sim-applet/src/org/osmocom/IMSIPseudo/IMSIPseudo.java - imsi-pseudo - Gitiles

 /* Copyright 2020 sysmocom s.f.m.c. GmbH
  * SPDX-License-Identifier: Apache-2.0 */
 package org.osmocom.IMSIPseudo;
 import org.osmocom.IMSIPseudo.MobileIdentity;

 import sim.access.*;
 import sim.toolkit.*;
 import javacard.framework.*;

 public class IMSIPseudo extends Applet implements ToolkitInterface, ToolkitConstants {
 	// DON'T DECLARE USELESS INSTANCE VARIABLES! They get saved to the EEPROM,
 	// which has a limited number of write cycles.

 	private byte STKServicesMenuId;
 	private SIMView gsmFile;
 	static byte[] LUCounter = new byte[] { '0', 'x', ' ', 'L', 'U' };

 	/* Main menu */
 	private static final byte[] title = new byte[] { 'I', 'M', 'S', 'I', ' ', 'P', 's', 'e', 'u', 'd', 'o', 'n', 'y', 'm',
 					   'i', 'z', 'a', 't', 'i', 'o', 'n'};
 	private static final byte[] showLU = new byte[] {'S', 'h', 'o', 'w', ' ', 'L', 'U', ' ', 'c', 'o', 'u', 'n', 't', 'e', 'r'};
 	private static final byte[] showIMSI = new byte[] {'S', 'h', 'o', 'w', ' ', 'I', 'M', 'S', 'I'};
 	private static final byte[] changeIMSI = new byte[] {'C', 'h', 'a', 'n', 'g', 'e', ' ', 'I', 'M', 'S', 'I', ' '};
 	private final Object[] itemListMain = {title, showLU, showIMSI, changeIMSI};

 	/* Change IMSI menu */
 	private static final byte[] enterIMSI = new byte[] {'E', 'n', 't', 'e', 'r', ' ', 'I', 'M', 'S', 'I' };
 	private static final byte[] setDigit1 = new byte[] {'S', 'e', 't', ' ', '1', ' ', 'a', 's', ' ', 'l', 'a', 's', 't', ' ',
 						  'd', 'i', 'g', 'i', 't'};
 	private static final byte[] setDigit2 = new byte[] {'S', 'e', 't', ' ', '2', ' ', 'a', 's', ' ', 'l', 'a', 's', 't', ' ',
 						  'd', 'i', 'g', 'i', 't'};
 	private final Object[] itemListChangeIMSI = {changeIMSI, enterIMSI, setDigit1, setDigit2};

 	private IMSIPseudo() {
 		gsmFile = SIMSystem.getTheSIMView();

 		/* Register menu and trigger on location updates */
 		ToolkitRegistry reg = ToolkitRegistry.getEntry();
 		STKServicesMenuId = reg.initMenuEntry(title, (short)0, (short)title.length, PRO_CMD_SELECT_ITEM, false,
 						 (byte)0, (short)0);
 		reg.setEvent(EVENT_EVENT_DOWNLOAD_LOCATION_STATUS);
 	}

 	public static void install(byte[] bArray, short bOffset, byte bLength) {
 		IMSIPseudo applet = new IMSIPseudo();
 		applet.register();
 	}

 	public void process(APDU arg0) throws ISOException {
 		if (selectingApplet())
 			return;
 	}

 	public void processToolkit(byte event) throws ToolkitException {
 		EnvelopeHandler envHdlr = EnvelopeHandler.getTheHandler();

 		if (event == EVENT_MENU_SELECTION) {
 			byte selectedItemId = envHdlr.getItemIdentifier();

 			if (selectedItemId == STKServicesMenuId) {
 				showMenu(itemListMain);
 				handleMenuResponseMain();
 			}
 		}

 		if (event == EVENT_EVENT_DOWNLOAD_LOCATION_STATUS) {
 			LUCounter[0]++;
 			showMsg(LUCounter);
 		}
 	}

 	private void showMenu(Object[] itemList) {
 		ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
 		proHdlr.init((byte) PRO_CMD_SELECT_ITEM,(byte)0,DEV_ID_ME);

 		for (byte i=(byte)0; i < itemList.length; i++) {
 			if (i == 0) {
 				/* Title */
 				proHdlr.appendTLV((byte)(TAG_ALPHA_IDENTIFIER | TAG_SET_CR), (byte[])itemList[i],
 						  (short)0, (short)((byte[])itemList[i]).length);

