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FIX: Coverity scans, uninitialized variables,
[proxmark3-svn] / client / cmdhfmfhard.c
1 //-----------------------------------------------------------------------------
2 // Copyright (C) 2015 piwi
3 //
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
6 // the license.
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 //-----------------------------------------------------------------------------
16
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <string.h>
20 #include <pthread.h>
21 #include <locale.h>
22 #include <math.h>
23 #include "proxmark3.h"
24 #include "cmdmain.h"
25 #include "ui.h"
26 #include "util.h"
27 #include "nonce2key/crapto1.h"
28 #include "parity.h"
29
30 // uint32_t test_state_odd = 0;
31 // uint32_t test_state_even = 0;
32
33 #define CONFIDENCE_THRESHOLD 0.95 // Collect nonces until we are certain enough that the following brute force is successfull
34 #define GOOD_BYTES_REQUIRED 30
35
36
37 static const float p_K[257] = { // the probability that a random nonce has a Sum Property == K
38 0.0290, 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 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
42 0.0083, 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 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
45 0.0006, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
46 0.0339, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
47 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
48 0.0048, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
49 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
50 0.0934, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
51 0.0119, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
52 0.0489, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
53 0.0602, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
54 0.4180, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
55 0.0602, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
56 0.0489, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
57 0.0119, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
58 0.0934, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
59 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
60 0.0048, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
61 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
62 0.0339, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
63 0.0006, 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 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
66 0.0083, 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,
69 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000,
70 0.0290 };
71
72
73 typedef struct noncelistentry {
74 uint32_t nonce_enc;
75 uint8_t par_enc;
76 void *next;
77 } noncelistentry_t;
78
79 typedef struct noncelist {
80 uint16_t num;
81 uint16_t Sum;
82 uint16_t Sum8_guess;
83 uint8_t BitFlip[2];
84 float Sum8_prob;
85 bool updated;
86 noncelistentry_t *first;
87 float score1, score2;
88 } noncelist_t;
89
90
91 static uint32_t cuid;
92 static noncelist_t nonces[256];
93 static uint8_t best_first_bytes[256];
94 static uint16_t first_byte_Sum = 0;
95 static uint16_t first_byte_num = 0;
96 static uint16_t num_good_first_bytes = 0;
97 static uint64_t maximum_states = 0;
98 static uint64_t known_target_key;
99 static bool write_stats = false;
100 static FILE *fstats = NULL;
101
102
103 typedef enum {
104 EVEN_STATE = 0,
105 ODD_STATE = 1
106 } odd_even_t;
107
108 #define STATELIST_INDEX_WIDTH 16
109 #define STATELIST_INDEX_SIZE (1<<STATELIST_INDEX_WIDTH)
110
111 typedef struct {
112 uint32_t *states[2];
113 uint32_t len[2];
114 uint32_t *index[2][STATELIST_INDEX_SIZE];
115 } partial_indexed_statelist_t;
116
117 typedef struct {
118 uint32_t *states[2];
119 uint32_t len[2];
120 void* next;
121 } statelist_t;
122
123
124 static partial_indexed_statelist_t partial_statelist[17];
125 static partial_indexed_statelist_t statelist_bitflip;
126
127 static statelist_t *candidates = NULL;
128
129
130 static int add_nonce(uint32_t nonce_enc, uint8_t par_enc)
131 {
132 uint8_t first_byte = nonce_enc >> 24;
133 noncelistentry_t *p1 = nonces[first_byte].first;
134 noncelistentry_t *p2 = NULL;
135
136 if (p1 == NULL) { // first nonce with this 1st byte
137 first_byte_num++;
138 first_byte_Sum += evenparity32((nonce_enc & 0xff000000) | (par_enc & 0x08));
139 // printf("Adding nonce 0x%08x, par_enc 0x%02x, parity(0x%08x) = %d\n",
140 // nonce_enc,
141 // par_enc,
142 // (nonce_enc & 0xff000000) | (par_enc & 0x08) |0x01,
143 // parity((nonce_enc & 0xff000000) | (par_enc & 0x08));
144 }
145
146 while (p1 != NULL && (p1->nonce_enc & 0x00ff0000) < (nonce_enc & 0x00ff0000)) {
147 p2 = p1;
148 p1 = p1->next;
149 }
150
151 if (p1 == NULL) { // need to add at the end of the list
152 if (p2 == NULL) { // list is empty yet. Add first entry.
153 p2 = nonces[first_byte].first = malloc(sizeof(noncelistentry_t));
154 } else { // add new entry at end of existing list.
155 p2 = p2->next = malloc(sizeof(noncelistentry_t));
156 }
157 } else if ((p1->nonce_enc & 0x00ff0000) != (nonce_enc & 0x00ff0000)) { // found distinct 2nd byte. Need to insert.
158 if (p2 == NULL) { // need to insert at start of list
159 p2 = nonces[first_byte].first = malloc(sizeof(noncelistentry_t));
160 } else {
161 p2 = p2->next = malloc(sizeof(noncelistentry_t));
162 }
163 } else { // we have seen this 2nd byte before. Nothing to add or insert.
