nz.ac.waikato.modeljunit.examples.gsm
Class GSM11Impl

java.lang.Object
  nz.ac.waikato.modeljunit.examples.gsm.GSM11Impl

public class GSM11Impl
extends java.lang.Object

This is a simple Java implementation of the GSM 11.11 standard. This class pretends to be the SIM card within a mobile phone. That is, tt manages the security and the contents of the various files and directories stored within a typical SIM card.

It handles only a very small subset of the files and directories that a real SIM would, supports only CHV1 security, and has many other limitations and omissions. The goal of this class is to illustrate how we can use model-based testing to test such an implementation, and mutation-testing (see jumble.sourceforge.net) to measure the quality of the generated tests.

For example, executing a sequence of 100,000 randomly-generated test steps from the SimCard model takes only about 1 second, but gives 95.2% code coverage of this class and (a more demanding metric) covers 84% of the 298 mutations generated by Jumble 1.0 for this class. (Done with generate(100000), with setResetProbability(0.01), and with all Jumble mutations turned on, except for mutation of class pool constants).

Author:

marku

Field Summary

static int	MF
static int	PERM_ADM
static int	PERM_ALWAYS Constants for file access permissions
static int	PERM_CHV1
static int	PERM_NEVER

Constructor Summary

GSM11Impl()

Method Summary

byte[]	cmd(byte[] apdu) This corresponds to sending a command to the SIM.
protected boolean	equalsChv(byte[] chv1, byte[] chv2, int pos2) True if chv1[0..7] equals chv2[pos2..pos2+7].
protected int	getByte(byte[] buf, int pos) Reads one unsigned bytes from buf[pos].
protected int	getWord(byte[] buf, int pos) Reads a two-byte word from buf[pos..pos+1].
protected void	setWord(byte[] buf, int pos, int value) Writes a two-byte word into buf[pos..pos+1].

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MF

public static final int MF

See Also:

Constant Field Values

PERM_ALWAYS

public static final int PERM_ALWAYS

Constants for file access permissions

See Also:

Constant Field Values

PERM_CHV1

public static final int PERM_CHV1

See Also:

Constant Field Values

PERM_ADM

public static final int PERM_ADM

See Also:

Constant Field Values

PERM_NEVER

public static final int PERM_NEVER

See Also:

Constant Field Values

Constructor Detail

GSM11Impl

public GSM11Impl()

Method Detail

cmd

public byte[] cmd(byte[] apdu)

This corresponds to sending a command to the SIM. It returns an array of bytes as a response. The caller is expected to know the length of the valid data within the returned array (typically 0), and the position of the two status bytes that follow the data. Note that in this Java implementation, the returned array may be reused, so successive calls will overwrite the contents.

Parameters:

apdu - Bytes 1..4 determine the command and its parameters

Returns:

The response array (ignore the length).

getWord

protected int getWord(byte[] buf,
                      int pos)

Reads a two-byte word from buf[pos..pos+1].

getByte

protected int getByte(byte[] buf,
                      int pos)

Reads one unsigned bytes from buf[pos].

setWord

protected void setWord(byte[] buf,
                       int pos,
                       int value)

Writes a two-byte word into buf[pos..pos+1].

equalsChv

protected boolean equalsChv(byte[] chv1,
                            byte[] chv2,
                            int pos2)

True if chv1[0..7] equals chv2[pos2..pos2+7].