- From: Harry Halpin <hhalpin@w3.org>
- Date: Tue, 16 Aug 2016 20:56:33 +0200
- To: Mark Watson <watsonm@netflix.com>
- Cc: "public-html-media@w3.org" <public-html-media@w3.org>
- Message-ID: <f587671b-3f7d-9833-f58d-ec7cf7349de3@w3.org>
On 08/16/2016 08:52 PM, Mark Watson wrote:
>
>
> On Tue, Aug 16, 2016 at 11:41 AM, Harry Halpin <hhalpin@w3.org
> <mailto:hhalpin@w3.org>> wrote:
>
>
>
> On 08/16/2016 07:51 PM, David Singer wrote:
> > I think you are confusing DRM and EME. They are not the same.
>
> Actually, as pointed out by Ruben's email I just read, clearKey would
> count as DRM and be covered by the DMCA - and is part of the EME
> spec. I
> hadn't thought that through earlier but it's a very good point. The
> addition of clearKey would likely made EME itself covered by the DMCA.
>
>
> IANAL, but I think a case could be made that Clear Key is not an
> "effective" protection measure, since the key is available, well, in
> the clear. Certainly, no one would call it a "DRM".
I think whether or not it is an 'effective' protection measure is
separable from whether or not its covered by the DMCA. That's a legal
question - if Netflix or any other company with a legal dept. (or W3C)
would like to answer that question, I believe it would be of interest.
The question Ruben provoked should probably be answered before the spec
goes to Rec.
>
>
>
>
> Regardless of the clearKey specifics, EME exists to enable access
> to a
> CDM in a manner standardized across browser, and is thus part of a
> DRM-enabled system.
>
> >
> > EME can be shipped as an intrinsic part of the browser. The user
> will be asked to install XYZ DRM by any operating system I can
> think of. If they agree and consent to that, you’re asking for an
> extra step “do you also agree to enable access to this module from
> your browser?’, when in all likelihood that is the very reason
> they chose to install it.
>
> However, the OS is outside control of the W3C and does not have any
> standards. Thus, we cannot guarantee there will be agreement and
> consent. So I don't think you can just shove this step to the OS,
> but it
> should be required by the spec and done in *browser*.
> >
> > It makes no sense to me. It doesn’t deal with any risk you have
> so far enumerated.
>
> I would suggest just revisitng the Wikpedia page and following the
> large
> number of links. Note they go beyond security research, including
> problems with innovation. Accessibility concerns have also been
> raised.
> These are not new issues, but well-known. Which is why Steve Jobs
> took a
> stand against DRM:
>
> https://www.engadget.com/2007/02/06/a-letter-from-steve-jobs-on-drm-lets-get-rid-of-it/
> <https://www.engadget.com/2007/02/06/a-letter-from-steve-jobs-on-drm-lets-get-rid-of-it/>
>
> >
> > That security researchers haven’t assessed XYZ DRM is a risk to
> you is not the same as whether the EME implementation is a risk to
> you.
>
> As EME opens the door for using (and MSE possibly installs) XYZ
> DRM, yes
> it is.
>
> >
> > I’m sorry to press on this, but we need to be clear, because
> risk mitigation is based in being really clear what the risk is.
> At the moment, I don’t see any risk in parts of the browser that
> are the *interface* to modules that the user may choose to load.
> They might be there, but conflating the risk of the module itself
> with the interface is not helping get clarity.
>
> If your argument is that DRM is not a risk to end-users, then there is
> widespread disagreement from the independent security and legal
> community on your point as evidenced by both Wikipedia and various
> papers by well-respected acaemics that focussed on users [1] .
> From my
> individual perspective, it seems the only people who argue that DRM is
> not a problem for end-users is people whose job it is to implement
> DRM,
> groups whose income depends on revenue from DRM implementers, and the
> various groups that stand to make profit from DRM. Thus, it is unclear
> if any of those viewpoints are sufficiently neutral to address the
> harm
> to users that DRM could cause. Furthermore, EME is both a DRM system
> due to clearKey and an interface to specific CDMs, so the concerns
> around DRM naturally encompass EME.
