You shouldn't implement HMAC yourself, of course. I repeat: you should not do this. However, if you read Wikipedia on HMAC, you'll find that HMAC is in fact pr

You shouldn't implement HMAC yourself, of course. I repeat: you should not do this. However, if you read Wikipedia on HMAC, you'll find that HMAC is in fact probably one of the easier crypto primitives to understand and implement (as a TOY project). As long as you do the padding thing exactly as specified. But really, use a library.