security
AWS SSO Tutorial with Google Workspace (Gsuite) as an IdP Step-by-Step
Mike Elsmore •
AWS SSO and AWS Organization were released around 2017 and are probably the best way to manage AWS access at scale.
"AWS Single Sign-On (SSO) is a cloud SSO service that makes it easy to centrally manage SSO access to multiple AWS accounts and business applications. It enables users to sign in to an AWS IAM user with their existing corporate credentials and access all of their assigned accounts and applications from one place." Quote From AWS SSO page
This is a huge security and operational win, some highlights:
- No need to rotate another new password in AWS IAM
- 2FA is already managed at your IdP (Google Workspace (G Suite)/Okta/AzureAD) level
- When a user is leaving an organization he is automatically removed access from the organization
- Easily automate the provisioning of AWS access when a user joins an organisation or department
In this article we, will go through a step-by-step guide to set-up AWS SSO with Google Workspace (previously G Suite) as an IdP. If you are using Google Workspace and use it as your central directory, this is the guide for you.
Prerequisite #
You should have the AWS Organization (If you are not using it, This service combined with AWS SSO is a real game changer) set-up.
You need to sign up from the main account (also called "management account" ) and with enough permissions (usually Administrator permissions).
You will also need to make sure that you have access to the Google Workspace Admin and the relevant permissions to manage it.
Setting up AWS #
Now that you have all the relevant permissions, everything is ready to configure for AWS SSO. Here is the step by step to set it all up:
- Once on the service page, click the
Enable AWS SSO
button to start the service. This will take a few moments to complete. - Now that SSO is enabled, we need to change from the AWS directory to using an external provider. Select
Choose your identity source
. - Within the Settings page, select
Change
under theIdentity source
section. - Now we can change from the AWS SSO directory to an Active Directory (not what we need), or an
External identity provider
which is what we need to configure Google Workspace as the provider. - After you have selected
External identity provider
, scroll down toService provider metadata
and clickShow individual metadata values
. - You should now be presented with three fields that you can use to configure the next step on Google Workspace in the Google Admin console.
- Don't close this screen, you will need it shortly after you have done the next section.
Google Workspace SAML setup #
With the SSO URLs for our AWS organization, we can go to our Google Workspace Admin console and configure it.
- When inside the Google Workspace Admin console, go to the
Web and mobile apps
settings. You can find this in the left-hand navigation menu underApps
. - Then select
Add App
from the top navigation, thenAdd custom SAML app
. - Add an
App name
for the integration, I'm usingAWS SSO
to make it easier to find later. - We suggest you download the Google IdP metadata ready to put it back into AWS, this is under
Option 1: Download IdP metadata
. - Now to add the AWS SSO URLs from earlier to configure Google Workspace to point to the correct location. The mapping of data is:
- For ACS URL, enter the AWS SSO ACS URL.
- For Entity ID, enter the AWS SSO Issue URL.
- For Start URL, leave the field blank.
- For Name ID format, choose EMAIL.
- For Name ID, choose Basic Information > Primary email.
- We don't need to apply anything to the
Attribute mapping
settings, so you can just clickFINISH
to move forward. - Once that's saved, it is time to enable it for everyone. In the
User access
section, open the settings by selecting the karat in the top right corner. - Now that you're in the Service status screen, select
ON for everyone
andSAVE
. This will enable the service and allow you to manage who can have access to AWS, but to configure what they can access you need to do that in AWS SSO as Google Workspace is unaware of all the possible options.
Adding Google Workspace configuration to AWS SSO #
Now that the AWS SSO service is enabled, and the Google Workspace SAML app exists, it's time to make them talk to each other.
- Go back to the
Change identity source
screen in AWS SSO. Scroll to the bottom and add theGoogleIDPMetadata.xml
file you downloaded a few moments ago, then clickNext: Review
. - To confirm this new identity source, you will need to type
ACCEPT
into the field under the warnings and then selectChange identity source
. - And now you are done with configuring the SSO and SAML connection between AWS SSO and Google Workspace. However, you aren't quite done as you need to configure the user provisioning at this point.
Setting up Users and Permissions #
As of writing this, you can't automatically sync users between AWS and Google (this is being worked on over at OpenID) so we are limited to two options; manually creating the user (which we will go through) and using https://github.com/awslabs/ssosync to automate the process.
To manually add users, you will want to follow these instructions.
- Go to
Users
in the sidebar of theAWS SSO
service. Then selectAdd user
. - Use the primary Google Workplace email address as the
Username
as well as theEmail address
, and fill the other fields accordingly. Then hitNext: Groups
to save. - As part of this process, we aren't going to be adding groups so we can skip these phases by selecting
Add user
in the bottom right. - The user now needs to be associated with an AWS account. So select
AWS accounts
from the left navigation, select the checkbox next to the user, and clickAssign users
to attach them to the account. - On the next screen select the user again so that we can move on to permissions by clicking
Next: Permissions sets
. - As we haven’t configured and permission sets before we will have to do that now by clicking
Create new permission set
. - We will be using
Use an existing job function policy
, these are like AWS managed policies that you will be aware of if you have configured permissions inside AWS previously. NowNext: Details
to select the policy. - From here you can select the policy you want to assign, I'll be using
AdministratorAccess
as this is for myself. But you could usePowerUserAccess
as this would allow the user to build whatever they want, but not mess with other users and groups. Then clickNext: Tags
to apply this to the user. - Tags are optional, but they are advised for auditing and search at a later point. But I don't need them so we select
Next: Review
to move forward. - A quick once over to make sure everything is set correctly, then we can click
Create
to do so. - Back to our
Assign Users
screen, we can click the refresh icon to view our permission sets. From here we select the checkbox for the permissions set we want for the user, then selectFinish
to apply it. - It'll take a moment to provision, but you should get a Complete screen saying you are done.
And we are done, now the user can authenticate and log in from Google Workplace using the handy link in the
Google apps
selector.Summary #
By now you should have AWS SSO configured with Google Workspace as an IdP and you can manage access & permissions to your AWS in the AWS SSO service.