imsi-change: import from imsi-pseudonymization

Patch-by: nhofmeyr, osmith
master
Oliver Smith 3 years ago
parent d102599fcf
commit d3d776e26c
  1. 3
      imsi-change/.gitignore
  2. 202
      imsi-change/LICENSE
  3. 71
      imsi-change/Makefile
  4. 26
      imsi-change/README.md
  5. 51
      imsi-change/applet-project.mk
  6. 82
      imsi-change/src/org/osmocom/IMSIChange/Bytes.java
  7. 176
      imsi-change/src/org/osmocom/IMSIChange/IMSIChange.java
  8. 152
      imsi-change/src/org/osmocom/IMSIChange/MobileIdentity.java
  9. 75
      imsi-change/src/org/osmocom/IMSIChange/Test.java

@ -0,0 +1,3 @@
build/
test/
.sim-keys

@ -0,0 +1,202 @@
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@ -0,0 +1,71 @@
SIMTOOLS_DIR = ../../sim-tools
APPLET_AID = 0xd0:0x70:0x02:0xca:0x44:0x90:0x01:0x01
APPLET_NAME = org.osmocom.IMSIChange.IMSIChange
PACKAGE_AID = 0xd0:0x70:0x02:0xCA:0x44:0x90:0x01
PACKAGE_NAME = org.osmocom.IMSIChange
PACKAGE_VERSION = 1.0
SOURCES = \
src/org/osmocom/IMSIChange/Bytes.java \
src/org/osmocom/IMSIChange/MobileIdentity.java \
src/org/osmocom/IMSIChange/IMSIChange.java \
$(NULL)
CAP_FILE = build/javacard/org/osmocom/IMSIChange/javacard/IMSIChange.cap
include ./applet-project.mk
.PHONY: flash
flash: classes
$(eval MODULE_AID := $(shell echo $(APPLET_AID) | sed 's/0x//g' | sed 's/\://g'))
$(eval INSTANCE_AID := $(shell echo $(APPLET_AID) | sed 's/0x//g' | sed 's/\://g'))
. $$PWD/.sim-keys && $(SIMTOOLS_DIR)/bin/shadysim \
--pcsc \
-l $(CAP_FILE) \
-i $(CAP_FILE) \
--enable-sim-toolkit \
--access-domain=00 \
--module-aid $(MODULE_AID) \
--instance-aid $(INSTANCE_AID) \
--nonvolatile-memory-required 0100 \
--volatile-memory-for-install 0100 \
--max-menu-entry-text 21 \
--max-menu-entries 01 \
--kic "$$KIC1" \
--kid "$$KID1"
.PHONY: remove
remove:
. $$PWD/.sim-keys && $(SIMTOOLS_DIR)/bin/shadysim \
--pcsc \
-d "$$(echo $(PACKAGE_AID) | sed 's/0x//g' | sed 's/\://g')" \
--kic "$$KIC1" \
--kid "$$KID1"
.PHONY: list
list:
. $$PWD/.sim-keys && $(SIMTOOLS_DIR)/bin/shadysim \
--pcsc \
--list-applets \
--kic "$$KIC1" \
--kid "$$KID1"
.PHONY: delete
delete: remove
.PHONY: reflash
reflash:
$(MAKE) remove
$(MAKE) flash
.PHONY: test
test:
mkdir -p ./test/classes
javac -target 1.1 -source 1.3 -classpath test/classes -g -d ./test/classes src/org/osmocom/IMSIChange/Bytes.java
javac -target 1.1 -source 1.3 -classpath test/classes -g -d ./test/classes src/org/osmocom/IMSIChange/MobileIdentity.java
javac -target 1.1 -source 1.3 -classpath test/classes -g -d ./test/classes src/org/osmocom/IMSIChange/Test.java
java -classpath test/classes org.osmocom.IMSIChange.Test
.PHONY: check
check: test

@ -0,0 +1,26 @@
# IMSI change SIM applet
Display and change the IMSI of the SIM. This is a standalone version of a debug
feature in the more complex IMSI Pseudonymization applet. To be used as example
code to build other applets.
### How to flash
```
$ cp .sim-keys.example .sim-keys
$ nvim .sim-keys # adjust KIC1, KID1
$ make flash
```
Before flashing a second time, remove the sim applet:
```
$ make remove
```
### Related
* [IMSI Pseudonymization](https://osmocom.org/projects/imsi-pseudo/wiki)
* [Shadysimply in Osmocom wiki](https://osmocom.org/projects/cellular-infrastructure/wiki/Shadysimpy)

