[HN Gopher] The cryptography behind electronic passports
___________________________________________________________________
The cryptography behind electronic passports
Author : tatersolid
Score : 108 points
Date : 2025-10-31 11:33 UTC (11 hours ago)
(HTM) web link (blog.trailofbits.com)
(TXT) w3m dump (blog.trailofbits.com)
| mothballed wrote:
| The amount of human effort, labor, and heartache put into
| squabbling over where someone was born or was naturalized is
| absolutely mind blowing.
| axus wrote:
| The native Americans tolerated immigration, and we all know
| what happened to them.
|
| On the topic of the article, every hotel outside the US I've
| used has asked for my passport; I didn't know that a copy of
| the details exposed weaknesses on the electronic side.
| xhkkffbf wrote:
| Tolerated? Some welcomed it and some actively fought several
| wars against it and lost. Many tribes conducted some kind of
| economic transaction that traded land for something else.
| mistrial9 wrote:
| Various California native people practiced slavery and
| indentured servitude _on each other_ before the arrival of
| Spanish Catholics. The Mayan people went further than that.
| iso1631 wrote:
| Still do. Slavery is perfectly legal in modern day USA,
| it's enshrined in the constitution
|
| > Neither slavery nor involuntary servitude, except as a
| punishment for crime whereof the party shall have been
| duly convicted, shall exist within the United States, or
| any place subject to their jurisdiction.
|
| Which is functionally the same as
|
| > slavery or involuntary servitude, as a punishment for
| crime whereof the party shall have been duly convicted,
| shall exist within the United States, or any place
| subject to their jurisdiction.
| tatersolid wrote:
| Actually the two are very much not the same logically.
| The real text quoted first allows for servitude in
| limited circumstances. Your second modified version
| _requires_ it.
| Phemist wrote:
| Yes, as this blog post doesn't mention it, the "password key"
| is specifically derived from your Date of Birth, the
| document's Date of Expiry and the Document Number. For the
| specimen document in the blog post these values are
| respectively 740812 (YYMMDD), 120415 (YYMMDD) and L898902C3.
| They are contained in both the MRZ and the VIZ (Visual
| Inspection Zone).
|
| Considering the Date of Birth and Date of Expiry are
| necessarily limited in entropy, one should take care in
| protecting their Document Number as it is the greatest source
| of entropy for the derived "password key".
| iso1631 wrote:
| > Every hotel outside the US I've used has asked for my
| passport
|
| Every hotel in the US and any other country has asked for my
| passport (and credit card), but I'm not American.
|
| The textual information on the page of my passport is
| basically public knowledge, like a phone number or an
| american social security number. It's rare that a hotel takes
| the passport out of sight (and potentially scan the chip),
| but a photocopy is fairly frequent.
| wat10000 wrote:
| The USA welcomed immigration and we all know what happened to
| them.
| ghaff wrote:
| I very much doubt if every hotel I've stayed in outside the
| US has asked for my passport but certainly many/most have.
| Never really paid much mind.
|
| As a US resident, I have often been asked for a drivers
| license in the US and it was actually an issue at one point
| when I had lost it though I was able to work around with some
| difficulty. I suspect the details were some combination of
| local/state/and hotel policy.
| stackskipton wrote:
| Most hotels I've stayed at ask for ID. If you are foreign,
| they want a passport only.
|
| I have had issues with US hotels accept US passports and
| fought with one over it.
| ghaff wrote:
| I expect that quite a few hotel clerks in the US are just
| not familiar with anything other than a driver's license
| as government ID (or think a driver's license is the only
| acceptable ID). I'm pretty sure that I would have an
| issue with a global entry card at some point if I were to
| routinely use it outside of TSA (as I do after my
| driver's license issue) even though it's perfectly valid
| US government ID.
|
| Generally speaking, hotels in the US do seem to want
| government ID. Don't really know the requirement in
| general. This was a fairly low-rent chain that I was only
| using because last minute. I expect if it had been one of
| my major loyalty chains, a manager would have fixed
| things pretty quickly.
|
| ADDED: Normally I travel with a passport as well but, as
| I say, this was a last moment short trip so I didn't
| throw in all my travel pouches.
