Skip to content

Commit

Permalink
feat: allow all sts options for roles assumed by the cli (#31089)
Browse files Browse the repository at this point in the history
Allow passing [all STS options](https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html#API_AssumeRole_RequestParameters) to assume role configuration for various CDK roles. 

> The following PR description focuses on Session Tags because it was originally the only option we wanted to add support to. After some thought, we decided to allow all available STS options via a transparent pass-through.

### Prerequisites

- cdklabs/cloud-assembly-schema#33
- cdklabs/cdk-assets#40

### Issue # (if applicable)

Closes #26157 
Fixes #22535

### Reason for this change

Enabling [ABAC](https://docs.aws.amazon.com/IAM/latest/UserGuide/introduction_attribute-based-access-control.html) via STS session tags. From the [AWS docs](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_session-tags.html):


> _“Session Tags are key-value pair attributes that you pass when you assume an IAM role or federate a user in AWS STS. You do this by making an AWS CLI or AWS API request through AWS STS or through your identity provider (IdP). When you use AWS STS to request temporary security credentials, you generate a session. Sessions expire and have [credentials](https://docs.aws.amazon.com/STS/latest/APIReference/API_Credentials.html), such as an access key pair and a session token. When you use the session credentials to make a subsequent request, the [request context](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_condition.html#AccessPolicyLanguage_RequestContext) includes the [aws:PrincipalTag](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_condition-keys.html#condition-keys-principaltag) context key. You can use the aws:PrincipalTag key in the Condition element of your policies to allow or deny access based on those tags”_

### Description of changes

The CDK creates [4 IAM roles](https://docs.aws.amazon.com/cdk/v2/guide/bootstrapping-env.html#bootstrapping-env-roles) during bootstrap. It then assumes these roles at various phases of the deployment.

- [DeploymentActionRole](https://github.com/aws/aws-cdk/blob/v2.154.1/packages/aws-cdk/lib/api/bootstrap/bootstrap-template.yaml#L429): Assumed when invoking CloudFormation operations such as _Deploy_ and _DescribeStackEvents_.
- [FilePublishingRole](https://github.com/aws/aws-cdk/blob/v2.154.1/packages/aws-cdk/lib/api/bootstrap/bootstrap-template.yaml#L275): Assumed when file assets are uploaded to the bootstrap bucket.
- [ImagePublishingRole](https://github.com/aws/aws-cdk/blob/v2.154.1/packages/aws-cdk/lib/api/bootstrap/bootstrap-template.yaml#L298): Assumed when docker images are published to the bootstrap ECR registry.
- [LookupRole](https://github.com/aws/aws-cdk/blob/v2.154.1/packages/aws-cdk/lib/api/bootstrap/bootstrap-template.yaml#L321): Assumed while performing context lookups.

Each of these roles should be assumable with their own specific session tags, as they server different purposes.

> Note: The [CloudFormationExecutionRole](https://github.com/aws/aws-cdk/blob/v2.154.1/packages/aws-cdk/lib/api/bootstrap/bootstrap-template.yaml#L536) is also created during bootstrap, but the CLI never assumes it, therefore it doesn't need session tags support.

Session tags for each role will be configurable via synthesizer properties (similarly to how `externalId` is [exposed](#15604)) both for the `DefaultStackSynthesizer`, and for a custom synthesizer extending the `StackSynthesizer` class. The new properties will propagate down and will eventually be written to the cloud assembly.

#### `+ manifest.json`

```json
{
  "version": "36.0.0",
  "artifacts": {
    "MyStack.assets": {
      "type": "cdk:asset-manifest",
      "properties": {
        "file": "SeshTagsManifestStack.assets.json",
        "requiresBootstrapStackVersion": 6,
        "bootstrapStackVersionSsmParameter": "/cdk-bootstrap/hnb659fds/version"
      }
    },
    "MyStack": {
      "type": "aws:cloudformation:stack",
      "environment": "aws://unknown-account/unknown-region",
      "properties": {
        "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-deploy-role-${AWS::AccountId}-${AWS::Region}",
          "assumeRoleAdditionalOptions": {
            "Tags": < deployRoleSessionTags > 
          }
        "lookupRole": {
          "arn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-lookup-role-${AWS::AccountId}-${AWS::Region}",
          "requiresBootstrapStackVersion": 8,
          "bootstrapStackVersionSsmParameter": "/cdk-bootstrap/hnb659fds/version"
          "assumeRoleAdditionalOptions": {
            "Tags": < lookupRoleSessionTags > 
          }
        }
      },
```

#### `+ assets.json`

```json
{
  "version": "36.0.0",
  "files": {
    "9ebfd704f02f99b2711998e6435822b0dbed6e80dcac7e75f339fe894861ac20": {
      "source": {
        "path": "mystack.template.json",
        "packaging": "file"
      },
      "destinations": {
        "current_account-current_region": {
          "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-file-publishing-role-${AWS::AccountId}-${AWS::Region}"
          "assumeRoleAdditionalOptions": {
             "Tags": < fileAssetPublishingRoleSessionTags >
           }
        }
      }
    }
  },
  "dockerImages": {
    "dockerHash": {
      "source": {
        "directory": "."
      },
      "destinations": {
        "current_account-current_region": {
          "assumeRoleArn": "arn:${AWS::Partition}:iam::${AWS::AccountId}:role/cdk-hnb659fds-image-publishing-role-${AWS::AccountId}-${AWS::Region}"
          "assumeRoleAdditionalOptions": {
            "Tags": < imageAssetPublishingRoleSessionTags >
          }
        }
      }
    }
  }
}
```

### Description of how you validated changes

- CLI integration tests.
- CLI and framework unit tests.

### Checklist
- [X] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*
  • Loading branch information
sumupitchayan authored Sep 23, 2024
1 parent 9952c92 commit 5e95ba2
Show file tree
Hide file tree
Showing 31 changed files with 2,112 additions and 1,482 deletions.
10 changes: 10 additions & 0 deletions packages/@aws-cdk-testing/cli-integ/lib/with-cdk-app.ts
Original file line number Diff line number Diff line change
Expand Up @@ -233,6 +233,13 @@ export async function cloneDirectory(source: string, target: string, output?: No
}

interface CommonCdkBootstrapCommandOptions {
/**
* Path to a custom bootstrap template.
*
* @default - the default CDK bootstrap template.
*/
readonly bootstrapTemplate?: string;

readonly toolkitStackName: string;

/**
Expand Down Expand Up @@ -422,6 +429,9 @@ export class TestFixture extends ShellHelper {
if (options.usePreviousParameters === false) {
args.push('--no-previous-parameters');
}
if (options.bootstrapTemplate) {
args.push('--template', options.bootstrapTemplate);
}

return this.cdk(args, {
...options.cliOptions,
Expand Down
Loading

0 comments on commit 5e95ba2

Please sign in to comment.