>
> cheers,
> harry
>
> [1] http://dl.acm.org/citation.cfm?id=947391
> <http://dl.acm.org/citation.cfm?id=947391>
>
> >
> >
> >> On Aug 16, 2016, at 10:36 , Harry Halpin <hhalpin@w3.org
> <mailto:hhalpin@w3.org>> wrote:
> >>
> >>
> >>
> >> On 08/16/2016 07:28 PM, David Singer wrote:
> >>>> On Aug 16, 2016, at 10:22 , Harry Halpin <hhalpin@w3.org
> <mailto:hhalpin@w3.org>> wrote:
> >>>>
> >>>>
> >>>>
> >>>> On 08/16/2016 06:35 PM, David Singer wrote:
> >>>>> I think you’ll need to explain why the choice of how much,
> and how, the user is warned, needs to be made by you/us, and not
> by the browser maker. You also haven’t given details of the ‘user
> harm’ you talk about for EME itself.
> >>>> The details of 'user harm' are adequately explained by the
> concerns over
> >>>> the DMCA and the use of DRM that have been well-documented
> elsewhere
> >>>> [1].
> >>> No, those criticisms were almost exclusively focused on the
> risk to security researchers. Not one of the sub-headings you link
> to appears to apply to users. Current politics notwithstanding,
> repeatedly stating something doesn’t intrinsically make it true.
> >> I don't agree. Insofar as security researchers cannot audit the
> >> security of DRM systems, then it is *users* who will face any
> harm due
> >> to the lack of security audits. That is a unique feature of DRM
> that EME
> >> enables. EME can also, due to clearkey, be considered a
> DMCA-compliant
> >> system itself (i.e. clearKey's Key System is equivalent to a CDM).
> >>
> >>>> Any installation or use of software that is compliant with
> the DMCA
> >>>> can be considered a risk to users and security researchers as
> is noted
> >>>> on WIkipedia [1].
> >>> Users and security researchers are not the same people.
> >> See above.
> >>
> >>>> Although the FO is filed as an individual, one task of W3C is
> to assure
> >>>> there is representation of the interest of users and to
> ensure the Web
> >>>> is secure.
> >>> Sure, but you need to say what the *user* harm is.
> >> If there is a part of a browser that makes security research
> difficult
> >> and possibly illegal, then that part of the browser is rather
> >> self-evidently dangerous to end-users. While I appreciate the
> effort,
> >> sandboxing may help but there is no such thing as a perfect
> sandbox.
> >>
> >>>> So, I think the decision should be made by the Working Group
> >>>> with the best interests of users in mind, not just the
> browser makers.
> >>>> While you can consider 'off by default' to be unreasonable, I
> think if
> >>>> one takes that this same approach has been adopted by similarly
> >>>> controversial APIs (Geolocation API), I think it's quite
> reasonable.
> >>>>
> >>>> cheers,
> >>>> harry
> >>>>
> >>>> [1]
> >>>>
> https://en.wikipedia.org/wiki/Digital_Millennium_Copyright_Act#Criticisms
> <https://en.wikipedia.org/wiki/Digital_Millennium_Copyright_Act#Criticisms>
> >>>>
> >>>>>> On Aug 16, 2016, at 4:28 , Harry Halpin <hhalpin@w3.org
> <mailto:hhalpin@w3.org>> wrote:
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> On 08/13/2016 05:05 PM, Paul Cotton wrote:
> >>>>>>> Note that I am responding to an email and proposal from
> Harry from earlier in this thread.
> >>>>>>>
> https://lists.w3.org/Archives/Public/public-html-media/2016Aug/0005.html
> <https://lists.w3.org/Archives/Public/public-html-media/2016Aug/0005.html>
> >>>>>>>
> >>>>>>>> The text I would add to the EME spec would be similar:
> >>>>>>>> "A conforming implementation of this specification MUST
> ensure that this
> >>>>>>>> API cannot be used without the user's express permission
> due to the
> >>>>>>>> inherent risks in the activation of a CDM in a user
> agent. The API MUST
> >>>>>>>> be disabled by default, and should only be activated when
> the user gives
> >>>>>>>> express consent and is fully informed on a per-origin basis."
