Show HN: PanicLock – Close your MacBook lid disable TouchID –> password unlock

Posted by seanieb 9 hours ago

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I wrote this after the case of a Washington Post reporter, Hannah Natanson, was compelled to unlock her computer with her fingerprint. This resulted in access to her Desktop Signal on her computer, revealing sources and their conversations.

https://www.yahoo.com/news/articles/washington-post-raid-pro...

Edit: I've a lot more details about the legality and precedence on the apps landing page https://paniclock.github.io/

Comments

Comment by quicklywilliam 7 hours ago

Great idea and implementation! If you are hesitant to install this for any reason, you can accomplish the same thing with this one liner:

  sudo bioutil -ws -u 0; sleep 1; sudo bioutil -ws -u 1
Edit: here's a shortcut to run the above and then lock your screen. You can give it a global keyboard shortcut in the Shortcuts app. https://www.icloud.com/shortcuts/9362945d839140dbbf987e5bce9...

Comment by alin23 6 hours ago

Hook this to a lid angle below 30° trigger in https://lowtechguys.com/crank and you can easily make it run on a simple lowering of the lid

Comment by Wowfunhappy 3 hours ago

At that point, why not just disable Touch ID?

Comment by hervature 2 hours ago

When the bad guys are too impatient to wait until you leave the computer but not fast enough to stop you before 30 degrees while keeping the convenience of life.

Comment by momentmaker 10 minutes ago

The iOS equivalent is to hold the side + volume button until the power slider shows up. Cancel out of it and the next unlock will require your passcode. Pressing the side button 5x triggers Emergency SOS which does the same thing. Been there forever but barely anyone knows about it.

Nice to see something like this on the Mac side.

Comment by mrdomino- 8 hours ago

Neat idea.

I remember way back in the day, there was some question as to the legality of compelled unlocking of devices; IIRC, it’s been deemed legal to compel a fingerprint, but illegal (under the first amendment?) to compel entry of a password—IIRC, as long as that password hasn’t been written down anywhere.

I gather this is written to that end primarily? Or is there some other goal as well?

Comment by seanieb 8 hours ago

I wrote this after the case of a Washington Post reporter, Hannah Natanson, was compelled to unlock her computer with her fingerprint. This resulted in access to her Desktop Signal on her computer, revealing sources and their conversations.

https://www.yahoo.com/news/articles/washington-post-raid-pro...

Edit: I've a lot more details about the legality and precedence on the apps landing page https://paniclock.github.io/

Comment by dang 2 hours ago

(I've put a copy of this text at the top of the thread, since it's standard for Show HNs to have some intro/background up there. I hope that's ok with you!)

Comment by seanieb 2 hours ago

Thank you!

Comment by mrdomino- 7 hours ago

Cool, thank you.

Comment by Nexxxeh 1 hour ago

There's also the issue that the device is covered in fingerprints, and if you can build a clean image of the print, you can likely manufacture a gelatin copy of that fingerprint that will work on most fingerprint scanners.

I can't speak to the current generation of Apple fingerprint scanners, but historically iirc you can grab a print, clean it up in Photoshop, print it on OHP transparency using a laser printer and use it like a mould to copy a fingerprint.

Comment by xoxxala 8 hours ago

The website has some more info on the biometric vs. password debate and legal situation:

https://paniclock.github.io/

Comment by 6 hours ago

Comment by 420official 6 hours ago

While it's true that the legality of law enforcement forcing passwords in unclear, courts can absolutely force you to enter a password even if it's not written down by holding you in contempt indefinitely.

Comment by xoa 5 hours ago

>courts can absolutely force you to enter a password even if it's not written down by holding you in contempt indefinitely.

This is not true outside of a narrow exception. Indeed this is the core point of the 5th Amendment, to protect you from having to be witness against yourself. It's just as binding on the judicial branch as it is on the executive. Ordinarily, a court may not compel a defendant to testify or say something that could incriminate them.

The narrow exception is the "foregone conclusion doctrine", which allows compelling testimony about specific evidence the government legally knows exists, knows the defendant controls access to, and knows is authentic. All of which has a bunch of caselaw around it. The textbook example is somebody has a device open, and an officer directly witnesses illegal material on it, but before they can seize it the person manages to turn it off and now it cannot be accessed without a password. So the government can say "we witnessed this specific illegal material, and this device is owned by the defendant and we can prove from video that they have accessed the device, and we want access to that specific material". But if you're just crossing the border with a locked device, they cannot compel the password just to search through it, or even if they're suspicious of something specific. They need actual knowledge, either through their own evidence or because the person foolishly talks and confesses something.

