(Ruby) AES-CMAC

Demonstrates using the AES-CMAC algorithm, which is a keyed hash function similar to HMAC and Poly1305.

Note: Chilkat added AES-CMAC in version 9.5.0.95.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

crypt = Chilkat::CkCrypt2.new()

# Set the MAC algorithm to AES-CMAC
crypt.put_MacAlgorithm("aes-cmac")

# AES-CMAC always uses a 16-byte (128-bit) MAC key.
keyHex = "2b7e151628aed2a6abf7158809cf4f3c"
success = crypt.SetMacKeyEncoded(keyHex,"hex")

# Let's compute the AES-CMAC for the test vector at https://www.rfc-editor.org/rfc/rfc4493#appendix-A
# Here we have 64 bytes in hex representation.
messageBytes = "6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411e5fbc1191a0a52eff69f2445df4f9b17ad2b417be66c3710"

bd = Chilkat::CkBinData.new()
bd.AppendEncoded(messageBytes,"hex")

# Compute the AES-CMAC for the bytes contained in bd and return the AES-CMAC in hex representation.
crypt.put_EncodingMode("hex_lower")
cmac = crypt.macBdENC(bd)
print cmac + "\n";
# Output should be: 51f0bebf7e3b9d92fc49741779363cfe

# Now do the same for a string:
plainText = "'Twas brillig, and the slithy toves\nDid gyre and gimble in the wabe:\nAll mimsy were the borogoves,\nAnd the mome raths outgrabe."
encTag = crypt.macStringENC(plainText)
print encTag + "\n";

# Output should be: 4fca1fcbd265048d247f99ab57fa3ceb