| hylaride wrote:
| Passports are much more common in some countries, and for
| most of the others where it's not you were probably obviously
| a foreigner based on your appearance, accent, or the fact you
| were likely in a tourist area.
|
| Many countries also have mandatory registration of foreign
| visitors that hotels do automatically so they know the drill.
| alphazard wrote:
| A democracy cannot function if the electorate is not well
| defined. They are vulnerable to Sybil attacks, same as the
| distributed ledgers and hash tables.
| Danjoe4 wrote:
| Go to South Sudan and tell me if you still feel the same way.
| xhkkffbf wrote:
| If you want to have "safety net" social programs, it can't be
| avoided. At least until there's only one government.
| iso1631 wrote:
| In the UK I don't need a passport to travel or move home, yet
| social programs and taxes vary not just between the
| constituent nations but also between smaller government
| areas. It's often decried as a "postcode lottery".
|
| I'm certain that it varies even more between American states.
| Presumably the social "safety net" assistance in California
| is different to that in Montana. In Alaska people get free
| money.
|
| Entitlement tends to be based on where you live
| z2 wrote:
| It is one of the core concepts of sovereignty--defining a
| territory and then deciding who or what gets to be inside.
| Along with a government with a monopoly on violence used
| inwards, and some foreign relations directed outwards, you have
| the recipe for a modern country.
| toomuchtodo wrote:
| Also, access to nation state provided benefits, which is
| limited because resources are (currently) limited.
| drsim wrote:
| It is a shame you are being downvoted, as it is an admirable
| ideology: why should someone be (dis)advantaged by the accident
| of where they were born.
|
| In reality though, 8 billion people hold a wide spectrum of
| beliefs. I would not want to live in a society with low
| taxation and low welfare for example. How can I live side-by-
| side with those that do? Of course, we all have limited choice
| to move if our society does not match our beliefs.
| lazide wrote:
| It also essentially defines who is asserting ownership over
| someone (from the sense of 'who gets the body if they die?'
| to 'who is going to go to war with us if we do something they
| _really_ don't like to this person'). Not to mention if
| someone gets hurt and ends up in a coma or something, who is
| responsible for the bills?
|
| Which may seem like hypothetical questions to the young or
| the inexperienced, but are very real concerns hidden behind a
| veil of generally maintained civility in most of modern
| society.
| morshu9001 wrote:
| Plenty of the 8B people will take you up on that high
| taxation and welfare offer
| 15155 wrote:
| How do you offer entitlements and quality healthcare to the
| entire population of the world without money?
|
| Who should be allowed to participate in the decision-making
| process that allocates these finite resources?
| ceejayoz wrote:
| Who said anything about "without money"?
| 15155 wrote:
| Money is finite - where is this money coming from?
|
| Vacuuming the (imaginary - we're using feelings here, let's
| not split hairs on things like 'markets') accounts of every
| billionaire and redistributing these funds evenly amounts
| to singular thousands of dollars to just _citizens_.
|
| The overwhelming majority of actual taxpaying citizens
| don't pay enough tax to cover their per-capita share of
| government spending, is there some factual evidence to
| suggest that unlimited economic migrants would? (or could?)
| ceejayoz wrote:
| Money is finite. So are basic survival needs.
|
| We certainly can't give everyone a Bezos yacht. But we
| can probably have a little less famine, as a treat.
| gruez wrote:
| >But we can probably have a little less famine, as a
| treat.
|
| Surely it's cheaper to do that via foreign aid in
| whatever country that's experiencing famine, where the
| cost of living is lower?
| ceejayoz wrote:
| Yes, we should absolutely undo the USAID cuts.
| 15155 wrote:
| > Money is finite. So are basic survival needs.
|
| Yes, and the United States cannot shoulder the burden of
| the entirety of the world's economic migrants.
|
| Where is this magical, commensurate influx of licensed
| doctors coming from to deal with the influx of unlimited
| economic migrants (who can't cover their own tax
| expenses?)
