Re: [cryptography] Paris Attacks Blamed on Strong Cryptography and Edward Snowden

2015-11-19 Thread Benjamin Kreuter
On Thu, 2015-11-19 at 06:21 +, mtm wrote:
> how did hominids manage prior to crypto?

The same way we managed before writing -- ciphers of various kinds have
been in use for all of recorded history.

-- Ben



signature.asc
Description: This is a digitally signed message part
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] Can we move to a forum, please?

2013-12-24 Thread Benjamin Kreuter
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA512

On Tue, 24 Dec 2013 16:44:24 -0500
Greg g...@kinostudios.com wrote:

 Thoughts?

Can we please *not* do this?  Web forums are horribly annoying places
where we must deal with some other person's conception of what a good
client should look like.

Frankly, after everything that has happened this year, we should be
seeking a more distributed solution, not an even more centralized one
than mailing lists.

- -- Ben



- -- 
Benjamin R Kreuter
KK4FJZ

- --

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell
-BEGIN PGP SIGNATURE-
Version: GnuPG v2.0.14 (GNU/Linux)
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=7Uor
-END PGP SIGNATURE-
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] open letter to Phil Zimmermann and Jon Callas of Silent Circle, re: Silent Mail shutdown

2013-08-17 Thread Benjamin Kreuter
On Sat, 17 Aug 2013 12:30:40 +0300
ianG i...@iang.org wrote:

 This was always known as the weakness of the model.  The operator
 could simply replace the applet that was downloaded in every instance
 with one that had other more nefarious capabilities.  There were
 thoughts and discussions about how to avoid that, but a simple, mass
 market solution was never found to my knowledge [0] which rendered
 the discussions moot.
 
 I don't think the company ever sought to hide that vulnerability.
 
 Also, that vulnerability was rather esoteric as it required quite 
 serious levels of cooperation.  So the bar was still high.

I am not sure I see how serious levels of cooperation would be
required.  Adding a backdoor to the Java applet that forwards a
passphrase or secret key to Hushmail does not sound terribly hard to
do (it sounds like less than 10 lines of code).  It sounds like
something that would almost certainly be done if the company ever
decided to build a lawful interception system.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] skype backdoor confirmation

2013-05-21 Thread Benjamin Kreuter
On Tue, 21 May 2013 14:17:02 +1000
James A. Donald jam...@echeque.com wrote:

 Police install malware by black bagging, and by the same methods as 
 botnets.  Both methods are noticeable.

I do not think the following scenario is terribly far-fetched:

Suppose the police want to target a grad student in a CS department at
a major university.  The police enter the server room, insert some
malware into the student's research group's git repository, and waits
for the student to merge the changes.  The next time the student runs
whatever code she is working on, the malware will be installed; the
malware then installs a keystroke logger, enables the microphone, etc.
The malware can be even more secretive, only activating on a specific
computer (the target's) or perhaps the police could modify the software
on the server to only send the malware to the target.

Now, let's change this somewhat.  Instead of sneaking into a server
room (or presenting the school with a court order), the police
compromise another grad student's computer, and simply commit their
malware to the group's repository (do you think researchers actually
read commit logs, when they have a deadline in a few days?).

Now suppose instead of the police, it is a foreign government trying to
get secret research data.  Maybe instead of targeting one research
group, they just target, say, anyone who keeps Matlab source code in a
git repository.

Now suppose that instead of researchers, it is a political activist
group, and instead of a git repository, it is a shared PDF (let's just
assume that Acrobat has an exploitable vulnerability).  Maybe the
malware will spread by inserting itself into *every* PDF that the user
sends out.

Police and other state-sponsored malware typically target specific
people or groups of people, and usually for surveillance and espionage
purposes.  That is very different from your typical spammer or criminal
botnet.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] [info] The NSA Is Building the Country’s Biggest Spy Center (Watch What You Say)

2012-03-25 Thread Benjamin Kreuter
On Sat, 24 Mar 2012 02:29:30 -0500
Marsh Ray ma...@extendedsubset.com wrote:

 If you're looking for someplace to feel subversive around, this isn't 
 it. Crypto is a mainstream engineering discipline these days, and one 
 greatly needed by modern civilization.

