Panic passwords are dangerous, as there's a risk the attacker has a copy of the encrypted data prior to demanding a decryption key. That's why Truecrypt etc prefer plausibly-deniable systems involving fake containers revealed by a panic password: they crack the container and find something plausibly sensitive, but not what they're seeking.

On 12 May 2014 10:46:34 GMT+01:00, rysiek <rysiek@hackerspace.pl> wrote:
Dnia niedziela, 4 maja 2014 21:27:06 Jose Damico pisze:
Hi All,

I've developed 2 small/simple/open-source Android apps that can be
useful for data protection in mobile devices:

=============

Yapea: Yet Another Picture Encryption Application

https://play.google.com/store/apps/details?id=org.jdamico.yapea
https://github.com/damico/yapea

=============

SecNote: Encrypted Notepad for Android

https://play.google.com/store/apps/details?id=org.jdamico.secnote
https://github.com/damico/SecNote

=============

Both applications, has these features:

* Encryption Algorithms:

Symetric encryption:

AES (CBC/PKCS5Padding)
Blowfish (CFB/NoPadding)
The Initialization Vectors are generated based on unique data
from the smartphone.

Which data?

* Type of encryption key:

Length: 256 bits

Generated through key derivation (from user-defined password)
with PBKF2 algorithm. The salt are generated based on unique
data from the smartphone. The key is stored inside a
configuration file, at smartphone file system. This file is used
for password verification at first time of application use.
After that the key is encripted and stored inside smartphone
memory (cache). But at anytime the user can choose to delete the
encrypted key from memory (Clear cache).

* Application reset: At anytime the user can choose to dump ALL
application data, including encrypted images and configuration.

* Panic password: A password that can be used to delete all encrypted
images. In a case where user is forced to give its key. (If you're
traveling overseas, across borders or anywhere you're afraid your
smartphone might be tampered with or examined).

That's neat, good thinking!

* Languages: English and Portuguese

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.