|
| We're not talking about yachts: we're talking about
| healthcare and food. Take all the yachts away, force
| Bezos to liquidate everything (and every other
| billionaire): neither the income nor the fixed assets are
| enough to cover healthcare for the population we _already
| have_ , much less a gargantuan, unproductive group of new
| arrivals.
| ceejayoz wrote:
| But no one proposed bringing everyone to the US and
| leaving the rest of the world as a depopulated national
| park?
| gruez wrote:
| >The overwhelming majority of actual taxpaying citizens
| don't pay enough tax to cover their per-capita share of
| government spending, is there some factual evidence to
| suggest that unlimited economic migrants would? (or
| could?)
|
| Exactly. Evidence actually points in the opposite
| direction:
|
| https://www.economist.com/sites/default/files/images/prin
| t-e...
|
| https://www.economist.com/content-
| assets/images/20250315_FNC...
| 15155 wrote:
| Basic math would show you that the vast majority of
| _citizens_ cannot cover the taxable Federal spend: $6.4T
| /340M persons = $18823/individual. ~$20k in taxes are
| paid at ~$100k in income. The US taxation regime is
| highly progressive, obviously the vast majority of the
| country is not earning $100k annually.
|
| > Evidence actually points in the opposite direction:
|
| I was speaking about the United States: can you find a
| study that somehow documents illegal immigrant (by
| definition: undocumented) persons' productivity?
|
| Folks brought over on _legal_ immigration visas likely
| _do_ make more money (and contribute more) than the
| average American: that 's why we have these programs for
| 'exceptional' individuals. Nobody is going through the
| effort (nor can they afford the costs) of obtaining
| lawful visas for construction labor or meat processing
| staff.
| gruez wrote:
| Read my comment more carefully. "Exactly" implies I agree
| with you, and so do the charts, which shows that
| immigrants are either a net drain on public finances, or
| only a subset are net contributors (and therefore implies
| some sort of screening is needed).
| wat10000 wrote:
| You might be underestimating the wealth of modern
| billionaires. According to Forbes, the net worth of the
| 50 wealthiest people in the US totals about $3.9
| trillion. There are something like 320 million US
| citizens at the moment, so that's around $12,000 each.
| That's just the top 50. All US billionaires would be
| about $8 trillion, or $25,000 per citizen.
|
| I agree with your overall point, seizing all the
| billionaires' wealth and redistributing it doesn't solve
| money woes (there are other reasons to do it), but they
| amount they do have is getting strikingly high.
|
| In any case, money is accounting, not ability. The
| important question is: do we have the resources and
| skilled people needed for it? If not, then all the money
| in the world won't make it work. If so, then it can be
| done if people want it badly enough.
| paddleon wrote:
| who said anything about finite?
| wat10000 wrote:
| The downvotes on this comment are wild. Like, you didn't even
| say we should definitely enact open borders right now. You just
| lamented how things are. And it is absolutely lamentable. All
| the responses are basically saying "but we need it!" Which
| isn't even addressing what you're saying. Plenty of necessary
| things are lamentable.
| foofoo12 wrote:
| I was going to respond, but when I looked in my bag of
| trollfeed I saw it contained fuck all.
| blackcatsec wrote:
| The comments rebuking you appear to forget that by definition
| GDP and wealth are derived from the population. Wealth for
| social programs is not a finite resource as the general
| consensus is that over one's lifetime more wealth is created by
| one's work effort than is needed to sustain the individual.
| Capitalism by definition extracts this extra wealth for the
| private interests of a few. But there's no particular reason
| that this extra wealth can't be used to assist those that may
| not even meet the necessity of output of sustaining themselves.
|
| This is a difficult concept for people to understand because
| they look at their paychecks and go "I'm not deriving so much
| wealth!" well yeah. A huge, large chunk of your wealth is being
| extracted for capitalism. And in manners that will be very
| difficult for you to understand.
|
| I'll try to explain it, though, for the audience that peruses
| these forums. You're a software developer.