 			} else {
 				/* Menu entry */
 				proHdlr.appendTLV((byte)(TAG_ITEM | TAG_SET_CR), (byte)i, (byte[])itemList[i], (short)0,
 						  (short)((byte[])itemList[i]).length);
 			}
 		}
 		proHdlr.send();
 	}

 	private void showMsg(byte[] msg) {
 		ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
 		proHdlr.initDisplayText((byte)0, DCS_8_BIT_DATA, msg, (short)0, (short)(msg.length));
 		proHdlr.send();
 	}

 	private byte[] getResponse()
 	{
 		ProactiveResponseHandler rspHdlr = ProactiveResponseHandler.getTheHandler();
 		byte[] resp = new byte[rspHdlr.getTextStringLength()];
 		rspHdlr.copyTextString(resp, (short)0);
 		return resp;
 	}

 	/*
 	This was used to find out that the first byte of a text field seems to be 4.
 	private byte[] getResponseDBG()
 	{
 		ProactiveResponseHandler rspHdlr;
 		byte resp[];
 		byte strlen = -1;
 		rspHdlr = ProactiveResponseHandler.getTheHandler();

 		for (byte occurence = 1; occurence <= 3; occurence++) {
 			short len;
 			try {
 				if (rspHdlr.findTLV(TAG_TEXT_STRING, (byte)occurence) != TLV_NOT_FOUND) {
 					if ((len = rspHdlr.getValueLength()) > 1) {
 						len = 3;
 						resp = new byte[len];
 						rspHdlr.copyValue((short)0, resp, (short)0, (short)(len));
 						showMsg(resp);
 						showMsgAndWaitKey(Bytes.hexdump(resp));
 						return resp;
 					}
 				}
 			} catch (Exception e) {
 				showError((short)(30 + occurence));
 				return null;
 			}
 		}
 		showError((short)(39));
 		return null;
 	}
 	*/

 	private byte[] showMsgAndWaitKey(byte[] msg) {
 		ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
 		proHdlr.initGetInkey((byte)0, DCS_8_BIT_DATA, msg, (short)0, (short)(msg.length));
 		proHdlr.send();

 		return getResponse();
 	}

 	private byte[] prompt(byte[] msg, byte[] prefillVal, short minLen, short maxLen) {
 		/* if maxLen < 1, the applet crashes */
 		if (maxLen < 1)
 			maxLen = 1;

 		ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
 		proHdlr.initGetInput((byte)0, DCS_8_BIT_DATA, msg, (short)0, (short)(msg.length), minLen, maxLen);
 		if (prefillVal != null && prefillVal.length > 0) {
 			/* appendTLV() expects the first byte to be some header before the actual text.
 			 * At first I thought it was the value's length, but turned out to only work for lengths under 8...
 			 * In the end I reversed the value 4 from the first byte read by rspHdlr.copyValue() for
 			 * TAG_TEXT_STRING fields. As long as we write 4 into the first byte, things just work out,
 			 * apparently.
 			 * Fucking well could have said so in the API docs, too; oh the brain damage, oh the hours wasted.
 			 * This is the appendTLV() variant that writes one byte ahead of writing an array: */
 			proHdlr.appendTLV((byte)(TAG_DEFAULT_TEXT), (byte)4, prefillVal, (short)0,
 					  (short)(prefillVal.length));
 		}
 		proHdlr.send();

 		return getResponse();
 	}

 	private void showError(short code) {
 		byte[] msg = new byte[] {'E', '?', '?'};
 		msg[1] = (byte)('0' + code / 10);
 		msg[2] = (byte)('0' + code % 10);
 		showMsg(msg);
 	}


 	private void showIMSI() {
 		/* 3GPP TS 31.102 4.2.2: IMSI */
 		byte[] msg = {'C', 'u', 'r', 'r', 'e', 'n', 't', ' ', 'I', 'M', 'S', 'I', ':', ' ',
 			      ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' '};

