All posts by Ujjwal Pugalia

Now Use AWS IAM to Delete a Service-Linked Role When You No Longer Require an AWS Service to Perform Actions on Your Behalf

Post Syndicated from Ujjwal Pugalia original https://aws.amazon.com/blogs/security/now-use-aws-iam-to-delete-a-service-linked-role-when-you-no-longer-require-an-aws-service-to-perform-actions-on-your-behalf/

Earlier this year, AWS Identity and Access Management (IAM) introduced service-linked roles, which provide you an easy and secure way to delegate permissions to AWS services. Each service-linked role delegates permissions to an AWS service, which is called its linked service. Service-linked roles help with monitoring and auditing requirements by providing a transparent way to understand all actions performed on your behalf because AWS CloudTrail logs all actions performed by the linked service using service-linked roles. For information about which services support service-linked roles, see AWS Services That Work with IAM. Over time, more AWS services will support service-linked roles.

Today, IAM added support for the deletion of service-linked roles through the IAM console and the IAM API/CLI. This means you now can revoke permissions from the linked service to create and manage AWS resources in your account. When you delete a service-linked role, the linked service no longer has the permissions to perform actions on your behalf. To ensure your AWS services continue to function as expected when you delete a service-linked role, IAM validates that you no longer have resources that require the service-linked role to function properly. This prevents you from inadvertently revoking permissions required by an AWS service to manage your existing AWS resources and helps you maintain your resources in a consistent state. If there are any resources in your account that require the service-linked role, you will receive an error when you attempt to delete the service-linked role, and the service-linked role will remain in your account. If you do not have any resources that require the service-linked role, you can delete the service-linked role and IAM will remove the service-linked role from your account.

In this blog post, I show how to delete a service-linked role by using the IAM console. To learn more about how to delete service-linked roles by using the IAM API/CLI, see the DeleteServiceLinkedRole API documentation.

Note: The IAM console does not currently support service-linked role deletion for Amazon Lex, but you can delete your service-linked role by using the Amazon Lex console. To learn more, see Service Permissions.

How to delete a service-linked role by using the IAM console

If you no longer need to use an AWS service that uses a service-linked role, you can remove permissions from that service by deleting the service-linked role through the IAM console. To delete a service-linked role, you must have permissions for the iam:DeleteServiceLinkedRole action. For example, the following IAM policy grants the permission to delete service-linked roles used by Amazon Redshift. To learn more about working with IAM policies, see Working with Policies.

{ 
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "AllowDeletionOfServiceLinkedRolesForRedshift",
            "Effect": "Allow",
            "Action": ["iam:DeleteServiceLinkedRole"],
            "Resource": ["arn:aws:iam::*:role/aws-service-role/redshift.amazonaws.com/AWSServiceRoleForRedshift*"]
	 }
    ]
}

To delete a service-linked role by using the IAM console:

  1. Navigate to the IAM console and choose Roles from the navigation pane.

Screenshot of the Roles page in the IAM console

  1. Choose the service-linked role you want to delete and then choose Delete role. In this example, I choose the  AWSServiceRoleForRedshift service-linked role.

Screenshot of the AWSServiceRoleForRedshift service-linked role

  1. A dialog box asks you to confirm that you want to delete the service-linked role you have chosen. In the Last activity column, you can see when the AWS service last used the service-linked role, which tells you when the linked service last used the service-linked role to perform an action on your behalf. If you want to continue to delete the service-linked role, choose Yes, delete to delete the service-linked role.

Screenshot of the "Delete role" window

  1. IAM then checks whether you have any resources that require the service-linked role you are trying to delete. While IAM checks, you will see the status message, Deletion in progress, below the role name. Screenshot showing "Deletion in progress"
  1. If no resources require the service-linked role, IAM deletes the role from your account and displays a success message on the console.

Screenshot of the success message

  1. If there are AWS resources that require the service-linked role you are trying to delete, you will see the status message, Deletion failed, below the role name.

Screenshot showing the "Deletion failed"

  1. If you choose View details, you will see a message that explains the deletion failed because there are resources that use the service-linked role.
    Screenshot showing details about why the role deletion failed
  2. Choose View Resources to view the Amazon Resource Names (ARNs) of the first five resources that require the service-linked role. You can delete the service-linked role only after you delete all resources that require the service-linked role. In this example, only one resource requires the service-linked role.

Conclusion

Service-linked roles make it easier for you to delegate permissions to AWS services to create and manage AWS resources on your behalf and to understand all actions the service will perform on your behalf. If you no longer need to use an AWS service that uses a service-linked role, you can remove permissions from that service by deleting the service-linked role through the IAM console. However, before you delete a service-linked role, you must delete all the resources associated with that role to ensure that your resources remain in a consistent state.

If you have any questions, submit a comment in the “Comments” section below. If you need help working with service-linked roles, start a new thread on the IAM forum or contact AWS Support.

