Overview: https://en.wikipedia.org/wiki/International_Data_Encryption_Algorithm According to wikipedia: "International Data Encryption Algorithm (IDEA) The last patents expired in 2012, and IDEA is now patent-free and thus completely free for all uses." Compile: ./compile.sh Run: time ./target/release/idea_rust e key text output.txt time ./target/release/idea_rust d key output.txt decrypted base64 --decode decrypt

Not for industrial or production use. This is just a PoC.