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There's also a word play in the title. "AES" transliterates to "АЭС" (acronym for " А томная Э лектро с танция") in Russian (and some other Slavic languages), which means "nuclear power plant". Thus, the "☢" sign.
That was a great read. I saw the title and figured it would quickly go over my head but it's all pretty understandable. Does anyone know where I can download the src to have a look through? Edit: found it https://code.google.com/p/corkami/source/browse/#svn%2Ftrunk...
What's the benefit of AES using such small blocks?
Cool trick, I have encountered something like this in a steganography wargame before, the only difference is they used Base64 encoding on the original picture instead of AES :)
What's the benefit of AES using such small blocks?
The block size of a symmetric cipher will generally be in the neighborhood of the key length. You can imagine the problem if you had a 128-bit key but an 8-bit block size -- for each of the 256 possible inputs you would have only 256 possible outputs. There would be multiple keys that produced the same mapping and you could produce every possible mapping with only 65536 keys. So the block size needs to be near the ke…
> So the block size needs to be near the key size
Note that AES-256 has a 256 bit key, but the block size is 128 bits, which is not near the key size.
I believe that the main constraint on block size is that a small block limits the length of messages you can safely encrypt with a given key. If the bad guys see a lot of cipher text encrypted with the same key, they have a better chance of a successful attack. What "a lot of cipher text" means depends on the block size. The bigger the block size, the more cipher text is needed to constitute "a lot of cipher text".
Earlier quoted context omitted.
The block size of a symmetric cipher will generally be in the neighborhood of the key length. You can imagine the problem if you had a 128-bit key but an 8-bit block size -- for each of the 256 possible inputs you would have only 256 possible outputs. There would be multiple keys that produced the same mapping and you could produce every possible mapping with only 65536 keys. So the block size needs to be near the ke…
This doesn't sound right to me. There are 256! permutations of the set {0, 1, 2, 3, ..., 255}. 256! is much bigger than 2^128, so I see no reason that each key cannot produce a unique mapping. > So the block size needs to be near the key size Note that AES-256 has a 256 bit key, but the block size is 128 bits, which is not near the key size. I believe that the main constraint on block size is that a small block limit…
Where do you store the IV? Do you just append it at the end of the file?
http://corkami.googlecode.com/svn/trunk/src/angecryption/ang...
Cool trick, I have encountered something like this in a steganography wargame before, the only difference is they used Base64 encoding on the original picture instead of AES :)
Base64 is not true encryption, it doesn't require a key it is merely obfuscation.