Re: Help needed with encryption algorithm


Nemok wrote:
> Writing my own encryption (strong) is proving to take more time that I
> have thought. What I need is a small, portable (in C\C++) encryption
> algorithm for encrypting strings, that has a small output (encrypted
> string) that is the same length (or a little bigger) as the original
> 'to be encrypted' string. AES is not an option because I need something
> that doesn't have fixed block sizes and key sizes and is somewhat
> smaller in size. I don't need something too advanced or theoretically
> unbreakeable.

AES doesn't have to be used in a CBC/ECB style mode. CTR would give
you a flexible ciphertext size.

Also I don't get the "smaller key size" bit. Bits are cheap [one good
quote from Bruce]. How will using a 128-bit key cost dramatically more
than say a 40-bit key? That said you can always zero pad the key and
use the resulting string for AES [I'd just repeat the key itself but
zero pad should be ok too].

Of course I'd just use 128-bit at a minimum regardless...

As for "too advanced" that's why you use a crypto library. I'd also
suggest you read up more on the subject matter before you field
anything.

Tom

.

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