> >>>>>>> This request would appear to be (at least partially)
> covered by the existing text in the EME CR:
> >>>>>>>
> http://www.w3.org/TR/encrypted-media/#navigator-extension-requestmediakeysystemaccess
> <http://www.w3.org/TR/encrypted-media/#navigator-extension-requestmediakeysystemaccess>
> >>>>>>>
> >>>>>>> 3.1.1 Methods
> >>>>>>> requestMediaKeySystemAccess
> >>>>>>> Note
> >>>>>>>
> >>>>>>> Calling this method may have user-visible effects,
> including requests for user consent. This method should only be
> called when the author intends to create and use a MediaKeys
> object with the provided configuration.
> >>>>>>> Requests access to the specified Key System. When
> supportedConfigurations is specified, the configuration specified
> by at least one of its elements must be supported. The resulting
> MediaKeySystemAccess will correspond to the first such element.
> >>>>>>> Any permission checks or user interaction, such as a
> prompt, MUST be performed before resolving the promise.
> >>>>>>> Were you aware of this text in the EME specification? Can
> you live with the current text since changing this text to be
> normative and changing it to a MUST (I believe) would be a
> “breaking change” and would require that we re-publish another EME CR?
> >>>>>>>
> >>>>>>> /paulc
> >>>>>>> HME WG Chair
> >>>>>> Paul,
> >>>>>>
> >>>>>> Thanks for noting 'use-visible effects' but it does not
> either explicitly 1) require a user-visible effect for fully
> informing the user" and "gaining their consent" as well "turning
> off EME by default". Simply put, the text you are noting says MAY
> have user-visible effects and as so is too weak to include in a
> test-suite or support EME being off by default. So, it does not
> cover my objection, which normatively requires much stronger text,
> including "off by default". So, no I can't live with that text and
> require the change (or a semantically equivalent one) that I
> suggest in the github repo and e-mail list:
> >>>>>>
> >>>>>> https://github.com/w3c/encrypted-media/issues/304
> <https://github.com/w3c/encrypted-media/issues/304>
> >>>>>>
> >>>>>> Thus, my formal objection still stands.
> >>>>>>
> >>>>>> cheers,
> >>>>>> harry
> >>>>>>
> >>>>>>> From: Harry Halpin [mailto:hhalpin@w3.org
> <mailto:hhalpin@w3.org>]
> >>>>>>> Sent: Tuesday, August 2, 2016 5:00 AM
> >>>>>>> To: public-html-media@w3.org <mailto:public-html-media@w3.org>
> >>>>>>> Subject: Re: Formal objection to Encrypted Media
> Extensions progressing to Proposed Recommendation without greater
> user protection
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>> On 08/02/2016 03:00 AM, Paul Cotton wrote:
> >>>>>>>> An individual who registers a Formal Objection should
> cite technical arguments and propose changes that would remove the
> Formal Objection;
> >>>>>>>
> http://www.w3.org/2015/Process-20150901/#WGArchiveMinorityViews
> <http://www.w3.org/2015/Process-20150901/#WGArchiveMinorityViews>
> >>>>>>>
> >>>>>>> Before I record your formal objection at [1] I would like
> to ensure that your “proposed change” for your objection is
> understood.
> >>>>>>>> There is prior art in HTML for similarly powerful and
> privacy-invasive features such as the Geolocation API [4]. Thus,
> there should be no procedural problem in requiring user consent
> and disabling EME by default in all browsers.
> >>>>>>> The reference you provide as a “prior art” precedent in
> [4] is in a non-normative section of Geolocation API and it does
> NOT disable the Geolocation API by default. Can you explain why
> you think this reference is useful here? Are you suggesting
> similar text be added to EME? If so could you suggest exact text
> that would remove your formal objection?