|
| You work for a public B2B software company. Your wealth is
| being extracted to: Pay for those company pizza parties, pay
| for the office you work in, pay in to the healthcare system
| that "your company is paying for" that isn't directly part of
| the premium you see on open enrollment, paying for the company
| holiday parties, paying into everyone's various insurance plans
| to reduce the out-of-pocket costs for everyone in those
| insurance plans (outside of your company, of course), paying
| for the CEO's multi-million dollar paycheck, paying for the
| bonuses of all of the management, paying for shareholder value
| and dividends, paying for the taxes your company pays, paying
| for the taxes you pay.
|
| If your existence at your job didn't pay for those things, most
| companies will tend to lay you off.
|
| And this goes for pretty much the vast majority of workers in
| the vast majority of jobs.
|
| So saying that more immigrants somehow puts a strain on the
| system is just by definition incorrect, even if a percentage of
| those immigrants don't generate the same level of value you do
| as an individual. Do you think every person in your
| organization generates the same relative value? Of course not.
| In most businesses in America, does the janitor generate the
| same wealth as the CEO?
|
| To be fair, there is a snarky comment to be made there about
| CEOs--but the objective reality is probably not. But the
| janitor is still generating some wealth by ensuring a safe,
| healthy, and comfortable workplace for the employees. Does that
| mean the janitor is not entitled to income? to healthcare? to
| benefits? to company holiday parties? to company pizza parties?
|
| Just convert this into a much larger scale of the entirety of a
| country's population--and well, the answer is that most
| populations have enough free money floating around _somewhere_
| to provide essential services to everyone: education, food,
| safety and security, health, and likely even housing,
| electricity, and pretty much any other public service we could
| provide.
|
| And this scales as a population grows.
| blackcatsec wrote:
| To build on this: One might ask, why don't countries with
| larger populations directly derive more wealth (particular by
| measurement of GDP) than smaller populations naturally?
|
| There are a lot of reasons for this, but the short answer is
| that health, education, and enough individual wealth to
| explore figuring out ways to generate new revenue streams is
| important. Authoritarian countries are by nature not able to
| do this due to limits of their authoritarian nature, not
| necessarily limits of their population numbers.
|
| It's all intertwined :)
| IncreasePosts wrote:
| Do you treat your immediate family better than an absolute
| stranger?
|
| If so, why? Aren't they all just people?
| morshu9001 wrote:
| It's because generations/families are a thing. Even the
| countries taking the most immigrants like USA aren't expecting
| an immediate benefit, they're thinking 1-2 gens later.
| SJk7TAy wrote:
| I have a very practical question with big political implications:
| Can electronic passports be used to make large-scale elections
| without government involvement?
|
| I am thinking of authoritarian countries that issue modern
| e-passports but do not allow free elections. Can activists
| organize an election for all citizens of that country in some
| online form, asking the voters to scan their passports using
| their phones, so that
|
| - only legitimate citizens (who have passports) can vote - votes
| remain anonymous - everybody can vote only once - the whole
| election can be audited
| iso1631 wrote:
| > authoritarian countries that issue modern e-passports but do
| not allow free elections
|
| Those tend to not issue passports (of any kind) to many
| citizens.
|
| Then there's access. In America for example only half the
| adults in the country even have a passport, and I suspect that
| skews quite heavily towards one demographic. Do you think that
| India, Nigeria, or Russia have more equitable access?
|
| And even if they did, what stops the state issuing extra fake
| passports to citizens they want to vote.
|
| of course then there's key elements of a free election, freedom
| of access to the ballot paper, freedom to campaign the same as
| others, freedom from imprisonment because you are running
| against the incumbent leader, having each vote being worth the
| same. Many countries prevent people in jail from voting, or
| even people who used to be in jail. Many countries give more
| power to one constituency than another, almost all have some
| level of unequal access to campaigning.
|
| It's not a "Free election" or "no election".
|
| The actual casting of the vote is only part of the story.
| alphazard wrote:
| Yes, as long as the passports implement a signing scheme, and
| the set of valid public keys (the electorate) can be agreed
| upon. If you can sign arbitrary data, then you can sign other
| public keys, including whatever the voting system requires.
|
| Vitalik has a great blog post about blockchain voting.
