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fix memory overflow in hf mf nested (issue #479)
[proxmark3-svn] / armsrc / mifaresim.c
1 //-----------------------------------------------------------------------------
2 // Merlok - June 2011, 2012
3 // Gerhard de Koning Gans - May 2008
4 // Hagen Fritsch - June 2010
5 //
6 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
7 // at your option, any later version. See the LICENSE.txt file for the text of
8 // the license.
9 //-----------------------------------------------------------------------------
10 // Mifare Classic Card Simulation
11 //-----------------------------------------------------------------------------
12
13 #include "mifaresim.h"
14 #include "iso14443a.h"
15 #include "iso14443crc.h"
16 #include "crapto1/crapto1.h"
17 #include "BigBuf.h"
18 #include "string.h"
19 #include "mifareutil.h"
20 #include "fpgaloader.h"
21 #include "proxmark3.h"
22 #include "usb_cdc.h"
23 #include "cmd.h"
24 #include "protocols.h"
25 #include "apps.h"
26
27 //mifare emulator states
28 #define MFEMUL_NOFIELD 0
29 #define MFEMUL_IDLE 1
30 #define MFEMUL_SELECT1 2
31 #define MFEMUL_SELECT2 3
32 #define MFEMUL_SELECT3 4
33 #define MFEMUL_AUTH1 5
34 #define MFEMUL_AUTH2 6
35 #define MFEMUL_WORK 7
36 #define MFEMUL_WRITEBL2 8
37 #define MFEMUL_INTREG_INC 9
38 #define MFEMUL_INTREG_DEC 10
39 #define MFEMUL_INTREG_REST 11
40 #define MFEMUL_HALTED 12
41
42 #define cardSTATE_TO_IDLE() { cardSTATE = MFEMUL_IDLE; LED_B_OFF(); LED_C_OFF(); }
43
44 #define AC_DATA_READ 0
45 #define AC_DATA_WRITE 1
46 #define AC_DATA_INC 2
47 #define AC_DATA_DEC_TRANS_REST 3
48 #define AC_KEYA_READ 0
49 #define AC_KEYA_WRITE 1
50 #define AC_KEYB_READ 2
51 #define AC_KEYB_WRITE 3
52 #define AC_AC_READ 4
53 #define AC_AC_WRITE 5
54
55 #define AUTHKEYA 0
56 #define AUTHKEYB 1
57 #define AUTHKEYNONE 0xff
58
59
60 static bool IsTrailerAccessAllowed(uint8_t blockNo, uint8_t keytype, uint8_t action) {
61 uint8_t sector_trailer[16];
62 emlGetMem(sector_trailer, blockNo, 1);
63 uint8_t AC = ((sector_trailer[7] >> 5) & 0x04)
64 | ((sector_trailer[8] >> 2) & 0x02)
65 | ((sector_trailer[8] >> 7) & 0x01);
66 switch (action) {
67 case AC_KEYA_READ: {
68 return false;
69 break;
70 }
71 case AC_KEYA_WRITE: {
72 return ((keytype == AUTHKEYA && (AC == 0x00 || AC == 0x01))
73 || (keytype == AUTHKEYB && (AC == 0x04 || AC == 0x03)));
74 break;
75 }
76 case AC_KEYB_READ: {
77 return (keytype == AUTHKEYA && (AC == 0x00 || AC == 0x02 || AC == 0x01));
78 break;
79 }
80 case AC_KEYB_WRITE: {
81 return ((keytype == AUTHKEYA && (AC == 0x00 || AC == 0x04))
82 || (keytype == AUTHKEYB && (AC == 0x04 || AC == 0x03)));
83 break;
84 }
85 case AC_AC_READ: {
86 return ((keytype == AUTHKEYA)
87 || (keytype == AUTHKEYB && !(AC == 0x00 || AC == 0x02 || AC == 0x01)));
88 break;
89 }
90 case AC_AC_WRITE: {
91 return ((keytype == AUTHKEYA && (AC == 0x01))
92 || (keytype == AUTHKEYB && (AC == 0x03 || AC == 0x05)));
93 break;
94 }
95 default: return false;
96 }
97 }
98
99
100 static bool IsDataAccessAllowed(uint8_t blockNo, uint8_t keytype, uint8_t action)
101 {
102 uint8_t sector_trailer[16];
103 emlGetMem(sector_trailer, SectorTrailer(blockNo), 1);
104
