This document will be used to outline the process for implementing Azure’s ACS namespace as a trusted identity provider to an on-premise SharePoint environment, utilizing external identity providers such as Facebook, Yahoo, or Windows Live ID to pass manipulated claims as a standardized trusted token to SharePoint
Preface, Considerations, Prerequisites
- Azure ACS authentication with SharePoint is a free service as of 12/2014. The service requires a subscription to Azure, but costs no money. A $0 spending limit can be set to prevent the possibility of any charges coming through from this account.
- The Azure ACS system can utilize any Identity Provider that can export an OpenID claim
- SharePoint 2013 does not support SAML 2.0, SAML 1.1 must be used
- As of 12/2014, Windows Live ID can only export a nameidentifier claim, but this can be mapped to an email address claim to use as a UPN for login
- An x.509 SSL certificate needs to be uploaded to Azure to sign tokens, and to explicitly trust in SharePoint
Azure ACS – ACS (access control system) is a free feature of Azure that allows the developer to create a namespace that can tie external Identity Providers incoming tokens to a single claim to a web application
Azure Namespace – the item in Azure that provides the URL for all Identity Providers, Relying Party Applications, Rule Group Settings, and Certificates and Keys to be trusted
Identity Provider – an external service, such as Yahoo!, Facebook, or Windows Live ID, that provides the inherently trusted authentication to SharePoint
Relying Party Application – these are the web applications that are connected to the namespace that receive the token that is output from the Azure ACS namespace. In this walkthrough, SharePoint 2013 is our Relying Party Application
Rule Groups – Rule groups are the list of incoming claims tied to claim issuers/identity providers, how they may be mapped when exported, as well as any customizations that need to happen for the token itself
Creating the Namespace
- Login to the Azure management portal at https://manage.windowsazure.com with the Azure account created prior to this work. Note: Ensure that this account has a subscription set up prior to continuing any further, any work created with a trial account will expire once the trial is over, and are unable to be transferred to a setup account
- Once logged into the management console, click the large NEW button at the bottom left of the screen to begin the process of creating a namespace
- Navigate App Services > Active Directory > Access Control > Quick Create:
- Give the namespace a name that makes sense for the authentication set up (this won’t be an actively used URL by an end-user). Select your region, and the subscription that has been set up (Pay-As-You-Go, or another valid subscription, NOT free trial). The namespace status will change from creating to active:
- Click on the newly created namespace, and click the manage button on the bottom ribbon, this will take you to the Silverlight based Windows Azure Platform Access Control Service control panel:
- Utilize the Getting Started steps that appear on the homepage of this control panel for much of the work. You will now want to set up the Identity Providers:
Making Windows Live ID Work for SharePoint 2013 Authentication
Since the Windows Live ID Identity Provider is a preset default in the Azure ACS namespace, I will use it as a full example on configuring the claim issuer for authentication in SharePoint, and will later lead into how to configure additional Identity Providers.
Configure Relying Party Applications
- Navigate to the Relying party applications management by clicking the URL on the left-hand side of the ACS administrative panel
- Click the Add URL at the top left of the Relying Party Applications table
- On the configuration page, enter in the following information:
Name: a display name such as “SharePoint2013” is fine for this as it is simply a display name for SharePoint’s trust with ACS
Realm: the realm will be equal the resolvable url for your SharePoint web application (https://winchestertonfieldville.ia.gov/) would work fine if this is your SharePoint web application URL
Return URL: this is the URL in which ACS will return tokens to SharePoint. This will always be the same URL as the realm defined above, with “/_trust” appended to the end (https://winchestertonfieldville.ia.gov/_trust)
Error URL (optional): This is the URL for an optional error page in case authentication fails
Token Format: Choose SAML 1.1, SharePoint 2013 is NOT compatible with SAML 2.0
Token lifetime (secs): This value represents the seconds that the token is valid before expiring, or how long the user will be able to hit the realm URL repeat times and be auto-authenticated back in to the environment. The default value of 600 seconds is typically on the low side. Set this value to 3600 seconds (equal to the default value in ADFS).
Identity Providers: the list of Identity Providers that you would like to have as optional authentication methods when users hit the realm’s login page. Each Identity Provider will show in the login drop down
Rule Groups: leave the check box to create a new rule group as we will be doing this in the next step
Token Signing: Choose whether to Use service namespace certificate or Use a dedicated certificate. For the purposes of this walk through, I would recommend choosing Use a dedicated server and upload the X.509 certificate .pxf file to use for when signing. Browse to the file, upload, and input the password that was created when it was exported from the server.
- Click Save
Configure Rule Groups
The rule groups are the configuration for what claims Azure will receive from the Identity Providers, as well as how they will map these claims to the output token.
- Navigate to the Rule Groups page by clicking the URL on the left-hand navigation
- Click the “Default Rule Group for <RelyingPartyApplication>” that was automatically created when we set up the Relying Party Application
- On the Edit Rule Group page, feel free to edit the name for the rule group
- In the Rules table, click the Generate URL. You will notice that the Rules table currently shows “No rules have been added. Click Generate to generate rules automatically, or click Add to add rules manually.” Note – If additional Identity Providers are added at a later time, use this option to generate new rules for the new identity providers
- On the following page, click the checkbox next to Windows Live ID, and click Generate
- You will then see the that the nameidentifier output claim from Windows Live ID is listed as a rule. Click on the nameidentifier URL.
