How EC2 Image Builder works with IAM - EC2 Image Builder

How EC2 Image Builder works with IAM

Before you use IAM to manage access to Image Builder, learn what IAM features are available to use with Image Builder.

To get a high-level view of how Image Builder and other AWS services work with most IAM features, see AWS services that work with IAM in the IAM User Guide.

Identity-based policies for Image Builder

Supports identity-based policies

Yes

Identity-based policies are JSON permissions policy documents that you can attach to an identity, such as an IAM user, group of users, or role. These policies control what actions users and roles can perform, on which resources, and under what conditions. To learn how to create an identity-based policy, see Creating IAM policies in the IAM User Guide.

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. You can't specify the principal in an identity-based policy because it applies to the user or role to which it is attached. To learn about all of the elements that you can use in a JSON policy, see IAM JSON policy elements reference in the IAM User Guide.

Identity-based policy examples for Image Builder

To view examples of Image Builder identity-based policies, see Image Builder identity-based policies.

Resource-based policies within Image Builder

Supports resource-based policies

Yes

Resource-based policies are JSON policy documents that you attach to a resource. Examples of resource-based policies are IAM role trust policies and Amazon S3 bucket policies. In services that support resource-based policies, service administrators can use them to control access to a specific resource. For the resource where the policy is attached, the policy defines what actions a specified principal can perform on that resource and under what conditions. You must specify a principal in a resource-based policy. Principals can include accounts, users, roles, federated users, or AWS services.

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. 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, an IAM administrator in the trusted account must also grant the principal entity (user or role) permission to access the resource. They 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 in the IAM User Guide.

Policy actions for Image Builder

Supports policy actions

Yes

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.

To see a list of Image Builder actions, see Actions defined by EC2 Image Builder in the Service Authorization Reference.

Policy actions in Image Builder use the following prefix before the action:

imagebuilder

To specify multiple actions in a single statement, separate them with commas.

"Action": [ "imagebuilder:action1", "imagebuilder:action2" ]

To view examples of Image Builder identity-based policies, see Image Builder identity-based policies.

Policy resources for Image Builder

Supports policy resources

Yes

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": "*"

To see a list of Image Builder resource types and their ARNs, see Resources defined by EC2 Image Builder in the Service Authorization Reference. To learn with which actions you can specify the ARN of each resource, see Actions defined by EC2 Image Builder.

To view examples of Image Builder identity-based policies, see Image Builder identity-based policies.

Policy condition keys for Image Builder

Supports service-specific policy condition keys

Yes

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 (or Condition block) lets you specify conditions in which a statement is in effect. The Condition element is optional. You can create conditional expressions that use condition operators, such as equals or less than, to match the condition in the policy with values in the request.

If you specify multiple Condition elements in a statement, or multiple keys in a single Condition element, AWS evaluates them using a logical AND operation. If you specify multiple values for a single condition key, AWS evaluates the condition using a logical OR operation. All of the conditions must be met before the statement's permissions are granted.

You can also use placeholder variables when you specify conditions. For example, you can grant an IAM user permission to access a resource only if it is tagged with their IAM user name. For more information, see IAM policy elements: variables and tags in the IAM User Guide.

AWS supports global condition keys and service-specific condition keys. To see all AWS global condition keys, see AWS global condition context keys in the IAM User Guide.

To see a list of Image Builder condition keys, see Condition keys for EC2 Image Builder in the Service Authorization Reference. To learn with which actions and resources you can use a condition key, see Actions defined by EC2 Image Builder.

To view examples of Image Builder identity-based policies, see Image Builder identity-based policies.

ACLs in Image Builder

Supports ACLs

No

Access control lists (ACLs) control which principals (account members, users, or roles) have permissions to access a resource. ACLs are similar to resource-based policies, although they do not use the JSON policy document format.

ABAC with Image Builder

Supports ABAC (tags in policies)

Partial

Attribute-based access control (ABAC) is an authorization strategy that defines permissions based on attributes. In AWS, these attributes are called tags. You can attach tags to IAM entities (users or roles) and to many AWS resources. Tagging entities and resources is the first step of ABAC. Then you design ABAC policies to allow operations when the principal's tag matches the tag on the resource that they are trying to access.

ABAC is helpful in environments that are growing rapidly and helps with situations where policy management becomes cumbersome.

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.

If a service supports all three condition keys for every resource type, then the value is Yes for the service. If a service supports all three condition keys for only some resource types, then the value is Partial.

For more information about ABAC, see What is ABAC? in the IAM User Guide. To view a tutorial with steps for setting up ABAC, see Use attribute-based access control (ABAC) in the IAM User Guide.

Using temporary credentials with Image Builder

Supports temporary credentials

Yes

Some AWS services don't work when you sign in using temporary credentials. For additional information, including which AWS services work with temporary credentials, see AWS services that work with IAM in the IAM User Guide.

You are using temporary credentials if you sign in to the AWS Management Console using any method except a user name and password. For example, when you access AWS using your company's single sign-on (SSO) link, that process automatically creates temporary credentials. You also automatically create temporary credentials when you sign in to the console as a user and then switch roles. For more information about switching roles, see Switching to a role (console) in the IAM User Guide.

You can manually create temporary credentials using the AWS CLI or AWS API. You can then use those temporary credentials to access AWS. AWS recommends that you dynamically generate temporary credentials instead of using long-term access keys. For more information, see Temporary security credentials in IAM.

