The Ruby Way: Solutions and Techniques in Ruby Programming, Second Edition

2.26. Encrypting Strings

There are times when we don’t want strings to be immediately legible. For example, passwords should not be stored in plaintext, no matter how tight the file permissions are.

The standard method crypt uses the standard function of the same name to DES-encrypt a string. It takes a “salt” value as a parameter (similar to the seed value for a random number generator). On non-UNIX platforms, this parameter may be different.

A trivial application for this follows, where we ask for a password that Tolkien fans should know:

coded = "hfCghHIE5LAM."

puts "Speak, friend, and enter!"

print "Password: "
password = gets.chop

if password.crypt("hf") == coded
  puts "Welcome!"
else
  puts "What are you, an orc?"
end

It is worth noting that ...