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Part 1: Ownership and Contracts


From: Marcus Brinkmann
Subject: Part 1: Ownership and Contracts
Date: Wed, 03 May 2006 10:52:08 +0200
User-agent: Wanderlust/2.14.0 (Africa) SEMI/1.14.6 (Maruoka) FLIM/1.14.7 (Sanjō) APEL/10.6 Emacs/21.4 (i486-pc-linux-gnu) MULE/5.0 (SAKAKI)

Hi,

Part 1: Ownership And Contracts
-------------------------------

This is the first in a series of notes that will serve to formulate my
position from ground-up.  The way will not be straight-forward.  I can
not give you one particular, technical argument that addresses all my
concerns.  Instead, the evaluation involves a step of personal
judgement (but only one).  In this note, I will explain why I believe
that this is necessarily the case, what this step is and what my
stance on it is.

This mail took me 5 hours to write, which means 1.5 lines per minute.
It contains only a tiny part of my argument.  I hope that this removes
any doubts about my sincerity to address all issues, but also makes
apparent the technical constraints in doing so "immediately", as has
been requested from me several times.  I have to ask for patience.  As
everybody else, I am doing this in my spare time.

Let me jump right in at the technical level: I claim that every
relationship between two processes falls into one of four categories.
These four coarse categories provide a differentiation that is
sufficient for my argument:


Process Relationship Categories

0. It is not possible for the processes to communicate via direct IPC.

In all other categories, it is possible for the processes to
communicate via direct IPC, because one of the processes, let me call
it process A, has a capability to the other process, let me call it B.

1. The collective authority of process B, immediately[1] after the
time it was instantiated, is necessarily a strict subset of the
collective authority hold by process A at that time.

[1] See my challenge-email to find a definition of the window of time
that gives meaning to the word "immediately" in the case where process
B is instantiated indirectly or directly because of an action in
process A.  If process B is instantiated independent of process A,
just assume that the collective authority hold by process A is the
empty set.

2. The set of collective authority of process B, immediately after the
time it was instantiated, minus the collective authority of process A
(if it existed), is necessarily not empty.  Some of the capabilities
in this non-empty set provide the ability to write-out.

3. The set of collective authority of process B, immediately after the
time it was instantiated, minus the collective authority of process A
(if it existed), is necessarily not empty.  None of the capabilities
in this non-empty set provide the ability to write-out.

This categorization does not say anything about encapsulation.
However, it is to be understood from the description that in category
0, 2 and 3, process B is encapsulated.  If it were not, the collective
authority that is hold by A would include the authority of B by
transition.  In category 1, it is to be understood that process B, in
principle, can not be successfully encapsulated (to see this, pay
attention to the fact that process A could pre-arrange its authority
so that no capability it has provides the possibility for
encapsulation).

This categories provide a complete categorization for two important
system structures: The EROS/Coyotos model, which relies on categories
0, 2 and 3, while making category 1 possible.  And my recursive system
structure model, which relies on categories 0, 1, and 2, but rejects 3.


Agenda

This provides the basis for a goal-based analysis.  The agenda can be:

1) It has to be demonstrated that the goals of the Hurd can be met by
relying on the process relationships described by 0, 1 and 2.  This of
course must include an analysis of the goals of the Hurd.

2) It is useful to reason about the rejection of category 3.  What do
we lose by omitting it?  What goals can not be achieved by the Hurd if
it rejects category 3?

This sets the background.  I will start with the second item on the
list, and then work my way up.  It would not be unreasonable to do it
the other way around: I could state the goals of the Hurd, then
demonstrate that we can achieve them by using the model I described
earlier, and then look at the interaction with category 3
relationships.  This would be the straighter way.  However, a
discussion of the goals of the Hurd can be easier followed if the
background is set.  So, let me finish this note with some general
arguments about the properties of category 3, and what the factors can
be that determine how you think about it.


Encapsulation and Confinement

What is the exact nature of the relationship between process A and
process B, where communication can (and does) occur, but process B is
both encapsulated and confined?  To discuss this, we have to define
what we mean by the nature of process relationships.  Two concepts
come into my mind: Ownership and contracts.  What do these words mean?

In the course of the discussion, I will make use of citations from
Hegel's Philosophy of Right.  I am not relying on his argumentation,
it is just a convenient source for some definitions, from which I want
to work.