164 return (0);
165 }
166
167 // add or insert new data
168 p2->next = p1;
169 p2->nonce_enc = nonce_enc;
170 p2->par_enc = par_enc;
171
172 nonces[first_byte].num++;
173 nonces[first_byte].Sum += evenparity32((nonce_enc & 0x00ff0000) | (par_enc & 0x04));
174 nonces[first_byte].updated = true; // indicates that we need to recalculate the Sum(a8) probability for this first byte
175
176 return (1); // new nonce added
177 }
178
179
180 static void init_nonce_memory(void)
181 {
182 for (uint16_t i = 0; i < 256; i++) {
183 nonces[i].num = 0;
184 nonces[i].Sum = 0;
185 nonces[i].Sum8_guess = 0;
186 nonces[i].Sum8_prob = 0.0;
187 nonces[i].updated = true;
188 nonces[i].first = NULL;
189 }
190 first_byte_num = 0;
191 first_byte_Sum = 0;
192 num_good_first_bytes = 0;
193 }
194
195
196 static void free_nonce_list(noncelistentry_t *p)
197 {
198 if (p == NULL) {
199 return;
200 } else {
201 free_nonce_list(p->next);
202 free(p);
203 }
204 }
205
206
207 static void free_nonces_memory(void)
208 {
209 for (uint16_t i = 0; i < 256; i++) {
210 free_nonce_list(nonces[i].first);
211 }
212 }
213
214
215 static uint16_t PartialSumProperty(uint32_t state, odd_even_t odd_even)
216 {
217 uint16_t sum = 0;
218 for (uint16_t j = 0; j < 16; j++) {
219 uint32_t st = state;
220 uint16_t part_sum = 0;
221 if (odd_even == ODD_STATE) {
222 for (uint16_t i = 0; i < 5; i++) {
223 part_sum ^= filter(st);
224 st = (st << 1) | ((j >> (3-i)) & 0x01) ;
225 }
226 part_sum ^= 1; // XOR 1 cancelled out for the other 8 bits
227 } else {
228 for (uint16_t i = 0; i < 4; i++) {
229 st = (st << 1) | ((j >> (3-i)) & 0x01) ;
230 part_sum ^= filter(st);
231 }
232 }
233 sum += part_sum;
234 }
235 return sum;
236 }
237
238
239 // static uint16_t SumProperty(struct Crypto1State *s)
240 // {
241 // uint16_t sum_odd = PartialSumProperty(s->odd, ODD_STATE);
242 // uint16_t sum_even = PartialSumProperty(s->even, EVEN_STATE);
243 // return (sum_odd*(16-sum_even) + (16-sum_odd)*sum_even);
244 // }
245
246
247 static double p_hypergeometric(uint16_t N, uint16_t K, uint16_t n, uint16_t k)
248 {
249 // for efficient computation we are using the recursive definition
250 // (K-k+1) * (n-k+1)
251 // P(X=k) = P(X=k-1) * --------------------
252 // k * (N-K-n+k)
253 // and
254 // (N-K)*(N-K-1)*...*(N-K-n+1)
255 // P(X=0) = -----------------------------
256 // N*(N-1)*...*(N-n+1)
257
258 if (n-k > N-K || k > K) return 0.0; // avoids log(x<=0) in calculation below
259 if (k == 0) {
260 // use logarithms to avoid overflow with huge factorials (double type can only hold 170!)
261 double log_result = 0.0;
262 for (int16_t i = N-K; i >= N-K-n+1; i--) {
263 log_result += log(i);
264 }
265 for (int16_t i = N; i >= N-n+1; i--) {
266 log_result -= log(i);
267 }
268 return exp(log_result);
269 } else {
270 if (n-k == N-K) { // special case. The published recursion below would fail with a divide by zero exception
271 double log_result = 0.0;
272 for (int16_t i = k+1; i <= n; i++) {
273 log_result += log(i);
274 }
275 for (int16_t i = K+1; i <= N; i++) {
276 log_result -= log(i);
277 }
278 return exp(log_result);
279 } else { // recursion
280 return (p_hypergeometric(N, K, n, k-1) * (K-k+1) * (n-k+1) / (k * (N-K-n+k)));
281 }
282 }
283 }
284
285
286 static float sum_probability(uint16_t K, uint16_t n, uint16_t k)
287 {
288 const uint16_t N = 256;
289
290 if (k > K || p_K[K] == 0.0) return 0.0;
291
292 double p_T_is_k_when_S_is_K = p_hypergeometric(N, K, n, k);
293 double p_S_is_K = p_K[K];
294 double p_T_is_k = 0;
295 for (uint16_t i = 0; i <= 256; i++) {
296 if (p_K[i] != 0.0) {
297 p_T_is_k += p_K[i] * p_hypergeometric(N, i, n, k);
298 }
299 }
300 return(p_T_is_k_when_S_is_K * p_S_is_K / p_T_is_k);
301 }
302
303
304
305
306 static inline uint_fast8_t common_bits(uint_fast8_t bytes_diff)
307 {
308 static const uint_fast8_t common_bits_LUT[256] = {
309 8, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
310 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
311 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
312 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
313 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
314 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
315 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
316 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
317 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
318 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
319 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
320 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
321 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
322 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