105 uint8_t sector_block;
106 if (blockNo < 32*4) {
107 sector_block = blockNo & 0x03;
108 } else {
109 sector_block = (blockNo & 0x0f) / 5;
110 }
111
112 uint8_t AC;
113 switch (sector_block) {
114 case 0x00: {
115 AC = ((sector_trailer[7] >> 2) & 0x04)
116 | ((sector_trailer[8] << 1) & 0x02)
117 | ((sector_trailer[8] >> 4) & 0x01);
118 break;
119 }
120 case 0x01: {
121 AC = ((sector_trailer[7] >> 3) & 0x04)
122 | ((sector_trailer[8] >> 0) & 0x02)
123 | ((sector_trailer[8] >> 5) & 0x01);
124 break;
125 }
126 case 0x02: {
127 AC = ((sector_trailer[7] >> 4) & 0x04)
128 | ((sector_trailer[8] >> 1) & 0x02)
129 | ((sector_trailer[8] >> 6) & 0x01);
130 break;
131 }
132 default:
133 return false;
134 }
135
136 switch (action) {
137 case AC_DATA_READ: {
138 return ((keytype == AUTHKEYA && !(AC == 0x03 || AC == 0x05 || AC == 0x07))
139 || (keytype == AUTHKEYB && !(AC == 0x07)));
140 break;
141 }
142 case AC_DATA_WRITE: {
143 return ((keytype == AUTHKEYA && (AC == 0x00))
144 || (keytype == AUTHKEYB && (AC == 0x00 || AC == 0x04 || AC == 0x06 || AC == 0x03)));
145 break;
146 }
147 case AC_DATA_INC: {
148 return ((keytype == AUTHKEYA && (AC == 0x00))
149 || (keytype == AUTHKEYB && (AC == 0x00 || AC == 0x06)));
150 break;
151 }
152 case AC_DATA_DEC_TRANS_REST: {
153 return ((keytype == AUTHKEYA && (AC == 0x00 || AC == 0x06 || AC == 0x01))
154 || (keytype == AUTHKEYB && (AC == 0x00 || AC == 0x06 || AC == 0x01)));
155 break;
156 }
157 }
158
159 return false;
160 }
161
162
163 static bool IsAccessAllowed(uint8_t blockNo, uint8_t keytype, uint8_t action) {
164 if (IsSectorTrailer(blockNo)) {
165 return IsTrailerAccessAllowed(blockNo, keytype, action);
166 } else {
167 return IsDataAccessAllowed(blockNo, keytype, action);
168 }
169 }
170
171
172 static void MifareSimInit(uint8_t flags, uint8_t *datain, tag_response_info_t **responses, uint32_t *cuid, uint8_t *uid_len) {
173
174 #define TAG_RESPONSE_COUNT 5 // number of precompiled responses
175 static uint8_t rATQA[] = {0x04, 0x00}; // indicate Mifare classic 1k 4Byte UID
176 static uint8_t rUIDBCC1[] = {0x00, 0x00, 0x00, 0x00, 0x00}; // UID 1st cascade level
177 static uint8_t rUIDBCC2[] = {0x00, 0x00, 0x00, 0x00, 0x00}; // UID 2nd cascade level
178 static uint8_t rSAKfinal[]= {0x08, 0xb6, 0xdd}; // mifare 1k indicated
179 static uint8_t rSAK1[] = {0x04, 0xda, 0x17}; // indicate UID not finished
180
181 *uid_len = 4;
182 // UID can be set from emulator memory or incoming data and can be 4 or 7 bytes long
183 if (flags & FLAG_4B_UID_IN_DATA) { // get UID from datain
184 memcpy(rUIDBCC1, datain, 4);
185 } else if (flags & FLAG_7B_UID_IN_DATA) {
186 rUIDBCC1[0] = 0x88;
187 memcpy(rUIDBCC1+1, datain, 3);
188 memcpy(rUIDBCC2, datain+3, 4);
189 *uid_len = 7;
190 } else {
191 uint8_t probable_atqa;
192 emlGetMemBt(&probable_atqa, 7, 1); // get UID from emul memory - weak guess at length
193 if (probable_atqa == 0x00) { // ---------- 4BUID
194 emlGetMemBt(rUIDBCC1, 0, 4);
195 } else { // ---------- 7BUID
196 rUIDBCC1[0] = 0x88;
197 emlGetMemBt(rUIDBCC1+1, 0, 3);
198 emlGetMemBt(rUIDBCC2, 3, 4);
199 *uid_len = 7;
200 }
201 }
202
203 switch (*uid_len) {
204 case 4:
205 *cuid = bytes_to_num(rUIDBCC1, 4);
