Subject: Re: [Raven] Nevermore ...

From: "chefren" <[email-masked]>
Date: Mon, 1 Nov 1999 22:36:38 +0100

On 29 Oct 99, at 18:01, [email-masked] wrote:

>    We are contemplating a practical quagmire and no less than the tapping
>    of every IP protocol not just VoIP.  It undermines the good work of the
>    IETF.

I don't see why. If the users crypt their data end to end a 
communication provider cannot do more than providing the 
raw data.

BUT: That's still interesting for law enforcement. There 
are fingerprints in it and all kind of other information.

..

> Let's pray there is no "Phoenix" list.

I don't think there will be another chance for 
standardization. After this everywhere in the world 
different standards will pop up and the costs for us all, 
will be maximized. with that.

I'm only putting so much effort in this because I know they 
are busy here and wish our systems in The Netherlands to be 
compatible with US and other countries. If only the Dutch 
tapbox would be open-source it would be nothing less than a 
vulnerability. Only a wide accepted standard is studied 
enough to be able to say it's secure to some extend.

Unaudited taps for law-enforcement are unthinkable on the 
long run in The Netherlands. Of course they are busy with 
tcpdump now but that will definitely end when better 
technology pops up.

  They started tapping telephones 25-30 years ago in a
  room filled with cushioning because the speaker could
  induce voice of law enforcers on the tapped line and now
  they have all kind of administrative and technical
  requirements. The newest GSM and ISDN taps even have
  digital authentication and everyone is happy with it
  since privacy and responsability are in check as good as
  we can think of.

+++chefren

=Large signature follows=

I think we need a simple architecture for a point
to point tap interface that has strong provisions
against misuse.

On one side the communication provider who only
starts tapping a specific customer or IP number
with proper warrants.

On the other side the approved tapping room.
Everything should be organized by the central
"tapping office". This office should provide
keys for strong encryption to both communication
provider and tapping room.

Law and technology should both provide as
much checks and balances as we can come up
with. Law can provide good procedures,
technology can provide technical means to
check them or force them.    

=Large signature ended, please comment me
off-line to make it better=

_______________________________________________
raven mailing list
[email-masked]
http://www.ietf.org/mailman/listinfo/raven

---

From: "Richard Payne" <[email-masked]>
Date: Tue, 2 Nov 1999 14:40:26 -0500

ch*fr*n wrote:

> I think the crypto-believers monopolize this discussion
> with something thats completely irrelevant. The problem is
> that almost all governments in this world require taps.

It is true that almost all governments require taps of "plain old telephone
service" (POTS), but whether (say) the U.S. currently has laws in place to
demand it for the Internet is one of the topics we're discussing. No-one has
(to my knowledge) proved this yet to the list.

Crypto is relevant because, as end-to-end strong crypto becomes more
available, taps become less useful. As systems like Zero-Knowledge Systems'
Freedom become available, then traffic analysis also becomes harder. The
writing has been on the wall for at least five years - the world is likely
going to become less and less tap-friendly. You may not like it, Louis Freeh
may not like it, but e-commerce makes it really hard to go back in time.

ch*fr*n also wrote:

> I tend to kind of hate crypto discussions with believers,
> as others stated they cannot quantify how strong the
> encryption is but they =talk= as if strong encryption is
> 100% "safe". Reality in crimefighting: Nothing proves to be
> 100% safe in all cases. Law enforcement may for example get

Now, I don't think anyone here actually believes any security measure is
100% effective. What's being talked about is degrees of security. "Given
enough eyeballs, all bugs are shallow" has a certain amount of truth to it.
It comes down to which you think is more debuggable: protocols or politics.

And then ch*fr*n wrote:

> You haven't even started at your own proposition: If
> communication cannot be tapped governments will defacto
> allow organized crime.

Now, I asked before why this line of reasoning doesn't lead to the
conclusion that all face-to-face communication should also be
tapped/recorded/wired, and the response was something like "because it
hasn't been in the past". It's probably worth explaining in more detail why
talking in the same room isn't threatening to the basis of society but
sending a secure e-mail is. I don't see how you can avoid a slippery-slope
argument to 100% surveillance.

Richard Payne

---

From: "Brett Wooldridge" <[email-masked]>
Date: Tue, 2 Nov 1999 15:42:39 -0600

From the charter originally posted:

Should the IETF as an international standards organization shape its 
protocols to support country-specific legal requirements?

   Why should it?  If country X forbids encryption (they exist), should
   the IETF not require encryption as part of a protocol, even though
   deployment would be illegal in that country?

   Clearly the answer is "No".  They have already done so, as acknowledged
   in the group charter:

      When IPv6 was under development, the IETF decided to mandate an
      encryption capability for all devices that claim to adhere to those
      standards.  This was done in spite of the fact that, at the time the 
      decision was made, devices meeting the IPv6 standard could not then
      be exported from the U.S. nor could they be used in some countries.