Ownership

Ownership is not a complicated concept.  You can look it up in
encyclopedias or dictionaries, or you can study philosophy.  Hegel
defines ownership this way (Paragraph 61):

"Since the substance of the thing which is my property is, if we take
 the thing by itself, its externality, i.e. its non-substantiality ---
 in contrast with me it is not an end in itself (see § 42) and since
 in my use or employment of it this externality is realised, it
 follows that my full use or employment of a thing is the thing in its
 entirety, so that if I have the full use of the thing I am its
 owner. Over and above the entirety of its use, there is nothing left
 of the thing which could be the property of another."

A shorter definition is that ownership is the exclusive right of a
person to possess, use and dispose of a thing.  Note that the right
must be exclusive.  It must also be complete.  Also note that
ownership refers to human beings, not things.  Things can not own
other things.  Paragraph 42 in Hegel's work defines:

"What is immediately different from free mind is that which, both for
 mind and in itself, is the external pure and simple, a thing,
 something not free, not personal, without rights."


Contracts

Hegel describes the transition from ownership to contracts in
paragraph 71 this way:

"One aspect of property is that it is an existent as an external
 thing, and in this respect property exists for other external things
 and is connected with their necessity and contingency. But it is also
 an existent as an embodiment of the will, and from this point of view
 the 'other' for which it exists can only be the will of another
 person. This relation of will to will is the true and proper ground in
 which freedom is existent. --- The sphere of contract is made up of
 this mediation whereby I hold property not merely by means of a thing
 and my subjective will, but by means of another person's will as well
 and so hold it in virtue of my participation in a common will."

A contract is thus an agreement among agents to hold a property by
means of a common will.


Mediating Actors

In the case of confinement and encapsulation, there are not just two
agents engaging in a contract, there are three (at least).  There must
be three, because encapsulation and confinement means that neither the
party that is encapsulated, nor the party that is confined comes to
hold the other parties property.  So, there must be a third agent
which does hold both parties property, and which implements the common
will of the participants.

To find this agent, we just have to look for somebody who comes to
hold the other parties property.  In computer systems without "trusted
computing" components, this is the owner of the machine (and/or the
system administrator).  In computer systems with "trusted computing"
components, the mediating agent are the people or companies designing
and building the "trusted computing" hardware.

In either case, the mediating agent uses tools to implement the common
will.  In either case, the mediating agent has, not exclusive, but
still quite complete ownership over the property that is part of the
contract (possession, use and disposal).  In either case,
implementation of the common will depends on the well-behaviour of the
mediating agent.


Contract Requires Consent

If the mediating agent is supposed to implement the common will of the
participants in a contract, it needs to know what the common will is.
If a participant wants to engage in a contract, it needs to know what
the contract means before the participant can make a proper judgement
about participation.

In the process of entering a contract, you are giving up, at least
temporarily, possession of a thing you own.  This is why entering a
contract requires careful consideration and explicit consent.


Contracts Are Not Private

I can not make the transition here from the rights of individuals to
the structure and legitimation of civil societies.  This is the
subject matter of state philosophy.  However, it suffices to say that
the universal rights of individuals find (often, not always)
expression in the laws of the civil society, and that it is civil
society which is bestowed to resolve conflicts between the perceived
particular rights of individuals.

Because civil societies exist, and we live in them, and contracts are
fundamental to the function of a society, every society has extensive
and complex laws about how contracts are made, and what they can
entail, and what their limitations are.  The German Civil Code
contains 2385 articles on 433 pages, and this is only one of the many
laws that has something to say about the matter.  There are other laws
specific to contractual labor, anti-trust, publicly traded companies,
publications, etc etc.


A Matter Of Judgement

It is now appropriate to look again at the proposed system structures
in their extremes (there are shades of gray, but they have not been
seriously discussed so far).

In my model, the computer remains the property of its owner.  This
property right is strongly protected.  The system will not allow, by
default, operations that let the owner unintentionally enter into a
contract between two parties.  Any such contract requires explicit
consent.  It also requires, every time that a contract is made, to
explicitly choose the mediator and scope of the contract.  In other
words, the owner must be explicit about his particular will that
should be part of the common will of the contract.