206 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
207 if (MF_DBGLEVEL >= 2) {
208 Dbprintf("4B UID: %02x%02x%02x%02x",
209 rUIDBCC1[0], rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3] );
210 }
211 break;
212 case 7:
213 rATQA[0] |= 0x40;
214 *cuid = bytes_to_num(rUIDBCC2, 4);
215 rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
216 rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
217 if (MF_DBGLEVEL >= 2) {
218 Dbprintf("7B UID: %02x %02x %02x %02x %02x %02x %02x",
219 rUIDBCC1[1], rUIDBCC1[2], rUIDBCC1[3], rUIDBCC2[0], rUIDBCC2[1], rUIDBCC2[2], rUIDBCC2[3] );
220 }
221 break;
222 default:
223 break;
224 }
225
226 static tag_response_info_t responses_init[TAG_RESPONSE_COUNT] = {
227 { .response = rATQA, .response_n = sizeof(rATQA) }, // Answer to request - respond with card type
228 { .response = rUIDBCC1, .response_n = sizeof(rUIDBCC1) }, // Anticollision cascade1 - respond with first part of uid
229 { .response = rUIDBCC2, .response_n = sizeof(rUIDBCC2) }, // Anticollision cascade2 - respond with 2nd part of uid
230 { .response = rSAKfinal, .response_n = sizeof(rSAKfinal) }, // Acknowledge select - last cascade
231 { .response = rSAK1, .response_n = sizeof(rSAK1) } // Acknowledge select - previous cascades
232 };
233
234 // 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
235 // 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)
236 // 18 * 8 data bits, 18 * 1 parity bits, 5 start bits, 5 stop bits, 5 correction bits -> need 177 bytes buffer
237 #define ALLOCATED_TAG_MODULATION_BUFFER_SIZE 177 // number of bytes required for precompiled responses
238
239 uint8_t *free_buffer_pointer = BigBuf_malloc(ALLOCATED_TAG_MODULATION_BUFFER_SIZE);
240 size_t free_buffer_size = ALLOCATED_TAG_MODULATION_BUFFER_SIZE;
241 for (size_t i = 0; i < TAG_RESPONSE_COUNT; i++) {
242 prepare_allocated_tag_modulation(&responses_init[i], &free_buffer_pointer, &free_buffer_size);
243 }
244
245 *responses = responses_init;
246
247 // indices into responses array:
248 #define ATQA 0
249 #define UIDBCC1 1
250 #define UIDBCC2 2
251 #define SAKfinal 3
252 #define SAK1 4
253
254 }
255
256
257 static bool HasValidCRC(uint8_t *receivedCmd, uint16_t receivedCmd_len) {
258 uint8_t CRC_byte_1, CRC_byte_2;
259 ComputeCrc14443(CRC_14443_A, receivedCmd, receivedCmd_len-2, &CRC_byte_1, &CRC_byte_2);
260 return (receivedCmd[receivedCmd_len-2] == CRC_byte_1 && receivedCmd[receivedCmd_len-1] == CRC_byte_2);
261 }
262
263
264 /**
265 *MIFARE 1K simulate.
266 *
267 *@param flags :
268 * FLAG_INTERACTIVE - In interactive mode, we are expected to finish the operation with an ACK
269 * FLAG_4B_UID_IN_DATA - means that there is a 4-byte UID in the data-section, we're expected to use that
270 * FLAG_7B_UID_IN_DATA - means that there is a 7-byte UID in the data-section, we're expected to use that
271 * FLAG_10B_UID_IN_DATA - use 10-byte UID in the data-section not finished
272 * FLAG_NR_AR_ATTACK - means we should collect NR_AR responses for bruteforcing later
273 * FLAG_RANDOM_NONCE - means we should generate some pseudo-random nonce data (only allows moebius attack)
274 *@param exitAfterNReads, exit simulation after n blocks have been read, 0 is infinite ...