If the companies who employ the IETF participants and deploy the 
 IETF's technology feel that having wiretap capability is a business 
 necessity due to the regulatory requirements in the countries where 
 they want to sell their products, would that make a difference to the 
 IETF position on this subject?

   It would be disappointing if the IETF, the body driving internet standards,
   based decisions market forces.  The IETF should operate under the
   assumption that the internet cannot and will not be confined by national
   borders.  Countries who choose not to "integrate" with the rest of the
   internet (as defined by IETF), will quickly become Third World countries
   in the coming decades.  e-Commerce is about to hit business in a big
   way.  Any country not "on the net" because of political fears of an
   information empowered populace, will bow to the pressure and lift such
   outdated regulations.

What is the appropriateness or feasibility of standardizing mechanisms 
to conform to requirements that may change several times over the life
cycle of equipment built to conform to those standards?

   Why bother?  Define a spec., it to be implemented and adopted as the
   defacto standard.  Changing the spec. after equipment and software is
   in place would cost literally billions of dollars.  No government would
   ever require such a move.

If these functions must be done, is it better for the IETF to do them 
so that we can ensure they are done in the most secure way and, where 
 permitted by the regulations, to ensure a reliable audit capability?

   Again, why bother?  How about take a cue from IPv6 and define a
   standard that is simple illegal (unimplementable) in some countries?
   What is China, for example, going to do?  Disconnect from the
   rest of the planet because they want to evesdrop on their citizens
   and IPv6 won't let them do that?  I don't think so.

   Trust me when I say that the work of the IETF can literally change
   goverments and societies; lifting personal freedom and privacy to
   new levels.  Certainly governments will resist the change -- for
   example, the loss of their ability to conduct wiretaps -- but change
   they will because their economic destiny lays there.
 
What would the image of the IETF be if we were to refuse to standardize 
any technology that supported wiretapping?  In the Internet community? 
 In the business community?  To the national regulatory authorities?

   The IETF would be carried through the streets to a ticker-tape parade
   by the Internet community.

   The business community would stand solidly behind the IETF, as they
   have been backers of strong-encryption exports.  A secure Internet is
   good for business.

   The national regulatory authorities would deride the IETF as an out-of-
   control body, then go back to ensuring that the bread and circuses
   continue making their rounds to the people.

Brett

---

From: Vernon Schryver <[email-masked]>
Date: Wed, 3 Nov 1999 16:08:23 -0700 (MST)

> From: "Brett Wooldridge" <[email-masked]>

> > A 1000 Gbit/sec router that can do "NAT/PAT-style source-IP rewriting"
> > for everything that passes sounds like a far more interesting box than
> > the current 1000 Gbit/sec routers.
>
> Really?  Current routers are capable of doing this already.  The Cisco 7500
> supports NAT, and is capable of 1M pps (OC-12 speeds).  The Cisco 12000GSR
> is capable of OC-48 speeds, and is technically capable of, though doesn't currently
> support, NAT for every packet.  The only reason NAT isn't on the 12000GSR is
> that its positioned as a backbone switch, not something a company would use for
> concentrating IPs.  Still, the fact exist that routers today ARE capable of Gbit
> speeds along with packet rewriting.

It's not the rewriting, but knowing the values that should replace the
old addresses and port numbers.
(Please note that while I don't have the qualifications in routing
experience of a few other authors here, I've written code related to
routing that is widely used on the net, and I've been paid to write other
code for use in commercial 1000 Gbit/sec routers.)

> > Never mind the amount of state required to remember which addresses
> > and port numbers have been rewritten into which new values, nor how it
> > knows when to retire the state.  <snip>  Just think about the address
> > space problems.  From which and to which address and port spaces
> > do you map, and how do you keep it all straight?
>
> While seemingly overwhelming, all of these problems must be overcome
> even in any mid-scale router than supports NAT.  Yes, every connection gets
> assigned a new (singular) IP and port, etc.  Mapping entries take up a
> suprisingly small space -- the 7500 does it all in 128M of RAM, and the
> 12000 Gbit switch comes with 128M expandable to 256M.  Even if it took 1G
> of RAM, we're talking about a $150,000+ switch here.  Cisco even supports IP
> pools for NAT, so exhusting ports is not even an issue.

It's not the size of the table, but knowing what to put into the table,
and accessing and maintaining the table at speed.  Maintaining your mapping
table would be at least as big a problem as maintaining a routing table,
and that is a major problem in today's routers.  Do you have any idea what
it takes to do the BGP and OSPF processing on a realistic set of routes
(as defined by prospective customers for 1000 Gbit/sec routers) and just
keep up with normal updates?

Just how do you define your mapping?   Does each router pick a random
IP address and port number?