@ -0,0 +1,51 @@
BUILD_DIR = ./build
BUILD_CLASSES_DIR = $(BUILD_DIR)/classes
BUILD_JAVACARD_DIR = $(BUILD_DIR)/javacard
JAVACARD_SDK_DIR ?= $(SIMTOOLS_DIR)/javacard
JAVACARD_EXPORT_DIR ?= $(JAVACARD_SDK_DIR)/api21_export_files
ifdef COMSPEC
CLASSPATH = $(JAVACARD_SDK_DIR)/lib/api21.jar;$(JAVACARD_SDK_DIR)/lib/sim.jar
else
CLASSPATH = $(JAVACARD_SDK_DIR)/lib/api21.jar:$(JAVACARD_SDK_DIR)/lib/sim.jar
endif
JFLAGS = -target 1.1 -source 1.3 -g -d $(BUILD_CLASSES_DIR) -classpath "$(BUILD_CLASSES_DIR):$(CLASSPATH)"
JAVA ?= java
JC ?= javac
.SUFFIXES: .java .class
.java.class:
@mkdir -p $(BUILD_CLASSES_DIR)
@mkdir -p $(BUILD_JAVACARD_DIR)
$(JC) $(JFLAGS) $*.java
.PHONY: jar
jar: classes
$(JAVA) -jar $(JAVACARD_SDK_DIR)/bin/converter.jar \
-d $(BUILD_JAVACARD_DIR) \
-classdir $(BUILD_CLASSES_DIR) \
-exportpath $(JAVACARD_EXPORT_DIR) \
-applet $(APPLET_AID) $(APPLET_NAME) \
$(PACKAGE_NAME) $(PACKAGE_AID) $(PACKAGE_VERSION)
default: jar
classes: $(SOURCES:.java=.class)
clean:
$(RM) -rf $(BUILD_DIR)
install:
$(eval CAP_FILE := $(shell find $(BUILD_JAVACARD_DIR) -name *.cap))
$(eval MODULE_AID := $(shell echo $(APPLET_AID) | sed 's/0x//g' | sed 's/\://g'))
$(eval INSTANCE_AID := $(shell echo $(APPLET_AID) | sed 's/0x//g' | sed 's/\://g'))
$(SIMTOOLS_DIR)/bin/shadysim \
$(SHADYSIM_OPTIONS) \
-l $(CAP_FILE) \
-i $(CAP_FILE) \
--enable-sim-toolkit \
--module-aid $(MODULE_AID) \
--instance-aid $(INSTANCE_AID) \
--nonvolatile-memory-required 0100 \
--volatile-memory-for-install 0100 \
--max-menu-entry-text 10 \
--max-menu-entries 01

@ -0,0 +1,82 @@
/* Copyright 2020 sysmocom s.f.m.c. GmbH
* SPDX-License-Identifier: Apache-2.0 */
package org.osmocom.IMSIChange;
public class Bytes {
public static byte nibble2hex(byte nibble)
{
nibble = (byte)(nibble & 0xf);
if (nibble < 0xa)
return (byte)('0' + nibble);
else
return (byte)('a' + nibble - 0xa);
}
public static byte[] hexdump(byte data[])
{
byte res[] = new byte[(byte)(data.length*2)];
for (byte i = 0; i < data.length; i++) {
res[(byte)(i*2)] = nibble2hex((byte)(data[i] >> 4));
res[(byte)(i*2 + 1)] = nibble2hex(data[i]);
}
return res;
}
public static boolean equals(byte a[], byte b[])
{
if (a.length != b.length)
return false;
for (short i = 0; i < (short)a.length; i++) {
if (a[i] != b[i])
return false;
}
return true;
}
public static boolean isDigit(byte digits[])
{
for (short i = 0; i < (short)digits.length; i++) {
if (digits[i] < '0' || digits[i] > '9')
return false;
}
return true;
}
public static byte[] toStr(byte byte_nr)
{
byte str[];
short nr = byte_nr;
byte d;
byte l = 0;
if (nr < 0) {
l = 1;
nr = (short)-nr;
}
if (nr > 99) {
l += 3;
d = 100;
}
else if (nr > 9) {
l += 2;
d = 10;
}
else {
str = new byte[1];
l += 1;
d = 1;
}
byte i = 0;
str = new byte[l];
if (byte_nr < 0)
str[i++] = '-';
while (d > 0) {
str[i++] = (byte)('0' + (nr / d));
nr %= d;
d /= 10;
}
return str;
}
}