Unfortunately, there is still a great deal of resistance to the notion
that cryptography is something that people should have, at least
cryptography without backdoors.  When last I checked, the Department of
Justice was still pushing communication service providers to include
some sort of back door, so that law enforcement agencies can decrypt
the encrypted communications of suspects in criminal cases.  They
basically think that the Hushmail model is the right one:

http://judiciary.house.gov/hearings/hear_02172011.html

(Apologies for the length; the summary is this:  the FBI is worried
about criminals or terrorists using encryption to hide their
communications from law enforcement and national security agencies, as
well as the lack of CALEA-style systems on the Internet. They as asking
for a law that requires communications service providers to provide
plaintexts if it is possible to do so e.g. Hushmail-style decryption.
The FBI insists that they are not talking about key escrow or key
recovery, and they avoid using the term back door to describe what
they want.)

Even worse, here at UVA we had a graduate student who was denied entry
because he traveled to a cryptography conference (he is here on a
student visa, and is a Chinese citizen). The State Department would not
allow him to come back to school unless he switched fields and stopped
doing computer security work.  He is working on wireless sensor
networks now -- clearly a field that could not possibly have any
national security implications.

The law has definitely improved over what cryptographers faced in the
90s, but the attitudes have not.  The US government still wants a
system where encrypted communications can be arbitrarily decrypted,
they just dress up the argument and avoid using dirty words like key
escrow.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] (off-topic) Bitcoin is a repeated lesson in cryptography applications - was endgame

2012-02-26 Thread Benjamin Kreuter
On Sun, 26 Feb 2012 08:48:05 -0500
d...@geer.org wrote:

 
 Well put, James.  Warren Buffet's arguments are, to my eye,
 aligned with yours.  He argues that gold has no intrinsic
 value, unlike farmland or a company like Coca Cola.  In that
 way, his evaluation is as instrumentalist as is yours, to the
 extent that I understand the both of you.  His discussion of
 gold, per se, is getting some press.  See
 
 2011 shareholder letter
 www.berkshirehathaway.com/letters/2011ltr.pdf
 
 What I would add to your analysis of fiat currency is to agree
 that nails, moonshine liquor, and antibiotics are replacements
 for fiat currency, but I must also note that the modern economy
 is all but totally dependent on large enterprises which, because
 of their largeness alone, simply cannot engage in barter.

It is not just about big business, it is also about maintaining a
functioning government.  There is too much specialization in society
for courts to assign damages in terms of nails, whiskey, cattle, rice,
or whatever else.  How does the government assess a fine in terms of
barter?

Money and government go hand in hand.  Governments need money in order
to manage taxes, fees, fines, and so forth; yet money becomes valuable
because of the legal structure that surrounds it, which is as true for
gold as it is for fiat currency.  Even if you could become completely
self sufficient, to the point of not have to trade with anyone, you
would still need to pay taxes and fees (property taxes, hunting license
fees, etc.), and you will need to make those payments in a manner that
is accepted by the government (i.e. the money issued by the
government).  Barter systems, de facto currencies and so forth only
work on small scales.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] (off-topic) Bitcoin is a repeated lesson in cryptography applications - was endgame

2012-02-26 Thread Benjamin Kreuter
On Sun, 26 Feb 2012 17:57:14 +1000
James A. Donald jam...@echeque.com wrote:

   On 2012-02-26 1:18 AM, Benjamin Kreuter wrote: The demand
   for Bitcoin as a currency is driven by its properties as a
   digital cash system; people still need to get their
   nation's currency at some point
 
 Frau Eisenmenger writes in her 1919 diary:

I am not denying that when governments mismanage currencies, crises and
failures ensue.  This is true of all things governments manage:  when
mistakes are made, large numbers of people wind up suffering.  However,
the failure of some countries' currencies does not mean that people are
going to switch from their nation's currency to Bitcoin.  If the US
Dollar were to fail, Bitcoin would be the last thing on anyone's mind;
we would probably wind up switching to some other government's currency
while we sorted out the mess (Yuan perhaps), or we would just spend our
time killing each other and not worrying too much about money.

