monline

I already posted about HashTab, a utility available for both Windows and Mac OS X. It integrates well with the OS and allows you to generate MD5 (or other) checksums easily. There're a couple of alternatives in case of Windows though.

HashTab makes it easy (using context menu items in Mac's Finder and Windows' Explorer) to generate all kinds of checksums of a selected file (unfortunately it does not support multiple file selections). In v1.2 of the Mac port the following hash functions are available: CRC32, HAVAL (32-3, 32-4, 32-5), MD2, MD4, MD5, RIPEMD (128, 160, 256, 320), SHA (1, 224, 385, 512), Tiger, Whirlpool. My personal favourite is Whirlpool, but for file integrity checking MD5 became the defacto standard, ie. this is the one you'll most likely encounter on download pages.

As a developer/admin, sometimes you might have to generate the MD5 hash of a string. Eg. last time I had to do this, when I installed the admin interface of XCache on a server. I had to create an MD5 of the admin password and put it into xcache.ini. The docs said that I should create a PHP file with something like <?php echo md5('the_password'); ?> to get the MD5 hash. However there's a much faster way, a simple command line.

A Debian server of a pal of mine got suspected of being compromised based on some log entries. Since I have not done something like this before, my first thing to do was looking for sources of information on the subject. Here's what I came up with.

Good to know: the md5sum and sha1sum tools are in the coreutils package, thus they're installed by default on most Debian (or derivative, like Ubuntu) based systems.