|
| https://vitalik.eth.limo/general/2021/05/25/voting2.html
|
| You probably wouldn't want to use the cryptography on the
| passports themselves to implement the voting system. You
| probably want to use one of the general purpose zkSTARKs or
| multi-party-computation systems.
| morshu9001 wrote:
| Can it be anonymous though? Ie you as a citizen can check
| that the outcome didn't count illegitimate votes, and that it
| included your vote, but can't tell who voted each way or at
| all.
| gruez wrote:
| hence why
|
| >You probably wouldn't want to use the cryptography on the
| passports themselves to implement the voting system. You
| probably want to use one of the general purpose zkSTARKs or
| multi-party-computation systems.
| morshu9001 wrote:
| Even if you're using a separate key for voting, the
| passport key had to sign it. How do you prove legitimacy
| of the voting key without exposing the passport key? It's
| not like in blockchain where your anonymity normally
| comes from people just not knowing which irl person owns
| a pubkey. (Though I know Monero etc use homomorphic enc
| for anon payments)
|
| I'm also assuming here that the govt is signing all the
| passport keys, cause idk how else that would work.
| alphazard wrote:
| Yes, it is possible to anonymously aggregate votes from a
| set of public keys, and ensure that no key has voted twice.
| It's also possible to ensure that one's own vote was
| included in the total.
|
| The fact that this is even possible is deeply un-intuitive
| as it requires some of the most sophisticated cryptography.
| That's probably the greatest barrier to adoption. When
| people think of electronic voting, they think about
| trusting a company to make machines that operate on
| plaintext, and require humans to guard access to the
| machines. They aren't thinking about systems that are
| provably correct, where it is more likely for an asteroid
| to wipe out the country conducting the election than for
| the election results to be incorrect.
|
| For the details and tradeoffs, I highly recommend Vitalik's
| blog.
| miki123211 wrote:
| The problem is ensuring that the set of allowed public
| keys you have is actually the set of allowed public keys
| you want.
|
| As others in the thread have said, there's nothing
| stopping the government from manufacturing millions of
| fake passport (or even just generating millions of fake
| passport keys) and using them to rig the election.
| morshu9001 wrote:
| For the purposes of this, I was assuming 1:1 passport to
| citizen and just wondering if that can be made anonymous.
| The real idea with an untrusted passport authority
| doesn't work ofc.
| stuffn wrote:
| This seems like navel gazing. Under OP's constraints it
| wouldn't matter what the tally is. The authoritarian won't
| cede power because they lost by a cryptographically secure
| election. They'll either
|
| A. Force the cryptography to be weak to provide plausible
| deniability
|
| B. Issue more passports for "citizens" that "voted" for them
|
| C. Refuse the count and just keep power
|
| Leaders don't cede power because their citizens are angry.
| Especially not in authoritarian countries.
| morshu9001 wrote:
| The authoritarian govt controls who gets passports and can
| create fake people if it wants.
| embedding-shape wrote:
| I think once an authoritarian government is holding
| elections, regardless digital, analog or anything else, they
| can manipulate the results, there is no 100% foolproof way of
| holding honest elections when the top authority might not be
| honest.
| morshu9001 wrote:
| See also: e2ee on Facebook Messenger
| j16sdiz wrote:
| > authoritarian countries that issue modern e-passports but do
| not allow free elections
|
| You are trying to solve a political problem with a
| technological solution.
|
| 1. Many authoritarian countries don't allow freedom of travel
| (i.e. it is not easy to get a passport)
|
| 2. If they don't care free election, what's stopping them
| issuing more passport just for voting?
|
| 3. What's stopping them confiscating or revoking your passport?
| Muromec wrote:
| >Can activists organize an election for all citizens of that
| country in some online form, asking the voters to scan their
| passports using their phones, so that
|
| By the point said activists reach organizational capacity to do
| so, they have already won and can hold the vote basically with
| scanning a qr code with a simple app.
|
| >only legitimate citizens (who have passports) can vote
|
| this makes no sense as a requirement in a situation you
| described.
| darkamaul wrote:
| I never realized how much complexity goes into a passport, the
| cryptography, authentication layers, and others are mind blowing.