275 * (unless reader attack mode enabled then it runs util it gets enough nonces to recover all keys attmpted)
276 */
277 void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain)
278 {
279 tag_response_info_t *responses;
280 uint8_t uid_len = 4;
281 uint32_t cuid = 0;
282 uint8_t cardWRBL = 0;
283 uint8_t cardAUTHSC = 0;
284 uint8_t cardAUTHKEY = AUTHKEYNONE; // no authentication
285 uint32_t cardRr = 0;
286 //uint32_t rn_enc = 0;
287 uint32_t ans = 0;
288 uint32_t cardINTREG = 0;
289 uint8_t cardINTBLOCK = 0;
290 struct Crypto1State mpcs = {0, 0};
291 struct Crypto1State *pcs;
292 pcs = &mpcs;
293 uint32_t numReads = 0;//Counts numer of times reader reads a block
294 uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE];
295 uint8_t receivedCmd_dec[MAX_MIFARE_FRAME_SIZE];
296 uint8_t receivedCmd_par[MAX_MIFARE_PARITY_SIZE];
297 uint16_t receivedCmd_len;
298 uint8_t response[MAX_MIFARE_FRAME_SIZE];
299 uint8_t response_par[MAX_MIFARE_PARITY_SIZE];
300
301 uint8_t rAUTH_NT[] = {0x01, 0x02, 0x03, 0x04};
302 uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
303
304 //Here, we collect UID,sector,keytype,NT,AR,NR,NT2,AR2,NR2
305 // This will be used in the reader-only attack.
306
307 //allow collecting up to 7 sets of nonces to allow recovery of up to 7 keys
308 #define ATTACK_KEY_COUNT 7 // keep same as define in cmdhfmf.c -> readerAttack() (Cannot be more than 7)
309 nonces_t ar_nr_resp[ATTACK_KEY_COUNT*2]; //*2 for 2 separate attack types (nml, moebius) 36 * 7 * 2 bytes = 504 bytes
310 memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp));
311
312 uint8_t ar_nr_collected[ATTACK_KEY_COUNT*2]; //*2 for 2nd attack type (moebius)
313 memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected));
314 uint8_t nonce1_count = 0;
315 uint8_t nonce2_count = 0;
316 uint8_t moebius_n_count = 0;
317 bool gettingMoebius = false;
318 uint8_t mM = 0; //moebius_modifier for collection storage
319
320 // Authenticate response - nonce
321 uint32_t nonce;
322 if (flags & FLAG_RANDOM_NONCE) {
323 nonce = prand();
324 } else {
325 nonce = bytes_to_num(rAUTH_NT, 4);
326 }
327
328 // free eventually allocated BigBuf memory but keep Emulator Memory
329 BigBuf_free_keep_EM();
330
331 MifareSimInit(flags, datain, &responses, &cuid, &uid_len);
332
333 // We need to listen to the high-frequency, peak-detected path.
334 iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
335
336 // clear trace
337 clear_trace();
338 set_tracing(true);
339 ResetSspClk();
340
341 bool finished = false;
342 bool button_pushed = BUTTON_PRESS();
343 int cardSTATE = MFEMUL_NOFIELD;
344
345 while (!button_pushed && !finished && !usb_poll_validate_length()) {
346 WDT_HIT();
347
348 // find reader field
349 if (cardSTATE == MFEMUL_NOFIELD) {
350 int vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
351 if (vHf > MF_MINFIELDV) {
352 LED_A_ON();
353 cardSTATE_TO_IDLE();
354 }
355 button_pushed = BUTTON_PRESS();
356 continue;
357 }
358
359 //Now, get data
360 int res = EmGetCmd(receivedCmd, &receivedCmd_len, receivedCmd_par);
361
362 if (res == 2) { //Field is off!
363 LEDsoff();
364 cardSTATE = MFEMUL_NOFIELD;
365 continue;
366 } else if (res == 1) { // button pressed
367 button_pushed = true;
368 break;
369 }
370
371 // WUPA in HALTED state or REQA or WUPA in any other state
372 if (receivedCmd_len == 1 && ((receivedCmd[0] == ISO14443A_CMD_REQA && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == ISO14443A_CMD_WUPA)) {
373 EmSendPrecompiledCmd(&responses[ATQA]);
374
375 // init crypto block
376 crypto1_destroy(pcs);
377 cardAUTHKEY = AUTHKEYNONE;
378 if (flags & FLAG_RANDOM_NONCE) {
379 nonce = prand();
380 }
381 LED_B_OFF();
382 LED_C_OFF();
383 cardSTATE = MFEMUL_SELECT1;
384 continue;
385 }
386
387 switch (cardSTATE) {
388 case MFEMUL_NOFIELD:
389 case MFEMUL_HALTED:
390 case MFEMUL_IDLE:{
391 break;
392 }
393 case MFEMUL_SELECT1:{
394 // select all - 0x93 0x20
395 if (receivedCmd_len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x20)) {
396 if (MF_DBGLEVEL >= 4) Dbprintf("SELECT ALL CL1 received");
397 EmSendPrecompiledCmd(&responses[UIDBCC1]);
398 break;
399 }
400 // select card - 0x93 0x70 ...