@ -0,0 +1,176 @@
/* Copyright 2020 sysmocom s.f.m.c. GmbH
* SPDX-License-Identifier: Apache-2.0 */
package org.osmocom.IMSIChange;
import org.osmocom.IMSIChange.MobileIdentity;
import sim.access.*;
import sim.toolkit.*;
import javacard.framework.*;
public class IMSIChange 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;
/* Main menu */
private static final byte[] changeIMSI = {'C', 'h', 'a', 'n', 'g', 'e', ' ', 'I', 'M', 'S', 'I'};
private static final byte[] invalidIMSI = {'I', 'n', 'v', 'a', 'l', 'i', 'd', ' ', 'I', 'M', 'S', 'I'};
private static final byte[] noChange = {'N', 'o', ' ', 'c', 'h', 'a', 'n', 'g', 'e'};
private static final byte[] changed = {'I', 'M', 'S', 'I', ' ', 'c', 'h', 'a', 'n', 'g', 'e', 'd', '!'};
private IMSIChange() {
gsmFile = SIMSystem.getTheSIMView();
ToolkitRegistry reg = ToolkitRegistry.getEntry();
STKServicesMenuId = reg.initMenuEntry(changeIMSI, (short)0, (short)changeIMSI.length,
PRO_CMD_SELECT_ITEM, false, (byte)0, (short)0);
}
public static void install(byte[] bArray, short bOffset, byte bLength) {
IMSIChange applet = new IMSIChange();
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) {
byte prevIMSI_mi[] = readIMSI();
byte prevIMSI_str[] = MobileIdentity.mi2str(prevIMSI_mi);
promptIMSI(prevIMSI_str);
}
}
}
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;
}
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.
* 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 = {'E', '?', '?'};
msg[1] = (byte)('0' + code / 10);
msg[2] = (byte)('0' + code % 10);
showMsg(msg);
}
private void promptIMSI(byte prevIMSI_str[])
{
byte newIMSI_str[] = prevIMSI_str;
try {
newIMSI_str = prompt(changeIMSI, newIMSI_str, (short)0, (short)15);
} catch (Exception e) {
showError((short)40);
return;
}
if (newIMSI_str.length < 6 || newIMSI_str.length > 15
|| !Bytes.isDigit(newIMSI_str)) {
showMsg(invalidIMSI);
return;
}
if (Bytes.equals(newIMSI_str, prevIMSI_str)) {
showMsg(noChange);
return;
}
byte mi[];
try {
/* The IMSI file should be 9 bytes long, even if the IMSI is shorter */
mi = MobileIdentity.str2mi(newIMSI_str, MobileIdentity.MI_IMSI, (byte)9);
writeIMSI(mi);
showMsg(changed);
refreshIMSI();
} catch (Exception e) {
showError((short)42);
}
}
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[]) throws Exception
{
if (mi.length != 9)
throw new Exception();
gsmFile.select((short) SIMView.FID_DF_GSM);
gsmFile.select((short) SIMView.FID_EF_IMSI);
gsmFile.updateBinary((short)0, mi, (short)0, (short)mi.length);
}
/*
* - command qualifiers for REFRESH,
* ETSI TS 101 267 / 3GPP TS 11.14 chapter 12.6 "Command details":
* '00' =SIM Initialization and Full File Change Notification;
* '01' = File Change Notification;
* '02' = SIM Initialization and File Change Notification;
* '03' = SIM Initialization;
* '04' = SIM Reset;
* '05' to 'FF' = reserved values.
*/
public static final byte SIM_REFRESH_SIM_INIT_FULL_FILE_CHANGE = 0x00;
public static final byte SIM_REFRESH_FILE_CHANGE = 0x01;
public static final byte SIM_REFRESH_SIM_INIT_FILE_CHANGE = 0x02;
public static final byte SIM_REFRESH_SIM_INIT = 0x03;
public static final byte SIM_REFRESH_SIM_RESET = 0x04;
/* Run the Proactive SIM REFRESH command for the FID_EF_IMSI. */
private void refreshIMSI()
{
/* See ETSI TS 101 267 / 3GPP TS 11.14 section 6.4.7.1 "EF IMSI changing procedure":
* Valid qualifiers are SIM_REFRESH_SIM_INIT_FILE_CHANGE and SIM_REFRESH_SIM_INIT_FULL_FILE_CHANGE.
*/
ProactiveHandler proHdlr = ProactiveHandler.getTheHandler();
proHdlr.init((byte)PRO_CMD_REFRESH, SIM_REFRESH_SIM_INIT_FULL_FILE_CHANGE, DEV_ID_ME);
proHdlr.send();
}
}

