Simple encryption or signing of data on propeller?

Steve Jones

Sorry if this should be obvious, but I've done some googling and can't find anything..

I'm looking to communicate with a propeller over the Internet, and I need to be able to sign or encrypt the data, and decrypt or validate a sign on recieved data..· The data isn't going to be secret or sensitive, but I dont want the propeller to act on spoofed data..

Signing would be fine, but if that hasn't been done, and encryption has, then I'll go that way...

These will be small packets, low bandwidth, so speed isnt a concern...

Has anyone seen anything like this done on a propeller?· Any sample code or hints?

-Steve

Phil Pilgrim (PhiPi)

There's an object in the OBEX that allows you to compute MD5 hashes in Spin: obex.parallax.com/objects/321/. You can use that to sign and verify your transmissions.

-Phil

mctrivia

it would be slow but you can easily use the following formula:



if both props start at the same value and iterate after each bit then xoring the received data with the least significant bit will result in a strong encryption.

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24 bit LCD Breakout Board now in. $21.99 has backlight driver and touch sensitive decoder.

Phil Pilgrim (PhiPi)

mctrivia,

Can you cite a reference to back up your claim that your method is "strong" encryption? I have my doubts.

-Phil

mctrivia

http://en.wikipedia.org/wiki/Blum_Blum_Shub

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24 bit LCD Breakout Board now in. $21.99 has backlight driver and touch sensitive decoder.