Perhaps you just need a short list of reasons why Bitcoin is not
going to replace government issued currencies:

1. No offline transactions, which makes Bitcoin useless for a large
   class of transactions.
2. Fixed upper bound on the number of currency units, which creates
   deflationary trends as economies and populations grow.
3. No governments allow tax payments made using Bitcoin, and there is
   no incentive for them to do so.  Even if everyone used Bitcoin for
   day-to-day trades, they would still have to pay property taxes or
   face arrests, property seizures, etc.  When the government becomes
   too ineffective to enforce its own laws, then Bitcoin might have a
   chance, but only as a way to manage trade in some foreign nations'
   currencies (who will still want to trade with people in the region
   where the government failed), and that is assuming that online
   transactions can even happen in such a situation.

Now, I will grant you this:  there is a very, very, very remote
possibility that every fiat currency in the entire world will fail
simultaneously, and that instead of shooting each other people will
continue to engage in trade (and that the Internet survives the mess).
Even in that case, there will need to be some currency for offline
transactions, and so even then Bitcoin will be relegated to second
place.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] (off-topic) Bitcoin is a repeated lesson in cryptography applications - was endgame

2012-02-26 Thread Benjamin Kreuter
On Sun, 26 Feb 2012 11:00:15 -0500
Bill St. Clair billstcl...@gmail.com wrote:

 On Sun, Feb 26, 2012 at 10:08 AM, Benjamin Kreuter
 brk...@virginia.edu wrote:
  On Sun, 26 Feb 2012 08:48:05 -0500
  d...@geer.org wrote:
 
  Money and government go hand in hand.  Governments need money in
  order to manage taxes, fees, fines, and so forth; yet money becomes
  valuable because of the legal structure that surrounds it, which is
  as true for gold as it is for fiat currency.  Even if you could
  become completely self sufficient, to the point of not have to
  trade with anyone, you would still need to pay taxes and fees
  (property taxes, hunting license fees, etc.), and you will need to
  make those payments in a manner that is accepted by the government
  (i.e. the money issued by the government).  Barter systems, de
  facto currencies and so forth only work on small scales.
 
 You've just made a very good argument for eliminating money, at least
 government issued money. Yes, governments just love to assess taxes,
 fees, and fines. No, I have no need of any of that.

I do not follow your argument -- how does eliminating government issued
money stop governments from collecting taxes and fees?  Governments
whose currencies fail sometimes switch to the currencies issued by
other governments; there are quite a few nations that use US Dollars
instead of issuing their own money.

You may not like the idea of fines or fees, but how would you propose
courts manage disputes between people?  Suppose I fail to maintain my
house, and a piece of it falls off and damages your house -- should you
have to pay for my negligence?  If I raise cattle and you write
software, what should I give you -- a cow perhaps?  Perhaps I should
pay for a repairman to come and fix things -- but what if you do not
like the person I choose?  We have judges and courts to help us resolve
these sorts of disputes, and money is a great way to ease these sorts
of disputes.

You may disagree with the taxes you pay, the fines that are issued, and
so forth -- but would you really want to have a tax collector come and
rate the quality of your work, and then take the products of that work
as a form of tax payment?  Do you want to see people imprisoned,
enslaved, tortured, etc. instead of paying fines?  I also disagree with
the laws in this country, but the solution is not do away with money
or switch to Bitcoin.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] US Appeals Court upholds right not to decrypt a drive

2012-02-24 Thread Benjamin Kreuter
On Sat, 25 Feb 2012 05:30:57 +1000
James A. Donald jam...@echeque.com wrote:

 So:  Don't talk to police about the contents of your drive, or indeed 
 anything of which they might potentially disapprove.

I believe that you meant to say, Don't talk to the police at all,
which should be standard policy for anyone who finds themselves under
arrest.  There is no advantage in talking to the police once you have
been arrested, nothing you say will help in your defense and you are
not going to talk your way out of an arrest.  The odds are stacked
against you during a police interview -- you are talking to people who
have been trained to extract confessions, who are being paid to sit
there interrogating you, and who will pick through what you say to
find incriminating statements.  Stay quiet, speak only to your
attorney, and let your attorney speak on your behalf; you cannot be
penalized for exercising your rights, nor can the fact that you refused
to speak be introduced as evidence against you (at least in the United
States).