In the EROS/Coyotos model employing "trusted computing", only part of
the computer is the property of the owner.  Another part of the
computer is owned by the manufacturer of the "trusted computing"
component.  The system will, by design, perpetually give away
possession of parts of the computer to other agents, by engaging
constantly in contracts with them.  The nature of these contracts is
built firmly into the system structure: The mediator is always the
agent that designed and implemented the "trusted computing" component.
The default "common will" is to alienate all rights to the property,
except the right to destroy it.

These seem to me the only serious proposals.  I recognize that my
model makes it harder for people to engage into contracts when they
want to.  In my opinion, this is justified: Negotiating and
implementing a contract is a fundamental process that can not be
overly simplified.  In fact, in any serious business, developing the
contracts between collaborating agents is a very serious and essential
part of the process.  Business holders are acutely aware of the risks
involved in engaging into a contract, and spent significant personnel
and financial resources to limit their risks.

There may be, in principle, a system that makes it convenient for
users to engage in standard contracts selectively, explicitely and
safely.  For this, however, the mechanisms involved must allow for a
broad range of expressions that reflects the structure of the existing
society, and the user must be able to decide if the contract actually
reflects the common will of the involved agents.  This is far beyond
what we can technically achieve, at least today, maybe forever.


On The Non-Technicality Of The Choice

Currently, we only know about the two possible extreme positions
described above.  There is an outstanding description of the
properties of my model, and how they can be achieved.  However, my
claim is that the choice between these two options can not be made on
technical grounds.  Each system is self-consistent and provides an
adequate solution to the task that it tries to solve.

The choice therefore comes down to a personal preference, which may
either be based on personal needs, or on a speculation on the future.

However, let me raise some cautions that illustrate why I have made my
choice the way I did.  These cautions do not constitute an exhaustive
list of my arguments.  It is not necessary for me to give an
exhaustive list.  In the end, what system one would prefer to use is a
personal decision that everybody has to make on their own grounds.


On The Effect Of Perpetual Alienation

Hegel remarks on the effect of perpetual alienation (my terminology)
(paragraph 67):

"Single products of my particular physical and mental skill and of my
 power to act I can alienate to someone else and I can give him the use
 of my abilities for a restricted period, because, on the strength of
 this restriction, my abilities acquire an external relation to the
 totality and universality of my being. By alienating the whole of my
 time, as crystallised in my work, and everything I produced, I would
 be making into another's property the substance of my being, my
 universal activity and actuality, my personality."

He then continues to add a comparison to the nature of being a slave:

"The distinction here explained is that between a slave and a modern
 domestic servant or day-labourer. The Athenian slave perhaps had an
 easier occupation and more intellectual work than is usually the case
 with our servants, but he was still a slave, because he bad alienated
 to his master the whole range of his activity."

It is undisputed (I hope) that computers occupy more and more of our
personal life.  By doing so, they start to embody significant parts of
our personality.  We, as domain experts, are miles ahead of the
general public in this regard, and it is our obligation to foresee
such developments.  By losing control over our computers, we risk
losing the ability to act universally.  This finds correspondence in
the risk of losing general-purpose computers to TiVo-ized locked down
embedded systems.


Passive Defense Is Not Sufficient

The passive defense against this risk is not sufficient.  You may hold
the opinion that the "trusted computing" component is optional.  The
machine owner can switch it off, and ignore it.  This is true, but it
is true in the same way that people are free not to click on email
attachments if they do not want to risk getting a virus.  Security
threats, and the risk of losing the substance of one's being is
probably the biggest security threat of them all, requires active
defense at all levels of the computer system.

There have already been proposals for US law to require all computers
to support "trusted computing", and to enforce its use when connecting
to the internet.  There are other methods of coercion as well.  One
method is to introduce a less harmful variant of control, and then
change the conditions after it is widely established.  Another method
is the exploitation of a monopoly, or conspirations among large
companies to ensure that there is no feasible alternative.  Yet
another method is to spread false information on how the technique
will be used.  All of these techniques and more have already been
used, so these are not speculations, they are facts.

Once you accept the loss of the substance of one's being as a security
threat (I am not saying you need to accept that, but if you do, you
will be able to follow my argument), all the same techniques and
considerations apply to this security threat as to other security
threats.  And it is universally recognized (I hope) that passive
defense is not sufficient in the context of active security threats.


