ARNs) and AWS Service Namespaces](https://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html).

For example, to specify the `i-1234567890abcdef0` instance in your statement, use the following ARN:

```
"Resource": "arn:aws:ec2:us-east-1:123456789012:instance/i-1234567890abcdef0"
```

To specify all instances that belong to a specific account, use the wildcard (\$1):

```
"Resource": "arn:aws:ec2:us-east-1:123456789012:instance/*"
```

Some Billing Conductor actions, such as those for creating resources, cannot be performed on a specific resource. In those cases, you must use the wildcard (\$1).

```
"Resource": "*"
```

Many Amazon EC2 API actions involve multiple resources. For example, `AttachVolume` attaches an Amazon EBS volume to an instance, so an IAM user must have permissions to use the volume and the instance. To specify multiple resources in a single statement, separate the ARNs with commas. 

```
"Resource": [
      "resource1",
      "resource2"
```

To see a list of Billing Conductor resource types and their ARNs, see [Resources Defined by AWS Billing Conductor](https://docs.aws.amazon.com/IAM/latest/UserGuide/list_awsbillingconductor.html#awsbillingconductor-resources-for-iam-policies) in the *IAM User Guide*. To learn with which actions you can specify the ARN of each resource, see [Actions Defined by AWS Billing Conductor](https://docs.aws.amazon.com/IAM/latest/UserGuide/list_awsbillingconductor.html#awsbillingconductor-actions-as-permissions).

### Condition keys
<a name="security_iam_service-with-iam-id-based-policies-conditionkeys"></a>

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 `Condition` element specifies when statements execute based on defined criteria. You can create conditional expressions that use [condition operators](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_condition_operators.html), such as equals or less than, to match the condition in the policy with values in the request. To see all AWS global condition keys, see [AWS global condition context keys](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_condition-keys.html) in the *IAM User Guide*.

Billing Conductor defines its own set of condition keys and also supports using some global condition keys. To see all AWS global condition keys, see [AWS Global Condition Context Keys](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_condition-keys.html) in the *IAM User Guide*.



 All Amazon EC2 actions support the `aws:RequestedRegion` and `ec2:Region` condition keys. For more information, see [Example: Restricting Access to a Specific Region](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ExamplePolicies_EC2.html#iam-example-region). 

To see a list of Billing Conductor condition keys, see [Condition Keys for AWS Billing Conductor](https://docs.aws.amazon.com/IAM/latest/UserGuide/list_awsbillingconductor.html#awsbillingconductor-policy-keys) in the *IAM User Guide*. To learn with which actions and resources you can use a condition key, see [Actions Defined by AWS Billing Conductor](https://docs.aws.amazon.com/IAM/latest/UserGuide/list_awsbillingconductor.html#awsbillingconductor-actions-as-permissions).

### Examples
<a name="security_iam_service-with-iam-id-based-policies-examples"></a>



To view examples of Billing Conductor identity-based policies, see [AWS Billing Conductor identity-based policy examples](security_iam_id-based-policy-examples.md).

## Billing Conductor resource-based policies
<a name="security_iam_service-with-iam-resource-based-policies"></a>

Resource-based policies are JSON policy documents that specify what actions a specified principal can perform on the Billing Conductor resource and under what conditions. Amazon S3 supports resource-based permissions policies for Amazon S3 *buckets*. Resource-based policies let you grant usage permission to other accounts on a per-resource basis. You can also use a resource-based policy to allow an AWS service to access your Amazon S3 *buckets*.

To enable cross-account access, you can specify an entire account or IAM entities in another account as the [principal in a resource-based policy](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_principal.html). Adding a cross-account principal to a resource-based policy is only half of establishing the trust relationship. When the principal and the resource are in different AWS accounts, you must also grant the principal entity permission to access the resource. Grant permission by attaching an identity-based policy to the entity. However, if a resource-based policy grants access to a principal in the same account, no additional identity-based policy is required. For more information, see [How IAM Roles Differ from Resource-based Policies ](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_compare-resource-policies.html)in the *IAM User Guide*.

