Creating custom algorithms

east-tec DisposeSecure gives you the opportunity to develop and use your own data-destroying algorithms, that perfectly suit your security needs.

There are two ways in which you can create custom algorithms: you can either use the method editor, or manually edit the method source file.

1) Using the Method Editor

A user-friendly graphical interface that allows you to create new sanitize methods (algorithms) or modify existing ones. The method editor window lets you specify the following information about a sanitize method:

Method Name – defines the name of the method you create. It will appear in the list of the available sanitize methods of east-tec DisposeSecure.

Order – used to determine the place of the new method in the list of the already available methods. The list of methods is sorted based on the information provided through this field. You can also assign non-consecutive numbers, such as 10, 20, 30, … . This way, if you decide to create a method that should be placed between the methods with order IDs 10 and 20, you can assign it a number between 10 and 20.

– The passes list box shows the sanitizing passes you have defined for this method. One pass is sufficient to stop software recovery tools. Several passes might be needed to stop hardware recovery tools.

– The pass type (or the sanitizing pattern) is the pattern used to overwrite the data. You can choose between:
– a fixed byte pattern (e.g. 00, FF, etc.)
– random bytes between two values
– random pattern between two values

– the complement of the previous pass

Sanitizing direction – used to change the default sanitizing direction just for the selected pass. In this case, the next pass will be performed by sanitizing the drive in the opposite direction. Please refer to sanitizing options to find out more about this.

Execution order – used to mix the order of the passes indicated by the interval defined by the two values

Description – a description of the sanitize method

2) Manually editing of method source file

To create o custom algorithm, please open a text editor, write the method and save the file with a .met extension in the METHODS subdirectory of the DISPOSE directory.

Bellow, you will find an intuitive example on how to create your own algorithm for data destruction (the character # indicates a comment line):

# The NAME keyword is used to define the name of the method you create. It will # apear in the list of the available sanitize methods of east-tec DisposeSecure. NAME=Example (6 PASS) # The METHODNR keyword is used to determine the place of the new method in the
# list of the already available methods. The list of methods is sorted based
# on the information provided through METHODNR. By default, METHODNR is equal
# with the number of passes of the method.
METHODNR=8
# The DESCRIPTION keyword defines the method description.
DESCRIPTION= This method is an example.
DESCRIPTION
# The HEXA keyword can be used to create a new pass of the sanitize method. It
# defines a pattern of data (that is a stream of hexadecimal values) to be
# written to the disk. Each value must start with the a “$” character and must
# have two digits.
# pass 1: overwrites the disk with the AAh pattern
HEXA=$AA
# pass 2: overwrites the disk with the 00h ffh patterns
HEXA=$00$ff
# The CHGDIR keyword is used to change the default sanitizing direction just
# for the previous defined pass. In this case, the second pass will be
# performed by sanitizing the drive with 00h ffh paterns from back to front.
# please refer to sanitizing options to find out more about this.

CHGDIR

# The RAND keyword can be used to create a new pass of the sanitize method. It
# generates a stream of pseudo-random numbers between two indicated values
# (written in hexa-decimal form) to be written to the entire disk. Both values
# must start with a “$” character and must have two digits.
# pass 3: overwrites the disk with random patterns
# between 00h and FFh

RAND=$00$ff

# The RNDCH keyword can be used to create a new pass of the sanitize method.
# It generates a random character between two indicated values (written in
# hexa-decimal form) to be written to the entire disk.
# pass 4: overwrites the disk with one random character between 10h and 99h.

RNDCH=$10$99

# The INV keyword can be used to create a new pass of the sanitize method. It
# generates the binary complement of the data generated in the previous pass
# to be written to the entire disk. NOTE: The INV keyword can not be used
# after the RAND keyword.
#pass 5

INV

# The SHUFFLE keyword is used to mix the order of the passes indicated by the
# interval defined by the two values.
SHUFFLE 2 4
appear