Otherwise they can definitely physically seize the device for a time (which could be very inconvenient/expensive depending) but that's it.

Comment by whalesalad 6 hours ago

Take it to the logical end - you can tie up / handcuff / sedate / restrain an individual in order to get their fingerprint (or, ahem, way worse) but you cannot extract a password from someones brain.

Comment by vunderba 5 hours ago

> cannot extract a password from someones brain.

May I introduce you to XKCD Number 538.

https://xkcd.com/538

Comment by stavros 6 hours ago

If it's in scope to "way worse" someone to get their fingerprint, I'm sure I can be very persuasive in getting their passwords.

Comment by whalesalad 4 hours ago

You can get the fingerprint of a dead person... you cannot extract a password from a dead person.

Comment by stavros 4 hours ago

Of course not. You extract it right before.

Comment by freehorse 6 hours ago

This is great. I see many times "security advice" against biometrics replacing password unlock, but most of the time I am more worried about getting recorded by somebody/something while typing a password in the open than anything else. This makes it better for those other cases.

Comment by parl_match 1 hour ago

I've thought the Apple platform has two glaring omissions

- touchid and biometric configuration profiles (standard, paranoid, extra paranoid)

- versioning for icloud backup

The simple fact is that there is no one-sized-fits-all use case for this.

Biometrics are great for the average user! They reduce shoulder surfing and increase security.

But for some users, you might want two factor for biometrics (such as an apple watch), or short windows before password entry is forced. You might want both biometrics AND password entry required. You might want to enable biometrics only when two factor is enabled.

Look, I'm not saying that what I've said is the ideal setup, by the way. Just that there is a lot of room for improvement versus the status quo.

Comment by Terr_ 1 hour ago

At that point what you need is true multi-factor. For example, both fingerprint and per-device PIN.

Regrettably, that's not often offered as a feature, even when the infrastructure is already there.

Comment by akdev1l 1 hour ago

Notably macOS cannot do this

Comment by parl_match 1 hour ago

Careful with absolutist statements :)

macOS can in fact be configured to use a third party idp, including interactive elements, on loginwindow.

So, you could build your own through the ExtensibleSingleSignOn and Extensible Enterprise SSO macOS plugin API. You would do touchid, and then have it pop your own custom window/app, providing a prompt through that API, except it's just a hardcoded value (or some shit idk)

https://youtu.be/ph37Yd1vV-c

So yes, macOS can in fact do that. Just not out of the box. I strongly believe that it is a glaring omission, or at least something they should gate through lockdown mode. idk!

Comment by surround 3 hours ago

> in sensitive situations, law enforcement and border agents in many countries can compel a biometric unlock in ways they cannot with a password.

If the threat model includes state-level actors, then disabling biometrics won't prevent data from being retrieved from physical memory. It would probably be wiser to enable disk encryption and have a panic button that powers down/hibernates the computer so that no unencrypted data remains on RAM.

The website says shutdown "takes time" and "kills your session" but a hibernation button would take effect just as fast and would preserve the session.

Comment by LoganDark 3 hours ago

Apple Silicon is at least much more difficult to attack in this way, though it might be possible.

Comment by jovial_cavalier 3 hours ago

a cop works for "the state," but he's definitely not a "state-level actor."

Comment by surround 3 hours ago

How do you define "state-level actor?" Police departments certainly have access to state and federal forensic resources to access unencrypted data in memory.

Comment by stackghost 2 hours ago

In the context of breaking into phones and laptops, "state-level actor" usually implies a team of people with NSA-type forensic capabilities. That is, they have deep expertise in infosec and related topics, access to 0days that the security apparatus has hoarded and kept secret for their own use, and they may have bespoke hardware to facilitate attacking the device.

A random cop might have access to a Cellebrite machine but they can't just call up the NSA and ask them to break into some drug dealer's macbook.

Comment by surround 1 hour ago

Fair enough. Though they certainly could still break in if the laptop isn't encrypted, so this tool is only useful when combined with disk encryption.

Comment by gruturo 4 hours ago

This would be perfect if it could monitor the force with which the lid is closed (macs have accelerometers after all, either this info or an acceptable proxy could be derived?).

Gently close? no action.

Stronger, faster action? Disable touch ID

Slam shut in full panic? yeah disable all biometrics, lose all state, even wipe the ram and the filevault key if it's an option

Comment by thih9 4 hours ago

Perfect rage quitting machine. There should be an enterprise version: when lid is closed with full force it also sends a professional resignation letter to the current employer.