323 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
324 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
325 };
326
327 return common_bits_LUT[bytes_diff];
328 }
329
330
331 static void Tests()
332 {
333 // printf("Tests: Partial Statelist sizes\n");
334 // for (uint16_t i = 0; i <= 16; i+=2) {
335 // printf("Partial State List Odd [%2d] has %8d entries\n", i, partial_statelist[i].len[ODD_STATE]);
336 // }
337 // for (uint16_t i = 0; i <= 16; i+=2) {
338 // printf("Partial State List Even [%2d] has %8d entries\n", i, partial_statelist[i].len[EVEN_STATE]);
339 // }
340
341 // #define NUM_STATISTICS 100000
342 // uint32_t statistics_odd[17];
343 // uint64_t statistics[257];
344 // uint32_t statistics_even[17];
345 // struct Crypto1State cs;
346 // time_t time1 = clock();
347
348 // for (uint16_t i = 0; i < 257; i++) {
349 // statistics[i] = 0;
350 // }
351 // for (uint16_t i = 0; i < 17; i++) {
352 // statistics_odd[i] = 0;
353 // statistics_even[i] = 0;
354 // }
355
356 // for (uint64_t i = 0; i < NUM_STATISTICS; i++) {
357 // cs.odd = (rand() & 0xfff) << 12 | (rand() & 0xfff);
358 // cs.even = (rand() & 0xfff) << 12 | (rand() & 0xfff);
359 // uint16_t sum_property = SumProperty(&cs);
360 // statistics[sum_property] += 1;
361 // sum_property = PartialSumProperty(cs.even, EVEN_STATE);
362 // statistics_even[sum_property]++;
363 // sum_property = PartialSumProperty(cs.odd, ODD_STATE);
364 // statistics_odd[sum_property]++;
365 // if (i%(NUM_STATISTICS/100) == 0) printf(".");
366 // }
367
368 // 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);
369 // for (uint16_t i = 0; i < 257; i++) {
370 // if (statistics[i] != 0) {
371 // printf("probability[%3d] = %0.5f\n", i, (float)statistics[i]/NUM_STATISTICS);
372 // }
373 // }
374 // for (uint16_t i = 0; i <= 16; i++) {
375 // if (statistics_odd[i] != 0) {
376 // printf("probability odd [%2d] = %0.5f\n", i, (float)statistics_odd[i]/NUM_STATISTICS);
377 // }
378 // }
379 // for (uint16_t i = 0; i <= 16; i++) {
380 // if (statistics_odd[i] != 0) {
381 // printf("probability even [%2d] = %0.5f\n", i, (float)statistics_even[i]/NUM_STATISTICS);
382 // }
383 // }
384
385 // printf("Tests: Sum Probabilities based on Partial Sums\n");
386 // for (uint16_t i = 0; i < 257; i++) {
387 // statistics[i] = 0;
388 // }
389 // uint64_t num_states = 0;
390 // for (uint16_t oddsum = 0; oddsum <= 16; oddsum += 2) {
391 // for (uint16_t evensum = 0; evensum <= 16; evensum += 2) {
392 // uint16_t sum = oddsum*(16-evensum) + (16-oddsum)*evensum;
393 // statistics[sum] += (uint64_t)partial_statelist[oddsum].len[ODD_STATE] * partial_statelist[evensum].len[EVEN_STATE] * (1<<8);
394 // num_states += (uint64_t)partial_statelist[oddsum].len[ODD_STATE] * partial_statelist[evensum].len[EVEN_STATE] * (1<<8);
395 // }
396 // }
397 // printf("num_states = %lld, expected %lld\n", num_states, (1LL<<48));
398 // for (uint16_t i = 0; i < 257; i++) {
399 // if (statistics[i] != 0) {
400 // printf("probability[%3d] = %0.5f\n", i, (float)statistics[i]/num_states);
401 // }
402 // }
403
404 // printf("\nTests: Hypergeometric Probability for selected parameters\n");
405 // printf("p_hypergeometric(256, 206, 255, 206) = %0.8f\n", p_hypergeometric(256, 206, 255, 206));
406 // printf("p_hypergeometric(256, 206, 255, 205) = %0.8f\n", p_hypergeometric(256, 206, 255, 205));
407 // printf("p_hypergeometric(256, 156, 1, 1) = %0.8f\n", p_hypergeometric(256, 156, 1, 1));
408 // printf("p_hypergeometric(256, 156, 1, 0) = %0.8f\n", p_hypergeometric(256, 156, 1, 0));
409 // printf("p_hypergeometric(256, 1, 1, 1) = %0.8f\n", p_hypergeometric(256, 1, 1, 1));
410 // printf("p_hypergeometric(256, 1, 1, 0) = %0.8f\n", p_hypergeometric(256, 1, 1, 0));
411
412 // struct Crypto1State *pcs;
413 // pcs = crypto1_create(0xffffffffffff);
414 // printf("\nTests: for key = 0xffffffffffff:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
415 // SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
416 // crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
417 // printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
418 // best_first_bytes[0],
419 // SumProperty(pcs),
420 // pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
421 // //test_state_odd = pcs->odd & 0x00ffffff;
422 // //test_state_even = pcs->even & 0x00ffffff;
423 // crypto1_destroy(pcs);
424 // pcs = crypto1_create(0xa0a1a2a3a4a5);
425 // printf("Tests: for key = 0xa0a1a2a3a4a5:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
426 // SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
427 // crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
428 // printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
