I have finished downloading all of the disk images for Fedora Core 4 on my mac. I wanted to verify that the files were not corrupted. Fedora provides the sha1 checksum for each of the images for this purpose. Mac OS X doesn't provide md5sum or sha1sum tools at all. Fink does provide a way to install md5sum, but not sha1sum.
This web site provides a small package that includes md5sum, sha1sum, and ripemd160sum, I was able to compile it just fine. The only problem that I had was during the "make install" step the Makefile attempted to set the owner to a nonexistent one in Mac OS X. Even with that problem the programs work fine.