Hi Andre,

nice entry. Thanks for sharing the code.

Andre, I think it’s useful.

This kind of cipher as you explain seems simple and efficient, just what a lot of mobile developers needs to give to their applications the option for data to be “unreadable by others”.

I am thinking to those that I am developing: naijanimi (at projects.forum.nokia.com/naijanimi; restricted access) It is at an early stage but I should (to be clear: I SHOULD ;) ) go ahead very fast this next w.e. The encryption capability, not really required by the customer, is missing but needed: it is an application to send free SMS and some data (just user and login, phone number etc) are saved on the phone and if they are encrypted it is best.

Edit: make link into real link, and added note on restricted access to page; Andre

I am glad people seem to appreciate the snippets I have posted so far.

Andre wrote:

Would it be useful to add a section discussing the actual algorithm used in the class?

Does anyone think it is possible nessecairy to document this in more detail in the article?

Hi Andre, I can if you explain to me a bit more what do yo have in mind. What I am thinking is to use this class in an application that I am building in these days, so the reference code can became a set of snippets for users that want to use, while the application itself can be a usage sample (it is shared on projects.forum.nokia.com/najianimi). The informations can be collected in the wiki integrating the page you have already wrote.

I’m not sure the page needs a lot of snippets illustrating the use. It seems quite clear to me. Or do you think it needs more examples?

Andre, I was no clear in my thought. The page is clear, as is, with the snippet. I agree that a wiki page with too much code became confusing. What I mean is that integrating your page, with a little more documentation about encryption and a project that can be an example (that use in a precise vode source your class) can be useful.

Usually what I find in documentation on the net regarding encryption or similar, is too much code or too much teory.

thank you Andre , a very good work

Sure ! :) It’s a great starting point.

Nice entry Andre.

I am currently working on a version 2, with these added features:

• optional integrity checks using a checksum or a cryptographic hash
• error reporting
• slightly higher security due to added random character. That should make it harder to guess the first byte of the key based on the fact that there are only a limited number of characters used normally. Should increase effective key length by an guestimated 3 bits.

I have just uploaded a modified version that implements the above features.

I am waiting in the shade… When I start (hope tomorrow) I can get the last version :)

If you miss the documentation tools discussion: I’ve split it out to a new thread [developer.qt.nokia.com]

I have added a separate page [developer.qt.nokia.com] that details the algorithm and the layout of the cypher text. Of course, I also added a link from the main page.

Hi Andre,
First: Thanks for sharing the code.

Second: You’ve got some typos in the Example usage code.

• Name of the Class: SimpleCypt —> SimpleCrypt
• crypto.setCompression(SimpleCrypto::CompressionAlways)
  • crypto.setCompressionMode(SimpleCrypt::CompressionAlways);
• crypto.setIntegrityProtection(SimpleCrypto::ProtectHash);
  • crypto.setIntegrityProtectionMode(SimpleCrypt::ProtectionHash);
• SimpleCrypt.ErrorNoError —> SimpleCrypt::ErrorNoError

Third:
The String Encryption and Decryption works fine, but for the binary version I seem to be having some difficulties.

my main.cpp

My Output (console):

“??Sß+”
“”
“”

What have I missed or using incorrectly?

Thanks again for the contribution.