proxmark3/armsrc/mifaresim.c
pwpiwi 6e49717b5e fix hf mf sim (issue #412) (#419)
* move to separate files mifaresim.[ch]
* check CRC of commands
* don't execute commands without successfull authentication
* ensure correct timing of REQA, WUPA, ANTICOL and SELECT responses
* trace reader commands immediately, only fix start time after tag response. Decreases time to be ready for next reader command.
* remove iso14443-4 remnants
* trace raw reader commands instead of decrypted ones
* some refactoring

* fix hf mf sim
* timing: decrease time to get ready for new reader commands
2017-10-20 17:55:13 +02:00

621 lines
24 KiB
C

//-----------------------------------------------------------------------------
// Merlok - June 2011, 2012
// Gerhard de Koning Gans - May 2008
// Hagen Fritsch - June 2010
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Mifare Classic Card Simulation
//-----------------------------------------------------------------------------
#include "mifaresim.h"
#include "iso14443a.h"
#include "iso14443crc.h"
#include "crapto1/crapto1.h"
#include "BigBuf.h"
#include "string.h"
#include "mifareutil.h"
#include "fpgaloader.h"
#include "proxmark3.h"
#include "usb_cdc.h"
#include "cmd.h"
#include "protocols.h"
#include "apps.h"
//mifare emulator states
#define MFEMUL_NOFIELD 0
#define MFEMUL_IDLE 1
#define MFEMUL_SELECT1 2
#define MFEMUL_SELECT2 3
#define MFEMUL_SELECT3 4
#define MFEMUL_AUTH1 5
#define MFEMUL_AUTH2 6
#define MFEMUL_WORK 7
#define MFEMUL_WRITEBL2 8
#define MFEMUL_INTREG_INC 9
#define MFEMUL_INTREG_DEC 10
#define MFEMUL_INTREG_REST 11
#define MFEMUL_HALTED 12
#define cardSTATE_TO_IDLE() { cardSTATE = MFEMUL_IDLE; LED_B_OFF(); LED_C_OFF(); }
static void MifareSimInit(uint8_t flags, uint8_t *datain, tag_response_info_t **responses, uint32_t *cuid, uint8_t *uid_len) {
#define TAG_RESPONSE_COUNT 5 // number of precompiled responses
static uint8_t rATQA[] = {0x04, 0x00}; // indicate Mifare classic 1k 4Byte UID
static uint8_t rUIDBCC1[] = {0x00, 0x00, 0x00, 0x00, 0x00}; // UID 1st cascade level
static uint8_t rUIDBCC2[] = {0x00, 0x00, 0x00, 0x00, 0x00}; // UID 2nd cascade level
static uint8_t rSAKfinal[]= {0x08, 0xb6, 0xdd}; // mifare 1k indicated
static uint8_t rSAK1[] = {0x04, 0xda, 0x17}; // indicate UID not finished
*uid_len = 4;
// UID can be set from emulator memory or incoming data and can be 4 or 7 bytes long
if (flags & FLAG_4B_UID_IN_DATA) { // get UID from datain
memcpy(rUIDBCC1, datain, 4);
} else if (flags & FLAG_7B_UID_IN_DATA) {
rUIDBCC1[0] = 0x88;
memcpy(rUIDBCC1+1, datain, 3);
memcpy(rUIDBCC2, datain+3, 4);
*uid_len = 7;
} else {
uint8_t probable_atqa;
emlGetMemBt(&probable_atqa, 7, 1); // get UID from emul memory - weak guess at length
if (probable_atqa == 0x00) { // ---------- 4BUID
emlGetMemBt(rUIDBCC1, 0, 4);
} else { // ---------- 7BUID
rUIDBCC1[0] = 0x88;
emlGetMemBt(rUIDBCC1+1, 0, 3);
emlGetMemBt(rUIDBCC2, 3, 4);
*uid_len = 7;
}
}
switch (*uid_len) {
case 4:
*cuid = bytes_to_num(rUIDBCC1, 4);
rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
if (MF_DBGLEVEL >= 2) {
Dbprintf("4B UID: %02x%02x%02x%02x",
rUIDBCC1[0], rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3] );
}
break;
case 7:
rATQA[0] |= 0x40;
*cuid = bytes_to_num(rUIDBCC2, 4);
rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
if (MF_DBGLEVEL >= 2) {
Dbprintf("7B UID: %02x %02x %02x %02x %02x %02x %02x",
rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3], rUIDBCC2[0], rUIDBCC2[1], rUIDBCC2[2], rUIDBCC2[3] );
}
break;
default:
break;
}
static tag_response_info_t responses_init[TAG_RESPONSE_COUNT] = {