The Amazon S3 service supports only one type of resource-based policy called a **bucket* policy*, which is attached to a *bucket*. This policy defines which principal entities (accounts, users, roles, and federated users) can perform actions on the *Billing Conductor*.

### Examples
<a name="security_iam_service-with-iam-resource-based-policies-examples"></a>



To view examples of Billing Conductor resource-based policies, see [AWS Billing Conductor resource-based policy examples](security_iam_resource-based-policy-examples.md),

## Access control lists (ACLs)
<a name="security_iam_service-with-iam-acls"></a>

Access control lists (ACLs) are lists of grantees that you can attach to resources. They grant accounts permissions to access the resource to which they are attached. You can attach ACLs to an Amazon S3 *bucket* resource.

With Amazon S3 access control lists (ACLs), you can manage access to *bucket* resources. Each *bucket* has an ACL attached to it as a subresource. It defines which AWS accounts, IAM users or groups of users, or IAM roles are granted access and the type of access. When a request is received for a resource, AWS checks the corresponding ACL to verify that the requester has the necessary access permissions.

When you create a *bucket* resource, Amazon S3 creates a default ACL that grants the resource owner full control over the resource. In the following example *bucket* ACL, John Doe is listed as the owner of the *bucket* and is granted full control over that *bucket*. An ACL can have up to 100 grantees.

```
<?xml version="1.0" encoding="UTF-8"?>
<AccessControlPolicy xmlns="http://Billing Conductor.amazonaws.com/doc/2006-03-01/">
  <Owner>
    <ID>c1daexampleaaf850ea79cf0430f33d72579fd1611c97f7ded193374c0b163b6</ID>
    <DisplayName>john-doe</DisplayName>
  </Owner>
  <AccessControlList>
    <Grant>
      <Grantee xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
               xsi:type="Canonical User">
        <ID>c1daexampleaaf850ea79cf0430f33d72579fd1611c97f7ded193374c0b163b6</ID>
        <DisplayName>john-doe</DisplayName>
      </Grantee>
      <Permission>FULL_CONTROL</Permission>
    </Grant>
  </AccessControlList>
</AccessControlPolicy>
```

The ID field in the ACL is the AWS account canonical user ID. To learn how to view this ID in an account that you own, see [Finding an AWS Account Canonical User ID](https://docs.aws.amazon.com/general/latest/gr/acct-identifiers.html#FindingCanonicalId). 

## Authorization based on Billing Conductor tags
<a name="security_iam_service-with-iam-tags"></a>

You can attach tags to Billing Conductor resources or pass tags in a request to Billing Conductor. To control access based on tags, you provide tag information in the [condition element](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_condition.html) of a policy using the `Billing Conductor:ResourceTag/key-name`, `aws:RequestTag/key-name`, or `aws:TagKeys` condition keys.

## Billing Conductor IAM roles
<a name="security_iam_service-with-iam-roles"></a>

An [IAM role](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles.html) is an entity within your AWS account that has specific permissions.

### Using temporary credentials with Billing Conductor
<a name="security_iam_service-with-iam-roles-tempcreds"></a>

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](https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html) or [GetFederationToken](https://docs.aws.amazon.com/STS/latest/APIReference/API_GetFederationToken.html). 

Billing Conductor supports using temporary credentials. 

### Service-linked roles
<a name="security_iam_service-with-iam-roles-service-linked"></a>

[Service-linked roles](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_terms-and-concepts.html#iam-term-service-linked-role) 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.

### Service roles
<a name="security_iam_service-with-iam-roles-service"></a>

This feature allows a service to assume a [service role](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_terms-and-concepts.html#iam-term-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.

Billing Conductor supports service roles. 

### Choosing an IAM role in Billing Conductor
<a name="security_iam_service-with-iam-roles-choose"></a>

When you create a resource in Billing Conductor, you must choose a role to allow Billing Conductor to access Amazon EC2 on your behalf. If you have previously created a service role or service-linked role, then Billing Conductor provides you with a list of roles to choose from. It's important to choose a role that allows access to start and stop Amazon EC2 instances.