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] Homomorphic split-key encryption OR snake oil crypto

2012-02-19 Thread Benjamin Kreuter
On Sun, 19 Feb 2012 17:08:25 +0100
Florian Weimer f...@deneb.enyo.de wrote:

 * Saqib Ali:
 
  Can somebody explain me how this so-called Homomorphic split-key
  encryption works?
 
 Isn't this just a protocal which performs a cryptographic primitive
 using split key material, without actually recombining the keys?
 (Traditional Shamir secret sharing needs a trust party for key
 recombination.)
 
 If yes, you might want to look for RSA Threshold Cryptography and
 similar work.

What is the point of introducing homomorphic encryption here?  When
last I checked, we were still pretty far from practical FHE systems,
and we have not really determined the appropriate security parameters
for the systems we are aware of now.  It is telling that the company in
the link provides few details about their system, except so say that
homomorphic encryption is something they plan to deploy in the future.

Maybe they are talking about oblivious AES from garbled circuits,
although I am not really sure what the advantage of such a thing might
be.

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] trustwave admits issuing corporate mitm certs

2012-02-12 Thread Benjamin Kreuter
On Sun, 12 Feb 2012 05:57:02 -0500
Jeffrey Walton noloa...@gmail.com wrote:

 On Sun, Feb 12, 2012 at 5:43 AM, Krassimir Tzvetanov
 mailli...@krassi.biz wrote:
  While I'm not a lawyer and my opinion is in noway authoritive I do
  not believe there is any violation. They ay be an accessory to a
  potential crime but they themselves did not do the tapping.
 
  Now on the other hand those companies that did the tapping should be
  OK for as long as they are clear with the employees that they cannot
  expect privacy, which usually is the case. Usually this is in the
  paperwork you sing when you start working there in the section
  privacy policy.
 Two questions:
 
 (1) How can a company actively attack a secure channel and tamper with
 communications if there are federal laws prohibiting it? It seems to
 me they can only take the role of passive adversaries and still comply
 with US law,

Plenty of companies install monitoring software on their employees'
workstations and listen to employee phone calls, which is generally
legal:

https://www.privacyrights.org/fs/fs7-work.htm

 (2) Did the other end of the SSL/TLS tunnel also agree to be
 monitored?

Does that matter?

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu
KK4FJZ

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] Gregory Perry's follow-up to the FBI OpenBSD / OCF backdoors thread

2012-01-16 Thread Benjamin Kreuter
On Mon, 16 Jan 2012 18:47:06 +1300
Peter Gutmann pgut...@cs.auckland.ac.nz wrote:

 Harald Hanche-Olsen han...@math.ntnu.no writes:
 
 Maybe it's just me, but I find myself unable to make sense of this
 part:
 
   [...] one mathematical vulnerability in the RSA encryption
  algorithm related to changing the base numbering system of the
  resulting RSA modulus after a block of plaintext had been encrypted
 
 I thought it was positively sensible compared to:
 
   a fellow by the name of Ross Pirasteh, who was either the Prime
 Minister of Finance for the Shah of Iran or actually the Shah of Iran
 himself.  As the story goes, Ross and his family were snuck out of
 Iran rolled up in Persian rugs just prior to or during the 1979
 revolution

Perhaps this leak was actually a chapter from an upcoming spy novel?

-- Ben



-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] Complying with GPL V3 (Tivoization)

2012-01-09 Thread Benjamin Kreuter
On Sun, 8 Jan 2012 22:46:13 -0500
Jeffrey Walton noloa...@gmail.com wrote:

 Hi All,
 
 I was reading on CyanogenMod (a custom ROM project for Android) and
 The story behind the mysterious CyanogenMod update
 (http://lwn.net/Articles/448134/).
 
 Interestingly, it seems some privaye keys were circulated to comply
 with GPL V3 with some nasty side effects (could anything else be
 expected?).

My understanding is that this is not necessary for GPLv3 compliance,
as the license does not require the disclosure of private keys (which
would undermine the entire package signing system used by GNU/Linux
distributions) but instead requires that people be allowed to modify
the software configuration of the system.  That could mean allowing
unsigned software to be installed or allowing a user to add their own
public keys to their system.

 Some interesting points were brought up, including how to
 comply with GPL V3.