Cross-service principal permissions for Image Builder

Supports forward access sessions (FAS)

Yes

When you use an IAM user or role to perform actions in AWS, you are considered a principal. When you use some services, you might perform an action that then initiates another action in a different service. FAS uses the permissions of the principal calling an AWS service, combined with the requesting AWS service to make requests to downstream services. FAS requests are only made when a service receives a request that requires interactions with other AWS services or resources to complete. In this case, you must have permissions to perform both actions. For policy details when making FAS requests, see Forward access sessions.

Service roles for Image Builder

Supports service roles

Yes

A service role is an IAM role that a service assumes to perform actions on your behalf. An IAM administrator can create, modify, and delete a service role from within IAM. For more information, see Creating a role to delegate permissions to an AWS service in the IAM User Guide.

Warning

Changing the permissions for a service role might break Image Builder functionality. Edit service roles only when Image Builder provides guidance to do so.

Service-linked roles for Image Builder

Supports service-linked roles

No

A service-linked role is a type of service role that is linked to an AWS service. The service can assume the role to perform an action on your behalf. Service-linked roles appear in your AWS account and are owned by the service. An IAM administrator can view, but not edit the permissions for service-linked roles.

For details about the Image Builder service-linked role, see Using service-linked roles for EC2 Image Builder.

Image Builder identity-based policies

With IAM identity-based policies, you can specify allowed or denied actions and resources, and also the conditions under which actions are allowed or denied. Image Builder supports specific actions, resources, and condition keys. For information about all of the elements that you use in a JSON policy, see Actions, Resources, and Condition Keys for Amazon EC2 Image Builder in the IAM User Guide.

Actions

Policy actions in Image Builder use the following prefix before the action: imagebuilder:. Policy statements must include either an Action or NotAction element. Image Builder 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": [ "imagebuilder:action1", "imagebuilder:action2"

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

"Action": "imagebuilder:List*"

To see a list of Image Builder actions, see Actions, Resources, and Condition Keys for AWS services in the IAM User Guide.

Managing access using policies

For detailed information about how to manage access in AWS by creating policies and attaching them to IAM identities or AWS resources, see Policies and Permissions in the IAM User Guide.

The IAM role that you associate with your instance profile must have permissions to run the build and test components included in your image. The following IAM role policies must be attached to the IAM role that is associated with the instance profile:

  • EC2InstanceProfileForImageBuilder

  • EC2InstanceProfileForImageBuilderECRContainerBuilds

  • AmazonSSMManagedInstanceCore

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": "*"

The Image Builder instance resource has the following Amazon Resource Name (ARN).

arn:aws:imagebuilder:region:account-id:resource:resource-id

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

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

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

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

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

Some Image Builder actions, such as those for creating resources, cannot be performed on a specific resource. In those cases, you must use the wildcard (*).

"Resource": "*"

Many EC2 Image Builder API actions involve multiple resources. To specify multiple resources in a single statement, separate the ARNs with commas.

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

Condition keys

Image Builder provides service-specific condition keys and supports using some global condition keys. To see all AWS global condition keys, see AWS Global Condition Context Keys in the IAM User Guide. The following service-specific condition keys are provided.

imagebuilder:CreatedResourceTagKeys

Works with string operators.

Use this key to filter access by the presence of tag keys in the request. This allows you to manage the resources that Image Builder creates.

Availability – This key is available to only the CreateInfrastrucutreConfiguration and UpdateInfrastructureConfiguration APIs.

imagebuilder:CreatedResourceTag/<key>

Works with string operators.

Use this key to filter access by the tag key-value pairs that are attached to the resource that Image Builder created. This allows you to manage Image Builder resources through defined tags.

Availability – This key is available to only the CreateInfrastrucutreConfiguration and UpdateInfrastructureConfiguration APIs.

imagebuilder:Ec2MetadataHttpTokens

Works with string operators.

Use this key to filter access by the EC2 Instance Metadata HTTP Token Requirement specified in the request.

This value for this key can be either optional or required.

Availability – This key is available to only the CreateInfrastrucutreConfiguration and UpdateInfrastructureConfiguration APIs.

imagebuilder:StatusTopicArn

Works with string operators.

Use this key to filter access by the SNS Topic ARN in the request to which terminal state notifications will be published.

Availability – This key is available to only the CreateInfrastrucutreConfiguration and UpdateInfrastructureConfiguration APIs.

Examples

To view examples of Image Builder identity-based policies, see EC2 Image Builder identity-based policies.

Image Builder resource-based policies

Resource-based policies specify what actions a specified principal can perform on the Image Builder resource and under what conditions. Image Builder supports resource-based permissions policies for components, images, and image recipes. 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 components, images, and image recipes.

For information about how to attach a resource-based policy to a component, image, or image recipe, see Share EC2 Image Builder resources.

Note

When you update a resource policy using Image Builder, the update will appear in the RAM console.

Authorization based on Image Builder tags

You can attach tags to Image Builder resources or pass tags in a request to Image Builder. To control access based on tags, you provide tag information in the condition element of a policy using the imagebuilder:ResourceTag/key-name, aws:RequestTag/key-name, or aws:TagKeys condition keys. For more information about tagging Image Builder resources, see Tag a resource (AWS CLI).

Image Builder IAM roles

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

Using temporary credentials with Image Builder

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.

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. A user with administrative access can view but not edit the permissions for service-linked roles.

Image Builder supports service-linked roles. For information about creating or managing Image Builder service-linked roles, see Using service-linked roles for EC2 Image Builder.

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 user with administrative access can change the permissions for this role. However, doing so might break the functionality of the service.