From d20f93a2c04f72daebd227d2df8b5e22e609e69f Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Mon, 24 Feb 2020 22:42:22 +0100 Subject: [PATCH] add MobileIdentity as separate class, add test Use fixed applet-project.mk to put Mobile Identity implementations in a separate class MobileIdentity.java. That allows trivially testing the MobileIdentity implementation outside of an actual SIM card environment: add a 'test' target to the Makefile and a Test.java class that runs some tests. --- sim-applet/Makefile | 10 +- .../org/osmocom/IMSIPseudo/IMSIPseudo.java | 150 ++--------------- .../osmocom/IMSIPseudo/MobileIdentity.java | 152 ++++++++++++++++++ .../src/org/osmocom/IMSIPseudo/Test.java | 44 +++++ 4 files changed, 216 insertions(+), 140 deletions(-) create mode 100644 sim-applet/src/org/osmocom/IMSIPseudo/MobileIdentity.java create mode 100644 sim-applet/src/org/osmocom/IMSIPseudo/Test.java diff --git a/sim-applet/Makefile b/sim-applet/Makefile index 0300b4e..740ffd8 100644 --- a/sim-applet/Makefile +++ b/sim-applet/Makefile @@ -6,7 +6,8 @@ PACKAGE_AID = 0xd0:0x70:0x02:0xCA:0x44:0x90:0x01 PACKAGE_NAME = org.osmocom.IMSIPseudo PACKAGE_VERSION = 1.0 -SOURCES = src/org/osmocom/IMSIPseudo/IMSIPseudo.java +SOURCES = src/org/osmocom/IMSIPseudo/MobileIdentity.java src/org/osmocom/IMSIPseudo/IMSIPseudo.java + CAP_FILE = build/javacard/org/osmocom/IMSIPseudo/javacard/IMSIPseudo.cap include ./applet-project.mk @@ -37,3 +38,10 @@ remove: --kid "$$KID1" delete: remove + +.PHONY: test +test: + mkdir -p ./test/classes + javac -target 1.1 -source 1.3 -classpath test/classes -g -d ./test/classes src/org/osmocom/IMSIPseudo/MobileIdentity.java + javac -target 1.1 -source 1.3 -classpath test/classes -g -d ./test/classes src/org/osmocom/IMSIPseudo/Test.java + java -classpath test/classes org.osmocom.IMSIPseudo.Test diff --git a/sim-applet/src/org/osmocom/IMSIPseudo/IMSIPseudo.java b/sim-applet/src/org/osmocom/IMSIPseudo/IMSIPseudo.java index 00b6720..fdaca60 100755 --- a/sim-applet/src/org/osmocom/IMSIPseudo/IMSIPseudo.java +++ b/sim-applet/src/org/osmocom/IMSIPseudo/IMSIPseudo.java @@ -1,6 +1,7 @@ /* 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.*; @@ -30,8 +31,6 @@ public class IMSIPseudo extends Applet implements ToolkitInterface, ToolkitConst 'd', 'i', 'g', 'i', 't'}; private final Object[] itemListChangeIMSI = {changeIMSI, enterIMSI, setDigit1, setDigit2}; - private static final byte MI_IMSI = 1; - private IMSIPseudo() { gsmFile = SIMSystem.getTheSIMView(); @@ -130,140 +129,6 @@ public class IMSIPseudo extends Applet implements ToolkitInterface, ToolkitConst showMsg(msg); } - /* Convert BCD-encoded digit into printable character - * \param[in] bcd A single BCD-encoded digit - * \returns single printable character - */ - private byte bcd2char(byte bcd) - { - if (bcd < 0xa) - return (byte)('0' + bcd); - else - return (byte)('A' + (bcd - 0xa)); - } - - private 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; - } - - /* 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 - */ - private 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; - } - - private byte mi2str(byte dst[], byte dst_ofs, byte dst_len, - byte mi[], boolean allow_hex) - { - /* 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)); - bcd2str(dst, dst_ofs, dst_len, mi, start_nibble, end_nibble, allow_hex); - return (byte)(end_nibble - start_nibble); - } - - private byte[] str2mi(byte str[], byte mi_type) - { - /* 1 byte of MI length. - * 1 nibble of mi_type. - * str.length nibbles of MI BCD. - * The first MI digit is in the high-nibble of the mi_type, so an odd amount of digits becomes - * (1 + str.length)/2 bytes; an even amount of digits has same amount of bytes with the last - * nibble unused (0xf0). */ - byte len = (byte)(1 + (byte)(1 + str.length)/2); - byte mi[] = new byte[1 + len]; - mi[0] = len; - - boolean odd_digits = ((str.length & 1) != 0); - mi_type = (byte)(mi_type & 0x07); - if (odd_digits) - mi_type |= 0x08; - mi[1] = (byte)((char2bcd(str[0]) << 4) + mi_type); - byte str_i = 1; - for (byte bcd_i = 1; bcd_i < len; bcd_i++) { - byte data = char2bcd(str[str_i]); - str_i++; - if (str_i < str.length) { - data |= char2bcd(str[str_i]) << 4; - str_i++; - } else - data |= 0xf0; - mi[1 + bcd_i] = data; - } - return mi; - } - private byte nibble2hex(byte nibble) { nibble = (byte)(nibble & 0xf); @@ -290,7 +155,7 @@ public class IMSIPseudo extends Applet implements ToolkitInterface, ToolkitConst try { byte IMSI[] = readIMSI(); - mi2str(msg, (byte)14, (byte)16, IMSI, false); + MobileIdentity.mi2str(msg, (byte)14, (byte)16, IMSI, false); showMsgAndWaitKey(msg); } catch (SIMViewException e) { showError(e.getReason()); @@ -333,8 +198,15 @@ public class IMSIPseudo extends Applet implements ToolkitInterface, ToolkitConst { byte[] msg = {'N', 'e', 'w', ' ', 'I', 'M', 'S', 'I', '?'}; byte imsi[] = prompt(msg, (short)0, (short)15); - byte mi[] = str2mi(imsi, MI_IMSI); - showMsgAndWaitKey(hexdump(mi)); + /* 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); + showMsgAndWaitKey(hexdump(mi)); + } catch (Exception e) { + byte err[] = {'E', 'R', 'R' }; + showMsgAndWaitKey(err); + } } private byte[] readIMSI() diff --git a/sim-applet/src/org/osmocom/IMSIPseudo/MobileIdentity.java b/sim-applet/src/org/osmocom/IMSIPseudo/MobileIdentity.java new file mode 100644 index 0000000..e363932 --- /dev/null +++ b/sim-applet/src/org/osmocom/IMSIPseudo/MobileIdentity.java @@ -0,0 +1,152 @@ +/* Copyright 2020 sysmocom s.f.m.c. GmbH + * SPDX-License-Identifier: Apache-2.0 */ +package org.osmocom.IMSIPseudo; + +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 dst[], byte dst_ofs, byte dst_len, + byte mi[], boolean allow_hex) + { + /* 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)); + bcd2str(dst, dst_ofs, dst_len, mi, start_nibble, end_nibble, allow_hex); + return (byte)(end_nibble - start_nibble); + } + + 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; + } +} diff --git a/sim-applet/src/org/osmocom/IMSIPseudo/Test.java b/sim-applet/src/org/osmocom/IMSIPseudo/Test.java new file mode 100644 index 0000000..3b37f26 --- /dev/null +++ b/sim-applet/src/org/osmocom/IMSIPseudo/Test.java @@ -0,0 +1,44 @@ +/* Copyright 2020 sysmocom s.f.m.c. GmbH + * SPDX-License-Identifier: Apache-2.0 */ +package org.osmocom.IMSIPseudo; +import org.osmocom.IMSIPseudo.*; + +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)); + } + + public static void main(String args[]){ + System.out.println(hexdumpStr(MobileIdentity.str2mi("123456".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("1234567".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("12345678".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("123456789".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("1234567890".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("12345678901".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("123456789012".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("1234567890123".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("12345678901234".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("123456789012345".getBytes(), (byte)1, (byte)9))); + System.out.println(hexdumpStr(MobileIdentity.str2mi("1234567890123456".getBytes(), (byte)1, (byte)9))); + } +}