– Ujjwal

Greater Transparency into Actions AWS Services Perform on Your Behalf by Using AWS CloudTrail

Post Syndicated from Ujjwal Pugalia original https://aws.amazon.com/blogs/security/get-greater-transparency-into-actions-aws-services-perform-on-your-behalf-by-using-aws-cloudtrail/

To make managing your AWS account easier, some AWS services perform actions on your behalf, including the creation and management of AWS resources. For example, AWS Elastic Beanstalk automatically handles the deployment details of capacity provisioning, load balancing, auto-scaling, and application health monitoring. To make these AWS actions more transparent, AWS adds an AWS Identity and Access Management (IAM) service-linked roles to your account for each linked service you use. Service-linked roles let you view all actions an AWS service performs on your behalf by using AWS CloudTrail logs. This helps you monitor and audit the actions AWS services perform on your behalf. No additional actions are required from you and you can continue using AWS services the way you do today.

To learn more about which AWS services use service-linked roles and log actions on your behalf to CloudTrail, see AWS Services That Work with IAM. Over time, more AWS services will support service-linked roles. For more information about service-linked roles, see Role Terms and Concepts.

In this blog post, I demonstrate how to view CloudTrail logs so that you can more easily monitor and audit AWS services performing actions on your behalf. First, I show how AWS creates a service-linked role in your account automatically when you configure an AWS service that supports service-linked roles. Next, I show how you can view the policies of a service-linked role that grants an AWS service permission to perform actions on your behalf. Finally, I  use the configured AWS service to perform an action and show you how the action appears in your CloudTrail logs.

How AWS creates a service-linked role in your account automatically

I will use Amazon Lex as the AWS service that performs actions on your behalf for this post. You can use Amazon Lex to create chatbots that allow for highly engaging conversational experiences through voice and text. You also can use chatbots on mobile devices, web browsers, and popular chat platform channels such as Slack. Amazon Lex uses Amazon Polly on your behalf to synthesize speech that sounds like a human voice.

Amazon Lex uses two IAM service-linked roles:

  • AWSServiceRoleForLexBots — Amazon Lex uses this service-linked role to invoke Amazon Polly to synthesize speech responses for your chatbot.
  • AWSServiceRoleForLexChannels — Amazon Lex uses this service-linked role to post text to your chatbot when managing channels such as Slack.

You don’t need to create either of these roles manually. When you create your first chatbot using the Amazon Lex console, Amazon Lex creates the AWSServiceRoleForLexBots role for you. When you first associate a chatbot with a messaging channel, Amazon Lex creates the AWSServiceRoleForLexChannels role in your account.

1. Start configuring the AWS service that supports service-linked roles

Navigate to the Amazon Lex console, and choose Get Started to navigate to the Create your Lex bot page. For this example, I choose a sample chatbot called OrderFlowers. To learn how to create a custom chatbot, see Create a Custom Amazon Lex Bot.

Screenshot of making the choice to create an OrderFlowers chatbot

2. Complete the configuration for the AWS service

When you scroll down, you will see the settings for the OrderFlowers chatbot. Notice the field for the IAM role with the value, AWSServiceRoleForLexBots. This service-linked role is “Automatically created on your behalf.” After you have entered all details, choose Create to build your sample chatbot.

Screenshot of the automatically created service-linked role

AWS has created the AWSServiceRoleForLexBots service-linked role in your account. I will return to using the chatbot later in this post when I discuss how Amazon Lex performs actions on your behalf and how CloudTrail logs these actions. First, I will show how you can view the permissions for the AWSServiceRoleForLexBots service-linked role by using the IAM console.

How to view actions in the IAM console that AWS services perform on your behalf

When you configure an AWS service that supports service-linked roles, AWS creates a service-linked role in your account automatically. You can view the service-linked role by using the IAM console.

1. View the AWSServiceRoleForLexBots service-linked role on the IAM console

Go to the IAM console, and choose AWSServiceRoleForLexBots on the Roles page. You can confirm that this role is a service-linked role by viewing the Trusted entities column.

Screenshot of the service-linked role

2.View the trusted entities that can assume the AWSServiceRoleForLexBots service-linked role

Choose the Trust relationships tab on the AWSServiceRoleForLexBots role page. You can view the trusted entities that can assume the AWSServiceRoleForLexBots service-linked role to perform actions on your behalf. In this example, the trusted entity is lex.amazonaws.com.

Screenshot of the trusted entities that can assume the service-linked role

3. View the policy attached to the AWSServiceRoleForLexBots service-linked role

Choose AmazonLexBotPolicy on the Permissions tab to view the policy attached to the AWSServiceRoleForLexBots service-linked role. You can view the policy summary to see that AmazonLexBotPolicy grants permission to Amazon Lex to use Amazon Polly.