@ -0,0 +1,152 @@
/* Copyright 2020 sysmocom s.f.m.c. GmbH
* SPDX-License-Identifier: Apache-2.0 */
package org.osmocom.IMSIChange;
public class MobileIdentity {
public static final byte MI_IMSI = 1;
/* Convert BCD-encoded digit into printable character
* \param[in] bcd A single BCD-encoded digit
* \returns single printable character
*/
public static byte bcd2char(byte bcd)
{
if (bcd < 0xa)
return (byte)('0' + bcd);
else
return (byte)('A' + (bcd - 0xa));
}
/* Convert BCD to string.
* The given nibble offsets are interpreted in BCD order, i.e. nibble 0 is bcd[0] & 0xf, nibble 1 is bcd[0] >> 4, nibble
* 3 is bcd[1] & 0xf, etc..
* \param[out] dst Output byte array.
* \param[in] dst_ofs Where to start writing in dst.
* \param[in] dst_len How many bytes are available at dst_ofs.
* \param[in] bcd Binary coded data buffer.
* \param[in] start_nibble Offset to start from, in nibbles.
* \param[in] end_nibble Offset to stop before, in nibbles.
* \param[in] allow_hex If false, return false if there are digits other than 0-9.
* \returns true on success, false otherwise
*/
public static boolean bcd2str(byte dst[], byte dst_ofs, byte dst_len,
byte bcd[], byte start_nibble, byte end_nibble, boolean allow_hex)
{
byte nibble_i;
byte dst_i = dst_ofs;
byte dst_end = (byte)(dst_ofs + dst_len);
boolean rc = true;
for (nibble_i = start_nibble; nibble_i < end_nibble && dst_i < dst_end; nibble_i++, dst_i++) {
byte nibble = bcd[(byte)nibble_i >> 1];
if ((nibble_i & 1) != 0)
nibble >>= 4;
nibble &= 0xf;
if (!allow_hex && nibble > 9)
rc = false;
dst[dst_i] = bcd2char(nibble);
}
return rc;
}
public static byte[] mi2str(byte mi[])
{
/* The IMSI byte array by example:
* 08 99 10 07 00 00 10 74 90
*
* This is encoded according to 3GPP TS 24.008 10.5.1.4 Mobile
* Identity, short the Mobile Identity IEI:
*
* 08 length for the following MI, in bytes.
* 9 = 0b1001
* 1 = odd nr of digits
* 001 = MI type = IMSI
* 9 first IMSI digit (BCD)
* 0 second digit
* 1 third
* ...
* 0 14th digit
* 9 15th and last digit
*
* If the IMSI had an even number of digits:
*
* 08 98 10 07 00 00 10 74 f0
*
* 08 length for the following MI, in bytes.
* 8 = 0b0001
* 0 = even nr of digits
* 001 = MI type = IMSI
* 9 first IMSI digit
* 0 second digit
* 1 third
* ...
* 0 14th and last digit
* f filler
*/
byte bytelen = mi[0];
byte mi_type = (byte)(mi[1] & 0xf);
boolean odd_nr_of_digits = ((mi_type & 0x08) != 0);
byte start_nibble = 2 + 1; // 2 to skip the bytelen, 1 to skip the mi_type
byte end_nibble = (byte)(2 + bytelen * 2 - (odd_nr_of_digits ? 0 : 1));
byte str[] = new byte[end_nibble - start_nibble];
bcd2str(str, (byte)0, (byte)str.length, mi, start_nibble, end_nibble, true);
return str;
}
public static byte char2bcd(byte c)
{
if (c >= '0' && c <= '9')
return (byte)(c - '0');
else if (c >= 'A' && c <= 'F')
return (byte)(0xa + (c - 'A'));
else if (c >= 'a' && c <= 'f')
return (byte)(0xa + (c - 'a'));
else
return 0;
}
public static byte[] str2mi(byte str[], byte mi_type, byte min_buflen)
{
boolean odd_digits = ((str.length & 1) != 0);
/* 1 nibble of mi_type.
* str.length nibbles of MI BCD.
*/
byte mi_nibbles = (byte)(1 + str.length);
byte mi_bytes = (byte)(mi_nibbles / 2 + ((mi_nibbles & 1) != 0? 1 : 0));
/* 1 byte of total MI length in bytes, plus the MI nibbles */
byte buflen = (byte)(1 + mi_bytes);
/* Fill up with 0xff to the requested buffer size */
if (buflen < min_buflen)
buflen = min_buflen;
byte buf[] = new byte[buflen];
for (byte i = 0; i < buf.length; i++)
buf[i] = (byte)0xff;
/* 1 byte of following MI length in bytes */
buf[0] = mi_bytes;
/* first MI byte: low nibble has the MI type and odd/even indicator bit,
* high nibble has the first BCD digit.
*/
mi_type = (byte)(mi_type & 0x07);
if (odd_digits)
mi_type |= 0x08;
buf[1] = (byte)((char2bcd(str[0]) << 4) + mi_type);
/* fill in the remaining MI nibbles */
byte str_i = 1;
for (byte mi_i = 1; mi_i < mi_bytes; mi_i++) {
byte data = char2bcd(str[str_i++]);
if (str_i < str.length)
data |= char2bcd(str[str_i++]) << 4;
else
data |= 0xf0;
buf[1 + mi_i] = data;
}
return buf;
}
}

