Notes posted by gabetax

String#crypt uses your platform's native implementation

Which cipher types (specified through the salt argument) are available will depend on what your platform natively supports. It should be noted that OSX up to at last 10.6 only provides the regular DES cipher. On most Linux platforms, however, you should have access to the following:

ID  | Method
---------------------------------------------------------
1   | MD5
2a  | Blowfish (not in mainline glibc; added in some
    | Linux distributions)
5   | SHA-256 (since glibc 2.7)
6   | SHA-512 (since glibc 2.7)

So on OSX, you might have:

ruby-1.9.2-p180 :001 > "password".crypt("$6$somesalt")
 => "$6FMi11BJFsAc" 

But on Linux, you’ll get:

irb(main):001:0> "password".crypt("$6$somesalt")
=> "$6$somesalt$A7P/0Yfu8RprY88D5T1n.xKT749BOn/IXBvmR1gXZzU7imsoTfZhCQ1916CB7WNX9eOOeSmBmmMrl5fQn9LAP1"

For more information on what your platform supports, see `man crypt`