Plan 9 from Bell Labs’s /usr/web/sources/contrib/fgb/root/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.