I'm knew to SAML and i'm trying to understand how a clients details are stored for SSO.
If select a link in a browser to a service provider and I haven't been set up on the IDp after I have my account created at the IDp and authenticated to the SP what is stored? is it my ipddress? if I tried to connect to the same SP from a different machine would I need to be registered on the IDp again.
Or is it done another way?
Thank You
An IdP creates a SAML assertion about an authenticated subject.
Based upon the NameID format being used an opaque handle could be transmitted ("transient NameID format") or an email address ("email NameID format") or even some other id can be transmitted from the IdP to the SP. Furhtermore attribute statements could be used to transmit additional information about the subject.
Authentication happens on the IdP, however it's not defined in the SAMLv2 spec how this has to take place.
If authentication happened a "session" is established at the IdP. Most IdP implemenatations use a cookie to track the "session". So when you return to the IdP again there is no need for re-authentication unless an SP mandates this. ("ForceAuth" in the SAML AuthnRequest).
This is only a quick overview, reading the SAMLv2 tech overview (https://wiki.oasis-open.org/security/Saml2TechOverview) certainly gives you more insights.
Related
I have two service providers set up with one IdP and users are required to be authenticated twice to access both services at the same time. From my point of view, this is not "SSO" and I am thinking that there might have been settings done incorrectly and I would like to see if the community here can provide me with directions and/or possible solutions.
Just a thought - the behaviour for the authentication on each service looks valid as I understand that IdP is required to send signed SAML assertions to the providers in order to access the services. However, because I only have one IdP, can I not be authenticated just once and be able to access all the services?
Any suggestion is appreciated. Thanks.
Typically in this scenario the user would authenticate once to the IdP when the first SP SSO's to it. There would be no authentication at the IdP when the second SP SSO's to it as there's already an authentication session at the IdP for the user.
However, there might be use cases where you want the user to be authenticated at the IdP even if they already have an authentication session. The SP can set the ForceAuthn flag in the SAML authn request sent to the IdP. This requests that the IdP authenticates the user regardless of whether or not they already have an authentication session.
ADFS also has a configuration option for relying parties (SPs) to always require authentication. Take a look at the AlwaysRequireAuthentication flag.
https://learn.microsoft.com/en-us/powershell/module/adfs/set-adfsrelyingpartytrust?view=windowsserver2022-ps
we currently run our IdP on Firebase auth. One of our partner (service provider) only supports SAML 2.0. They want us to send in a request with a payload to a URL with User's email address.
I do not have much experience SAML 2.0, what you guys think the best approach for this would be?
Sorry for a vague question.
Thanks,
Sam
Firstly, You will have to configure your SP and IDP by exchanging the metadata(via a URL or XML file or manually). From the question, it seems that you are looking for IDP initiated SSO. After a user successfully authenticates with the IDP, the IDP sends a response(XML payload) which contains the user identifier typically a username or email. The SP will read the payload and after verifying the data it will create the user session in your SP.
The SAML response looks something like this.
So I'm struggling a bit with the basics of the flow of SAML. Here's the scenario I find confusing.
I have a java web application. The user is logged in. I know they want to order cookies from a 3rd party because they've clicked on the "I want chocolate chip cookies" link. I also know that "Mrs. Pillsbury Cookies Co." is a "Service Provider" because she sent me her meta-data and I've registered her with my Gluu Server (IdP). I've also sent her my IdP meta-data so we've done the whole hand-shaking thing.
My question is...how do I now send the SAMLResponse to Mrs. Pillsbury? She's given me a SOAP endpoint that is waiting for a SAMLResponse. How do I tell my Java application to get some XML from my gluu server as a SAMLReponse that I can then pass to the Pillsbury SOAP endpoint? That's the part where I'm stuck...I don't know how to get a response to forward. I can see in the metadata that there are lots of SSO endpoints
<SingleSignOnService Binding="urn:mace:shibboleth:2.0:profiles:AuthnRequest" Location="https://idp.myjavaapp.com/idp/profile/SAML2/Unsolicited/SSO"/>
<SingleSignOnService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://idp.myjavaapp.com/idp/profile/SAML2/POST/SSO"/>
<SingleSignOnService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST-SimpleSign" Location="https://idp.myjavaapp.com/idp/profile/SAML2/POST-SimpleSign/SSO
Am I supposed to hit one of those SSO endpoints and it'll generate a response that I can then forward on to Pillsbury? Can one of you SAML experts out there get me straigtened out? Thanks in advance.
There are a few ways SAML Requests/Responses can be generated.
IdP initiated:
This is a SAML Response generated w/o a SAML request. This requires the user to login/be logged into the idP and the idP will generate a SAML Response based off the SP setup in the idp.
SP initiated:
This is usually an HTTP Redirect but can be a POST as well. This is a SAML Request Redirect/POST that gets sent to the idP based of some link or button on the SP's website.
As I understand it you have the following relationship:
Your App
\
3rd Party ordering
/
IdP Server
Your app needs to make a request to the 3rd party, but also need it to authenticate against the IdP. Yes?
Normally the process works such that the 3rd party requests the token itself. Your app shouldn't have the token intended for the 3rd party -- it should only have the token for its own app.
