> $ echo -n foobar | openssl dgst -sha256 -hex -hmac aabbcc > (stdin)= 6e74cdc3b72b8b66535b914357c7d656a22acbb1700b4e6de688fd5c091d305c This gets posted every once in a while -- google around. Something about the hmac switch not doing what you think it's doing. $ echo -n foobar | openssl dgst -sha256 -mac HMAC -macopt hexkey:aabbcc (stdin)= 985343745ee86b452c7c0b327171829c77e1a022f423d95156b52fa22083db8e BBB