 		try {
 			byte IMSI[] = readIMSI();
 			MobileIdentity.mi2str(msg, (byte)14, (byte)16, IMSI, false);
 			showMsgAndWaitKey(msg);
 		} catch (SIMViewException e) {
 			showError(e.getReason());
 		}
 	}

 	private void handleMenuResponseMain() {
 		ProactiveResponseHandler rspHdlr = ProactiveResponseHandler.getTheHandler();

 		switch (rspHdlr.getItemIdentifier()) {
 		case 1: /* Show LU counter */
 			showMsg(LUCounter);
 			break;
 		case 2: /* Show IMSI */
 			showIMSI();
 			break;
 		case 3: /* Change IMSI */
 			showMenu(itemListChangeIMSI);
 			handleMenuResponseChangeIMSI();
 			break;
 		}
 	}

 	private void handleMenuResponseChangeIMSI() {
 		ProactiveResponseHandler rspHdlr = ProactiveResponseHandler.getTheHandler();
 		switch (rspHdlr.getItemIdentifier()) {
 		case 1: /* enter IMSI */
 			promptIMSI();
 			break;
 		case 2: /* set last digit to 1 */
 			promptIMSI();
 			break;
 		case 3: /* set last digit to 2 */
 			promptIMSI();
 			break;
 		}
 	}

 	private void promptIMSI()
 	{
 		byte[] msg = {'N', 'e', 'w', ' ', 'I', 'M', 'S', 'I', '?'};
 		byte imsi[] = prompt(msg, (short)0, (short)15);
 		/* The IMSI file should be 9 bytes long, even if the IMSI is shorter */
 		byte mi[];
 		try {
 			mi = MobileIdentity.str2mi(imsi, MobileIdentity.MI_IMSI, (byte)9);
 			writeIMSI(mi);
 		} catch (Exception e) {
 			byte err[] = {'E', 'R', 'R' };
 			showMsgAndWaitKey(err);
 		}
 	}

 	private byte[] readIMSI()
 	{
 		gsmFile.select((short) SIMView.FID_DF_GSM);
 		gsmFile.select((short) SIMView.FID_EF_IMSI);
 		byte[] IMSI = new byte[9];
 		gsmFile.readBinary((short)0, IMSI, (short)0, (short)9);
 		return IMSI;
 	}

 	private void writeIMSI(byte mi[])
 	{
 		gsmFile.select((short) SIMView.FID_DF_GSM);
 		gsmFile.select((short) SIMView.FID_EF_IMSI);
 		gsmFile.updateBinary((short)0, mi, (short)0, (short)mi.length);
 	}
 }
	/* Copyright 2020 sysmocom s.f.m.c. GmbH
	* SPDX-License-Identifier: Apache-2.0 */
	package org.osmocom.IMSIPseudo;
	import org.osmocom.IMSIPseudo.MobileIdentity;

	import sim.access.*;
	import sim.toolkit.*;
	import javacard.framework.*;

	public class IMSIPseudo extends Applet implements ToolkitInterface, ToolkitConstants {
	// DON'T DECLARE USELESS INSTANCE VARIABLES! They get saved to the EEPROM,
	// which has a limited number of write cycles.

	private byte STKServicesMenuId;
	private SIMView gsmFile;
	static byte[] LUCounter = new byte[] { '0', 'x', ' ', 'L', 'U' };

	/* Main menu */
	private static final byte[] title = new byte[] { 'I', 'M', 'S', 'I', ' ', 'P', 's', 'e', 'u', 'd', 'o', 'n', 'y', 'm',
	'i', 'z', 'a', 't', 'i', 'o', 'n'};
	private static final byte[] showLU = new byte[] {'S', 'h', 'o', 'w', ' ', 'L', 'U', ' ', 'c', 'o', 'u', 'n', 't', 'e', 'r'};
	private static final byte[] showIMSI = new byte[] {'S', 'h', 'o', 'w', ' ', 'I', 'M', 'S', 'I'};
	private static final byte[] changeIMSI = new byte[] {'C', 'h', 'a', 'n', 'g', 'e', ' ', 'I', 'M', 'S', 'I', ' '};
	private final Object[] itemListMain = {title, showLU, showIMSI, changeIMSI};