{ .response = rATQA, .response_n = sizeof(rATQA) }, // Answer to request - respond with card type
{ .response = rUIDBCC1, .response_n = sizeof(rUIDBCC1) }, // Anticollision cascade1 - respond with first part of uid
{ .response = rUIDBCC2, .response_n = sizeof(rUIDBCC2) }, // Anticollision cascade2 - respond with 2nd part of uid
{ .response = rSAKfinal, .response_n = sizeof(rSAKfinal) }, // Acknowledge select - last cascade
{ .response = rSAK1, .response_n = sizeof(rSAK1) } // Acknowledge select - previous cascades
};
// Prepare ("precompile") the responses of the anticollision phase. There will be not enough time to do this at the moment the reader sends its REQA or SELECT
// There are 7 predefined responses with a total of 18 bytes data to transmit. Coded responses need one byte per bit to transfer (data, parity, start, stop, correction)
// 18 * 8 data bits, 18 * 1 parity bits, 5 start bits, 5 stop bits, 5 correction bits -> need 177 bytes buffer
#define ALLOCATED_TAG_MODULATION_BUFFER_SIZE 177 // number of bytes required for precompiled responses
uint8_t *free_buffer_pointer = BigBuf_malloc(ALLOCATED_TAG_MODULATION_BUFFER_SIZE);
size_t free_buffer_size = ALLOCATED_TAG_MODULATION_BUFFER_SIZE;
for (size_t i = 0; i < TAG_RESPONSE_COUNT; i++) {
prepare_allocated_tag_modulation(&responses_init[i], &free_buffer_pointer, &free_buffer_size);
}
*responses = responses_init;
// indices into responses array:
#define ATQA 0
#define UIDBCC1 1
#define UIDBCC2 2
#define SAKfinal 3
#define SAK1 4
}
static bool HasValidCRC(uint8_t *receivedCmd, uint16_t receivedCmd_len) {
uint8_t CRC_byte_1, CRC_byte_2;
ComputeCrc14443(CRC_14443_A, receivedCmd, receivedCmd_len-2, &CRC_byte_1, &CRC_byte_2);
return (receivedCmd[receivedCmd_len-2] == CRC_byte_1 && receivedCmd[receivedCmd_len-1] == CRC_byte_2);
}
/**
*MIFARE 1K simulate.
*
*@param flags :
* FLAG_INTERACTIVE - In interactive mode, we are expected to finish the operation with an ACK
* FLAG_4B_UID_IN_DATA - means that there is a 4-byte UID in the data-section, we're expected to use that
* FLAG_7B_UID_IN_DATA - means that there is a 7-byte UID in the data-section, we're expected to use that
* FLAG_10B_UID_IN_DATA - use 10-byte UID in the data-section not finished
* FLAG_NR_AR_ATTACK - means we should collect NR_AR responses for bruteforcing later
* FLAG_RANDOM_NONCE - means we should generate some pseudo-random nonce data (only allows moebius attack)
*@param exitAfterNReads, exit simulation after n blocks have been read, 0 is infinite ...
* (unless reader attack mode enabled then it runs util it gets enough nonces to recover all keys attmpted)
*/
void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain)
{
tag_response_info_t *responses;
uint8_t uid_len = 4;
uint32_t cuid = 0;
uint8_t cardWRBL = 0;
uint8_t cardAUTHSC = 0;
uint8_t cardAUTHKEY = 0xff; // no authentication
uint32_t cardRr = 0;
//uint32_t rn_enc = 0;
uint32_t ans = 0;
uint32_t cardINTREG = 0;
uint8_t cardINTBLOCK = 0;
struct Crypto1State mpcs = {0, 0};
struct Crypto1State *pcs;
pcs = &mpcs;
uint32_t numReads = 0;//Counts numer of times reader reads a block
uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE];
uint8_t receivedCmd_dec[MAX_MIFARE_FRAME_SIZE];
uint8_t receivedCmd_par[MAX_MIFARE_PARITY_SIZE];
uint16_t receivedCmd_len;
uint8_t response[MAX_MIFARE_FRAME_SIZE];
uint8_t response_par[MAX_MIFARE_PARITY_SIZE];
uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04};
uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
//Here, we collect UID,sector,keytype,NT,AR,NR,NT2,AR2,NR2
// This will be used in the reader-only attack.