- On the resulting page, you can see how to configure the input/ouput of this claim for how ACS will prep it for the output token that will be trusted by SharePoint. By default, nameidentifier is not a usable claim for a login in SharePoint. To address this, we will map the output claim type to email address.
- For everything under the If section, leave default
- For the “Then” section, change the select type dropdown from http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier to http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress to map the claim from the nameidentifier URI to a usable email address login
- You can leave all other items as default, or add information under “Rule Information” that will explain that we are mapping the Windows Live ID nameidentifier claim to an emailaddress output claim
Upload Token Signing Certificate
Azure ACS uses an X.509 certificate to digitally sign the tokens it generates. You can also increase the functionality of this certificate to include encryption/decryption of the tokens themselves. Many users will use the makecert utility to create a self-signed certificate for testing purposes, but do not do this in a production environment.
- Click the Certificates and Keys URL on the lefthand side of the Azure ACS configuration page
- Click the Add URL at the top of the Token Signing table
- On the “Add Token-Signing Certificate or Key” page, select the correct Relying Party Application in the dropdown.
- Select X.509 Certificate for type
- Click Choose file and upload the .pfx file. Note: On this page, it also shows how to use the MakeCert utility from the Microsoft SDK to make this certificate.
- Click Save
SharePoint 2013 Configuration
Within SharePoint, we will move forward in this walkthrough with the assumption that the Web Application within SharePoint 2013 has already been created with a friendly URL assigned to it.
- Log in to the Central Admin server
- Open a PowerShell ISE session as an administrator and run the following:
- I would recommend running the above code line by line to ensure you can identify any errors as they happen, rather than an error that you can’t attribute to a single line of code when bulk running the block
- Open Central Administration and click Manage Web Applications
- Click the web application that we have been using thus far, and click Authentication Providers in the ribbon.
- In the appropriate zone, you should be able to see empty check boxes for the newly created Trusted Identity Providers that we have set up. Check the boxes next to Windows Live ID
- Press Save
- SharePoint now knows to trust any SAML1.1 tokens that come from the specific Azure ACS namespace that we have created, and knows how to parse the claims within the token.
#Add snapin to allow SharePoint PowerShell comamnds
#set the realm to equal the URL for the SharePoint web application. This must match the realm value used when creating the relying party application within Azure ACS
$realm = "https://westchestertonfieldville.ia.gov/"
#replace <namespace> with the name of the ACS namespace created previously, select http or https depending on your SharePoint WebApp URL, replace <realm> with the URL for the SharePoint web application. This establishes a trust between SharePoint and the Azure ACS token signing certificate. This can be viewed further within Central Administration under Security > Manage Trusts. Ensure that this signin page resolves
$signinurl = "https://<NAMESPACE>.accesscontrol.windows.net:443/v2/wsfederation?wa=wsignin1.0&wtrealm=<HTTPorHTTPS>%3a%2f%2f<REALM>/%2f"
# Set variables for the location of the certificate and create the trusted root authority. This should be the same X.509 cert used as with the token signing cert used when creating the Relying Party application within Azure
$certloc = "C:\westchestertonfieldvillecert.cer"
$rootcert = Get-PfxCertificate $certloc
New-SPTrustedRootAuthority "Windows Azure ACS" -Certificate $rootcert
$cert = New-Object System.Security.Cryptography.X509Certificates.X509Certificate2($certloc)
#map the claim rules to pass the claims returned from Azure ACS to the SharePoint STS
# Email Field
$map1 = New-SPClaimTypeMapping -IncomingClaimType "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier" -IncomingClaimTypeDisplayName "Name Identifier" –LocalClaimType "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/upn"
$map2 = New-SPClaimTypeMapping -IncomingClaimType "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress" -IncomingClaimTypeDisplayName "Email" -SameAsIncoming
$map3 = New-SPClaimTypeMapping -IncomingClaimType "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name" -IncomingClaimTypeDisplayName "Name" -SameAsIncoming
#Create New Trusted Identity Provider in SharePoint 2013 to recognize the passed on claims within the trusted token
New-SPTrustedIdentityTokenIssuer -Name "ACS" -Description "ACS Id Token Issuer" -Realm $realm -ImportTrustCertificate $cert -ClaimsMappings $map1,$map2,$map3 -SignInUrl $signinurl -IdentifierClaim $map1.InputClaimType
You are now complete! You now should be able to hit the SharePoint Web Application URL, be redirected to an Azure ACS hosted login page, be able to choose between windows authentication or Windows Live ID, be redirected to the Windows Live ID login page to authenticate, and automatically be pushed back to SharePoint. As of our current configuration performed thus far, the users will hit a “You are not authorized to view this page” SharePoint page. For security, I would recommend enabling Access Request settings for the root Site Collection, and setting the recipient to a HA individual, or a distribution group to be able to triage requests from possible users as they hit your environment.