Someone else made the same point that I made above:  there is nothing
in the GPLv3 that requires the release of private keys.  It only
requires that users be allowed to install, modify, or remove software.  

 Is anyone aware of papers on integrity/signature schemes or protocols
 tailored for GPL V3? Or does this reduce to (1) allow the
 hardware/firmware to load additional [trusted] public keys; or (2)
 provide the private key for the hardware?

Like I said, you can allow users to add additional trusted keys to the
system, or you can allow users to run unsigned code.  The only
situation that would necessitate publishing a private key would be if
the hardware itself refused to run code that was not signed by a
single, fixed key -- and then GPLv3 compliance will be the least of
your problems.

-- Ben

 Jeff
 ___
 cryptography mailing list
 cryptography@randombit.net
 http://lists.randombit.net/mailman/listinfo/cryptography


-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] really sub-CAs for MitM deep packet inspectors? (Re: Auditable CAs)

2011-12-06 Thread Benjamin Kreuter
On Tue, 6 Dec 2011 12:34:37 +0100
Adam Back a...@cypherspace.org wrote:
 Kids figure this stuff out getting through site restrictions on
 school wifi also.  Some schools try to block popular web games.. eg
 runescape.

Let us not discourage either the children or the schools!  This sounds
like an excellent way for children to pick up some technical skills
and to learn about computer security.  If we must condition our
children to think that censorship is the norm, at least we can also
provide them with some decent education in the process.

-- Ben
 


-- 
Benjamin R Kreuter
UVA Computer Science
brk...@virginia.edu

--

If large numbers of people are interested in freedom of speech, there
will be freedom of speech, even if the law forbids it; if public
opinion is sluggish, inconvenient minorities will be persecuted, even
if laws exist to protect them. - George Orwell


signature.asc
Description: PGP signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography


Re: [cryptography] Math corrections

2011-09-19 Thread Benjamin Kreuter
On 09/18/2011 05:11 PM, Marsh Ray wrote:
 B. If your threat model considers as an adversary government A, then
 you're in good company with governments B through Z. So all the comments
 on won't save you from The Government, while true, are also
 potentially writing off your biggest ally.

Unless, of course, we continue to use the system as it exists today,
where any trusted CA can sign a certificate for anyone.  If a particular
government supports a CA that is cooperative with that government,
then either nobody in the world would be safe, or the system will
fracture and we will not have a global PKI.

 C. At the end of the day, governments need to log into their VPNs and
 check their MS Outlook Web Access email remotely just like everybody
 else. Now consider that this applies to process engineers at power
 plants and chemical facilities too. When you hear US DHS people talking
 about national infrastructure vulnerable to cyber attack they are
 sincerely concerned about this type of exposure.

So the only trustworthy CAs will be the ones that sign certificates for
power companies or other national security related entities?  We need
a system that can be used and trusted (to a reasonable degree) by
everyone, not just big or important organizations.

 At some point, the influence of people on the defense side will outweigh
 those who benefit from the attack side.

I doubt this will happen any time soon.  Consider this official (and
apparently still current) FAQ from the Department of Justice:

http://www.justice.gov/criminal/cybercrime/cryptfaq.htm

Yes, that was issued over a decade ago, but key recovery -- which we
are meant to believe is not the same as key escrow -- remains the DOJ's
goal when it comes to cryptography.  There is also the more recent push
by the Obama administration to create a system that allows law
enforcement agencies to more easily hijack domain names.

 Now that the cat's out of the bag about PKI in general and there's an
 Iranian guy issuing to himself certs for www.*.gov seemingly at will, I
 think the current PKI system will not escape the black hole at this
 point, it crossed the event horizon sometime earlier this year.

I doubt it.  The cat has been out of the bag on how easily email can be
forged for decades now, but how often do you receive digitally signed
email?  The cat has been out of the bag about running out of IPv4
addresses for many years, but IPv6 deployment has been sluggish.
Without a strong incentive, these things will not change, and the PKI is
no different.  I doubt that the current PKI will be gone by the end of
this decade -- criminal MITM attacks are just not in-your-face enough to
generate a public outcry, and governments are not terribly interested in
thwarting their own law enforcement agencies.

-- Ben



signature.asc
Description: OpenPGP digital signature
___
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography