wdiff draft-farrell-perpass-attack-00.txt draft-farrell-perpass-attack-01.txt

Network Working Group S. Farrell
Internet-Draft Trinity College Dublin
Intended status: BCP H. Tschofenig
Expires: May 24, June 4, 2014 November 20, December 1, 2013

Pervasive Monitoring is an Attack
draft-farrell-perpass-attack-00.txt
draft-farrell-perpass-attack-01.txt

Abstract

The IETF has consensus that pervasive monitoring is a technical
attack that should be mitigated in the design of IETF protocols,
where possible.

Status of this Memo

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1. It's an Attack

[[Note:

[[Note (to be removed before publication): This draft is written as
if IETF consensus has been established for the text.]]

The technical plenary of IETF 88 [IETF88Plenary] discussed pervasive
monitoring. Such pervasive surveillance requires the monitoring and participants had
party to take actions that are indistinguishable from an attack on
Internet communications. Participants at that meeting therefore
expressed strong agreement that this was an attack and one that should be
mitigated where possible via the design of protocols that make
pervasive monitoring significantly more expensive or infeasible. Such pervasive surveillance requires the
monitoring party to take actions that are indistinguishable from an
attack on Internet communications.
This Best Current Practice (BCP) formally documents that consensus. consensus,
having been through an IETF last call.

For the purposes of this BCP "pervasive monitoring" means very
widespread privacy-invasive gathering of protocol artefacts including
application content, protocol meta-data (such as headers) or keys
used to secure protocols. Other forms of traffic analysis, for
example, timing or measuring packet sizes can also be used for
pervasive monitoring. A fuller problem statement with more examples
and description can be found in [ProblemStatement].

Note that the

The term "attack" is used here in a techincal technical sense that differs
somewhat from the natural common English usage. In particular, common English usage, an
"attack" is an aggressive action perpetrated by an opponent, intended
to enforce the
term, when opponent's will on the attacked party. In the
Internet, the term is used technically, implies nothing about to refer to a behavior that subverts the motivation
intent of a communicator without the bad-actor mounting agreement of the attack, who is still called parties to the
communication. It may change the content of the communication,
record the content of the communication, or through correlation with
other communication events or attempts, reveal information the
communicator did not intend to be revealed. It may also have other
effects that similarly subvert the intent of a bad-actor no
matter what one really thinks about their motivation. We communicator. RFC
4949 contains a more complete definition for the term "attack" as
used here. [RFC4949] Note that we also use the term in the singluar singular
here, even though pervasive monitoring in reality may require a
multi-faceted set of co-ordinated coordinated attacks.

In particular, the term "attack", when used technically, implies
nothing about the motivation of the actor mounting the attack. The
motivation behind pervasive monitoring is not particularly relevant for this
document, but can range from non-targeted nation-
state nation-state surveillance,
to legal but privacy-unfriendly purposes by commercial enterprises,
to illegal purposes by criminals. The same techniques can be used in each case,
regardless of motivation, motivation and we cannot defend against the most
nefarious actors while allowing monitoring by other actors no matter
how benevolent some might consider those. them to be. As technology continues to advance rapidly has
advanced techniques that have been shown to work but were once only accessible
to nation-state actors available in constrained
environments have become accessible to non-nation-state actors,
so mitigating more widely accessible. Mitigating this threat
attack is not only relevant when considering
nation-state bad actors. therefore a protection against wider usage of pervasive
monitoring.

2. And we'll work to Mitigate the Attack

The IETF also have has consensus to, where possible, work to mitigate the
technical parts of the pervasive monitoring attack, in just the same
way as we do with any other protocol vulnerability.

There are various ways in which IETF protocols can be designed in
order to mitigate pervasive monitoring, but those will change over
time as mitigation and attack techniques develop and so are not
described here. This BCP simply records the consensus to design
protocols so as to mitigate the attack, where possible.

Note that more limited-scope monitoring to assist with network
management or that is required in order to operate the network or an
application are not considered pervasive monitoring. There is though
a clear potential for network management mechanisms to be abused as
part of pervasive monitoring, so this tension needs careful
consideration in protocol design: making design. Making networks unmanageable in
order to mitigate pervasive monitoring would not be an acceptable
outcome, but
outcome. But equally, ignoring pervasive monitoring in designing
network management mechanisms would go against the consensus
documented in this BCP. An appropriate balance will likely emerge
over time as real instances of this tension are considered.

It is also important to note that the term "mitigation" is also a
technical term that does not necessarily imply an ability to
completely prevent or thwart an attack. As in common English usage,
this term is used here in the sense of "make less severe, serious, or
painful." [OED] In this case, designing IETF protocols to mitigate
pervasive monitoring will almost certainly not completely prevent
such from happening, but can significantly increase the cost
significantly of such
monitoring or force what was covert monitoring to be more overt, overt or
more likely to be detected (possibly later) via other means. And
even where the IETF has done this work well and that has been fully
deployed, there will still be some privacy-relevant information that
will inevitably be disclosed by protocols.

While RFC 4949 does not contain a definition for the term mitigation,
we prefer it here to the term countermeasure which is defined in RFC
4949 since the latter term is more often understood to mean putting
in place a more fully effective mitigation of an attack.

Finally, we note that the IETF is not equipped to tackle the non-
technical aspects of mitigating pervasive surveillance. We hope that
others Others will
be required to step forward to tackle those. those if pervasive monitoring
is to be fully addressed.

3. Process Note

In the past, architectural statements of this sort, e.g., [RFC1984]
and [RFC2804] have been published as joint products of the IESG and
IAB. However, since those documents were published, the IETF and IAB
have separated their publication "streams" as described in [RFC4844]
and [RFC5741]. This document was initiated by both the IESG and IAB,
but it is being published as an IETF-stream consensus document, having
garnered the consensus of the IETF as approved by the IESG.

4. Security Considerations

This BCP is all about privacy. More information about the
relationship between security and privacy threats can be found in
[RFC6973]. Section 5.1.1 of [RFC6973] specifically addresses
surveillance as a combined security-privacy threat.

5. IANA Considerations

There are none. We hope the RFC editor deletes this section before
publication.

6. Acknowledgements

We would like to thank the participants of the IETF 88 technical
plenary for their feedback. Additionally, we would like to thank all
those who contributed to their suggestions on how to improve Internet
security on various IETF mailing lists, such as the ietf@ietf.org and
the perpass@ietf.org lists. Thanks in particular to the following
for useful comments: suggestions that resulted in changes to this text: Jari
Arkko, Fred Baker, Marc Blanchet, Brian Carpenter, Benoit Claise,
Spencer Dawkins, Adrian Farrel, Russ Housley, Joel Jaeggli, Eliot
Lear, Barry Leiba, Ted Lemon, Erik Nordmark, Pete Resnick, and Peter
StAndre. Additionally, we would like to thank all those who
contributed suggestions on how to improve Internet security and
privacy or who commented on this on various IETF mailing lists, such
as the ietf@ietf.org and the perpass@ietf.org lists.

7. Informative References

[IETF88Plenary]
IETF, "IETF 88 Plenary Meeting Materials", URL:

https://datatracker.ietf.org/meeting/88/materials.html,
Nov 2013.

[ProblemStatement]
Richard Barnes, "Pervasive Monitoring: Problem Statement",
URL: To-Be-Published, Nov 2013.

[OED] Stevenson, Angus, "Oxford Dictionary of English", Oxford
University Press http://www.oxforddictionaries.com/
definition/english/mitigate, 2010.

[RFC1984] IAB, IESG, Carpenter, B., and F. Baker, "IAB and IESG
Statement on Cryptographic Technology and the Internet",
RFC 1984, August 1996.

[RFC2804] IAB and IESG, "IETF Policy on Wiretapping", RFC 2804,
May 2000.

[RFC4844] Daigle, L. and Internet Architecture Board, "The RFC
Series and RFC Editor", RFC 4844, July 2007.

[RFC4949] Shirey, R., "Internet Security Glossary, Version 2",
RFC 4949, August 2007.

[RFC5741] Daigle, L., Kolkman, O., and IAB, "RFC Streams, Headers,
and Boilerplates", RFC 5741, December 2009.

[RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
Morris, J., Hansen, M., and R. Smith, "Privacy
Considerations for Internet Protocols", RFC 6973,
July 2013.

Authors' Addresses

Stephen Farrell
Trinity College Dublin
Dublin, 2
Ireland

Phone: +353-1-896-2354
Email: stephen.farrell@cs.tcd.ie

Hannes Tschofenig
Brussels,
Belgium

Phone:
Email: hannes.tschofenig@gmx.net