401 if (receivedCmd_len == 9 &&
402 (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], responses[UIDBCC1].response, 4) == 0)) {
403 if (MF_DBGLEVEL >= 4) Dbprintf("SELECT CL1 %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]);
404 if (uid_len == 4) {
405 EmSendPrecompiledCmd(&responses[SAKfinal]);
406 LED_B_ON();
407 cardSTATE = MFEMUL_WORK;
408 break;
409 } else if (uid_len == 7) {
410 EmSendPrecompiledCmd(&responses[SAK1]);
411 cardSTATE = MFEMUL_SELECT2;
412 break;
413 }
414 }
415 cardSTATE_TO_IDLE();
416 break;
417 }
418 case MFEMUL_SELECT2:{
419 // select all cl2 - 0x95 0x20
420 if (receivedCmd_len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x20)) {
421 if (MF_DBGLEVEL >= 4) Dbprintf("SELECT ALL CL2 received");
422 EmSendPrecompiledCmd(&responses[UIDBCC2]);
423 break;
424 }
425 // select cl2 card - 0x95 0x70 xxxxxxxxxxxx
426 if (receivedCmd_len == 9 &&
427 (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], responses[UIDBCC2].response, 4) == 0)) {
428 if (uid_len == 7) {
429 if (MF_DBGLEVEL >= 4) Dbprintf("SELECT CL2 %02x%02x%02x%02x received",receivedCmd[2],receivedCmd[3],receivedCmd[4],receivedCmd[5]);
430 EmSendPrecompiledCmd(&responses[SAKfinal]);
431 LED_B_ON();
432 cardSTATE = MFEMUL_WORK;
433 break;
434 }
435 }
436 cardSTATE_TO_IDLE();
437 break;
438 }
439 case MFEMUL_WORK:{
440 if (receivedCmd_len != 4) { // all commands must have exactly 4 bytes
441 break;
442 }
443 bool encrypted_data = (cardAUTHKEY != AUTHKEYNONE) ;
444 if (encrypted_data) {
445 // decrypt seqence
446 mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, receivedCmd_dec);
447 } else {
448 memcpy(receivedCmd_dec, receivedCmd, receivedCmd_len);
449 }
450 if (!HasValidCRC(receivedCmd_dec, receivedCmd_len)) { // all commands must have a valid CRC
451 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
452 break;
453 }
454 if (receivedCmd_dec[0] == MIFARE_AUTH_KEYA || receivedCmd_dec[0] == MIFARE_AUTH_KEYB) {
455 // if authenticating to a block that shouldn't exist - as long as we are not doing the reader attack
456 if (receivedCmd_dec[1] >= 16 * 4 && !(flags & FLAG_NR_AR_ATTACK)) {
457 //is this the correct response to an auth on a out of range block? marshmellow
458 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
459 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]);
460 break;
461 }
462 cardAUTHSC = receivedCmd_dec[1] / 4; // received block num
463 cardAUTHKEY = receivedCmd_dec[0] & 0x01;
464 crypto1_destroy(pcs);//Added by martin
465 crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
466 if (!encrypted_data) { // first authentication
467 if (MF_DBGLEVEL >= 4) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd_dec[1], receivedCmd_dec[1], cardAUTHKEY);
468 crypto1_word(pcs, cuid ^ nonce, 0);//Update crypto state
469 num_to_bytes(nonce, 4, rAUTH_AT); // Send nonce
470 } else { // nested authentication
471 if (MF_DBGLEVEL >= 4) Dbprintf("Reader doing nested authentication for block %d (0x%02x) with key %d", receivedCmd_dec[1], receivedCmd_dec[1], cardAUTHKEY);
472 ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0);
473 num_to_bytes(ans, 4, rAUTH_AT);
474 }
475 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
476 cardSTATE = MFEMUL_AUTH1;
477 break;
478 }
479 if (!encrypted_data) { // all other commands must be encrypted (authenticated)
480 break;
481 }
482 if(receivedCmd_dec[0] == ISO14443A_CMD_READBLOCK
483 || receivedCmd_dec[0] == ISO14443A_CMD_WRITEBLOCK
484 || receivedCmd_dec[0] == MIFARE_CMD_INC
485 || receivedCmd_dec[0] == MIFARE_CMD_DEC
486 || receivedCmd_dec[0] == MIFARE_CMD_RESTORE
487 || receivedCmd_dec[0] == MIFARE_CMD_TRANSFER) {
488 if (receivedCmd_dec[1] >= 16 * 4) {
489 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
490 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]);
491 break;
492 }
493 if (receivedCmd_dec[1] / 4 != cardAUTHSC) {
494 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