//allow collecting up to 7 sets of nonces to allow recovery of up to 7 keys
#define ATTACK_KEY_COUNT 7 // keep same as define in cmdhfmf.c -> readerAttack() (Cannot be more than 7)
nonces_t ar_nr_resp[ATTACK_KEY_COUNT*2]; //*2 for 2 separate attack types (nml, moebius) 36 * 7 * 2 bytes = 504 bytes
memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp));
uint8_t ar_nr_collected[ATTACK_KEY_COUNT*2]; //*2 for 2nd attack type (moebius)
memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected));
uint8_t nonce1_count = 0;
uint8_t nonce2_count = 0;
uint8_t moebius_n_count = 0;
bool gettingMoebius = false;
uint8_t mM = 0; //moebius_modifier for collection storage
// Authenticate response - nonce
uint32_t nonce;
if (flags & FLAG_RANDOM_NONCE) {
nonce = prand();
} else {
nonce = bytes_to_num(rAUTH_NT, 4);
}
// free eventually allocated BigBuf memory but keep Emulator Memory
BigBuf_free_keep_EM();
MifareSimInit(flags, datain, &responses, &cuid, &uid_len);
// We need to listen to the high-frequency, peak-detected path.
iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
// clear trace
clear_trace();
set_tracing(true);
ResetSspClk();
bool finished = false;
bool button_pushed = BUTTON_PRESS();
int cardSTATE = MFEMUL_NOFIELD;
while (!button_pushed && !finished && !usb_poll_validate_length()) {
WDT_HIT();
// find reader field
if (cardSTATE == MFEMUL_NOFIELD) {
int vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
if (vHf > MF_MINFIELDV) {
LED_A_ON();
cardSTATE_TO_IDLE();
}
button_pushed = BUTTON_PRESS();
continue;
}
//Now, get data
int res = EmGetCmd(receivedCmd, &receivedCmd_len, receivedCmd_par);
if (res == 2) { //Field is off!
LEDsoff();
cardSTATE = MFEMUL_NOFIELD;
continue;
} else if (res == 1) { // button pressed
button_pushed = true;
break;
}
// WUPA in HALTED state or REQA or WUPA in any other state
if (receivedCmd_len == 1 && ((receivedCmd[0] == ISO14443A_CMD_REQA && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == ISO14443A_CMD_WUPA)) {
EmSendPrecompiledCmd(&responses[ATQA], (receivedCmd[0] == ISO14443A_CMD_WUPA));
// init crypto block
crypto1_destroy(pcs);
cardAUTHKEY = 0xff;
if (flags & FLAG_RANDOM_NONCE) {
nonce = prand();
}
LED_B_OFF();
LED_C_OFF();
cardSTATE = MFEMUL_SELECT1;
continue;
}
switch (cardSTATE) {
case MFEMUL_NOFIELD:
case MFEMUL_HALTED:
case MFEMUL_IDLE:{
break;
}
case MFEMUL_SELECT1:{
// select all - 0x93 0x20
if (receivedCmd_len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x20)) {
if (MF_DBGLEVEL >= 4) Dbprintf("SELECT ALL CL1 received");
EmSendPrecompiledCmd(&responses[UIDBCC1], false);
break;
}
// select card - 0x93 0x70 ...