Radical Paradigm Shifts

The "trusted computing" model embodies radical paradigm shifts in how
some people think about ownership and contracts.  Richard Stallman
remarks (http://www.gnu.org/philosophy/can-you-trust.html):

"A previous statement by the palladium developers stated the basic
 premise that whoever developed or collected information should have
 total control of how you use it.  This would represent a revolutionary
 overturn of past ideas of ethics and of the legal system, and create
 an unprecedented system of control. The specific problems of these
 systems are no accident; they result from the basic goal. It is the
 goal we must reject."

The idea that the agent who developed or collected information should
be the sole arbitrator of how the information is used by other agents
is in direct conflict with several social contracts on fair use,
temporal boundaries on copyright protection, obligation to preserve
information (for example audits, or evidence of a crime), and more.

In short, the mediating agent (the implementors of the "trusted
computing" component) is overreaching, in direct conflict to
established laws.  At the same time, for most people, organizations,
businesses and in fact, quite a number of governments as well, the
mediating agent will be unaccountable, because not only it will be
represented by large companies that have assets at their disposal
comparable to some of the smaller nations on the globe, but also,
because the way the technology is implemented, it will be able to
convincingly deny its own involvement (also, nominally, it is the only
party which could have been involved in the matter at all).


On The Imbalance Of Defaults

In the encapsulated, confined example, the confined party risks, by
default, nothing, and the encapsulated party risks, by default, all
the resources that is giving up temporarily, for the whole time of the
contract, without any guarantee for a result.

This is an imbalance of defaults from which a balanced, negotiated
contract is difficult to achieve.  I see no reason why it should be
easier or harder to achieve a balanced, negotiated contract in either
system.  They start from two extremes, and the right solution is
somewhere in the middle.  However, my system does not contain a
comparable mechanism which is imbalanced by default.  Instead, every
agent is in the same situation.  Practically, I think that a balanced
contract is more likely to be the result of equal starting conditions
than from unequal starting positions.


Conservative Choices

In the above sense, my model is really ultra-conservative.  The only
assumption is that it is the owner of the computer who should be in
control over it.  This is in fact, a logical tautology.  I do not make
any further assumptions about what should be imposed.


The Choice Of A GNU Generation

If you read carefully the text by RMS on
http://www.gnu.org/philosophy/can-you-trust.html you will find out
that, although the text focusses on DRM, it really anticipates a much
broader class of problems.  The free software movement depends on the
free software philosophy, it is its heart and soul.  Even if you do
not subscribe to the free software philosophy, you should be able to
agree with the following statement:

Every person on earth should be able to write useful computer programs
and share them with their friends without fees.

For this, several things are required: We must have access to hardware
that obeys our command.  If it doesn't, or even if it only makes it
very hard, we can not write programs for it.  We must have access to
information about how to write useful programs.  For this, we must
learn, and one way to learn is to observe how the programs that our
friends wrote work.  Also, to write programs that are useful in the
real world, we must be able to reverse-engineer other proprietary
programs.  We must be able to publish our own, original work
unencumbered by legal problems like patents.

All of these things must be easy, or otherwise our ability to do our
work is in danger.  In the context of this discussion, my model
supports these operations easily.  The "trusted computing" model puts
them at such a high risk that it threatens the mere survival of free
software.

This is something that is very important to understand.  It is highly
unlikely that the GNU project would accept a technology that threatens
its own survival.  So, if you want to propose a use case for this
technology for a GNU project, you have to demonstrate more than just
that there are people who want to do this.  You would have to
demonstrate that the benefits compensate the risk.  Because the risk
is very serious and very great, the compensating benefit would have to
be equally big.  Because this is a GNU mailing list spawned off a GNU
project with the intent to write an operating system for the GNU
project, I think it is appropriate to point this out.

This does not mean that I am not, personally, interested in hearing
your ideas.  Furthermore, and this is also important to understand, I
do not believe anymore that there is a conflict between the free
software philosophy and the goal of writing a secure and useful
operating system.  The possibility that there might be such a conflict
has been a great concern of mine in the last half year.  However, once
I had resolved two important use cases (suid programs and cut&paste),
I was able to see what parts of the security infrastructure were
actually important to me, and which parts I think are a separable
concern.  From there, it was not difficult to generalize to the above
analysis of ownership and contracts.


Outlook

This then, is my motivation for closely examining how (1) my model can
be technically described, and (2) what its properties are, and (3)
what its justifying design principles are.  This sets the agenda for
upcoming mails, so let me insert a breaking point here.

Thanks,
Marcus





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