> >>>>>>>
> >>>>>>> The exact phrasing is " A conforming implementation of
> this specification must provide a mechanism that protects the
> user's privacy and this mechanism should ensure that no location
> information is made available through this API without the user's
> express permission"
> >>>>>>>
> >>>>>>> To clarify, I agree that the spec should have used
> capitalization: " A conforming implementation of this
> specification MUST provide a mechanism that protects the user's
> privacy and this mechanism should ensure that no location
> information is made available through this API without the user's
> express permission."
> >>>>>>>
> >>>>>>> However, I do believe that all browsers *do* indeed ask
> for user consent before using the Geolocation API and that it is
> disabled by default, which is clear prior art for EME. This is
> indeed the case on the browsers I use, but if others activate
> Geolocation API without user consent, please do inform me, as I
> don't use Microsoft products.
> >>>>>>>
> >>>>>>> The text I would add to the EME spec would be similar:
> >>>>>>>
> >>>>>>> "A conforming implementation of this specification MUST
> ensure that this API cannot be used without the user's express
> permission due to the inherent risks in the activation of a CDM in
> a user agent. The API MUST be disabled by default, and should only
> be activated when the user gives express consent and is fully
> informed on a per-origin basis."
> >>>>>>>
> >>>>>>> Given there is already a place where user consent MUST be
> asked in the EME spec (" User agents must ensure that users are
> fully informed and/or give explicit consent before Distinctive
> Identifier(s) are exposed, such as in messages from the Key System
> implementation"), there is no reason why this MUST can't be
> broadened. I would also remove the "or." The user must be fully
> informed AND give explicit consent.
> >>>>>>>
> >>>>>>> Furthermore, given this normative, testing for express
> user consent on a per-origin basis should be part of the test-suite.
> >>>>>>>
> >>>>>>> cheers,
> >>>>>>> harry
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>> /paulc
> >>>>>>> HME WG Chair
> >>>>>>>
> >>>>>>> [1]
> https://dev.w3.org/html5/status/formal-objection-status.html
> <https://dev.w3.org/html5/status/formal-objection-status.html>
> >>>>>>>
> >>>>>>> From: Harry Halpin [mailto:hhalpin@w3.org
> <mailto:hhalpin@w3.org>]
> >>>>>>> Sent: Monday, August 1, 2016 6:42 PM
> >>>>>>> To: public-html-media@w3.org <mailto:public-html-media@w3.org>
> >>>>>>> Subject: Formal objection to Encrypted Media Extensions
> progressing to Proposed Recommendation without greater user protection
> >>>>>>>
> >>>>>>> [Note this is a formal objection as an individual in a
> private capacity, not on behalf of my organization]
> >>>>>>>
> >>>>>>> I'd like to fill a formal objection against Encrypted
> Media Extensions progressing to Proposed Recommendation status
> without adequate protection for users.
> >>>>>>>
> >>>>>>> I believe that this work is so problematic given the
> well-known and well-documented problems with DRM, it should not
> happen as a standard at all at W3C. That being said, for reasons
> which I do not agree with and hope he reconsiders, the Director
> has approved both the scope of the charter and the move of the
> Working Draft to Candidate Recommendation.
> >>>>>>>
> >>>>>>> If it does happen, then it seems given the well-documented
> problems, some harm mitigation should be pursued. The security
> research community has broad support for the EFF covenant being a
> normative requirement [1]. However, it appears consensus is not
> forthcoming on either EME itself or the EFF covenant, with the
> Technology and Policy IG also failing to gain any consensus for
> even further discussion (as it failed to even get chartered).
> >>>>>>>
> >>>>>>> To myself, the danger of EME is that over the last year
> suddenly over millions of people had a content decryption module
> installed without their explicit consent on their computer. For
> many users, such as those of Firefox, the DCM was installed via a
> silent update they had no control over. Such a content decryption
> module can serve as both a technical security risk, as it puts a
> highly privileged process in the user's computer outside their
> direct control by design, and as a legal risk subjects any
> inspection of the DRM-enabled system on their computer due to the
> anti-circumvention provision of the DMCA or local equivalent.
