Cross-domain single sign-on

For organizations relying on AM’s session and policy services with SSO, consider cross-Domain Single Sign-On (CDSSO) as an alternative to SSO through OpenID Connect.

This example sets up PingOne Advanced Identity Cloud as an SSO authentication server for requests processed by PingGateway. For more information about about PingGateway and CDSSO, refer to Authenticate with CDSSO.

Before you start, prepare PingOne Advanced Identity Cloud, PingGateway, and the sample application as described in Example installation for this guide.

Set up PingOne Advanced Identity Cloud:

Log in to the PingOne Advanced Identity Cloud admin UI as an administrator.
Make sure you are managing the alpha realm. If not, click the current realm at the top of the screen, and switch realm.
Go to Identities > Manage > Alpha realm - Users, and add a user with the following values:
- Username: demo
- First name: demo
- Last name: user
- Email Address: demo@example.com
- Password: Ch4ng3!t
Register a PingGateway agent with the following values, as described in Register a PingGateway agent in PingOne Advanced Identity Cloud:
- ID: ig_agent
- Password: password
- Redirect URLs: https://ig.ext.com:8443/home/cdsso/redirect

(Optional) Authenticate a PingGateway agent to PingOne Advanced Identity Cloud.

PingGateway agents are automatically authenticated to PingOne Advanced Identity Cloud by a deprecated authentication module in PingOne Advanced Identity Cloud. This step is currently optional, but will be required when authentication chains and modules are removed in a future release of PingOne Advanced Identity Cloud.

Add a Validation Service:
1. In PingOne Advanced Identity Cloud, select Native Consoles > Access Management. The AM admin UI is displayed.
2. Select Services, and add a validation service with the following Valid goto URL Resources:
  - https://ig.ext.com:8443/*
  - https://ig.ext.com:8443/*?*

Set up PingGateway:

Set up PingGateway for HTTPS, as described in Configure PingGateway for TLS (server-side).
Add the following session configuration to admin.json, to ensure that the browser passes the session cookie in the form-POST to the redirect endpoint (step 6 of Information flow during CDSSO):
```
{
  "connectors": […],
  "session": {
    "cookie": {
      "sameSite": "none",
      "secure": true
    }
  },
  "heap": […]
}
```
This step is required for the following reasons:
- When sameSite is strict or lax, the browser does not send the session cookie, which contains the nonce used in validation. If PingGateway doesn’t find the nonce, it assumes that the authentication failed.
- When secure is false, the browser is likely to reject the session cookie.
  
  For more information, refer to admin.json.
Set an environment variable for the PingGateway agent password, and then restart PingGateway:
```
$ export AGENT_SECRET_ID='cGFzc3dvcmQ='
```
The password is retrieved by a SystemAndEnvSecretStore, and must be base64-encoded.

Add the following route to PingGateway to serve the sample application .css and other static resources:

Linux
Windows

$HOME/.openig/config/routes/00-static-resources.json

appdata\OpenIG\config\routes\00-static-resources.json

{
  "name" : "00-static-resources",
  "baseURI" : "http://app.example.com:8081",
  "condition": "${find(request.uri.path,'^/css') or matchesWithRegex(request.uri.path, '^/.*\\\\.ico$') or matchesWithRegex(request.uri.path, '^/.*\\\\.gif$')}",
  "handler": "ReverseProxyHandler"
}

Add the following route to PingGateway, and correct the value for the property amInstanceUrl:

Linux
Windows

$HOME/.openig/config/routes/cdsso-idc.json

appdata\OpenIG\config\routes\cdsso-idc.json

{
  "name": "cdsso-idc",
  "baseURI": "http://app.example.com:8081",
  "condition": "${find(request.uri.path, '^/home/cdsso')}",
  "properties": {
    "amInstanceUrl": "https://myTenant.forgeblocks.com/am"
  },
  "heap": [
    {
      "name": "SystemAndEnvSecretStore-1",
      "type": "SystemAndEnvSecretStore"
    },
    {
      "name": "AmService-1",
      "type": "AmService",
      "config": {
        "url": "&{amInstanceUrl}",
        "realm": "/alpha",
        "agent": {
          "username": "ig_agent",
          "passwordSecretId": "agent.secret.id"
        },
        "secretsProvider": "SystemAndEnvSecretStore-1",
        "sessionCache": {
          "enabled": false
        }
      }
    }
  ],
  "handler": {
    "type": "Chain",
    "config": {
      "filters": [
        {
          "name": "CrossDomainSingleSignOnFilter-1",
          "type": "CrossDomainSingleSignOnFilter",
          "config": {
            "redirectEndpoint": "/home/cdsso/redirect",
            "authCookie": {
              "path": "/home",
              "name": "ig-token-cookie"
            },
            "amService": "AmService-1"
          }
        }
      ],
      "handler": "ReverseProxyHandler"
    }
  }
}

Notice the following features of the route compared to cdsso.json in CDSSO for PingGateway in standalone mode, where PingAM is running locally:

The AmService URL points to PingAM in PingOne Advanced Identity Cloud.
The AmService realm points to the realm where you configure your PingGateway agent.

Restart PingGateway.

Test the setup:
1. In your browser’s privacy or incognito mode, go to https://ig.ext.com:8443/home/cdsso.
  
  The PingOne Advanced Identity Cloud login page is displayed.
2. Log in to PingOne Advanced Identity Cloud as user demo, password Ch4ng3!t.
  
  PingAM calls /home/cdsso/redirect, and includes the CDSSO token. The CrossDomainSingleSignOnFilter passes the request to sample app.

PingGateway 2024.6

Cross-domain single sign-on