I've been working on my own implementation of SHA-1 hashing function. In the bigger picture I've put together a mostly working OAuth client using Groovy, and part of that is using HMAC-SHA1 to compute a secret value. Well I started by using the built in Java version but decided i would create my own... this is good exercise.
So first thing I did was write some unit tests. I needed SHA1 hashes to start with to make sure that my algorithm implementation works. The obvious choices are either sha1sum or openssl. I'm on a iMac running Leopard, and by default openssl is installed. I used that to compute some hash values. Unfortunately for me I spent a lot of time trying to get my algorithm working when it was already working. The problem was I computed the values wrong with openssl. I used the following:
echo "the quick fox jumps the brown dog" | openssl sha1
Which gave me a incorrect value. Why you ask? Well I didn't remember the -n flag and a newline character was being included in the string passed to openssl. Ooops! Well once I added the -n flag everything was fine and I now have a number of hash values to use in my tests.