If the portlet is expected to “secure”
its actual data as you say, why do we need this flag to indicate that the
consumer must not map the data?
Especially if the data is encrypted, presumably
only viewable at the intended point of delivery, there is absolutely no need to
raise this flag. This is what I mean by using the lower levels of the stack.
I also think that allowing consumers to
decide what producer is securely connected (not defining it in the spec, as you
suggest by “social” security) is really equivalent to letting the
consumer decide which elements of the data are secure.
A good topic for discussion tomorrow…
From: Michael Freedman
Sent: Tuesday, December 21, 2004
Subject: Re: [wsrp] Issue #28:
Finally getting caught up on the discussions ... Nope, I think we will
have to do this in the protocol. I don't see anyway for it to occur in a lower
layer. The general problem I want to see solved is to allow a portlet to indicate/guarantee
that at least https security will be used to distribute this event and or
portions of its data [in mapped events] to other portlets. We need the
boolean in the description to help consumers to guide end-users by restricting
the list of portlets that can receive the event. Producers requiring
"true" transport level security including at the point it raises an
event is expected to encode those performBlockingInteraction urls using https.
However, we still want to support producers that use "social"
security -- such as having the consumer/producer inside a firewall and hence
need to separate the distribution requirement from the method of invocation.
To avoid the problems Yossi points out we need the specification to require/mean
that all events distributed as result of raising this event must be distributed
securely. I.e. once you raise an event and ask it be distributed securely
it and anything mapped from it, or any events raised as a consequence of its
distribution would have to be distributed securely. To avoid consumer
security holes where the consumer maps the value from an event into application
data and later distributes this unsecurely, the portlet would be expected to
"secure" its actual data -- i.e. its types would be opaque and it
likely is encrypted.
Finally, as to why we need this value in both Event and EventDescription I
think we need it because we don't require Events have EventDescriptions.
I.e. I can raise an Event I haven't told the consumer about.
Yossi Tamari wrote:
I think this brings out some of the
problems in this approach.
For example, your wording bellow can be
interpreted to say that the event data is secure, but the fact that the event
fired is not. Obviously this is not always the case.
Personally I think that for consumers that
manipulate the content of the event, there should not be a “must
not” or even “should not” statement, because somebody is
developing an “application” that understands the nature of the data
that he is receiving and sending, and it is up to that developer to integrate
the security considerations.
(An example of such use case would be a
raised event that contains a user name and email, where the user name does not
need security but his email does.)
For basic event consumers I would say that
even the fact that the event was raised should not be exposed on an insecure
Another question is what happens when a
consumer distributes a requiresSecureDistribution event on a secure channel to
another producer, which then (not knowing that this data is actually considered
secured) raises a non requiresSecureDistribution event containing parts of the
Ideally I would like use to drop this
field altogether and leave the security of any element in the SOAP message to
lower levels of the SOAP stack (WS-Policy?). I am not sure if this is currently
viable here. Any thoughts?
One area that is not reflected in the current draft, nor considered in
Andre's alternate proposal, is that the resulting security level needed for
distributing an event applies not only to directly distributing the event as
the portlet has generated it, but also becomes the minimum for the distribution
of any information contained within the event which the Consumer might
distribute in some other event it composes. I'll add language to this effect to
draft 04 and would also plan to include it if the mechanism is changed to
I have opened issue #28 for this topic. Basically we have two proposals in
front of us:
1. Have requiresSecureDistribution fields on both the EventDescription and Event
structures. This presumes that non-secure distribution is allowed unless the
portlet has said otherwise using these flags.
2. Have authorizedNonSecureDistribution field on just the Event structure. This
requires that the Consumer distribute events in as secure manner as it received
them unless this field has been set to true (default = false).
What do people think of these two choices?
