APM Cookbook: SAML IdP Chaining
As an APM subject mater expert at F5 I often find myself in situations where a customer or colleague needs an example of a particular configuration. While most of these requests are easily handled with a call or WebEx I'm a firm believer in sharing knowledge through documentation.. and I don't like getting calls at 3 AM. If you're like me you grew up with the O'Reilly Cookbook series which served as a great reference document for various development or server configuration tasks. My goal is to create a similar reference resource here on DevCentral for those one-off scenarios where a visual example may help your complete your task. For the first APM Cookbook series I'll discuss SAML IdP chaining. Overview Security Assertion Markup Language, more commonly known as SAML, is a popular federated authentication method that provides web based single sign-on. One of the key security advantages to SAML is the reduction in username/password combinations that a user has remember... or in my experience as a security engineer the number of passwords written on a post-it note stuck to their monitor. There are two major services in a SAML environment: IdP - Identity Provider SP - Service Provider The identity provider is the SAML service that authenticates the user and passes an assertion to then service providers proving the user's identity. F5's APM performs both IdP and SP services and allows customers to easily deploy federated authentication in their environment. In more complex scenarios you may run across a requirement where multiple SAML IdPs need to be chained together. This comes up from time to time when customers have contractors that utilize federated authentication for authorization to corporate resources. Example For our configuration we have the Globex Corporation that uses APM to authenticate uses to Office 365. Globex hire contractors from Acme Corp. who authenticate using the Acme Corp. ADFS environment. However, since Office 365 is configured to authenticate against the Globex APM we need to convert the Acme Corp. SAML assertion into a Globex SAML assertion, which is known as IdP chaining. The step ladder for this process is shown below: 1. User requests https://outlook.com/globex.com 2 - 3. Office 365 redirects user to idp.globex.com 3 - 4. idp.globex.com determines user is a contractor and redirect user to sts.acme.com 5 - 8. User authenticates using Acme credentials and is then redirect back to idp.globex.com 9. idp.globex.com consumes the Acme SAML assertion and creates a Globex SAML assertion 10. User is redirected back to Office 365 11 - 12. Office 365 consumes the Globex SAML assertion and displays the user's mail Configuration To configure your APM SAML IdP to accept incoming assertion from sts.acme.com we need to create an external SP connector. Under the Access Policy -> SAML -> BIG-IP as SP configuration section: 1. Create a new SAML SP Service 2. Export the SP metadata and configure sts.acme.com accordingly (follow your IdP vendor's documentation) 3. Click the External IdP Connectors menu at the top 4. Click the dropdown arrow on the create button and choose From Metadata (import the metadata from sts.acme.com) 5. Bind the Local SP service to the external IdP connector Now that idp.globex.com and sts.acme.com are configured to trust one another we need to configure the APM IdP to consume the sts.acme.com SAML assertion. The IdP's Visual Policy Editor should look similar to the image below: 1. The Decision Box asks the user what company they're with. This is a simple example but more elaborate home realm discovery techniques can be used. 2. The SAML Auth box is configured to consume the sts.acme.com assertion 3. Since we no longer have a login form on the IdP we need to set a few APM session variables: session.logon.last.username = Session Variable session.saml.last.identity session.logon.last.logonname = Session Variable session.saml.last.identity 4. Create an Advanced Resource Assign that matches your existing IdP Advance Resource Assign. Conclusion This particular post was a little longwinded due to the steps required but overall is a fairly simple configuration. So the next time someone asks if your F5 can do IdP chaining you can confidently reply "Yes and I know how to do that".