429 // best_first_bytes[0],
430 // SumProperty(pcs),
431 // pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
432 // //test_state_odd = pcs->odd & 0x00ffffff;
433 // //test_state_even = pcs->even & 0x00ffffff;
434 // crypto1_destroy(pcs);
435 // pcs = crypto1_create(0xa6b9aa97b955);
436 // printf("Tests: for key = 0xa6b9aa97b955:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
437 // SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
438 // crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
439 // printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n",
440 // best_first_bytes[0],
441 // SumProperty(pcs),
442 // pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff);
443 //test_state_odd = pcs->odd & 0x00ffffff;
444 //test_state_even = pcs->even & 0x00ffffff;
445 // crypto1_destroy(pcs);
446
447
448
449 // 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));
450
451 printf("\nTests: Actual BitFlipProperties odd/even:\n");
452 for (uint16_t i = 0; i < 256; i++) {
453 printf("[%02x]:%c ", i, nonces[i].BitFlip[ODD_STATE]?'o':nonces[i].BitFlip[EVEN_STATE]?'e':' ');
454 if (i % 8 == 7) {
455 printf("\n");
456 }
457 }
458
459 printf("\nTests: Sorted First Bytes:\n");
460 for (uint16_t i = 0; i < 256; i++) {
461 uint8_t best_byte = best_first_bytes[i];
462 printf("#%03d Byte: %02x, n = %3d, k = %3d, Sum(a8): %3d, Confidence: %5.1f%%, Bitflip: %c\n",
463 //printf("#%03d Byte: %02x, n = %3d, k = %3d, Sum(a8): %3d, Confidence: %5.1f%%, Bitflip: %c, score1: %1.5f, score2: %1.0f\n",
464 i, best_byte,
465 nonces[best_byte].num,
466 nonces[best_byte].Sum,
467 nonces[best_byte].Sum8_guess,
468 nonces[best_byte].Sum8_prob * 100,
469 nonces[best_byte].BitFlip[ODD_STATE]?'o':nonces[best_byte].BitFlip[EVEN_STATE]?'e':' '
470 //nonces[best_byte].score1,
471 //nonces[best_byte].score2
472 );
473 }
474
475 // printf("\nTests: parity performance\n");
476 // time_t time1p = clock();
477 // uint32_t par_sum = 0;
478 // for (uint32_t i = 0; i < 100000000; i++) {
479 // par_sum += parity(i);
480 // }
481 // printf("parsum oldparity = %d, time = %1.5fsec\n", par_sum, (float)(clock() - time1p)/CLOCKS_PER_SEC);
482
483 // time1p = clock();
484 // par_sum = 0;
485 // for (uint32_t i = 0; i < 100000000; i++) {
486 // par_sum += evenparity32(i);
487 // }
488 // printf("parsum newparity = %d, time = %1.5fsec\n", par_sum, (float)(clock() - time1p)/CLOCKS_PER_SEC);
489
490
491 }
492
493
494 static void sort_best_first_bytes(void)
495 {
496 // sort based on probability for correct guess
497 for (uint16_t i = 0; i < 256; i++ ) {
498 uint16_t j = 0;
499 float prob1 = nonces[i].Sum8_prob;
500 float prob2 = nonces[best_first_bytes[0]].Sum8_prob;
501 while (prob1 < prob2 && j < i) {
502 prob2 = nonces[best_first_bytes[++j]].Sum8_prob;
503 }
504 if (j < i) {
505 for (uint16_t k = i; k > j; k--) {
506 best_first_bytes[k] = best_first_bytes[k-1];
507 }
508 }
509 best_first_bytes[j] = i;
510 }
511
512 // determine how many are above the CONFIDENCE_THRESHOLD
513 uint16_t num_good_nonces = 0;
514 for (uint16_t i = 0; i < 256; i++) {
515 if (nonces[best_first_bytes[i]].Sum8_prob >= CONFIDENCE_THRESHOLD) {
516 ++num_good_nonces;
517 }
518 }
519
520 uint16_t best_first_byte = 0;
521
522 // select the best possible first byte based on number of common bits with all {b'}
523 // uint16_t max_common_bits = 0;
524 // for (uint16_t i = 0; i < num_good_nonces; i++) {
525 // uint16_t sum_common_bits = 0;
526 // for (uint16_t j = 0; j < num_good_nonces; j++) {
527 // if (i != j) {
528 // sum_common_bits += common_bits(best_first_bytes[i],best_first_bytes[j]);
529 // }
530 // }
531 // if (sum_common_bits > max_common_bits) {
532 // max_common_bits = sum_common_bits;
533 // best_first_byte = i;
534 // }
535 // }
536
537 // select best possible first byte {b} based on least likely sum/bitflip property
538 float min_p_K = 1.0;
539 for (uint16_t i = 0; i < num_good_nonces; i++ ) {
540 uint16_t sum8 = nonces[best_first_bytes[i]].Sum8_guess;
541 float bitflip_prob = 1.0;
542 if (nonces[best_first_bytes[i]].BitFlip[ODD_STATE] || nonces[best_first_bytes[i]].BitFlip[EVEN_STATE]) {
543 bitflip_prob = 0.09375;
544 }
545 nonces[best_first_bytes[i]].score1 = p_K[sum8] * bitflip_prob;
546 if (p_K[sum8] * bitflip_prob <= min_p_K) {
547 min_p_K = p_K[sum8] * bitflip_prob;
548 }
549 }
550
551
552 // use number of commmon bits as a tie breaker
553 uint16_t max_common_bits = 0;
554 for (uint16_t i = 0; i < num_good_nonces; i++) {
555 float bitflip_prob = 1.0;
556 if (nonces[best_first_bytes[i]].BitFlip[ODD_STATE] || nonces[best_first_bytes[i]].BitFlip[EVEN_STATE]) {
557 bitflip_prob = 0.09375;
558 }