if (receivedCmd_len == 9 &&
(receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], responses[UIDBCC1].response, 4) == 0)) {
if (MF_DBGLEVEL >= 4) Dbprintf("SELECT CL1 %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]);
if (uid_len == 4) {
EmSendPrecompiledCmd(&responses[SAKfinal], false);
LED_B_ON();
cardSTATE = MFEMUL_WORK;
break;
} else if (uid_len == 7) {
EmSendPrecompiledCmd(&responses[SAK1], false);
cardSTATE = MFEMUL_SELECT2;
break;
}
}
cardSTATE_TO_IDLE();
break;
}
case MFEMUL_SELECT2:{
// select all cl2 - 0x95 0x20
if (receivedCmd_len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x20)) {
if (MF_DBGLEVEL >= 4) Dbprintf("SELECT ALL CL2 received");
EmSendPrecompiledCmd(&responses[UIDBCC2], false);
break;
}
// select cl2 card - 0x95 0x70 xxxxxxxxxxxx
if (receivedCmd_len == 9 &&
(receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], responses[UIDBCC2].response, 4) == 0)) {
if (uid_len == 7) {
if (MF_DBGLEVEL >= 4) Dbprintf("SELECT CL2 %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]);
EmSendPrecompiledCmd(&responses[SAKfinal], false);
LED_B_ON();
cardSTATE = MFEMUL_WORK;
break;
}
}
cardSTATE_TO_IDLE();
break;
}
case MFEMUL_WORK:{
if (receivedCmd_len != 4) { // all commands must have exactly 4 bytes
break;
}
bool encrypted_data = (cardAUTHKEY != 0xFF) ;
if (encrypted_data) {
// decrypt seqence
mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, receivedCmd_dec);
} else {
memcpy(receivedCmd_dec, receivedCmd, receivedCmd_len);
}
if (!HasValidCRC(receivedCmd_dec, receivedCmd_len)) { // all commands must have a valid CRC
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
break;
}
if (receivedCmd_dec[0] == MIFARE_AUTH_KEYA || receivedCmd_dec[0] == MIFARE_AUTH_KEYB) {
// if authenticating to a block that shouldn't exist - as long as we are not doing the reader attack
if (receivedCmd_dec[1] >= 16 * 4 && !(flags & FLAG_NR_AR_ATTACK)) {
//is this the correct response to an auth on a out of range block? marshmellow
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on out of range block: %d (0x%02x), nacking",receivedCmd_dec[0],receivedCmd_dec[1],receivedCmd_dec[1]);
break;
}
cardAUTHSC = receivedCmd_dec[1] / 4; // received block num
cardAUTHKEY = receivedCmd_dec[0] & 0x01;
crypto1_destroy(pcs);//Added by martin
crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
if (!encrypted_data) { // first authentication
if (MF_DBGLEVEL >= 4) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd_dec[1], receivedCmd_dec[1], cardAUTHKEY);
crypto1_word(pcs, cuid ^ nonce, 0);//Update crypto state
num_to_bytes(nonce, 4, rAUTH_AT); // Send nonce
} else { // nested authentication
if (MF_DBGLEVEL >= 4) Dbprintf("Reader doing nested authentication for block %d (0x%02x) with key %d", receivedCmd_dec[1], receivedCmd_dec[1], cardAUTHKEY);
ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
num_to_bytes(ans, 4, rAUTH_AT);
}
EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
cardSTATE = MFEMUL_AUTH1;
break;
}
if (!encrypted_data) { // all other commands must be encrypted (authenticated)
break;
}
if(receivedCmd_dec[0] == ISO14443A_CMD_READBLOCK
|| receivedCmd_dec[0] == ISO14443A_CMD_WRITEBLOCK
|| receivedCmd_dec[0] == MIFARE_CMD_INC
|| receivedCmd_dec[0] == MIFARE_CMD_DEC
|| receivedCmd_dec[0] == MIFARE_CMD_RESTORE
|| receivedCmd_dec[0] == MIFARE_CMD_TRANSFER) {
if (receivedCmd_dec[1] >= 16 * 4) {
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on out of range block: %d (0x%02x), nacking",receivedCmd_dec[0],receivedCmd_dec[1],receivedCmd_dec[1]);
break;
}
if (receivedCmd_dec[1] / 4 != cardAUTHSC) {
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd_dec[0],receivedCmd_dec[1],cardAUTHSC);
break;
}
}
if (receivedCmd_dec[0] == ISO14443A_CMD_READBLOCK) {
if (MF_DBGLEVEL >= 4) {
Dbprintf("Reader reading block %d (0x%02x)",receivedCmd_dec[1],receivedCmd_dec[1]);
}
emlGetMem(response, receivedCmd_dec[1], 1);
AppendCrc14443a(response, 16);
mf_crypto1_encrypt(pcs, response, 18, response_par);
EmSendCmdPar(response, 18, response_par);