|
| It's impressive that something so small carries so many trust
| anchors. I'm wondering how they will manage to upgrade them - for
| future algorithms without breaking compatibility.
| lxgr wrote:
| What's even more impressive is that this technology has been
| around for decades!
|
| > I'm wondering how they will manage to upgrade them - for
| future algorithms without breaking compatibility.
|
| Just like all other smartcard systems: Very, very slowly.
| Credit and debit payment cards with a smartcard (EMV) chip have
| similar issues - even small patches take multiple years due to
| the relatively long average card validity.
| Muromec wrote:
| Passports and money are quote complex to be forgery-resistant.
| With internet existing it turns out, it's easier to discard the
| physical form altogether and only leave pure chain of trust
| digital form.
|
| It already happened to money, it is slowly happening to
| passports and ids too.
|
| > I'm wondering how they will manage to upgrade them - for
| future algorithms without breaking compatibility.
|
| The same way as always -- introduce a new version of the
| passport, which can as well be verified through a completely
| different system altogether.
| tonymet wrote:
| Washington State "Enhanced ID" (which is also REALID compliant)
| was one of the first DHS-approved IDs from way back in 2005 . Ari
| Jeuls et al (see below) found a number of vulns including remote
| cloning and remote disablement, publishing their findings a few
| years after the launch.
|
| I talked to WA DOL Privacy Officer about it a couple years ago,
| and found that the tech platform had remained unchanged. WA
| maintains the printed material and DHS maintains the RFID package
| which is over 20 years old now .
|
| Think of other 20 year old tech and how safe you feel having that
| in your wallet.
|
| https://www.arijuels.com/wp-content/uploads/2013/09/KJKB09.p...
|
| Edit: clarified Enhanced ID because there are differences in the
| program
| mothballed wrote:
| Enhanced ID allows border crossing for most cases covered by
| the passport card, while real ID does not, for reasons that are
| unclear to me.
| tonymet wrote:
| My understanding is that you can be RealID compliant without
| checking for citizenship. And in theory RealID doesn't have
| to have RFID in the chip. Enhanced ID has to have both of
| those requirements.
| khuey wrote:
| I can't speak to the technical side of things but legally
| for a state to issue a REAL ID they have to verify that the
| person is allowed to be in the US at the time of issuance,
| not that they are citizens, and, if applicable, they have
| to shorten the validity of the ID to the period that the
| person is expected to be allowed to be in the US.
| lxgr wrote:
| Nice overview, although it seems to be missing one of the most
| important changes from AA to CA: AA uses signatures for
| challenge/responses, which are by definition non-repudiable.
|
| This means that any second party with access to your passport can
| prove to any (unaffiliated/untrusted) third party that they had
| access to your passport and can even include something like a
| cryptographic timestamp to prove that they did so at a given
| point in time.
|
| There were even some experimental schemes explicitly making use
| of ICAO biometric passports as a "proof of personhood", as far as
| I remember, but given that the ICAO scheme does not have any
| notion of document holder consent (e.g. via a PIN or other means
| of authentication), there are also significant privacy and
| security problems.
|
| CA intentionally avoids all of that, since the risk of entities
| using ICAO passports as unintentional and insecure digital
| signature tokens was apparently deemed too high.
| wartywhoa23 wrote:
| But what kind of cryptography makes it mathematically impossible
| for bribed officials to issue perfecly legal and
| cryptographically protected fake passports, and if none, then
| what problem do electronic passports actually solve other than
| creating even more opportunities to surveil common people?
| lkurtz wrote:
| Cryptography is a tool that turns arbitrary problems into key
| management problems. It doesn't solve problems, but it
| constrains them in useful ways.
| jakobnissen wrote:
| That's an overly cynical take. Obviously it means that a
| criminal organization would need to recruit officials before
| they could issue fake passports. Which is already pretty hard.
|
| And maybe they would need to recruit multiple officials across
| multiple agencies. And if these agencies has internal policing,
| then even if they manage to do that, they now have another
| vulnerability where the criminal operation can be discovered
| and sabotaged.