APM Cookbook: Single Sign On (SSO) using Kerberos
To get the APM Cookbook series moving along, I’ve decided to help out by documenting the common APM solutions I help customers and partners with on a regular basis. Kerberos SSO is nothing new, but seems to stump people who have never used Kerberos before. Getting Kerberos SSO to work with APM is straight forward once you have the Active Directory components configured. Overview I have a pre-configured web service (IIS 7.5/Sharepoint 2010) that is configured for Windows Authentication, which will send a “Negotiate” in the header of the “401 Request for Authorization”. Make sure the web service is configured to send the correct header before starting the APM configuration by accessing the website directly and viewing the headers using browser tools. In my example, I used the Sharepoint 2010/2013 iApp to build the LTM configuration. I’m using a single pool member, sp1.f5.demo (10.10.30.2) listening on HTTP and the Virtual Server listening on HTTPS performing SSL offload. Step 1 - Create a delegation account on your domain 1.1 Open Active Directory Users and Computers administrative tool and create a new user account. User logon name: host/apm-kcd.f5.demo User logon name (pre-Windows 2000): apm-kcd Set the password and not expire 1.2 Alter the account and set the servicePrincipcalName. Run setspn from the command line: setspn –A host/apm-kcd.f5.demo apm-kcd A delegation tab will now be available for this user. Step 2 - Configure the SPN 2.1 Open Active Directory Users and Computers administrative tool and select the user account created in the previous step. Edit the Properties for this user Select the Delegation tab Select: Trust this user for delegation to specified services only Select: Use any authentication protocol Select Add, to add services. Select Users or Computers… Enter the host name, in my example I will be adding HTTP service for sp1.f5.demo (SP1). Select Check Names and OK Select the http Service Type and OK 2.2 Make sure there are no duplicate SPNs and run setspn –x from the command line. Step 3 - Check Forward and Reverse DNS DNS is critical and a missing PTR is common error I find when troubleshooting Kerberos SSO problems. From the BIG-IP command line test forward and reverse records exist for the web service using dig: # dig sp1.f5.demo ;; QUESTION SECTION: ;sp1.f5.demo. IN A ;; ANSWER SECTION: sp1.f5.demo. 1200 IN A 10.10.30.2 # dig -x 10.10.30.2 ;; QUESTION SECTION: ;2.30.10.10.in-addr.arpa. IN PTR ;; ANSWER SECTION: 2.30.10.10.in-addr.arpa. 1200 IN PTR sp1.f5.demo. Step 4 - Create the APM Configuration In this example I will use a Logon Page to capture the user credentials that will be authenticated against Active Directory and mapped to the SSO variables for the Kerberos SSO. 4.1 Configure AAA Server for Authentication Access Policy >> AAA Servers >> Active Directory >> “Create” Supply the following: Name: f5.demo_ad_aaa Domain Name: f5.demo Domain Controller: (Optional – BIG-IP will use DNS to discover if left blank) Admin Name and Password Select “Finished" to save. 4.2 Configure Kerberos SSO Access Policy >> SSO Configurations >> Kerberos >> “Create” Supply the following: Name: f5.demo_kerberos_sso Username Source: session.sso.token.last.username User Realm Source: session.ad.last.actualdomain Kerberos Realm: F5.DEMO Account Name: apm-kcd (from Step 1) Account Password & Confirm Account Password (from Step1) Select “Finished” to save. 4.3 Create an Access Profile and Policy We can now bring it all together using the Visual Policy Editor (VPE). Access Policy >> Access Profiles >> Access Profile List >> “Create” Supply the following: Name: intranet.f5.demo_sso_ap SSO Configuration: f5.demo_kerberos_sso Languages: English (en) Use the default settings for all other settings. Select “Finished” to save. 4.4 Edit the Access Policy in the VPE Access Policy >> Access Profiles >> Access Profile List >> “Edit” (intranet.f5.demo_sso_ap) On the fallback branch after the Start object, add a Logon Page object. Leave the defaults and “Save”. On the fallback branch after the Logon Page object, add an AD Auth object. Select the Server Select “Save” when your done. On the Successful branch after the AD Auth object, add a SSO Credential Mapping object. Leave the defaults and “Save”. On the fallback branch after the SSO Credential Mapping, change Deny ending to Allow. The finished policy should look similar to this: Don't