Usually you send whatever your app-specific request is to the 3rd party first. When they receive that bit of information they hold onto it and then make a SP-Initiated authentication request to your IdP. They will attach a bit of information as part of the auth request called relay state. This bit of information is used to reconstitute the session after the IdP responds.
Once the IdP receives the request it does whatever it needs to do to authenticate the user, and sends the token back to the 3rd party. As part of that response they also send the relay state. The 3rd party then verifies the token and sets the session as necessary, then reads the relay state and sets whatever internal state is necessary to continue the order.
You're on the right track. As the previous answers have explained, it can be done one of two ways: the SP site (Pillsbury) sends you an authentication request, or you can direct your IDP/Gluu server to send an SAML message to the SP without them prompting: "unsolicited".
In the case of the first "SP-Initiated", you just create a link to the SP site for the user's browser to follow. The user's browser hits the SP site, the SP site realizes that it needs to authenticate the user: so it creates a SAML Authentication Request to your IDP endpoint, directing the user's browser there. Then your IDP server will respond according to the metadata/relationship that you've set up with the SP site. Just as one of the other answers explained, this Authentication Request can include a RelayState parameter which will be sent back to the SP to tell them where to send the user after the SAML message had been consumed & validated. I haven't used Gluu but I believe the SP would use the second endpoint you showed in your question to do this.
In the case of the second "IDP-initiated", you need to direct the user's browser to one of the Gluu server endpoints to generate a SAML assertion, which will be POST'd back to the SP site without the SP site's prompting. This one is less used because every time the user is directed to the SP site from your site, they will be forced through the AuthN process among other reasons. I believe this is the first listed endpoint that you showed in your question.
Here's a really good explanation of IDP-initiated from Shibboleth, that should help clear this up for you: https://wiki.shibboleth.net/confluence/display/SHIB2/IdPUnsolicitedSSO
Best of luck!
My understanding of the SAML (v2) protocol is that Service Providers should be interacting directly with Identity Providers to exchange authorisation request and assertion messages.
I can think of a number of reasons why this would be a bad idea (undermines message signing, gives intermediate IdP access to info from other IdP), but are there any scenarios supported by SAML that would allows the following arrangement?
SP <------> MainIdP <------> ThirdPartyIdP
So (hypothetically) assuming that MainIdP has some clever way of determining that the SP user needs to authenticate against ThirdPartyIdP, it would delegate to the ThirdPartyIdP and then receive the response, process it and reply to the SP. Does SAML allow this? (I am asking because a software supplier has suggested this approach and I believe it isn't supported, as well as being fundamentally insecure.)
The "correct" approach as I understand it is for the SP to be configured to know about both IdPs independently, and either present the user with a list to pick from, or delegate to a Discovery Service which can ask the user, or infer by some other means, which IdP to use. Is this right?
Thanks.
Most federation identity providers for SAML have the concept of a "Home Realm Discovery" screen.
The SP is "bound" to the MainIdP but the MainIdP presents a screen which shows all the other IDP's that it is federated with. From that list, you pick the ThirdPartyIdP.
Scenario:
Browser(User) requests resource from Service Provider (SP).
SP Redirects (with SAML Request) to Identity Provider (IdP).
Since it is first login, User gives the (IdP) his/her valid credentials.
IdP then redirects Browser (with SAML Response which includes SAML token) to the SP page.
I have two questions:
A. In Step 4, does the Browser store or cache the SAML Response and/or SAML token?
B. If yes, what kind of things (attributes? timeouts? protocols?) prevent me from taking that stored SAML token. Then coping it over to another computer (with a new session) and using that token to Login to the same SP?
The answer is "sort of" re caching. In your scenario, the Response will be sent via POST to the Service Provider from the browser. So the browser can "cache" the POST data that contains the SAML Response. So, just like any other POST event in browsers, if the user were to use the back button enough times after logging into the SP to get back to the POST event, the POST data could be resent to the SP.
There are a few things that help keep the Response from being hijacked -
Use of HTTPS between all parties
SP enforcement of NotBefore & NotOnOrAfter attributes
SP enforcement of one time use criteria (the SP must ensure that Response is not re-used during its validity period. If the message is received outside the validity window, then the SP should discard the message)
The IDP usually stores a session cookie on the client browser identifying the SAML session. The theft of this session cookie is probably no more protected then any other session cookie.
Using HTTPS in communication between SP and IDP will provide a great deal of protection from session hijacking.
For question A, it probably depends on the browser that you use.
For question B, there are several mechanisms that prevent the SAML response from being reused:
SubjectConfirmationData has attribute NotBefore and NotOnOrAfter that specify the time frame that the SAML assertion is valid. Thus, the SAML assertion cannot be used outside of this time frame.
SubjectConfirmationData has attribute InResponseTo that specifies the SAML request for which the SAML assertion is issued. Thus, the SAML assertion cannot be used for other SAML request.
SP must ensure that the SAML assertion is not replayed by maintaining a set of used SAML assertion.
You can read Section 4.1.4.3 and 4.1.4.5 of SAML Profiles specification.
I know this old, but the answer is yes the browser stores the SAML Token as a Cookie. (Typically) You can see it in your Browser's Cookie list, through various traffic/session inspectors like Fiddler, SAML Tracer on FF etc.