| SR2Z wrote:
| Here is a list of trivially obvious ways that they solve
| problems:
|
| 1. They can be read significantly faster, or even
| automatically, which cuts down on long border control lines
| even when the biometrics are not used.
|
| 2. They are significantly harder to forge without the consent
| of the issuer, even for other nation-states.
|
| 3. They can store biometrics that allow the bearer's identity
| to be verified automatically and with a very high degree of
| confidence.
|
| I am all for being skeptical of the government's actions, but
| passports are a ridiculous place to have such a strong kneejerk
| reaction. You're already on a list and your movements are being
| tracked. ePassport features are only more convenient when
| compared to older passports.
| alibarber wrote:
| Usually some state's passports grant the holder more privileges
| than those issued by another state precisley because of the
| perceived risk of them being (not) obtained by fraud. Your
| genuine Sealand passport is less practically useful than a
| genuine Finnish one for use in the context of international
| travel.
|
| The cryptography aspect is basically preventing the corrupt
| Sealand government official from stamping out ones that might
| be confused for, for example, a Finnish one.
|
| Sealand[1] being used as an example least likely to cause
| offense - but you can understand that most governments around
| the world really do want to ensure that they are the only ones
| issuing their passports, and hence what that means for their
| citizens.
|
| [1] https://en.wikipedia.org/wiki/Principality_of_Sealand
| miki123211 wrote:
| 1. It's easier to centralize cryptographic cert issuance than
| passport issuance.
|
| You may allow embassy personnel to issue passports, while still
| requiring a computer system in the homeland to verify that the
| person actually exists in some government register (and that
| photos match) before the certificate can be issued.
|
| If you give embassy personnel blank passport templates, they
| can issue passports with completely fake identification
| details, for people who have never existed. The moment
| computers get into the mix, that may no longer be possible, or
| at least leave an audit trail.
|
| 2. There's no risk of surveillance. Reading data from the chip
| still requires you to read the MRZ, so you can't do that
| remotely.
|
| There's nothing a chip gives you that you wouldn't get from a
| normal passport (beyond a very easy and hard-to-fake way to
| verify that the passport is authentic).
| michaelt wrote:
| For one thing, with printed passports border officials have to
| recognise all the anti-fraud features on all the passports
| issued worldwide in the past 10 years.
|
| Quick, what security image on a valid UK passport - a thistle,
| a daffodil, a rose, a clover, a coat of arms (but not the same
| coat of arms as on the front cover), a map of the UK, a
| harlequin pattern, a crown, a lighthouse, a pair of bird wings,
| William Shakespeare, an oak leaf, a compass, a marine
| chronometer, the letters UK, the words United Kingdom, a
| Bermuda-rigged boat, a square-rigged boat, a steamship, or the
| holder's birth date?
|
| It's a trick question, you'll find all of them; they changed
| the passport once for brexit, and again after the queen's
| death. And that's just one document from one country. Far
| simpler to just hold it to the reader and get a beep.
|
| For another thing, if you're worried about bribed officials -
| it's much harder to bribe airport border officials if they're
| required to scan every passport into a computer, and match it
| against the airline's passenger list.
| miki123211 wrote:
| > The filesystem architecture is straightforward, comprising
| three file types: master files (MFs) serving as the root
| directory; dedicated files (DFs) functioning as subdirectories or
| applications; and elementary files (EFs) containing actual binary
| data.
|
| AFAIK, this is the exact same protocol used in all other kinds of
| smart cards, including credit / debit (EMV) chip cards, both
| standard and contactless, as well as SIM cards.
|
| Not sure whether public transit, employee ID and TV cards use it
| too, but I wouldn't be surprised.
| miki123211 wrote:
| So, if I understand this article correctly, if a single terminal
| private key ever leaks, all the protections preventing any random
| passer-by from reading your biometric data go out the window[1].
|
| You could partially mitigate such a weakness by including "not
| valid before" and "not valid after" timestamps in the
| certificates, which would have to be short-lived. Passports would
| then verify that the timestamp supplied by the terminal is in the
| correct range, as well as that it is greater than any previous
| timestamp this passport has ever recorded.
| salviati wrote:
| This would also add the requirement of an accurate internal
| clock.
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