forget to “Apply Access Policy”. Step 5 – Attach the APM Policy to the Virtual Server and Test 5.1 Edit the Virtual Server Local Traffic >> Virtual Servers >> Virtual Server List >> intranet.f5.demo_vs Scroll down to the Access Policy section and select the Access Profile. Select “Update” to save. 5.2 Test Open a browser, access the Virtual Server URL (https://intranet.f5.demo in my example), authenticate and verify the client is automatically logged on (SSO) to the web service. To verify Kerberos SSO has worked correctly, check /var/log/apm on APM by turning on debug. You should see log events similar to the ones below when the BIG-IP has fetched a Kerberos Ticket. info websso.1[9041]: 014d0011:6: 33186a8c: Websso Kerberos authentication for user 'test.user' using config '/Common/f5.demo_kerberos_sso' debug websso.1[9041]: 014d0018:7: sid:33186a8c ctx:0x917e4a0 server address = ::ffff:10.10.30.2 debug websso.1[9041]: 014d0021:7: sid:33186a8c ctx:0x917e4a0 SPN = HTTP/sp1.f5.demo@F5.DEMO debug websso.1[9041]: 014d0023:7: S4U ======> ctx: 33186a8c, sid: 0x917e4a0, user: test.user@F5.DEMO, SPN: HTTP/sp1.f5.demo@F5.DEMO debug websso.1[9041]: 014d0001:7: Getting UCC:test.user@F5.DEMO@F5.DEMO, lifetime:36000 debug websso.1[9041]: 014d0001:7: fetched new TGT, total active TGTs:1 debug websso.1[9041]: 014d0001:7: TGT: client=apm-kcd@F5.DEMO server=krbtgt/F5.DEMO@F5.DEMO expiration=Tue Apr 29 08:33:42 2014 flags=40600000 debug websso.1[9041]: 014d0001:7: TGT expires:1398724422 CC count:0 debug websso.1[9041]: 014d0001:7: Initialized UCC:test.user@F5.DEMO@F5.DEMO, lifetime:36000 kcc:0x92601e8 debug websso.1[9041]: 014d0001:7: UCCmap.size = 1, UCClist.size = 1 debug websso.1[9041]: 014d0001:7: S4U ======> - NO cached S4U2Proxy ticket for user: test.user@F5.DEMO server: HTTP/sp1.f5.demo@F5.DEMO - trying to fetch debug websso.1[9041]: 014d0001:7: S4U ======> - NO cached S4U2Self ticket for user: test.user@F5.DEMO - trying to fetch debug websso.1[9041]: 014d0001:7: S4U ======> - fetched S4U2Self ticket for user: test.user@F5.DEMO debug websso.1[9041]: 014d0001:7: S4U ======> trying to fetch S4U2Proxy ticket for user: test.user@F5.DEMO server: HTTP/sp1.f5.demo@F5.DEMO debug websso.1[9041]: 014d0001:7: S4U ======> fetched S4U2Proxy ticket for user: test.user@F5.DEMO server: HTTP/sp1.f5.demo@F5.DEMO debug websso.1[9041]: 014d0001:7: S4U ======> OK! Conclusion Like I said in the beginning, once you know how Kerberos SSO works with APM, it’s a piece of cake!
Can SSL VPN client handle multiple simultaneous sessions?
From a single Windows machine, we have a need to have the F5 SSL VPN client connect both to multiple external organizations at once, and also to connect to single organizations by multiple tunnels, with separate credentials. If there's a way to do either of these, it's not obvious to us. It seems like only one SSL VPN client instance can run per machine, and that instance can only handle a single tunnel, with a single set of credentials, to a single remote location. It's testament to F5's market penetration that we find ourselves needing to do more than that. Is there a way? Thanks, Whit
LDAPS Monitor with Certificate Expiration
Hi Team, I have been working with my AD team trying to resolve a problem where they forget to update a Domain Controller certificate and it expires and ADLDAPS queries fail since they dont bind to expired certificates. They have requested to see if we can drop a member out of the pool if the certificate is expired ( ie, not a valid SSL cert ) I have been messing with the LDAP Health monitor, turning on the Security settings, but I dont believe this would actually check that a certificate is valid or not. I know with server side SSL configuration you can enable SSL authentication but would just stop traffic from flow, not actually drop a member out of the pool. Any ideas ?Problems load balancing printing
Followed this guide to configure load balancing MS printing with npath routing: http://blog.loadbalancer.org/load-balancing-microsoft-print-server/ The problem is when I try to connect to the printer with the FQDN of virtual server (eg. \\virtualserver.mydomain.com) I get the error "Operation could not be completed (error 0x00000709). Double check the printer name and make sure that the printer is connected to the network.". If I connect to the VIP (eg. \\192.168.0.10) it works fine. If I connect to the host directly (by hostname or IP) it works fine. Any ideas?