559 if (p_K[nonces[best_first_bytes[i]].Sum8_guess] * bitflip_prob == min_p_K) {
560 uint16_t sum_common_bits = 0;
561 for (uint16_t j = 0; j < num_good_nonces; j++) {
562 sum_common_bits += common_bits(best_first_bytes[i] ^ best_first_bytes[j]);
563 }
564 nonces[best_first_bytes[i]].score2 = sum_common_bits;
565 if (sum_common_bits > max_common_bits) {
566 max_common_bits = sum_common_bits;
567 best_first_byte = i;
568 }
569 }
570 }
571
572 // swap best possible first byte to the pole position
573 uint16_t temp = best_first_bytes[0];
574 best_first_bytes[0] = best_first_bytes[best_first_byte];
575 best_first_bytes[best_first_byte] = temp;
576
577 }
578
579
580 static uint16_t estimate_second_byte_sum(void)
581 {
582
583 for (uint16_t first_byte = 0; first_byte < 256; first_byte++) {
584 float Sum8_prob = 0.0;
585 uint16_t Sum8 = 0;
586 if (nonces[first_byte].updated) {
587 for (uint16_t sum = 0; sum <= 256; sum++) {
588 float prob = sum_probability(sum, nonces[first_byte].num, nonces[first_byte].Sum);
589 if (prob > Sum8_prob) {
590 Sum8_prob = prob;
591 Sum8 = sum;
592 }
593 }
594 nonces[first_byte].Sum8_guess = Sum8;
595 nonces[first_byte].Sum8_prob = Sum8_prob;
596 nonces[first_byte].updated = false;
597 }
598 }
599
600 sort_best_first_bytes();
601
602 uint16_t num_good_nonces = 0;
603 for (uint16_t i = 0; i < 256; i++) {
604 if (nonces[best_first_bytes[i]].Sum8_prob >= CONFIDENCE_THRESHOLD) {
605 ++num_good_nonces;
606 }
607 }
608
609 return num_good_nonces;
610 }
611
612
613 static int read_nonce_file(void)
614 {
615 FILE *fnonces = NULL;
616 uint8_t trgBlockNo;
617 uint8_t trgKeyType;
618 uint8_t read_buf[9];
619 uint32_t nt_enc1, nt_enc2;
620 uint8_t par_enc;
621 int total_num_nonces = 0;
622
623 if ((fnonces = fopen("nonces.bin","rb")) == NULL) {
624 PrintAndLog("Could not open file nonces.bin");
625 return 1;
626 }
627
628 PrintAndLog("Reading nonces from file nonces.bin...");
629 size_t bytes_read = fread(read_buf, 1, 6, fnonces);
630 if ( bytes_read == 0) {
631 PrintAndLog("File reading error.");
632 fclose(fnonces);
633 return 1;
634 }
635 cuid = bytes_to_num(read_buf, 4);
636 trgBlockNo = bytes_to_num(read_buf+4, 1);
637 trgKeyType = bytes_to_num(read_buf+5, 1);
638
639 while (fread(read_buf, 1, 9, fnonces) == 9) {
640 nt_enc1 = bytes_to_num(read_buf, 4);
641 nt_enc2 = bytes_to_num(read_buf+4, 4);
642 par_enc = bytes_to_num(read_buf+8, 1);
643 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4);
644 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f);
645 add_nonce(nt_enc1, par_enc >> 4);
646 add_nonce(nt_enc2, par_enc & 0x0f);
647 total_num_nonces += 2;
648 }
649 fclose(fnonces);
650 PrintAndLog("Read %d nonces from file. cuid=%08x, Block=%d, Keytype=%c", total_num_nonces, cuid, trgBlockNo, trgKeyType==0?'A':'B');
651
652 return 0;
653 }
654
655
656 static void Check_for_FilterFlipProperties(void)
657 {
658 printf("Checking for Filter Flip Properties...\n");
659
660 uint16_t num_bitflips = 0;
661
662 for (uint16_t i = 0; i < 256; i++) {
663 nonces[i].BitFlip[ODD_STATE] = false;
664 nonces[i].BitFlip[EVEN_STATE] = false;
665 }
666
667 for (uint16_t i = 0; i < 256; i++) {
668 uint8_t parity1 = (nonces[i].first->par_enc) >> 3; // parity of first byte
669 uint8_t parity2_odd = (nonces[i^0x80].first->par_enc) >> 3; // XOR 0x80 = last bit flipped
670 uint8_t parity2_even = (nonces[i^0x40].first->par_enc) >> 3; // XOR 0x40 = second last bit flipped
671
672 if (parity1 == parity2_odd) { // has Bit Flip Property for odd bits
673 nonces[i].BitFlip[ODD_STATE] = true;
674 num_bitflips++;
675 } else if (parity1 == parity2_even) { // has Bit Flip Property for even bits
676 nonces[i].BitFlip[EVEN_STATE] = true;
677 num_bitflips++;
678 }
679 }
680
681 if (write_stats) {
682 fprintf(fstats, "%d;", num_bitflips);
683 }
684 }
685
686
687 static void simulate_MFplus_RNG(uint32_t test_cuid, uint64_t test_key, uint32_t *nt_enc, uint8_t *par_enc)
688 {
689 struct Crypto1State sim_cs;
690 sim_cs.odd = sim_cs.even = 0;
691
692 // init cryptostate with key:
693 for(int8_t i = 47; i > 0; i -= 2) {
694 sim_cs.odd = sim_cs.odd << 1 | BIT(test_key, (i - 1) ^ 7);
695 sim_cs.even = sim_cs.even << 1 | BIT(test_key, i ^ 7);
696 }
697
698 *par_enc = 0;
699 uint32_t nt = (rand() & 0xff) << 24 | (rand() & 0xff) << 16 | (rand() & 0xff) << 8 | (rand() & 0xff);
700 for (int8_t byte_pos = 3; byte_pos >= 0; byte_pos--) {
701 uint8_t nt_byte_dec = (nt >> (8*byte_pos)) & 0xff;
702 uint8_t nt_byte_enc = crypto1_byte(&sim_cs, nt_byte_dec ^ (test_cuid >> (8*byte_pos)), false) ^ nt_byte_dec; // encode the nonce byte
703 *nt_enc = (*nt_enc << 8) | nt_byte_enc;
704 uint8_t ks_par = filter(sim_cs.odd); // the keystream bit to encode/decode the parity bit
