Using Academic Signature under TAILS:

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Motivation:
Presently the "Highest End Security" against US and other government agencies may be using Academic Signature for document enciphering and exchange under TAILS .(Please excuse my hubris, but this is what I believe.) Using TAILS is somewhat inconvenient, so you may want to use this only if you suspect you are specifically and personally targeted by any of these organizations.
As we know today this doesn't only happen to the bad guys but unfortunately also to very honorable people.
Apparently nowadays it doesn't take more than to google for TAILS or TOR just once to be labeled as extremist by the US administration. From there it might be a very short step to being labeled as terrorist.

How To:
Since TAILS is based on a seasoned Debian and I develop Academic Signature on a recent Ubuntu(based on a recent Debian), chances are my binaries won't run on TAILS because some libraries don't match.
You will have to compile Academic Signature yourself in a persistent folder in this case under TAILS.
(Thanks Dirk for pointing out some issues, I tried to address them and included some of your comments below.)

1) Preparations
a) Set a root password on booting TAILS.
b) Make sure to have a persistent folder on your TAILS.
c) Download the Academic Signature source archive and my GnuPG signature to the persistent folder.
d) Check my GnuPG Signature of the Academic Signature source.(GnuPG is included in TAILS).
e) Unzip the source archive.
f) Run 'sudo apt update' in a terminal.
(optional) Check for the presence of wxWidgets in Tails, e.g., using synaptic.(wxWidgets should be included in TAILS).

2) Set up software environment
Now either:
In Synaptic (Applications, System Tools, Administration), select the following packages:
build-essentials, g++, and libwxgtk3.0-dev.
and install.

Or else:
type in a terminal:
sudo apt install build-essentials; sudo apt install g++;
sudo apt install libwxgtk3.0-dev;

A number of additional dependencies will be taken care of automatically. This will take up about 75Mb of additional disk space.
This step has to be redone, if you want to build aca_sig again in a new TAILS session.

3) Build the executable
Either:
Change to Aca-sig's download directory and call as usual "./configure" then "make".
Upon successful building, you use the local binary and mark it as executable (if neccessary). Installation to the system via "sudo make install" should be omitted since it would only install for this session and would not persist in TAILS - just work with the local copy of the binary and the local helper subdirectories "x_secrets" and "key_tray" in the persistent folder.

Or else:
3 b) Change to Aca-sig's download directory and directly call the hand-made makefile "make release".
Depending on the the version of Debian your TAILS is based on, you may or may not have to delete the explicit link to lX11 in the makefile to successfully build Academic Signature. This is a recurrent nuisance in wxWidgets.


Upon successful building, you use the local binary and mark it as executable. Installation to the system via "sudo make install" should be omitted since it would only install for this session and would not persist in TAILS - just work with the local copy of the binary and the local helper subdirectories "x_secrets" and "key_tray" in the persistent folder.
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Both methods work for me with the current TAILS 4.11 without problems.

You may want to get some practice with TAILS (and Academic Signature, TOR, GnuPG,...) even if you are not specifically targeted. This would be a useful exercise to be prepared for the worst ...
As I read in a discussion forum: The Gulags and KZs of the 20th century were full of innocent people who had "nothing to hide".

May honesty, openness, tolerance and democracy prevail,
we don't need Orwellian thought control by administrations that ordered torture,
let known torturers run around on the loose,
and tell the world about "values".

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