Screenshot showing that AmazonLexBotPolicy grants permission to Amazon Lex to use Amazon Polly

4. View the actions that the service-linked role grants permissions to use

Choose Polly to view the action, SynthesizeSpeech, that the AmazonLexBotPolicy grants permission to Amazon Lex to perform on your behalf. Amazon Lex uses this permission to synthesize speech responses for your chatbot. I show later in this post how you can monitor this SynthesizeSpeech action in your CloudTrail logs.

Screenshot showing the the action, SynthesizeSpeech, that the AmazonLexBotPolicy grants permission to Amazon Lex to perform on your behalf

Now that I know the trusted entity and the policy attached to the service-linked role, let’s go back to the chatbot I created earlier and see how CloudTrail logs the actions that Amazon Lex performs on my behalf.

How to use CloudTrail to view actions that AWS services perform on your behalf

As discussed already, I created an OrderFlowers chatbot on the Amazon Lex console. I will use the chatbot and display how the AWSServiceRoleForLexBots service-linked role helps me track actions in CloudTrail. First, though, I must have an active CloudTrail trail created that stores the logs in an Amazon S3 bucket. I will use a trail called TestTrail and an S3 bucket called account-ids-slr.

1. Use the Amazon Lex chatbot via the Amazon Lex console

In Step 2 in the first section of this post, when I chose Create, Amazon Lex built the OrderFlowers chatbot. After the chatbot was built, the right pane showed that a Test Bot was created. Now, I choose the microphone symbol in the right pane and provide voice input to test the OrderFlowers chatbot. In this example, I tell the chatbot, “I would like to order some flowers.” The bot replies to me by asking, “What type of flowers would you like to order?”

Screenshot of voice input to test the OrderFlowers chatbot

When the chatbot replies using voice, Amazon Lex uses Amazon Polly to synthesize speech from text to voice. Amazon Lex assumes the AWSServiceRoleForLexBots service-linked role to perform the SynthesizeSpeech action.

2. Check CloudTrail to view actions performed on your behalf

Now that I have created the chatbot, let’s see which actions were logged in CloudTrail. Choose CloudTrail from the Services drop-down menu to reach the CloudTrail console. Choose Trails and choose the S3 bucket in which you are storing your CloudTrail logs.

Screenshot of the TestTrail trail

In the S3 bucket, you will find log entries for the SynthesizeSpeech event. This means that CloudTrail logged the action when Amazon Lex assumed the AWSServiceRoleForLexBots service-linked role to invoke Amazon Polly to synthesize speech responses for your chatbot. You can monitor and audit this invocation, and it provides you with transparency into Amazon Polly’s SynthesizeSpeech action that Amazon Lex invoked on your behalf. The applicable CloudTrail log section follows and I have emphasized the key lines.

{  
         "eventVersion":"1.05",
         "userIdentity":{  
           "type":"AssumedRole",
            "principalId":"{principal-id}:OrderFlowers",
            "arn":"arn:aws:sts::{account-id}:assumed-role/AWSServiceRoleForLexBots/OrderFlowers",
            "accountId":"{account-id}",
            "accessKeyId":"{access-key-id}",
            "sessionContext":{  
               "attributes":{  
                  "mfaAuthenticated":"false",
                  "creationDate":"2017-09-17T17:30:05Z"
               },
               "sessionIssuer":{  
                  "type":"Role",
                  "principalId":"{principal-id}",
                  "arn":"arn:aws:iam:: {account-id}:role/aws-service-role/lex.amazonaws.com/AWSServiceRoleForLexBots",
                  "accountId":"{account-id",
                  "userName":"AWSServiceRoleForLexBots"
               }
            },
            "invokedBy":"lex.amazonaws.com"
         },
         "eventTime":"2017-09-17T17:30:05Z",
         "eventSource":"polly.amazonaws.com",
         "eventName":"SynthesizeSpeech",
         "awsRegion":"us-east-1",
         "sourceIPAddress":"lex.amazonaws.com",
         "userAgent":"lex.amazonaws.com",
         "requestParameters":{  
            "outputFormat":"mp3",
            "textType":"text",
            "voiceId":"Salli",
            "text":"**********"
         },
         "responseElements":{  
            "requestCharacters":45,
            "contentType":"audio/mpeg"
         },
         "requestID":"{request-id}",
         "eventID":"{event-id}",
         "eventType":"AwsApiCall",
         "recipientAccountId":"{account-id}"
      }

Conclusion

Service-linked roles make it easier for you to track and view actions that linked AWS services perform on your behalf by using CloudTrail. When an AWS service supports service-linked roles to enable this additional logging, you will see a service-linked role added to your account.

If you have comments about this post, submit a comment in the “Comments” section below. If you have questions about working with service-linked roles, start a new thread on the IAM forum or contact AWS Support.

– Ujjwal