I'm confused about the latter half of your comment. CCM is basically CTR mode plus CBC-MAC; certainly the adversary isn't meant to have the key to your MAC? (Yo

I'm confused about the latter half of your comment. CCM is basically CTR mode plus CBC-MAC; certainly the adversary isn't meant to have the key to your MAC? (Your comment about open-key use does make sense; it's just that I'm not sure it applies to CCM.) Also, I'll channel your for a moment: don't build your own crypto! And don't use lightweight block ciphers for data you care about: many are designed to skirt the edges of "too weak", their implementations haven't been side-channel-attacked quite as often as OpenSSL's AES, and they haven't been reviewed to anything like the extent that AES has been and/or have been found wanting (TEA). Yes, experts can put them to good use, but be very careful and don't use them before ruling out the conservative AES-HMAC-SHA2 as well as more modern constructions like Keccak in AEAD mode.