[Jsdsi-users] ACL and AuthCert

[Dav C. <dav...@gm...>]

I'm making progress on my JSDSI app. I can create keypairs, name
certificates and auth certificates so far. There's a GUI interface
that uses the file system for persistence (serialized unencrypted
HashMap for the KeyPairs at the moment, and a directory of
jsdsi.Certificate.toSequence() .certificate files created with
jsdsi.ObjOutputStream).

I'm a little confused with how jsdsi.Acl and jsdsi.AuthCert work together. 

Is the idea that the AclEntry is the 'base' for all authorizations? 

Is this scenario compatible with the design intentions? :

I want to grant a permission to access my webcam to the principal I
call Alice and her family.

1) I create a jsdsi.Tag that represents the webcam access. Say a
StringTag with the value "WEBCAM-READ"
2) I create a NameCert that binds Alice's public key to the local
namespace name "Alice". I then wrap this in a jsdsi.Certificate and
store it in my CertStore.
3) I create an AclEntry that associates the StringTag with Alice and
gives propagate permission.
4) I store this in an jsdsi.Acl object. 
5) The jsdsi.Acl object is persisted to disk and should be encrypted
to avoid tampering.

6) Somehow (application-responsibility) communicate to the holder of
the Alice keypair that she has access to something represented as a
StringTag named "WEBCAM-READ" at some host.

here's where I start getting really confused....

7) Alice creates an AuthCert that delegates access to the StringTag
"WEBCAM-READ" to people bound to her local namespace as Family. This
is the only place where an AuthCert comes into play, when delegating a
Tag that was defined in someone else's Acl?

8) Alice wants to access the resource, so she creates some sort of
request JSDSI object that specifies
- the StringTag she is requesting access to
- A signature generated with her private key
....what does this request look like?

9) When I receive this request, I have to verify that it comes from
Alice (using the Signature) and that Alice has access (using the Acl).
I assume that there are jsdsi facilities for doing this (probably
CertPathValidator or Prover I guess), but I haven't got this far yet
so I don't really know.

10) I'm even more confused as to how her family members create their
requests, although I assume if I can figure out how to complete a
circuit for Alice then I'll start to see how her family can do it.

Am I on track at all here? I know this is probably a case of RTFM, but
there's so many different manuals, and frankly I don't trust that all
of them are consistent with the current JSDSI since some are for SPKI,
some are for SDSI (before the merge), some are for the old Java
implementation, some are for implementations in other languages....
Whenever I get this working I'd like to write up some sort of online
article about how to use JSDSI in addition to publishing the demo code
so it would be a little more clear for other java app developers.

I leave for Burning Man in two days, and then FOO Camp is three days
after I get back. I sort of don't think I'm going to have anything
ready to demo, but I'm still trying to make it happen. If I can get to
the point where I can complete an authorization/request circuit with a
couple of days left to spare then I might be able to build enough of
an example on top of that to at least demo the concept if not an
actual beta app.

Thanks in advance for any advice!

--
Dav Coleman
http://AkuAku.org/