Comment by QuercusMax 4 hours ago

You must not have cats or children if you think that last one is reasonable

Comment by gruturo 4 hours ago

Ok just unload the filevault key from ram, better? And if possible tell the secure enclave to revert to the before-first-unlock state

Comment by wolvoleo 4 hours ago

I'm surprised Apple doesn't offer an option. On the iPhone you could do this by pressing the power button several times. Not sure if this still works because the iPhone 6 was my last one though.

Comment by bhj 4 hours ago

Pressing and holding Power + Vol Up/Down is the current combo

Comment by dozerly 1 hour ago

Pressing the power button 5 times fast also does it!

Comment by moralestapia 41 minutes ago

This should be an OS X feature, it's just that good.

Great work, congrats!

Comment by rglover 4 hours ago

This is awesome, thank you. Was just thinking about this problem the other day. Glad someone whipped something up.

Comment by ttul 8 hours ago

The 2026 version of "Boss Key".

Comment by p0w3n3d 7 hours ago

What's the rationale? It should be described in the README.md IMO

Comment by seanieb 7 hours ago

That's good feedback. I just added it to the readme:

> "PanicLock fills a gap macOS leaves open: there is no built-in way to instantly disable Touch ID when it matters. Biometrics are convenient day-to-day, and sometimes preferable when you need speed or want to avoid your password being observed. But in sensitive situations, law enforcement and border agents in many countries can compel a biometric unlock in ways they cannot with a password. PanicLock gives you a one-click menu bar button, a customizable hotkey, or an automatic lock-on-lid-close option that immediately disables Touch ID and locks your screen, restoring password-only protection without killing your session or shutting down."

I've more details on the apps landing page - paniclock.github.io

Comment by itsdesmond 7 hours ago

A person might use it to stop someone getting into your computer through certain types of physical coercion, forcing your finger to the reader, or (much less likely but I’m sure security services know how) a copy of your fingerprint.

But it isn’t a why, it is a what. That what is a tool that lets you quickly disable Touch ID for whatever reason you want to.

Comment by deadbabe 1 hour ago

There should just be a way to setup an alternate dummy account based on the finger you use. This gives the illusion of compliance but your real data is safe.

Comment by orthogonal_cube 7 hours ago

Honestly I’m surprised this wasn’t already a feature in macOS. Thank you for coding it and publishing as open-source!

Comment by Forgeties79 7 hours ago

PSA to iOS users: if you tap the lock button 5x it forces password-only unlocking. Useful at protests or any precarious situations with law enforcement.

Comment by ASalazarMX 1 hour ago

- TSA: Hey, bring your bag and devices here. Routine inspection.

- Traveler: [takes phone from the bin] [finds lock button] [click] [click] [click]

- TSA: Hey, stop what you're doing Mr. Terrorist!

Comment by jonpalmisc 6 hours ago

This still leaves your device in an AFU (after first unlock) state, with user data decrypted, and should not be treated as secure.

The only thing you can do (to protect your data from forensics, etc) is to return it to BFU by shutting it off.

Comment by seanieb 6 hours ago

Correct. This is a classic security vs convenience tradeoff. I mention that trade off on the landing page, PanicLock vs Shutdown

> Use shutdown when you can, PanicLock when you can't. Shutting down is the most secure option—but when you need your Mac locked now and you'll be back in five minutes, PanicLock is your answer.

*PanicLock* - Fast "oh shit" button - Lid closed when in transit. - Instant lock (1 second). Disables Touch ID immediately - Preserves your session - Back to work in minutes

*Full Shutdown* - Maximum security - Purges encryption keys - Fully locks FileVault - Takes time to shutdown & restart - Kills your session

Comment by Forgeties79 6 hours ago

Better than nothing and keeps them from having unlocked access. You can do it fast in your pocket.

Comment by chuckadams 7 hours ago

Bringing up the shutdown screen (hold lock and either volume button) will also do it.

Comment by itsdesmond 7 hours ago

I did not know that. That is extremely convenient. Thank you.

Comment by freehorse 6 hours ago

Tapping it 5 (6? 7? 20?) times works better while panicked, though.

Comment by sigio 7 hours ago

On GrapheneOS (and maybe android generic?) this calls the emergency number, I just found out (with a 5 second timer to cancel this luckily)

Comment by nailer 4 hours ago

If someone can force you to use touch id they can probably also force you to enter your password.

(If you’re about to comment about fingerprints on transparency film and balloons filled with warm water then yes good point)

Comment by skillina 28 minutes ago

Capable? Yes. Willing? I wouldn't be so sure. You don't even need to hurt someone to manhandle them enough to put their fingerprint on a scanner. Whereas forcing someone to give up a password could rise to the level of torture.

Of course, I imagine the majority of people would yield their password if you simply threatened to detain them long enough to make them miss their flight.