> Thus, regardless of whether or not one agrees with EME, it seems
> the *least* the W3C should do is warn the user about the
> installation and activation of a CDM on their machine - and that
> the CDM should not be installed and EME should not be activated
> without explicit user consent. Thus, in all configurations, EME
> should be *de-activated by default.*
> >>>>>>>
> >>>>>>> There is prior art in HTML for similarly powerful and
> privacy-invasive features such as the Geolocation API [4]. Thus,
> there should be no procedural problem in requiring user consent
> and disabling EME by default in all browsers. While it can be
> argued many users will want to watch protected videos and will
> turn them on, just as many users will want to use Google Maps with
> Geolocation APIs, there does not seem to be a reasonable case for
> having such
> >>>>>>> powerful and possibly dangerous features enabled by default.
> >>>>>>>
> >>>>>>> Current language in the spec is so weak as it may not be
> enforced and so EME does not have to be disabled by default: "
> User Agents have some flexibility to determine whether consent is
> required for a specific configuration and whether such consent may
> also apply to other configurations. For example, consent to one
> configuration may also imply consent for less powerful, more
> restricted configurations. Equally, a denial of consent for one
> configuration may imply denial of consent for more powerful, less
> restricted configurations."
> >>>>>>>
> >>>>>>> The only place where the spec [5] makes normative
> statements around consent, but due to how DRM (i.e. Key Systems)
> are designed, it is unclear how the user agent should interpret
> these statements
> >>>>>>>
> >>>>>>> "If a user agent chooses to support a Key System
> implementation that cannot be sufficiently sandboxed or otherwise
> secured, the user agent should ensure that users are fully
> informed and/or give explicit consent before loading or invoking it."
> >>>>>>>
> >>>>>>> "User Agents should ensure that users are fully informed
> and/or give explicit consent before a Key System that presents
> security concerns that are greater than other user agent features
> (e.g. DOM content) may be accessed by an origin..."
> >>>>>>>
> >>>>>>> " User agents must ensure that users are fully informed
> and/or give explicit consent before Distinctive Identifier(s) are
> exposed, such as in messages from the Key System implementation."
> >>>>>>>
> >>>>>>> Although these statements show some progress towards
> trying to mitigate the dangers of DRM, given that DRM systems work
> in conjunction with anti-circumvention legislation that prevents a
> developer from knowing whether or not they can sufficiently
> sandboxed (or 'otherwise secured') and whether a Distinctive
> Identifier is used by the DRM system, so the use of EME will
> *always* present security concerns that are greater than the rest
> of the user agent features involving the Open Web Platform.
> >>>>>>>
> >>>>>>> Is the Working Group amendable to having EME and
> associated DRM systems (i.e. "Key Systems") *normatively* disabled
> by default in order to protect users?
> >>>>>>>
> >>>>>>> cheers,
> >>>>>>> harry
> >>>>>>>
> >>>>>>> [1]
> https://www.eff.org/deeplinks/2016/03/security-researchers-tell-w3c-protect-researchers-who-investigate-browsers
> <https://www.eff.org/deeplinks/2016/03/security-researchers-tell-w3c-protect-researchers-who-investigate-browsers>
> >>>>>>> [2]
> https://en.wikipedia.org/wiki/Digital_rights_management#Opposition_to_DRM
> <https://en.wikipedia.org/wiki/Digital_rights_management#Opposition_to_DRM>
> >>>>>>> [3]
> https://en.wikipedia.org/wiki/Digital_rights_management#Shortcomings
> <https://en.wikipedia.org/wiki/Digital_rights_management#Shortcomings>
> >>>>>>> [4]
> https://www.w3.org/TR/geolocation-API/#implementation_considerations
> <https://www.w3.org/TR/geolocation-API/#implementation_considerations>
> >>>>>>> [5] https://w3c.github.io/encrypted-media/
> <https://w3c.github.io/encrypted-media/>
> >>>>>>>
> >>>>> David Singer
> >>>>> Manager, Software Standards, Apple Inc.
> >>>>>
> >>>>
> >>> David Singer
> >>> Manager, Software Standards, Apple Inc.
> >>>
> > David Singer
> > Manager, Software Standards, Apple Inc.
> >
> >
>
>
>
>
Received on Tuesday, 16 August 2016 18:56:52 UTC