OTP Software (Python)
http://www.red-bean.com/onetime/
This kind of thing seems to work:
./onetime -e -n -p pad.dat < cleartext.dat > ciphertext.dat
./onetime -d -n -p pad.dat < ciphertext.dat > cleartext2.dat
sha256sum cleartext.dat cleartext2.dat
Where: pad.dat was created like:
dd if=/dev/urandom of=./pad.dat count=1
Good OTP Jump Link to other possibilities
http://www.hacker10.com/encryption-software-2/list-of-one-time-pad-encryption-programs/