On Fri, 14 Jan 2022 20:50:57 +0000 Стефан Васильев <stefan.vasi...@posteo.ru> wrote:
> Stuart Longland wrote: > > > On Fri, 14 Jan 2022 17:54:56 +0000 > > Стефан Васильев via Gnupg-users <gnupg-users@gnupg.org> wrote: > > > >> > If QR is an option, why not encode the entire message in QR? > >> > >> I thought about that too, but in case the document would be several > >> pages long and would not fit into a QR-code. Ok, one can split the > >> large document and insert then several QR-codes into one Fax page. > > > > I've experimented with using QR codes with OpenPGP on-and-off… mostly > > as a mechanism for sharing the public keys: the idea being that you > > could have business cards printed up with the back side containing a QR > > code of your public key (not a fingerprint, the actual key). > > > > In my experience, it is very hard to get the big and complex QR codes > > to scan reliably. Some of the QR codes used for COVID-19 contact > > tracing and vaccination status _really_ push the limits -- with those > > largish codes often failing to scan. > > > > ECC keys could be made small enough to have a snowflake's chance in > > hell of working. 4096-bit RSA was a no-go. > > Thanks for sharing your experience, much appreciated! > > > There are schemes for encoding an image for printing onto a piece of > > paper and later scanning it back in to recover the original data. QR > > code is obviously a more recent option, but was not the first. These > > may be worth pursuing. > > Would you like to explain a bit such schemes? I am aware, for example, > that GnuPG on a mini offline laptop can beat *all* smartphone crypto > messenger, when it comes to endpoint security, when used with a dumb > phone with a USB port and while sending GnuPG MMS messages. All > users need for that is a software from GitHub, which can convert GnuPG > messages to .png images and back. Simply search there for 'imgify'. https://github.com/dmshaw/paperkey/ is one such scheme, intended for making a private key back-up. It could probably be adapted to store arbitrary data. There may be others, I just can't put my finger on them now. -- Stuart Longland (aka Redhatter, VK4MSL) I haven't lost my mind... ...it's backed up on a tape somewhere. _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users