numReads++;
if(exitAfterNReads > 0 && numReads == exitAfterNReads) {
Dbprintf("%d reads done, exiting", numReads);
finished = true;
}
break;
}
if (receivedCmd_dec[0] == ISO14443A_CMD_WRITEBLOCK) {
if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0xA0 write block %d (%02x)",receivedCmd_dec[1],receivedCmd_dec[1]);
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
cardWRBL = receivedCmd_dec[1];
cardSTATE = MFEMUL_WRITEBL2;
break;
}
if (receivedCmd_dec[0] == MIFARE_CMD_INC || receivedCmd_dec[0] == MIFARE_CMD_DEC || receivedCmd_dec[0] == MIFARE_CMD_RESTORE) {
if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x inc(0xC1)/dec(0xC0)/restore(0xC2) block %d (%02x)",receivedCmd_dec[0],receivedCmd_dec[1],receivedCmd_dec[1]);
if (emlCheckValBl(receivedCmd_dec[1])) {
if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate on block, but emlCheckValBl failed, nacking");
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
break;
}
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
cardWRBL = receivedCmd_dec[1];
if (receivedCmd_dec[0] == MIFARE_CMD_INC)
cardSTATE = MFEMUL_INTREG_INC;
if (receivedCmd_dec[0] == MIFARE_CMD_DEC)
cardSTATE = MFEMUL_INTREG_DEC;
if (receivedCmd_dec[0] == MIFARE_CMD_RESTORE)
cardSTATE = MFEMUL_INTREG_REST;
break;
}
if (receivedCmd_dec[0] == MIFARE_CMD_TRANSFER) {
if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x transfer block %d (%02x)",receivedCmd_dec[0],receivedCmd_dec[1],receivedCmd_dec[1]);
if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd_dec[1]))
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
else
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
break;
}
// halt
if (receivedCmd_dec[0] == ISO14443A_CMD_HALT && receivedCmd_dec[1] == 0x00) {
if (MF_DBGLEVEL >= 4) Dbprintf("--> HALTED.");
LED_B_OFF();
LED_C_OFF();
cardSTATE = MFEMUL_HALTED;
break;
}
// command not allowed
if (MF_DBGLEVEL >= 4) Dbprintf("Received command not allowed, nacking");
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
break;
}
case MFEMUL_AUTH1:{
if (receivedCmd_len != 8) {
cardSTATE_TO_IDLE();
break;
}
uint32_t nr = bytes_to_num(receivedCmd, 4);
uint32_t ar = bytes_to_num(&receivedCmd[4], 4);
// Collect AR/NR per keytype & sector
if(flags & FLAG_NR_AR_ATTACK) {
for (uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
if ( ar_nr_collected[i+mM]==0 || ((cardAUTHSC == ar_nr_resp[i+mM].sector) && (cardAUTHKEY == ar_nr_resp[i+mM].keytype) && (ar_nr_collected[i+mM] > 0)) ) {
// if first auth for sector, or matches sector and keytype of previous auth
if (ar_nr_collected[i+mM] < 2) {
// if we haven't already collected 2 nonces for this sector
if (ar_nr_resp[ar_nr_collected[i+mM]].ar != ar) {
// Avoid duplicates... probably not necessary, ar should vary.
if (ar_nr_collected[i+mM]==0) {
// first nonce collect
ar_nr_resp[i+mM].cuid = cuid;
ar_nr_resp[i+mM].sector = cardAUTHSC;
ar_nr_resp[i+mM].keytype = cardAUTHKEY;
ar_nr_resp[i+mM].nonce = nonce;
ar_nr_resp[i+mM].nr = nr;
ar_nr_resp[i+mM].ar = ar;
nonce1_count++;
// add this nonce to first moebius nonce
ar_nr_resp[i+ATTACK_KEY_COUNT].cuid = cuid;
ar_nr_resp[i+ATTACK_KEY_COUNT].sector = cardAUTHSC;
ar_nr_resp[i+ATTACK_KEY_COUNT].keytype = cardAUTHKEY;
ar_nr_resp[i+ATTACK_KEY_COUNT].nonce = nonce;
ar_nr_resp[i+ATTACK_KEY_COUNT].nr = nr;
ar_nr_resp[i+ATTACK_KEY_COUNT].ar = ar;
ar_nr_collected[i+ATTACK_KEY_COUNT]++;
} else { // second nonce collect (std and moebius)
ar_nr_resp[i+mM].nonce2 = nonce;
ar_nr_resp[i+mM].nr2 = nr;
ar_nr_resp[i+mM].ar2 = ar;
if (!gettingMoebius) {
nonce2_count++;
// check if this was the last second nonce we need for std attack
if ( nonce2_count == nonce1_count ) {
// done collecting std test switch to moebius
// first finish incrementing last sample
ar_nr_collected[i+mM]++;
// switch to moebius collection
gettingMoebius = true;
mM = ATTACK_KEY_COUNT;
if (flags & FLAG_RANDOM_NONCE) {
nonce = prand();
} else {
nonce = nonce*7;
}
break;
}
} else {
moebius_n_count++;
// if we've collected all the nonces we need - finish.
