Wednesday, December 01, 2021

Okular PDF digital signature improvements coming "soon" thanks to NLnet

Starting on January I will be working on a project named "Improve Okular digital signature support" that has received a grant from the NLnet foundation as part of the NGI Assure fund.

This will allow me to work part time on Okular (in case it's not clear I work on Okular on a "when I have time-hobby" basis right now), the planned improvements are:

1. Support for signing unsigned signatures. I know it sounds confusing, think about it like something like the old "sign here" boxes on printed paper forms.

2. Support digital signatures in the Okular Windows version

3. Make signature text support all character sets

4. Write Okular-mobile user interface to show signature status

5. Support digital signatures in the Okular Android version

But I'm hoping to squeeze some other signature related improvements in, if you have a particular favourite please leave a comment.

Thanks to NLnet for trusting me on this, and also thanks to my current employer (KDAB) for allowing me to work less hours for a few months so I can take on this project.


R. said...

Hi Albert,

Support for hardware tokens, if possible. There are a number of hardware tokens which Firefox can load at run time (not stored in PKI database).

A simple use case: user plugs in the hardware token, and loads a specific module (library) in Firefox security devices and logs in. Open a pdf in Okular and be able to sign with this token.

victorhck said...

Congrats dude!!!

Filipe Saraiva said...

Great Albert, this project is very important to increase Okular adoption mainly in enterprise environments. Nice!

Would be possible to allow the addition of signature by "image", like a stamp? Some use cases for "digital signature" can be covered simply adding an image, without take care of criptography keys, etc. Something similar to what Xournal++ allows [1].

All the best!


Anonymous said...

That would be great! I'm glad and happy to hear that - I hope you'll get it done.

Regards and thanks

Unknown said...


great to see progress in the signature area :-)
Since you requested additional bugs that could be fixed - i have two that i would like to throw into the ring:

Fixing UI stuff is nice, however if the forms do not work properly this will render okular useless for various use cases (as populating forms with it).

See also the pull requests that already exist - you could also continue working on them, i guess the original GSOC author will not come back to work on these tickets:

Thanks for you great work!

Unknown said...

Awesome to hear this! \o/

Albert Astals Cid said...

@R I don't have any hardware token to try, but I've been told that if you configure the nssdb properly it just works (i.e. if it works in Firefox it should work here)

toni v said...

Hola Albert
Estic intentant configurar l'okular des de debian10 per poder signar documents pdf però no veig les opcions a la finestra de les eines...
S'ha d'instal·lar algun mòdul a banda?

Albert Astals Cid said...

Debian 10 és infinitament antic.

Si té soport de flatpak pots provar amb