Brute force a TrueCrypt volume password with a known list on Mac OS X (works similarly on linux/ubuntu)

How to bruteforce a TrueCrypt volume

# First you need to know the name of your TrueCrypt disk. In this example, after running the `diskutil list` command, 
# you can see that my 2TB TrueCrypt disk is mounted at /dev/disk2, and the encrypted partition is named "disk2s1" 
# (see the IDENTIFIER column). That's the name I need to use in the ruby script.

$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *251.0 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:          Apple_CoreStorage                         250.1 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                  Apple_HFS Macintosh HD           *249.8 GB   disk1
                                 Logical Volume on disk0s2
                                 3577AD73-007A-460D-BD6A-047FB4A2E189
                                 Unlocked Encrypted
/dev/disk2
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *2.0 TB     disk2
   1:                 DOS_FAT_32                         2.0 TB     disk2s1
   
# Next, download and run the ruby file with your list of passwords after the "passwords = <<END" line, and before the next "END"
# The script will try mounting the volume with each password in your passwords array. You can get clever with things like
# Ruby's Array#product to automatically generate a lot of passwords.

truecrypt-bruteforce.rb

# run this file with:
# ruby truecrypt-bruteforce.rb

# disk name found from the `diskutil list` command
disk = "/dev/disk2s1"

# enter the passwords to try between the two ENDs, one per line
passwords = <<END
letmein
abc123
123456
END

passwords = passwords.split("\n")

p passwords

passwords.each do |password|
  puts
  puts "Trying #{password}"
  cmd = "sudo /Applications/TrueCrypt.app/Contents/MacOS/Truecrypt --text --non-interactive --password=#{password} --mount #{disk} /Volumes/TrueCrypt"
  if system(cmd)
    puts "password found! It's #{password}"
    exit
  end
end