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.
-Mike-
Yossi Tamari wrote:
Hi Rich,
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 channel.
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 data?
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?
Yossi.
From: Rich Thompson [mailto:]
Sent: Thursday, December
16, 2004 4:31 PM
To:
Subject: RE: [wsrp] Issue
#28: Replace EventDescription.requiresSecureDistribution?
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 Andre's proposal.
Rich
Rich
Thompson/Watson/IBM@IBMUS
12/16/2004 08:29 AM
To
cc
Subject
RE: [wsrp] Issue #28:
Replace EventDescription.requiresSecureDistribution?
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?
Rich
Andre
Kramer <>
12/16/2004 04:47 AM
To
cc
Subject
RE: [wsrp] EventDescription.requiresSecureDistribution
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.
Regards,
Andre
From: Rich Thompson [mailto:]
Sent: 15 December 2004 18:08
To:
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
where:
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 secure manner?
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.
Rich
Andre
Kramer <>
12/15/2004 11:52 AM
To
cc
Subject
RE: [wsrp] EventDescription.requiresSecureDistribution
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?
Regards,
Andre
From: Rich Thompson [mailto:]
Sent: 15 December 2004 15:07
To:
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.
Rich
Rich
Thompson/Watson/IBM@IBMUS
12/15/2004 09:20 AM
To
cc
Subject
Re: [wsrp] EventDescription.requiresSecureDistribution
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.
Rich
Andre
Kramer <>
12/10/2004 05:15 AM
To
cc
Subject
[wsrp] EventDescription.requiresSecureDistribution
We should note that basing security
decisions on EventDescription.requiresSecureDistribution
only makes sense if the EventDescription was itself
was retrieved securely.
The threat here being Tampering.
I do not see why we would want to
duplicate the flag in the Event
type itself, even if we include
it in the event metadata. IMHO A consumer should either use
(securely determined) metadata to determine the security level
for event transmission
or use the same security level
at which an event was received
to re-distribute the event (Event.RequiresSecureRedistribution?).
Would 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. SSL) then the consumer should
make use of it? Or, better, provide and encourage
means for the event data to
be signed/encrypted by sending portlets?
Regards,
Andre
PS. In any case,
the Event.requiresSecure(Re)Distribution
declaration XML schema could do with a default="false"
to match the EventDescription convention.
