Show HN: Air-gapped file encryption as self-decrypting HTML page

DylanMerigaud | 20 hours ago

Self-decrypting HTML? That's an innovative approach.

[OP] emurlin | 20 hours ago

Yeah, I was inspired by self-extracting archives. I wanted to share files with basically no dependencies.

The goal was:

1. Something that didn't require any installation (assuming a web browser)

2. Have a single file with no network that could self-decrypt

3. Be fully auditable

The second point is done by having (sort of(*)) reproducible builds and embedded OpenPGP signatures.

The first point is made by cleverly manipulating the HTML structure so that it can decrypt without breaking the PGP signature. It can even decrypt using bare openssl (which was a design goal too, though getting the exact structure right took some work and bug reports).

The third point is accomplished by the first two, and by the source being freely available.

(*) Depends on the OS at the moment.

dang | 9 hours ago

I'm going to move this description to the top and re-up the post - I hope that's ok!

112233 | 9 hours ago

Somebody already has copied this innovative approach and travelled to past apparently: https://acme.com/software/securepage/

jszymborski | 8 hours ago

Methods like these go way further back than 2010... I recall one that had a reward promised if you could break it.

EDIT: Here's a patent from 2006 [0]

[0] https://image-ppubs.uspto.gov/dirsearch-public/print/downloa...

FatalLogic | 20 hours ago

Maybe this is the source?

https://github.com/ApelegHQ/ts-cms-ep-sfx

[OP] emurlin | 20 hours ago

Correct

dang | 8 hours ago

Added above. Thanks!

nikhilkxmar | 13 hours ago

Cool!

lukan | 8 hours ago

I assume the "air gapped" part is merely indicating no internet required?

az226 | 8 hours ago

Offline would be a better word.

firefax | 8 hours ago

cool project!

also does everyone have to enable js to vote, or did i troll too hard? (sorry!)

som | 7 hours ago

A version of this that supported PKE would be cool. So you don't have to share a password in a side channel

kooi | an hour ago

This is great!

Lol @ "airgapped".

technion | 22 minutes ago

I never thought I'd see a browser support list that specifically includes "Dilo" or, in the last few years, "Internet Explorer", but apparently you're comprehensive.

I went to look for unauthenticated CBC mode like every time I see this sort of thing but it's actually GCM mode so, well consider me surprised.