Protecting Okta App Sign-In with SGNL

Introduction

Protected Systems are applications, services, or infrastructure that you want to protect with SGNL. In this guide, we’ll describe how to achieve fine-grained access control at sign-in time with Okta and SGNL, enabling the right amount of access to applications and infrastructure connected to Okta. If you’d like to learn more about whether fine-grained Sign-In Policies with Okta and SGNL is right for your enterprise, visit our Securing AWS Blog or watch the video below to learn more.

With this integration, Okta need not know about the policies, systems of record, or any of the data in SGNL - it simply needs to pass to SGNL:

  • Who/What is requesting the access (The Principal)
  • (Optional) What is attempting to be accessed (The Asset)
  • (Optional) What operation is being attempted on the asset (The Action)
  • An access token that ensures the Protected System is a legitimate caller into SGNL

Prerequisites

  • An Okta Tenant
  • A SGNL Client
  • A SGNL User Account with Admin privileges
  • At least 1 Okta system of record integrated to SGNL, containing principals and (optionally) assets that will be evaluated in access evaluations
  • (Optional) 1 or more policies that you want assigned to the integration

Creating a Protected System in SGNL

  1. Log-In to your SGNL Client with an Admin Account
  2. From the left navigation pane, select Protected Systems and Add, or simply click Add from the SGNL Dashboard
  3. Select ‘Okta’ from the Identity Providers category in the list of integrations
  4. Give your integration a descriptive display name and description
  5. Specify the Default Policy to be applied to your App
    • Allow: If no policies provide a decision for an access request, SGNL will respond to the access request with an Allow decision
    • Deny: If no policies provide a decision for an access request, SGNL will respond to the access request with a Deny decision
  6. Next, you’ll need to configure which identifier Okta is using to describe your user/principal
    • This is likely your Okta user’s email address or login name. This should be in the format of the Principal ID of the user that will request access to the Protected System.
    • e.g. If an Okta user will be requesting access to this Protected System with the Principal ID as their email address, the principal identifier should be the Okta email address.
  7. You’ll also need to define the identifiers for the types of Assets that you are looking to protect
    • This might be app identifiers sourced directly from Okta, or something more granular within one of your other Systems of Record
  8. Once configured, click Continue to save your configuration and move on to other configuration steps

Configuring Authentication

  1. Authentication ensures that only authorized systems can make requests into SGNL, as well as verifying the identity of an integration in order to effectively evaluate Policies - to access Authentication settings, open your AWS protected system and select the Authentication tab

    SGNL - Authentication

  2. Click Generate Token

  3. Give your token a descriptive name so that you know how it’s being used in the future and click to Generate Token

    SGNL - Generate Token

  4. On the next screen, copy the token - this will be used by Okta to make access requests to SGNL using the SGNL Access Service API

    Note: The value of this token is not available again after this screen, so ensure you securely store it for steps later in this guide

    SGNL - Token

Integrating Okta Hooks with SGNL

Integrating SGNL with Okta, for the purposes of securing AWS or any Application, relies on Okta Inline Hooks. Okta Inline Hooks enable Okta to make an outbound request that can be routed to SGNL, in order to determine whether a user should have access to a specific application at that point in time, or what roles, claims, or tags to include in their SAML assertion

A simple example of this in action is using Okta Hooks to ask whether a user can access a specific customer’s data in AWS for a given session. In this scenario, SGNL Customers have found that PrincipalTags offer the greatest level of flexibility and dyamism, when combined with existing AWS roles, to dynamically specify an individual principal’s (user, service, robot, etc) permissions for a given session.

AWS provides the flexibility to enable Principal Tags to be used directly in conjunction with other policies that might already exist in AWS, and enables interleaving the tag directly into a resource name.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "s3:*",
            "Resource": "arn:aws:s3:::sensitive-prod-${aws:PrincipalTag/customerId}*"
        },
      ...
    ]
}

To get the appropriate set of access for a given session (and consequently the necessary tag), an inline hook is routed to SGNL at authentication time. The hook specifies the Customer ID for which the user is requesting access.

SGNL’s Access Service responds with a determination whether the acess to a specific customer is allowed for a given session:

{
    "decisions": [
        {
            "action": "access",
            "assetId": "{{customerId}}",
            "decision": "Allow"
        }
    ],
    "evaluationDuration": 8,
    "issuedAt": "2023-06-22T23:49:32.087875656Z",
    "principalId": "alice.wu@sgnl.ai"
}

If Access is Allowed, the Customer’s ID is packaged into the Okta SAML Assertion as a PrincipalTag and then the user is redirected to AWS to be signed in. At policy evaluation time, AWS inspects the Principal Tag and appropriate policy, determining whether the principal should be allowed to access a given resource.

At this point, it’s likely that all decisions will either be Allow or Deny, based on the Default Decision you’ve selected for the Okta Integration - if that’s the case, you’re ready to start assigning policies.

Assigning Policies

  1. Once the Okta integration is created, you can start assigning versions of Policies - to get started, select Policies from the tabs in your newly created integration

    SGNL - Policies

  2. Select ‘Assign Policies’

  3. Select:

    • The Policies you want to apply to the integration with the check box
    • The version of the Policy you want applied

    SGNL - Select Policies

  4. Click Next once you have the Policies and Versions configured as is appropriate

  5. Select the Enforcement mode for the Policies you chose in the previous step

    • Simulated: Policy Versions that are being simulated will only log their access decision in the SGNL logs and will not impact the access decision that SGNL hands back to an integration. Simulated policies are useful for performing what-if analysis of new policy versions as well as debugging policy changes.

      Note: It’s considered best practice to start with policies in Simulated mode, to verify that policies have been created an applied as expected

    • Enforced: Policy Versions that are being enforced will impact the access decisions that SGNL hands back to an integration. Enforced Policies will determine access for an integration

    SGNL - Set Enforcement

  6. Select your desired Enforcement mode and select Assign

  7. Versions of Policies will now be Assigned to your integration

    SGNL - Policy Assignments