@ -0,0 +1,75 @@
/* Copyright 2020 sysmocom s.f.m.c. GmbH
* SPDX-License-Identifier: Apache-2.0 */
package org.osmocom.IMSIChange;
import org.osmocom.IMSIChange.*;
public class Test {
private static byte nibble2hex(byte nibble)
{
nibble = (byte)(nibble & 0xf);
if (nibble < 0xa)
return (byte)('0' + nibble);
else
return (byte)('a' + nibble - 0xa);
}
private static byte[] hexdump(byte data[])
{
byte res[] = new byte[(byte)(data.length*2)];
for (byte i = 0; i < data.length; i++) {
res[(byte)(i*2)] = nibble2hex((byte)(data[i] >> 4));
res[(byte)(i*2 + 1)] = nibble2hex(data[i]);
}
return res;
}
private static String hexdumpStr(byte data[])
{
return new String(hexdump(data));
}
private static final String[] imsis = {
"123456",
"1234567",
"12345678",
"123456789",
"1234567890",
"12345678901",
"123456789012",
"1234567890123",
"12345678901234",
"123456789012345",
"1234567890123456",
};
private static void test_str2mi2str()
{
for (int i = 0; i < imsis.length; i++) {
byte str[] = imsis[i].getBytes();
byte mi[] = MobileIdentity.str2mi(str, MobileIdentity.MI_IMSI, (byte)9);
byte str_from_mi[] = MobileIdentity.mi2str(mi);
System.out.print("IMSI " + new String(str) + " --> MI " + hexdumpStr(mi) + " --> IMSI "
+ new String(str_from_mi));
if (Bytes.equals(str, str_from_mi))
System.out.println(" (ok)");
else
System.out.println(" ERROR!");
}
}
private static void test_toStr()
{
byte nr = -128;
while (true) {
System.out.println("" + nr + " = '" + new String(Bytes.toStr(nr)) + "'");
if (nr == 127)
break;
nr++;
}
}
public static void main(String args[]){
test_str2mi2str();
test_toStr();
}
}
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