495 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);
496 break;
497 }
498 }
499 if (receivedCmd_dec[0] == ISO14443A_CMD_READBLOCK) {
500 uint8_t blockNo = receivedCmd_dec[1];
501 if (MF_DBGLEVEL >= 4) {
502 Dbprintf("Reader reading block %d (0x%02x)", blockNo, blockNo);
503 }
504 emlGetMem(response, blockNo, 1);
505 if (IsSectorTrailer(blockNo)) {
506 memset(response, 0x00, 6); // keyA can never be read
507 if (!IsAccessAllowed(blockNo, cardAUTHKEY, AC_KEYB_READ)) {
508 memset(response+10, 0x00, 6); // keyB cannot be read
509 }
510 if (!IsAccessAllowed(blockNo, cardAUTHKEY, AC_AC_READ)) {
511 memset(response+6, 0x00, 4); // AC bits cannot be read
512 }
513 } else {
514 if (!IsAccessAllowed(blockNo, cardAUTHKEY, AC_DATA_READ)) {
515 memset(response, 0x00, 16); // datablock cannot be read
516 }
517 }
518 AppendCrc14443a(response, 16);
519 mf_crypto1_encrypt(pcs, response, 18, response_par);
520 EmSendCmdPar(response, 18, response_par);
521 numReads++;
522 if(exitAfterNReads > 0 && numReads == exitAfterNReads) {
523 Dbprintf("%d reads done, exiting", numReads);
524 finished = true;
525 }
526 break;
527 }
528 if (receivedCmd_dec[0] == ISO14443A_CMD_WRITEBLOCK) {
529 uint8_t blockNo = receivedCmd_dec[1];
530 if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0xA0 write block %d (%02x)", blockNo, blockNo);
531 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
532 cardWRBL = blockNo;
533 cardSTATE = MFEMUL_WRITEBL2;
534 break;
535 }
536 if (receivedCmd_dec[0] == MIFARE_CMD_INC || receivedCmd_dec[0] == MIFARE_CMD_DEC || receivedCmd_dec[0] == MIFARE_CMD_RESTORE) {
537 uint8_t blockNo = receivedCmd_dec[1];
538 if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x inc(0xC1)/dec(0xC0)/restore(0xC2) block %d (%02x)",receivedCmd_dec[0], blockNo, blockNo);
539 if (emlCheckValBl(blockNo)) {
540 if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate on block, but emlCheckValBl failed, nacking");
541 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
542 break;
543 }
544 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
545 cardWRBL = blockNo;
546 if (receivedCmd_dec[0] == MIFARE_CMD_INC)
547 cardSTATE = MFEMUL_INTREG_INC;
548 if (receivedCmd_dec[0] == MIFARE_CMD_DEC)
549 cardSTATE = MFEMUL_INTREG_DEC;
550 if (receivedCmd_dec[0] == MIFARE_CMD_RESTORE)
551 cardSTATE = MFEMUL_INTREG_REST;
552 break;
553 }
554 if (receivedCmd_dec[0] == MIFARE_CMD_TRANSFER) {
555 uint8_t blockNo = receivedCmd_dec[1];
556 if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x transfer block %d (%02x)",receivedCmd_dec[0], blockNo, blockNo);
557 if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd_dec[1]))
558 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
559 else
560 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
561 break;
562 }
563 // halt
564 if (receivedCmd_dec[0] == ISO14443A_CMD_HALT && receivedCmd_dec[1] == 0x00) {
565 if (MF_DBGLEVEL >= 4) Dbprintf("--> HALTED.");
566 LED_B_OFF();
567 LED_C_OFF();
568 cardSTATE = MFEMUL_HALTED;
569 break;
570 }
571 // command not allowed
572 if (MF_DBGLEVEL >= 4) Dbprintf("Received command not allowed, nacking");
573 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
574 break;
575 }
576 case MFEMUL_AUTH1:{
577 if (receivedCmd_len != 8) {
578 cardSTATE_TO_IDLE();
579 break;
580 }
581
582 uint32_t nr = bytes_to_num(receivedCmd, 4);
583 uint32_t ar = bytes_to_num(&receivedCmd[4], 4);
584
585 // Collect AR/NR per keytype & sector
586 if(flags & FLAG_NR_AR_ATTACK) {
587 for (uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
588 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)) ) {
589 // if first auth for sector, or matches sector and keytype of previous auth
590 if (ar_nr_collected[i+mM] < 2) {
591 // if we haven't already collected 2 nonces for this sector
592 if (ar_nr_resp[ar_nr_collected[i+mM]].ar != ar) {
593 // Avoid duplicates... probably not necessary, ar should vary.