705 uint8_t nt_byte_par_enc = ks_par ^ oddparity8(nt_byte_dec); // determine the nt byte's parity and encode it
706 *par_enc = (*par_enc << 1) | nt_byte_par_enc;
707 }
708
709 }
710
711
712 static void simulate_acquire_nonces()
713 {
714 clock_t time1 = clock();
715 bool filter_flip_checked = false;
716 uint32_t total_num_nonces = 0;
717 uint32_t next_fivehundred = 500;
718 uint32_t total_added_nonces = 0;
719
720 cuid = (rand() & 0xff) << 24 | (rand() & 0xff) << 16 | (rand() & 0xff) << 8 | (rand() & 0xff);
721 known_target_key = ((uint64_t)rand() & 0xfff) << 36 | ((uint64_t)rand() & 0xfff) << 24 | ((uint64_t)rand() & 0xfff) << 12 | ((uint64_t)rand() & 0xfff);
722
723 printf("Simulating nonce acquisition for target key %012"llx", cuid %08x ...\n", known_target_key, cuid);
724 fprintf(fstats, "%012"llx";%08x;", known_target_key, cuid);
725
726 do {
727 uint32_t nt_enc = 0;
728 uint8_t par_enc = 0;
729
730 simulate_MFplus_RNG(cuid, known_target_key, &nt_enc, &par_enc);
731 //printf("Simulated RNG: nt_enc1: %08x, nt_enc2: %08x, par_enc: %02x\n", nt_enc1, nt_enc2, par_enc);
732 total_added_nonces += add_nonce(nt_enc, par_enc);
733 total_num_nonces++;
734
735 if (first_byte_num == 256 ) {
736 // printf("first_byte_num = %d, first_byte_Sum = %d\n", first_byte_num, first_byte_Sum);
737 if (!filter_flip_checked) {
738 Check_for_FilterFlipProperties();
739 filter_flip_checked = true;
740 }
741 num_good_first_bytes = estimate_second_byte_sum();
742 if (total_num_nonces > next_fivehundred) {
743 next_fivehundred = (total_num_nonces/500+1) * 500;
744 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",
745 total_num_nonces,
746 total_added_nonces,
747 CONFIDENCE_THRESHOLD * 100.0,
748 num_good_first_bytes);
749 }
750 }
751
752 } while (num_good_first_bytes < GOOD_BYTES_REQUIRED);
753
754 time1 = clock() - time1;
755 if ( time1 > 0 ) {
756 PrintAndLog("Acquired a total of %d nonces in %1.1f seconds (%0.0f nonces/minute)",
757 total_num_nonces,
758 ((float)time1)/CLOCKS_PER_SEC,
759 total_num_nonces * 60.0 * CLOCKS_PER_SEC/(float)time1);
760 }
761 fprintf(fstats, "%d;%d;%d;%1.2f;", total_num_nonces, total_added_nonces, num_good_first_bytes, CONFIDENCE_THRESHOLD);
762
763 }
764
765
766 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)
767 {
768 clock_t time1 = clock();
769 bool initialize = true;
770 bool field_off = false;
771 bool finished = false;
772 bool filter_flip_checked = false;
773 uint32_t flags = 0;
774 uint8_t write_buf[9];
775 uint32_t total_num_nonces = 0;
776 uint32_t next_fivehundred = 500;
777 uint32_t total_added_nonces = 0;
778 FILE *fnonces = NULL;
779 UsbCommand resp;
780
781 printf("Acquiring nonces...\n");
782
783 clearCommandBuffer();
784
785 do {
786 flags = 0;
787 flags |= initialize ? 0x0001 : 0;
788 flags |= slow ? 0x0002 : 0;
789 flags |= field_off ? 0x0004 : 0;
790 UsbCommand c = {CMD_MIFARE_ACQUIRE_ENCRYPTED_NONCES, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, flags}};
791 memcpy(c.d.asBytes, key, 6);
792
793 SendCommand(&c);
794
795 if (field_off) finished = true;
796
797 if (initialize) {
798 if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) return 1;
799 if (resp.arg[0]) return resp.arg[0]; // error during nested_hard
800
801 cuid = resp.arg[1];
802 // PrintAndLog("Acquiring nonces for CUID 0x%08x", cuid);
803 if (nonce_file_write && fnonces == NULL) {
804 if ((fnonces = fopen("nonces.bin","wb")) == NULL) {
805 PrintAndLog("Could not create file nonces.bin");
806 return 3;
807 }
808 PrintAndLog("Writing acquired nonces to binary file nonces.bin");
809 num_to_bytes(cuid, 4, write_buf);
810 fwrite(write_buf, 1, 4, fnonces);
811 fwrite(&trgBlockNo, 1, 1, fnonces);
812 fwrite(&trgKeyType, 1, 1, fnonces);
813 }
814 }
815
816 if (!initialize) {
817 uint32_t nt_enc1, nt_enc2;
818 uint8_t par_enc;
819 uint16_t num_acquired_nonces = resp.arg[2];
820 uint8_t *bufp = resp.d.asBytes;
821 for (uint16_t i = 0; i < num_acquired_nonces; i+=2) {
822 nt_enc1 = bytes_to_num(bufp, 4);
823 nt_enc2 = bytes_to_num(bufp+4, 4);
824 par_enc = bytes_to_num(bufp+8, 1);
825
826 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4);
827 total_added_nonces += add_nonce(nt_enc1, par_enc >> 4);
828 //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f);
829 total_added_nonces += add_nonce(nt_enc2, par_enc & 0x0f);
830
831
832 if (nonce_file_write) {
833 fwrite(bufp, 1, 9, fnonces);
834 }
835
836 bufp += 9;
837 }
838
839 total_num_nonces += num_acquired_nonces;
840 }
841
842 if (first_byte_num == 256 ) {
843 // printf("first_byte_num = %d, first_byte_Sum = %d\n", first_byte_num, first_byte_Sum);
844 if (!filter_flip_checked) {
845 Check_for_FilterFlipProperties();