Outlook Client Prompting for Password
A few months ago we implemented Exchange 2010 with the help of our LTMs. However it has come to light that people have been complaining about how sometimes they are being prompted to log in after they've been logged in all day. What they don't understand is that when they switch between networks "Wired to wireless" or vice versa, their IP address changes so the CAS server they land on is likely different, prompting them to re-authenticate. I don't suppose there is an F5 solution to stop these password prompt. The best solution I came up with was to run Outlook anywhere and do the persistence based on cookies. Are there any other ideas out there?Sharepoint 2010 Health Monitor
I have an HTTP GET health monitor setup for our Sharepoint 2010 servers. The health montior seems to work as I am seeing 200s come back from the server after authentication. However, what I'm also seeing is the health monitor sending along several GETs without the NTLM credentials and those come back with 401 authentication errors: Logs from Sharepoint server...top two are not successful as the LTM did not send along the credentials of PPL\spsearchqa. Bottom two are successful with the creds: 2015-04-24 13:48:04 xxx.xxx.xxx.xxx GET /sitepages/Home.aspx - 80 - xxx.xxx.xxx.xxx Mozilla/5.0+(Windows+NT+5.1;+rv:2.0.1)+Gecko/20100101+Firefox/4.0.1 401 2 5 5 2015-04-24 13:48:04 xxx.xxx.xxx.xxx GET /sitepages/Home.aspx - 80 - xxx.xxx.xxx.xxx Mozilla/5.0+(Windows+NT+5.1;+rv:2.0.1)+Gecko/20100101+Firefox/4.0.1 401 1 2148074254 5 2015-04-24 13:48:08 xxx.xxx.xxx.xxx GET /sitepages/Home.aspx - 80 PPL\spsearchqa xxx.xxx.xxx.xxx Mozilla/5.0+(Windows+NT+5.1;+rv:2.0.1)+Gecko/20100101+Firefox/4.0.1 200 0 64 12045 2015-04-24 13:48:14 xxx.xxx.xxx.xxx GET /sitepages/Home.aspx - 80 PPL\spsearchqa xxx.xxx.xxx.xxx Mozilla/5.0+(Windows+NT+5.1;+rv:2.0.1)+Gecko/20100101+Firefox/4.0.1 200 0 64 10075 Here is how my health monitor is setup: Any help would be very much appreciated. Thank you!
Office 365 with APM as IdP (no ADFS), troubleshooting
hello, I have starting a non-hybrid deployment of Office365 with DirSync (sync is working). My domain is a subdomain in a forest. I followed the F5 deployment guide (manual config, no iApp) and have the office365 portal redirection to my IdP (APM 11.6 HF5) and the IdP redirection with assertion (which seems correct) to the Office 365 portal. But signon doesn't work and I get an error 80043431. Questions: cannot find Microsoft troubleshooting guides that do consider a deployment without ADFS. I would like to verify the SSO configuration of Office365 but the PS command Get-MsolFederationProperty -DomainName seem to work only with ADFS... get an error Get-MsolFederationProperty : Failed to connect to Active Directory Federation Services 2.0 on the local machine. Please try running Set-MsolADFSContext before running this command again. Does anyone knows a way to get the SSO configuration in a deployment without ADFS? has anyone gone through the same error and found the solution? Thanks AlexAPM : Radius and AD same logon page fail
Hi, based on the following article : https://devcentral.f5.com/questions/bigip-apm-ad-rsa-auth I'm trying to implement a single logon page with these 2 Authentication mode : "Radius" and "AD" (same login for both but not the same password) : Bellow a screenshot of my current VPE applied to my VS (OWA 2010) : Variable Assign - keep AD and RSA pwd : session.logon.last.password = Session Variable session.logon.last.token (unsecure) session.logon.temp.password = Session Variable session.logon.last.password (unsecure) Variable Assign AD pwd : session.logon.last.password = Session Variable session.logon.temp.password (unsecure) Unfortunately I always have the following errors message in my APM report : * RADIUS module: authentication with 'username' failed: Access-Reject packet from host IP-of-my-radius-server * RADIUS module: parseResponse():Access-Reject packet from host IP-of-my-radius-server:port Please help me !!!
Layer 4 redirect any help appreciated
Hey everyone, looking for some assistance in creating an iRule to use for ADFS 2012 R2. Since it no longer relies on IIS you need to create an L4 VS on the F5 LTM. Any help would be greatly appreciated!! This is what I am looking to accomplish: redirect from http to https append text to uri. Example: users type in: http://site.domain.com It is redirected to: https://site.domain.com/misc/anything.any