	/* Change IMSI menu */
	private static final byte[] enterIMSI = new byte[] {'E', 'n', 't', 'e', 'r', ' ', 'I', 'M', 'S', 'I' };
	private static final byte[] setDigit1 = new byte[] {'S', 'e', 't', ' ', '1', ' ', 'a', 's', ' ', 'l', 'a', 's', 't', ' ',
	'd', 'i', 'g', 'i', 't'};
	private static final byte[] setDigit2 = new byte[] {'S', 'e', 't', ' ', '2', ' ', 'a', 's', ' ', 'l', 'a', 's', 't', ' ',
	'd', 'i', 'g', 'i', 't'};
	private final Object[] itemListChangeIMSI = {changeIMSI, enterIMSI, setDigit1, setDigit2};

	private IMSIPseudo() {
	gsmFile = SIMSystem.getTheSIMView();

	/* Register menu and trigger on location updates */
	ToolkitRegistry reg = ToolkitRegistry.getEntry();
	STKServicesMenuId = reg.initMenuEntry(title, (short)0, (short)title.length, PRO_CMD_SELECT_ITEM, false,
	(byte)0, (short)0);
	reg.setEvent(EVENT_EVENT_DOWNLOAD_LOCATION_STATUS);
	}

	public static void install(byte[] bArray, short bOffset, byte bLength) {
	IMSIPseudo applet = new IMSIPseudo();
	applet.register();
	}

	public void process(APDU arg0) throws ISOException {
	if (selectingApplet())
	return;
	}

	public void processToolkit(byte event) throws ToolkitException {
	EnvelopeHandler envHdlr = EnvelopeHandler.getTheHandler();

	if (event == EVENT_MENU_SELECTION) {
	byte selectedItemId = envHdlr.getItemIdentifier();

	if (selectedItemId == STKServicesMenuId) {
	showMenu(itemListMain);
	handleMenuResponseMain();
	}
	}

	if (event == EVENT_EVENT_DOWNLOAD_LOCATION_STATUS) {
	LUCounter[0]++;
	showMsg(LUCounter);
	}
	}

	private void showMenu(Object[] itemList) {
	ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
	proHdlr.init((byte) PRO_CMD_SELECT_ITEM,(byte)0,DEV_ID_ME);

	for (byte i=(byte)0; i < itemList.length; i++) {
	if (i == 0) {
	/* Title */
	proHdlr.appendTLV((byte)(TAG_ALPHA_IDENTIFIER \| TAG_SET_CR), (byte[])itemList[i],
	(short)0, (short)((byte[])itemList[i]).length);

	} else {
	/* Menu entry */
	proHdlr.appendTLV((byte)(TAG_ITEM \| TAG_SET_CR), (byte)i, (byte[])itemList[i], (short)0,
	(short)((byte[])itemList[i]).length);
	}
	}
	proHdlr.send();
	}

	private void showMsg(byte[] msg) {
	ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
	proHdlr.initDisplayText((byte)0, DCS_8_BIT_DATA, msg, (short)0, (short)(msg.length));
	proHdlr.send();
	}

	private byte[] getResponse()
	{
	ProactiveResponseHandler rspHdlr = ProactiveResponseHandler.getTheHandler();
	byte[] resp = new byte[rspHdlr.getTextStringLength()];
	rspHdlr.copyTextString(resp, (short)0);
	return resp;
	}

	/*
	This was used to find out that the first byte of a text field seems to be 4.
	private byte[] getResponseDBG()
	{
	ProactiveResponseHandler rspHdlr;
	byte resp[];
	byte strlen = -1;
	rspHdlr = ProactiveResponseHandler.getTheHandler();

	for (byte occurence = 1; occurence <= 3; occurence++) {
	short len;
	try {
	if (rspHdlr.findTLV(TAG_TEXT_STRING, (byte)occurence) != TLV_NOT_FOUND) {
	if ((len = rspHdlr.getValueLength()) > 1) {
	len = 3;
	resp = new byte[len];
	rspHdlr.copyValue((short)0, resp, (short)0, (short)(len));
	showMsg(resp);
	showMsgAndWaitKey(Bytes.hexdump(resp));
	return resp;
	}
	}
	} catch (Exception e) {
	showError((short)(30 + occurence));
	return null;
	}
	}
	showError((short)(39));
	return null;
	}
	*/

	private byte[] showMsgAndWaitKey(byte[] msg) {
	ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
	proHdlr.initGetInkey((byte)0, DCS_8_BIT_DATA, msg, (short)0, (short)(msg.length));
	proHdlr.send();

	return getResponse();
	}

	private byte[] prompt(byte[] msg, byte[] prefillVal, short minLen, short maxLen) {
	/* if maxLen < 1, the applet crashes */
	if (maxLen < 1)
	maxLen = 1;

	ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
	proHdlr.initGetInput((byte)0, DCS_8_BIT_DATA, msg, (short)0, (short)(msg.length), minLen, maxLen);
	if (prefillVal != null && prefillVal.length > 0) {
	/* appendTLV() expects the first byte to be some header before the actual text.
	* At first I thought it was the value's length, but turned out to only work for lengths under 8...
	* In the end I reversed the value 4 from the first byte read by rspHdlr.copyValue() for
	* TAG_TEXT_STRING fields. As long as we write 4 into the first byte, things just work out,
	* apparently.
	* Fucking well could have said so in the API docs, too; oh the brain damage, oh the hours wasted.
	* This is the appendTLV() variant that writes one byte ahead of writing an array: */
	proHdlr.appendTLV((byte)(TAG_DEFAULT_TEXT), (byte)4, prefillVal, (short)0,
	(short)(prefillVal.length));
	}
	proHdlr.send();

	return getResponse();
	}

	private void showError(short code) {
	byte[] msg = new byte[] {'E', '?', '?'};
	msg[1] = (byte)('0' + code / 10);
	msg[2] = (byte)('0' + code % 10);
	showMsg(msg);
	}


	private void showIMSI() {
	/* 3GPP TS 31.102 4.2.2: IMSI */
	byte[] msg = {'C', 'u', 'r', 'r', 'e', 'n', 't', ' ', 'I', 'M', 'S', 'I', ':', ' ',
	' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' '};

	try {
	byte IMSI[] = readIMSI();
	MobileIdentity.mi2str(msg, (byte)14, (byte)16, IMSI, false);
	showMsgAndWaitKey(msg);
	} catch (SIMViewException e) {
	showError(e.getReason());
	}
	}

	private void handleMenuResponseMain() {
	ProactiveResponseHandler rspHdlr = ProactiveResponseHandler.getTheHandler();

	switch (rspHdlr.getItemIdentifier()) {
	case 1: /* Show LU counter */
	showMsg(LUCounter);
	break;
	case 2: /* Show IMSI */
	showIMSI();
	break;
	case 3: /* Change IMSI */
	showMenu(itemListChangeIMSI);
	handleMenuResponseChangeIMSI();
	break;
	}
	}

	private void handleMenuResponseChangeIMSI() {
	ProactiveResponseHandler rspHdlr = ProactiveResponseHandler.getTheHandler();
	switch (rspHdlr.getItemIdentifier()) {
	case 1: /* enter IMSI */
	promptIMSI();
	break;
	case 2: /* set last digit to 1 */
	promptIMSI();
	break;
	case 3: /* set last digit to 2 */
	promptIMSI();
	break;
	}
	}

	private void promptIMSI()
	{
	byte[] msg = {'N', 'e', 'w', ' ', 'I', 'M', 'S', 'I', '?'};
	byte imsi[] = prompt(msg, (short)0, (short)15);
	/* The IMSI file should be 9 bytes long, even if the IMSI is shorter */
	byte mi[];
	try {
	mi = MobileIdentity.str2mi(imsi, MobileIdentity.MI_IMSI, (byte)9);
	writeIMSI(mi);
	} catch (Exception e) {
	byte err[] = {'E', 'R', 'R' };
	showMsgAndWaitKey(err);
	}
	}

	private byte[] readIMSI()
	{
	gsmFile.select((short) SIMView.FID_DF_GSM);
	gsmFile.select((short) SIMView.FID_EF_IMSI);
	byte[] IMSI = new byte[9];
	gsmFile.readBinary((short)0, IMSI, (short)0, (short)9);
	return IMSI;
	}

	private void writeIMSI(byte mi[])
	{
	gsmFile.select((short) SIMView.FID_DF_GSM);
	gsmFile.select((short) SIMView.FID_EF_IMSI);
	gsmFile.updateBinary((short)0, mi, (short)0, (short)mi.length);
	}
	}