846 filter_flip_checked = true;
847 }
848 num_good_first_bytes = estimate_second_byte_sum();
849 if (total_num_nonces > next_fivehundred) {
850 next_fivehundred = (total_num_nonces/500+1) * 500;
851 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",
852 total_num_nonces,
853 total_added_nonces,
854 CONFIDENCE_THRESHOLD * 100.0,
855 num_good_first_bytes);
856 }
857 if (num_good_first_bytes >= GOOD_BYTES_REQUIRED) {
858 field_off = true; // switch off field with next SendCommand and then finish
859 }
860 }
861
862 if (!initialize) {
863 if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) {
864 fclose(fnonces);
865 return 1;
866 }
867 if (resp.arg[0]) {
868 fclose(fnonces);
869 return resp.arg[0]; // error during nested_hard
870 }
871 }
872
873 initialize = false;
874
875 } while (!finished);
876
877
878 if (nonce_file_write) {
879 fclose(fnonces);
880 }
881
882 time1 = clock() - time1;
883 if ( time1 > 0 ) {
884 PrintAndLog("Acquired a total of %d nonces in %1.1f seconds (%0.0f nonces/minute)",
885 total_num_nonces,
886 ((float)time1)/CLOCKS_PER_SEC,
887 total_num_nonces * 60.0 * CLOCKS_PER_SEC/(float)time1
888 );
889 }
890 return 0;
891 }
892
893
894 static int init_partial_statelists(void)
895 {
896 const uint32_t sizes_odd[17] = { 126757, 0, 18387, 0, 74241, 0, 181737, 0, 248801, 0, 182033, 0, 73421, 0, 17607, 0, 125601 };
897 const uint32_t sizes_even[17] = { 125723, 0, 17867, 0, 74305, 0, 178707, 0, 248801, 0, 185063, 0, 73356, 0, 18127, 0, 126634 };
898
899 printf("Allocating memory for partial statelists...\n");
900 for (odd_even_t odd_even = EVEN_STATE; odd_even <= ODD_STATE; odd_even++) {
901 for (uint16_t i = 0; i <= 16; i+=2) {
902 partial_statelist[i].len[odd_even] = 0;
903 uint32_t num_of_states = odd_even == ODD_STATE ? sizes_odd[i] : sizes_even[i];
904 partial_statelist[i].states[odd_even] = malloc(sizeof(uint32_t) * num_of_states);
905 if (partial_statelist[i].states[odd_even] == NULL) {
906 PrintAndLog("Cannot allocate enough memory. Aborting");
907 return 4;
908 }
909 for (uint32_t j = 0; j < STATELIST_INDEX_SIZE; j++) {
910 partial_statelist[i].index[odd_even][j] = NULL;
911 }
912 }
913 }
914
915 printf("Generating partial statelists...\n");
916 for (odd_even_t odd_even = EVEN_STATE; odd_even <= ODD_STATE; odd_even++) {
917 uint32_t index = -1;
918 uint32_t num_of_states = 1<<20;
919 for (uint32_t state = 0; state < num_of_states; state++) {
920 uint16_t sum_property = PartialSumProperty(state, odd_even);
921 uint32_t *p = partial_statelist[sum_property].states[odd_even];
922 p += partial_statelist[sum_property].len[odd_even];
923 *p = state;
924 partial_statelist[sum_property].len[odd_even]++;
925 uint32_t index_mask = (STATELIST_INDEX_SIZE-1) << (20-STATELIST_INDEX_WIDTH);
926 if ((state & index_mask) != index) {
927 index = state & index_mask;
928 }
929 if (partial_statelist[sum_property].index[odd_even][index >> (20-STATELIST_INDEX_WIDTH)] == NULL) {
930 partial_statelist[sum_property].index[odd_even][index >> (20-STATELIST_INDEX_WIDTH)] = p;
931 }
932 }
933 // add End Of List markers
934 for (uint16_t i = 0; i <= 16; i += 2) {
935 uint32_t *p = partial_statelist[i].states[odd_even];
936 p += partial_statelist[i].len[odd_even];
937 *p = 0xffffffff;
938 }
939 }
940
941 return 0;
942 }
943
944
945 static void init_BitFlip_statelist(void)
946 {
947 printf("Generating bitflip statelist...\n");
948 uint32_t *p = statelist_bitflip.states[0] = malloc(sizeof(uint32_t) * 1<<20);
949 uint32_t index = -1;
950 uint32_t index_mask = (STATELIST_INDEX_SIZE-1) << (20-STATELIST_INDEX_WIDTH);
951 for (uint32_t state = 0; state < (1 << 20); state++) {
952 if (filter(state) != filter(state^1)) {
953 if ((state & index_mask) != index) {
954 index = state & index_mask;
955 }
956 if (statelist_bitflip.index[0][index >> (20-STATELIST_INDEX_WIDTH)] == NULL) {
957 statelist_bitflip.index[0][index >> (20-STATELIST_INDEX_WIDTH)] = p;
958 }
959 *p++ = state;
960 }
961 }
962 // set len and add End Of List marker
963 statelist_bitflip.len[0] = p - statelist_bitflip.states[0];
964 *p = 0xffffffff;
965 statelist_bitflip.states[0] = realloc(statelist_bitflip.states[0], sizeof(uint32_t) * (statelist_bitflip.len[0] + 1));
966 }
967
968
969 static inline uint32_t *find_first_state(uint32_t state, uint32_t mask, partial_indexed_statelist_t *sl, odd_even_t odd_even)
970 {
971 uint32_t *p = sl->index[odd_even][(state & mask) >> (20-STATELIST_INDEX_WIDTH)]; // first Bits as index
972
973 if (p == NULL) return NULL;
974 while (*p < (state & mask)) p++;
975 if (*p == 0xffffffff) return NULL; // reached end of list, no match
976 if ((*p & mask) == (state & mask)) return p; // found a match.