The markup related fields you mention speak more about user agent to consumer
communications than WSRP protocol security to me. My concern still is that we
are adding security protocol (which we usually tend to avoid) and that this
could lead to problems for 2.0 implementation and continuing down the road
(when we have message based security and policy negotiation). If we really need
the functionality you describe below would the following not be simpler?
AuthorizeInsecureRedistribution : Boolean flag on Event objects (default
false). If a consumer receives an event with this flag set to true and the
consumer can verify that the flag is as the producer set it (i.e. was not
tampered with, for example because the event was signed by the producer and the
consumer verified the signature or was received over a secure end-to-end
transport) then the event MAY be re-distributed to other portlets over an
insecure communications channel. Such explicit downgrading of security by a
producer/portlet should be used with care. Note, consumers may redistribute an
event received on an insecure channel regardless of the value of this flag.
[The event description flag would go.]
Sorry keep laboring the point but security is extremely important to get right.
From: Rich Thompson [mailto:firstname.lastname@example.org]
Sent: 15 December 2004 18:08
Subject: RE: [wsrp] EventDescription.requiresSecureDistribution
It was commented at the F2F that much as we have these fields relative to
markup, we would need them for events. Without much discussion, everyone agreed
and my notes say to add the fields. I think the following may provide a base
use case for them:
A Consumer incorporates a pair of remote portlets (P1 & P2) on a page
P1: The Producer only offers unsecure ports (e.g. http)
P2: The Producer only offers secure ports (e.g. https)
1. If P2 generates an event that does not require secure communication during
distribution, how to tell the Consumer?
2. If P1 generates an event that it determines does need secure communications
and determines it can securely send it to the Consumer (either by network
topology or message security), can it insist that it only be distributed in a
Obviously a Producer offering both types of ports just complicates the logic
(but not the fundamental questions) by throwing in the question of whether of
not the transport layer will make the current communications with the Consumer
secure. Message level security just adds another equivalent wrinkle to the
logic side of things.
I think both of the above situations will happen and that the protocol should
make it easy to signal to the Consumer the security concerns related to
distributing an event. I suppose we could remove the field from the event
description and require on the event, but this would move valuable information
from design time to runtime.
A producer that wishes to return an event securely can not publish a http
binding (i.e. only an https binding so that SOAP responses are secured) if transport
level security is to be used, or use message level security for responses.
Given we start from this position, is it not more a question of the producer
possibly granting the consumer the right to forward an event on a less secure
channel? How useful is such a feature as opposed to just mandating that a
securely returned event be always forwarded securely? I think the end goal
should be for end to end security to be used to secure the event payload so do
we really need these flags?
From: Rich Thompson [mailto:email@example.com]
Sent: 15 December 2004 15:07
Subject: Re: [wsrp] EventDescription.requiresSecureDistribution
Rereading this on the OASIS distribution reminded why the event field did not
have a default specified in the schema ... its default is whatever was
specified in the EventDescription.
Good point on the possibility of tampering ... I'll add a sentence in section 9
of draft 04 to point this out.
The reason the field exists in both places is that some events will always
require secure distribution and some will only require it when sensitive
information is being carried in the payload (i.e. dynamic payload contents).
We deliberately named the equivalent fields in v1 as simply requiring security.
This allows evolving security standards to be used as they become supported.
Thanks for catching the .xsd overlook of the default value. Has been updated
relative to the next version.
We should note that basing security decisions
only makes sense if the EventDescription was itself
securely. The threat here being
do not see why we would want to duplicate
flag in the Event type itself, even if we include it in the
consumer should either use (securely determined) metadata to
security level for event transmission or use the same
security level at which an event was received to re-distribute the
it be simpler to use the same rule as for getMarkup to distribute all events?
i.e. If a producer publishes a secure binding (i.e.
then the consumer should make use of it? Or, better, provide
encourage means for the event data to be signed/encrypted by sending
case, the Event.requiresSecure(Re)Distribution
declaration XML schema could do with a
default="false" to match the EventDescription convention.