> > How do you ensure that all routers through which a TCP/IP connection might
> > be routed at one time or another do consitent mappings, in a way that only
> > the good guy routers and none of the bad guy spies can predict?
>
> The idea outlined ensures perfect forward secrecy.  Each router, even one
> inserted in the chain by the NSA, sees the source of the packet as the
> machine before it, denying an audit trail.  Traffic entering a router is decrypted
> and re-encrypted to ensure that the "gozeintas and gozeoutas" never
> match.  You must have missed that.  That along with out-of-order delivery (I know, it occurs already) foils all by the most
> hardcore-accessible-to-maybe-
> three-governments traffic analysis (even then I'm not convinced it's vulnerable).

Never mind that when out-of-order deliver occurs, it is expensive in its
effects.  Please read about TCP fast retransmission and TCP slow-start
for clues why.  There are now even RFC's on those subjects.

Stop and think about the word "address".  Does it make any sense to have
an address that is not constant and well known to the world?  Why do you
think that we call those 64 bits in the IP header "addresses"?  If they
did not need semantics analogous to real world addresses, including
relative permanence and large scale uniqueness, they would be called
foozleballs instead of addresses.  The IP addresses tells a router where
to send the packet next or where to return the headers in an ICMP message.
If the IP addresses have been translated into randomness, they cannot
serve that purpose.  Thus, if you do translate IP addresses, you must
do it by a clear scheme that the routers and bad guys can figure out.

When you send a TCP/IP SYN to an HTTP server, don't you want the server
to respond with a SYN-ACK?  How can the HTTP server do that unless there
is a "address" on your packet that tells the HTTP server where to send
bits to you?  Moreover, that "address" must tell every router in the path
from the HTTP server back to your machine what to do with your bits.  That
"address" must uniquely identify your computer to the HTTP server and
every router in between.  If any of those routers translate that address,
the translated value must be to an equally globally unique value (modulo
the perspective of that router) that uniquely identifies your computer.
If not, then some other computer will get your bits.  Now consider that
what the good-guy routers can do, as a group trace the path between you
and the HTTP server, so can the spooky spies.

Just because NAT/PAT works just fine between the Internet and a large
number of leaf networks all of which use the same RFC 1918 address space
does not imply that it makes sense elsehwere.
Why do so many of the people running tiny, home networks with NAT/PAT
imagine that what they are doing is the same as what happens in the
default-free part of the net?  This is not the only case where people
think that because NAT is great for their home PC's and because it can be
used to connect large, private corporate networks to the Internet, that
it therefore can do everything including slice bread.

> > How do you do routing in such a network where every address is purely
> > local?  Other than pure source routing, I don't see how, and that would
> > somewhat defeat the purpose of hiding things from snoops.
>
> I'm not sure I catch your drift.  Other than to say, one can use NAT even
> between segments of an internal network.  Are you concerned that you
> can't effectively "route", if all packets appear to come from the same
> IP?

No, that is not the problem, allthough NAT as you'd use it necessarily
involves rewriting both the source and the desitination addresses, or else
there would be no increased privacy.  The problem is what you mean by an
address, and technical problems such as getting ACKs.  When a router
receives a packet with a rewritten destination address, to where does it
forward it?  An IP address, whether translated or not, must be permanent
in the sense of lasting longer than any TCP connection involving it
(including related TCP connections such as FTP data) and global in the
sense of telling every host and router that ever sees it a next hop in
the path.

If all routers and hosts know how to deal with every IP address they see,
then your evil spies can do the same, and so trace every IP address,
whether translated or not, both back to you and forward to your intended
destination.

>      Routing from A to B is based off the destination IP, not the source,
> otherwise NAT wouldn't work at all.  If you are speaking of a network
> in which there is no router (thus no NAT), you're right, no guarantee of
> privacy, other than simple encryption.  Oh well.  But the 'I' in IETF stands
> for Internet, not Intranet.

The "E" in IETF standards for engineering, not political nonsense.
Technical content free or worse political posturing about the desirability
of privacy is just as irrelevant here as technical content free political
posturing about the desirability of fascist (see an English dictionary)
police monitoring eveything in imaginary "tapping rooms."

> > Nver mind that such mapping would do no more than slightly inconvenience
> > the naughty spies.  It would be a lot easier for a snoop to compare the
> > gozeintas and gozeoutas and figure out how interesting streams are being
> > routed in real time than it would be for the router to figure out and
> > maintain the mapping.
>
> If I didn't address the concerns above, let me know.

My "concerns"--sheesh.  Please find someone to explain what a router is
and the nature of IP addresses.

>                                                       In any case, my major
> point was, IETF should to everything technically within it's power to ensure
> security.. ...

The IETF has long since decided to take that position.

>                 ...    All that's required for that is encryption and not
> tagging packets with serial numbers.  IPv6 has the former, what some of
> us here are lobbying for is the latter.

It makes as much sense to talk about "not tagging packets with serial
numbers," as to talk about having the post office deliver physical mail
without addresses.

Privacy is too important to leave to such fuzzy thinking...no, that
characterization is too gentle.

Vernon Schryver    [email-masked]