ddsum
=====

Inspired by dd5sum, ddsum includes the following features:

 * Support for md5, sha1, sha224, sha256, sha384 and sha512 (plus any
   additional digests provided by OpenSSL)
 * Read source data and write it out while computing a message digest
 * The ability to compute multiple message digests with one-pass of the source
   data
 * Verify that a message digest matches the data you have

Example:

$ ssh [email protected] 'dd if=/dev/sdb | ddsum -h sha256' 2>sdb.img.sha256 | dd of=sdb.img
$ ddsum -c sdb.img.sha256 < sdb.img

This would compute a sha256 message digest of /dev/sdb on example.com and then
check that the data we wrote to sdb.img matches the message digest that was
previously generated.

Requirements
============

python >= 2.2