if (nonce1_count == moebius_n_count) finished = true;
}
}
ar_nr_collected[i+mM]++;
}
}
// we found right spot for this nonce stop looking
break;
}
}
}
// --- crypto
crypto1_word(pcs, nr , 1);
cardRr = ar ^ crypto1_word(pcs, 0, 0);
// test if auth OK
if (cardRr != prng_successor(nonce, 64)){
if (MF_DBGLEVEL >= 2) Dbprintf("AUTH FAILED for sector %d with key %c. cardRr=%08x, succ=%08x",
cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B',
cardRr, prng_successor(nonce, 64));
// Shouldn't we respond anything here?
// Right now, we don't nack or anything, which causes the
// reader to do a WUPA after a while. /Martin
// -- which is the correct response. /piwi
cardAUTHKEY = 0xff; // not authenticated
cardSTATE_TO_IDLE();
break;
}
ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
num_to_bytes(ans, 4, rAUTH_AT);
EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED for sector %d with key %c.", cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B');
LED_C_ON();
cardSTATE = MFEMUL_WORK;
break;
}
case MFEMUL_WRITEBL2:{
if (receivedCmd_len == 18) {
mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, receivedCmd_dec);
if (HasValidCRC(receivedCmd_dec, receivedCmd_len)) {
emlSetMem(receivedCmd_dec, cardWRBL, 1);
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
cardSTATE = MFEMUL_WORK;
break;
}
}
cardSTATE_TO_IDLE();
break;
}
case MFEMUL_INTREG_INC:{
if (receivedCmd_len == 6) {
mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, (uint8_t*)&ans);
if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
cardSTATE_TO_IDLE();
break;
}
cardINTREG = cardINTREG + ans;
}
cardSTATE = MFEMUL_WORK;
break;
}
case MFEMUL_INTREG_DEC:{
if (receivedCmd_len == 6) {
mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, (uint8_t*)&ans);
if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
cardSTATE_TO_IDLE();
break;
}
}
cardINTREG = cardINTREG - ans;
cardSTATE = MFEMUL_WORK;
break;
}
case MFEMUL_INTREG_REST:{
mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, (uint8_t*)&ans);
if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
cardSTATE_TO_IDLE();
break;
}
cardSTATE = MFEMUL_WORK;
break;
}
}
button_pushed = BUTTON_PRESS();
}
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LEDsoff();
if(flags & FLAG_NR_AR_ATTACK && MF_DBGLEVEL >= 1) {
for ( uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
if (ar_nr_collected[i] == 2) {
Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x",
ar_nr_resp[i].cuid, //UID
ar_nr_resp[i].nonce, //NT
ar_nr_resp[i].nr, //NR1
ar_nr_resp[i].ar, //AR1
ar_nr_resp[i].nr2, //NR2
ar_nr_resp[i].ar2 //AR2
);
}
}
for ( uint8_t i = ATTACK_KEY_COUNT; i < ATTACK_KEY_COUNT*2; i++) {
if (ar_nr_collected[i] == 2) {
Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
Dbprintf("../tools/mfkey/mfkey32v2 %08x %08x %08x %08x %08x %08x %08x",
ar_nr_resp[i].cuid, //UID
ar_nr_resp[i].nonce, //NT
ar_nr_resp[i].nr, //NR1
ar_nr_resp[i].ar, //AR1
ar_nr_resp[i].nonce2,//NT2
ar_nr_resp[i].nr2, //NR2
ar_nr_resp[i].ar2 //AR2
);
}
}
}
if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", get_tracing(), BigBuf_get_traceLen());
if(flags & FLAG_INTERACTIVE) { // Interactive mode flag, means we need to send ACK
//Send the collected ar_nr in the response
cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,button_pushed,0,&ar_nr_resp,sizeof(ar_nr_resp));
}
}