dcfldd - enhanced version of dd for forensics and security
dcfldd is a modified version of GNU dd. The major features added are hashing, fast disk wiping (through patterns) and status output.
dcfldd was originally created by Nicholas Harbour from the DoD Computer Forensics Laboratory (DCFL). Nick Harbour still maintains the package, although he is no longer affiliated with the DCFL.
Send any feature requests or ideas to the author at nicholasharbour@yahoo.com.
On https://github.com/adulau/dcfldd/, this is the latest version of http://dcfldd.sourceforge.net/ (1.3.4-1) including Debian patches and some additional patches from Alexandre Dulaunoy https://github.com/adulau.
dcfldd if=/dev/sda hash=md5,sha256 hashwindow=20G md5log=md5.txt sha256log=sha256.txt \
hashconv=after bs=512 conv=noerror,sync split=20G splitformat=aa of=sda.dd