594 if (ar_nr_collected[i+mM]==0) {
595 // first nonce collect
596 ar_nr_resp[i+mM].cuid = cuid;
597 ar_nr_resp[i+mM].sector = cardAUTHSC;
598 ar_nr_resp[i+mM].keytype = cardAUTHKEY;
599 ar_nr_resp[i+mM].nonce = nonce;
600 ar_nr_resp[i+mM].nr = nr;
601 ar_nr_resp[i+mM].ar = ar;
602 nonce1_count++;
603 // add this nonce to first moebius nonce
604 ar_nr_resp[i+ATTACK_KEY_COUNT].cuid = cuid;
605 ar_nr_resp[i+ATTACK_KEY_COUNT].sector = cardAUTHSC;
606 ar_nr_resp[i+ATTACK_KEY_COUNT].keytype = cardAUTHKEY;
607 ar_nr_resp[i+ATTACK_KEY_COUNT].nonce = nonce;
608 ar_nr_resp[i+ATTACK_KEY_COUNT].nr = nr;
609 ar_nr_resp[i+ATTACK_KEY_COUNT].ar = ar;
610 ar_nr_collected[i+ATTACK_KEY_COUNT]++;
611 } else { // second nonce collect (std and moebius)
612 ar_nr_resp[i+mM].nonce2 = nonce;
613 ar_nr_resp[i+mM].nr2 = nr;
614 ar_nr_resp[i+mM].ar2 = ar;
615 if (!gettingMoebius) {
616 nonce2_count++;
617 // check if this was the last second nonce we need for std attack
618 if ( nonce2_count == nonce1_count ) {
619 // done collecting std test switch to moebius
620 // first finish incrementing last sample
621 ar_nr_collected[i+mM]++;
622 // switch to moebius collection
623 gettingMoebius = true;
624 mM = ATTACK_KEY_COUNT;
625 if (flags & FLAG_RANDOM_NONCE) {
626 nonce = prand();
627 } else {
628 nonce = nonce*7;
629 }
630 break;
631 }
632 } else {
633 moebius_n_count++;
634 // if we've collected all the nonces we need - finish.
635 if (nonce1_count == moebius_n_count) finished = true;
636 }
637 }
638 ar_nr_collected[i+mM]++;
639 }
640 }
641 // we found right spot for this nonce stop looking
642 break;
643 }
644 }
645 }
646
647 // --- crypto
648 crypto1_word(pcs, nr , 1);
649 cardRr = ar ^ crypto1_word(pcs, 0, 0);
650
651 // test if auth OK
652 if (cardRr != prng_successor(nonce, 64)){
653 if (MF_DBGLEVEL >= 2) Dbprintf("AUTH FAILED for sector %d with key %c. cardRr=%08x, succ=%08x",
654 cardAUTHSC, cardAUTHKEY == AUTHKEYA ? 'A' : 'B',
655 cardRr, prng_successor(nonce, 64));
656 // Shouldn't we respond anything here?
