Title: Re: [ebxml-msg] Authenticatio/Authorization on "pull" message
over a MPF.
Dale, Ric, everybody,
Here is in 9 lines my comments on this: First,
there are more than a dozen solutions out there to the problem we are trying to
tackle and I simply think that no solution can stand out among the crowd and
claim that it deserve to be standardized. If we have to pick one solution among
the possible ones, the only one that deserves to be standardized is a solution
that is based solely on SOAP headers such that these SOAP headers remain in the
message and are visible to the ebMS module even after the WSS module processed
them. Second, when the spec does not say anything about the authentication, the
default interpretation is that all the possible solutions out there are all possible
and are not prohibited by the spec. Third, HTTP basic auth does not have
anything special that makes it worth of being standardized. WSS Username token
is a lot better than HTTP auth as it has SOAP headers; however this is exactly
the solution that we first crafted in the spec and later it was removed because
it turned out to be a stupid solution. So now we are back to the beginning. If
we are going to standardize WSS Username Token as the way of doing things, this
still needs to be specified in details. Two alternatives are possible: (a) the
token resides inside the ebMS headers and is generated and processed only by
ebMS modules (in this case there is no <wss:Security> element wrapper,
only a reuse of WSS syntax and this is equivalent to the eb:AccessCode solution).
(b) the token resides in an external <wss:Security role=”ebms”>
element that contains only this token and nothing else and that the WSS module
is instructed to not touch that security element (because role attribute is “ebms”).
Hamid.
From: Ric Emery
[mailto:]
Sent: Friday, November 03, 2006
3:01 PM
To: Dale Moberg;
Subject: Re: [ebxml-msg]
Authenticatio/Authorization on "pull" message over a MPF.
I think mandating HTTP basic auth
and WSS Username token profile is a reasonable compromise solution. For many
ebMS MSHs it should be very easy to support both solutions. For other
distributed ebMS solutions, I suspect as you do, that something could be
kludged up. For the username token profile, if the MSH Vendor does not have an
easy way to pass authentication data from their WSS module to the ebMS module,
I can imagine the WSS module being bypassed. The WSS username token profile
headers could be dealt with directly in the ebMS module. The username token
profile is simple enough that relying on a third party library should not be
required.
-ric
On 11/1/06 6:36 PM, "Dale Moberg" <> wrote:
The problem as I understand it is
that we want to make certain at the “server” side that a request
for a message on a MPF is only honored if the requesting agent is authorized to
access that particular MPF. That is, having the request be authenticated as
from some party (data origin authentication) is insufficient. An authorization
“rule” needs be be consulted to check whether a request from that
authenticated identity is authorized to pull a message on the MPF.
That said, an additional constraint on solutions to the problem is that the
requesting party is possibly “PKI-challenged” so that strong
authentication approaches (involving signing of something) cannot be required.
Another constraint is that the desired solution must be implemented across all
(!) conformance profiles. An additional desired feature is that the solution be
independent of transfer protocol. Final design features want the solution to be
cleanly deployable across architectures involving many SOAP intermediaries in
the path.
My proposal is that both HTTP basic authentication and WSS Username token
profile authentication be mandated. HTTP basic auth because it is pervasive
(though transfer protocol dependent) and WSS Username because it is transfer
protocol. Both authentication approaches may have some risk when used without
TLS. What we say about MPF processing is, however, that it must check that the
identity available through some supported means of authentication be eligible
to pull messages from the MPF. Other mechanisms of authentication can be agreed
upon (via a PMode? or via a CPA) but in any case, the MPF supporting
service must do the check that identity is authorized to use resource MPF.
We should also run this proposal (or its refinement reached by this group) by
the end user audiences we have already consulted, and verify with them that the
approach meets their requirements.
Dale Moberg
As to the deployability across any arbitrary SOAP path, with any arbitrary
targeting of headers, and with unknown header augmentations and removals, I
suspect something can be kludged up to work. (Check the HTTP basic auth, add an
ad hoc authentication header, email it to the next hop, etc, etc, until
something that needs to check the MPF and identity map pulls off the identity
header, and does its check). However, I am not interested in trying to spec out
all the possible permutations personally.
