ref: f6eacf471e61b188607690e4cdc28a2d94f7db14
dir: /sys/src/ape/lib/openssl/crypto/aes/README/
This is an OpenSSL-compatible version of AES (also called Rijndael). aes_core.c is basically the same as rijndael-alg-fst.c but with an API that looks like the rest of the OpenSSL symmetric cipher suite.