657 // Right now, we don't nack or anything, which causes the
658 // reader to do a WUPA after a while. /Martin
659 // -- which is the correct response. /piwi
660 cardAUTHKEY = AUTHKEYNONE; // not authenticated
661 cardSTATE_TO_IDLE();
662 break;
663 }
664 ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
665 num_to_bytes(ans, 4, rAUTH_AT);
666 EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
667 if (MF_DBGLEVEL >= 4) Dbprintf("AUTH COMPLETED for sector %d with key %c.", cardAUTHSC, cardAUTHKEY == AUTHKEYA ? 'A' : 'B');
668 LED_C_ON();
669 cardSTATE = MFEMUL_WORK;
670 break;
671 }
672 case MFEMUL_WRITEBL2:{
673 if (receivedCmd_len == 18) {
674 mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, receivedCmd_dec);
675 if (HasValidCRC(receivedCmd_dec, receivedCmd_len)) {
676 if (IsSectorTrailer(cardWRBL)) {
677 emlGetMem(response, cardWRBL, 1);
678 if (!IsAccessAllowed(cardWRBL, cardAUTHKEY, AC_KEYA_WRITE)) {
679 memcpy(receivedCmd_dec, response, 6); // don't change KeyA
680 }
681 if (!IsAccessAllowed(cardWRBL, cardAUTHKEY, AC_KEYB_WRITE)) {
682 memcpy(receivedCmd_dec+10, response+10, 6); // don't change KeyA
683 }
684 if (!IsAccessAllowed(cardWRBL, cardAUTHKEY, AC_AC_WRITE)) {
685 memcpy(receivedCmd_dec+6, response+6, 4); // don't change AC bits
686 }
687 } else {
688 if (!IsAccessAllowed(cardWRBL, cardAUTHKEY, AC_DATA_WRITE)) {
689 memcpy(receivedCmd_dec, response, 16); // don't change anything
690 }
691 }
692 emlSetMem(receivedCmd_dec, cardWRBL, 1);
693 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK)); // always ACK?
694 cardSTATE = MFEMUL_WORK;
695 break;
696 }
697 }
698 cardSTATE_TO_IDLE();
699 break;
700 }
701 case MFEMUL_INTREG_INC:{
702 if (receivedCmd_len == 6) {
703 mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, (uint8_t*)&ans);
704 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
705 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
706 cardSTATE_TO_IDLE();
707 break;
708 }
709 cardINTREG = cardINTREG + ans;
710 }
711 cardSTATE = MFEMUL_WORK;
712 break;
713 }
714 case MFEMUL_INTREG_DEC:{
715 if (receivedCmd_len == 6) {
716 mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, (uint8_t*)&ans);
717 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
718 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
719 cardSTATE_TO_IDLE();
720 break;
721 }
722 }
723 cardINTREG = cardINTREG - ans;
724 cardSTATE = MFEMUL_WORK;
725 break;
726 }
727 case MFEMUL_INTREG_REST:{
728 mf_crypto1_decryptEx(pcs, receivedCmd, receivedCmd_len, (uint8_t*)&ans);
729 if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
730 EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
731 cardSTATE_TO_IDLE();
732 break;
733 }
734 cardSTATE = MFEMUL_WORK;
735 break;
736 }
737 }
738 button_pushed = BUTTON_PRESS();
739 }
740
741 FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
742 LEDsoff();
743
744 if(flags & FLAG_NR_AR_ATTACK && MF_DBGLEVEL >= 1) {
745 for ( uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
746 if (ar_nr_collected[i] == 2) {
747 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);
748 Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x",
749 ar_nr_resp[i].cuid, //UID
750 ar_nr_resp[i].nonce, //NT
751 ar_nr_resp[i].nr, //NR1
752 ar_nr_resp[i].ar, //AR1
753 ar_nr_resp[i].nr2, //NR2
754 ar_nr_resp[i].ar2 //AR2
755 );
756 }
757 }
758 for ( uint8_t i = ATTACK_KEY_COUNT; i < ATTACK_KEY_COUNT*2; i++) {
759 if (ar_nr_collected[i] == 2) {
760 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);
761 Dbprintf("../tools/mfkey/mfkey32v2 %08x %08x %08x %08x %08x %08x %08x",
762 ar_nr_resp[i].cuid, //UID
763 ar_nr_resp[i].nonce, //NT
764 ar_nr_resp[i].nr, //NR1
765 ar_nr_resp[i].ar, //AR1
766 ar_nr_resp[i].nonce2,//NT2
767 ar_nr_resp[i].nr2, //NR2
768 ar_nr_resp[i].ar2 //AR2
769 );
770 }
771 }
772 }
773 if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d trace length: %d ", get_tracing(), BigBuf_get_traceLen());
774
775 if(flags & FLAG_INTERACTIVE) { // Interactive mode flag, means we need to send ACK
776 //Send the collected ar_nr in the response
777 cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,button_pushed,0,&ar_nr_resp,sizeof(ar_nr_resp));
778 }
779 }
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