[cap-talk] forging SAML security assertions in Zebra Copy

[John Carlson]

On Feb 23, 2009, at 10:26 AM, Karp, Alan H wrote:

> John Carlson wrote:
>>
>> Are SAML security assertions unforgeable in the Zebra Copy example?
>> Say I wanted to use a type of database query language in the
>> authorization assertion.
>>
> Yes.  Each assertion is signed by the delegator, and the SOAP  
> message is signed by the user of the assertion.  These signatures  
> are checked before accepting an authorization.  I don't understand  
> what you mean by using a query language in the assertion.

Say I wanted to create an unforgeable/unmodifiable query language  
expression.  It doesn't need to be in the assertion--however, it would  
be convenient for debugging purposes to put it in the assertion.  The  
unforgeable/unmodifiable is the primary requirement.   I realize I  
could put query language expression in a directory stored under a  
swiss number on a server somewhere, but if I did that, then the client  
might not be able to tell what query language expression is being  
invoked.  On the other hand, I believe if the query language  
expression was exposed to the end user,  a type of confused deputy  
could occur--that is, the query language expression might be different  
than the capability.  If I could guarantee that the query language  
expression were the same as the capability, that would be ideal.

John