SAML provides a standard XML format to express and exchange security
assertions. Assertions come in three flavors: authentication, authorization,
and attributes. You get these assertions from some type of trust authority,
such as a single sign-on service or an entitlement service. SAML defines the
protocols (SOAP messages) that you use to get these assertions.

One of the primary reasons why you might want to use SAML is to support
single sign-on. But if you don't have a SAML authentication authority, then
you probably don't want to use SAML.

In WS-Security speak, a SAML assertion is an XML security token. Once you
have a SAML token, you can relay that security information in your SOAP
messages (in a SOAP header) using WS-Security. WS-Security also supports a
number of other security tokens, such as X.509 certificates, Kerberos
tickets, XrML tokens, XCBF tokens, or a simple userID/password token.

But you don't need to use either SAML or WS-Security to implement
authentication or authorization. There are a number of authentication
mechanisms that you can use: HTTP Basic, HTTP Digest, SPKM (X.509
certificates). The challenge that you need to solve is mapping these
transport-level authentication mechanisms to a security principal within
your environment. You will need to implement a transport-level interceptor
to capture the authentication information and map it to a principal. Then
you need to carry that context with your request until you get to the
service dispatch point, at which point you can use JAAS to determine if that
principal is authorized to access the requested service.

If you're using WS-Security, then you must write a header processor that
takes the security token and maps it to a principal, and then use JAAS to
check authorization.

Anne

> -----Original Message-----
> From: Nisha Menon [mailto:[EMAIL PROTECTED]
> Sent: Monday, March 17, 2003 5:25 AM
> To: [EMAIL PROTECTED]
> Subject: RE: Authorization using WS security and SAML
>
>
>
> Yip... I get it now... :-)
>
> Ok so here's the deal...
>
> The SOAP message that comes in is parsed and the authentication
> information is extracted. (I guess that module would need to look out
> for a pattern followed since we'd have to know which standard is being
> used to pass the authentication information. i.e username/password or
> certificates or security tokens etc) Depending on that, we'd have to
> re-route the process to an appropriate authentication module. Each
> module extracts the required information in it's own way and
> authenticates the message.
>
> The next step is authorization. Now this is what I'd be more interested
> in.
> Once I have the authentication, I need to authorize the SOAP request.
> Here too SAML can be used to set assertions. And then again maybe not.
> So I'd have to have separate modules for authorization as well. Each of
> which relate to internal mappers (what are mappers?? Look up DBs??)
>
> This is the basic requirement. The hassle is, I'm new to webservices and
> I was wondering what standards, protocols and APIs I need to work with
> and where they'd fit in.
>
> As far as I see it, (that may not be seeing much)
> WS-Security and SAML could be one of the ways to secure a message and
> that would comprise of one of the many authorization modules I was
> talking about earlier. So I'd need to extract that information from the
> SOAP message and work on it. In order to do that I'd use JAAS APIs? (u
> think?) within which I use OpenSAML to work on the extraction? (just
> guessing here..) After extraction I need to map the actors. And that
> should complete the authorization process.
>
> How does that sound?
>
> Dims:
> You had suggested TSIK? I gather they're java APIs for SAML etc.. Would
> that replace JAAS in the above picture?
>
> Regards,
> Nisha
>
>
> -----Original Message-----
> From: Ricky Ho [mailto:[EMAIL PROTECTED]
> Sent: Monday, March 17, 2003 11:40 AM
> To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
> Subject: RE: Authorization using WS security and SAML
>
>
> I haven't closely track the OASIS activity.  They are supposed to
> standardize how to put a SAML assertion inside a WS-Security header.
> JAAS is a Java API for doing authentication and authorization.  Compare
> API
> with protocol is like oranges and apples.
>
> Rgds, Ricky
>
> At 09:23 AM 3/17/2003 +0530, Nisha Menon wrote:
> >Ricky,
> >
> >Being new to all of this, it's been great help so far already! I've
> >been trying to evaluate the available standards to see what I need to
> >work with on this module. And from what I've been reading over the last
>
> >month or so, I'd narrowed down to SAML and WS-Security on the basis
> >that they work well together and they're very popular. It'd just been a
>
> >week since I'd heard about XACML (duh!) and I must admit it had me all
> >confused! :-) thx for helpin me out there! Ok so you've told me about
> >what SAML does (and I guess I can use OpenSAML APIs for development
> >there) but what about WS-Security? Does embedding SAML assertions into
> >the SOAP Security Header within the <wsse:Security> tag complete the
> >picture? Also, how does JAAS compare to all of these standards in
> >authorization? Where would it fit in?
> >
> >Lotsa questions there! :-(
> >
> >Regards,
> >Nisha
> >
> >
> >-----Original Message-----
> >From: Ricky Ho [mailto:[EMAIL PROTECTED]
> >Sent: Sunday, March 16, 2003 10:08 PM
> >To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
> >Subject: Re: Authorization using WS security and SAML
> >
> >
> >SAML is about specifying the XML format of your authorization decision
> >outcome (authorization assertion).  It also defines a protocol how to
> >request the assertion.  SAML doesn't describe how the decision should
> >be
> >
> >made.  XACML is attempting to standardize how such decision rules
> >should be specified.  So it is completely solving an orthogonal
> >problem.
> >
> >I'm not sure how important to standardize decision making rules because
> >there is NO "inter-operability" requirement for that.  There is NO need
>
> >to communicating how I made my decision to my business partners.  The
> >value of
> >XACML is "portability" of my decision criteria across multiple vendor
> >products.  However, "portability" has never been a goal for any XML
> >standard.  It is arguable how important XACML will be.
> >
> >Best regards,
> >ricky
> >
> >At 06:38 PM 3/16/2003 +0530, Nisha Menon wrote:
> > >hi,
> > >
> > >i am trying to create an authorization module for web services that
> > >is independant of the application and to authorize i've chosen to use
>
> > >WS-Security and SAML. would anyone on this list be familiar with
> > >similar implementation? or
> >have
> > >any references for the same?
> > >also, how does XACML compare to SAML?
> > >
> > >thank you,
> > >
> > >nisha
> > >
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