977 return NULL; // no match
978 }
979
980
981 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)
982 {
983 uint_fast8_t j_1_bit_mask = 0x01 << (bit-1);
984 uint_fast8_t bit_diff = byte_diff & j_1_bit_mask; // difference of (j-1)th bit
985 uint_fast8_t filter_diff = filter(state1 >> (4-state_bit)) ^ filter(state2 >> (4-state_bit)); // difference in filter function
986 uint_fast8_t mask_y12_y13 = 0xc0 >> state_bit;
987 uint_fast8_t state_bits_diff = (state1 ^ state2) & mask_y12_y13; // difference in state bits 12 and 13
988 uint_fast8_t all_diff = evenparity8(bit_diff ^ state_bits_diff ^ filter_diff); // use parity function to XOR all bits
989 return !all_diff;
990 }
991
992
993 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)
994 {
995 uint_fast8_t j_bit_mask = 0x01 << bit;
996 uint_fast8_t bit_diff = byte_diff & j_bit_mask; // difference of jth bit
997 uint_fast8_t mask_y13_y16 = 0x48 >> state_bit;
998 uint_fast8_t state_bits_diff = (state1 ^ state2) & mask_y13_y16; // difference in state bits 13 and 16
999 uint_fast8_t all_diff = evenparity8(bit_diff ^ state_bits_diff); // use parity function to XOR all bits
1000 return all_diff;
1001 }
1002
1003
1004 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)
1005 {
1006 if (odd_even) {
1007 // odd bits
1008 switch (num_common_bits) {
1009 case 0: if (!invariant_holds(byte_diff, state1, state2, 1, 0)) return true;
1010 case 1: if (invalid_state(byte_diff, state1, state2, 1, 0)) return false;
1011 case 2: if (!invariant_holds(byte_diff, state1, state2, 3, 1)) return true;
1012 case 3: if (invalid_state(byte_diff, state1, state2, 3, 1)) return false;
1013 case 4: if (!invariant_holds(byte_diff, state1, state2, 5, 2)) return true;
1014 case 5: if (invalid_state(byte_diff, state1, state2, 5, 2)) return false;
1015 case 6: if (!invariant_holds(byte_diff, state1, state2, 7, 3)) return true;
1016 case 7: if (invalid_state(byte_diff, state1, state2, 7, 3)) return false;
1017 }
1018 } else {
1019 // even bits
1020 switch (num_common_bits) {
1021 case 0: if (invalid_state(byte_diff, state1, state2, 0, 0)) return false;
1022 case 1: if (!invariant_holds(byte_diff, state1, state2, 2, 1)) return true;
1023 case 2: if (invalid_state(byte_diff, state1, state2, 2, 1)) return false;
1024 case 3: if (!invariant_holds(byte_diff, state1, state2, 4, 2)) return true;
1025 case 4: if (invalid_state(byte_diff, state1, state2, 4, 2)) return false;
1026 case 5: if (!invariant_holds(byte_diff, state1, state2, 6, 3)) return true;
1027 case 6: if (invalid_state(byte_diff, state1, state2, 6, 3)) return false;
1028 }
1029 }
1030
1031 return true; // valid state
1032 }
1033
1034
1035 static bool all_other_first_bytes_match(uint32_t state, odd_even_t odd_even)
1036 {
1037 for (uint16_t i = 1; i < num_good_first_bytes; i++) {
1038 uint16_t sum_a8 = nonces[best_first_bytes[i]].Sum8_guess;
1039 uint_fast8_t bytes_diff = best_first_bytes[0] ^ best_first_bytes[i];
1040 uint_fast8_t j = common_bits(bytes_diff);
1041 uint32_t mask = 0xfffffff0;
1042 if (odd_even == ODD_STATE) {
1043 mask >>= j/2;
1044 } else {
1045 mask >>= (j+1)/2;
1046 }
1047 mask &= 0x000fffff;
1048 //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);
1049 bool found_match = false;
1050 for (uint16_t r = 0; r <= 16 && !found_match; r += 2) {
1051 for (uint16_t s = 0; s <= 16 && !found_match; s += 2) {
1052 if (r*(16-s) + (16-r)*s == sum_a8) {
1053 //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);
1054 uint16_t part_sum_a8 = (odd_even == ODD_STATE) ? r : s;
1055 uint32_t *p = find_first_state(state, mask, &partial_statelist[part_sum_a8], odd_even);
1056 if (p != NULL) {
1057 while ((state & mask) == (*p & mask) && (*p != 0xffffffff)) {
1058 if (remaining_bits_match(j, bytes_diff, state, (state&0x00fffff0) | *p, odd_even)) {
1059 found_match = true;
1060 // if ((odd_even == ODD_STATE && state == test_state_odd)
1061 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1062 // 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",
1063 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1064 // }
1065 break;
1066 } else {
1067 // if ((odd_even == ODD_STATE && state == test_state_odd)
1068 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1069 // 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",
1070 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1071 // }
1072 }
1073 p++;
1074 }
1075 } else {
1076 // if ((odd_even == ODD_STATE && state == test_state_odd)
1077 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1078 // 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",
1079 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1080 // }
1081 }
1082 }
1083 }
1084 }
1085
1086 if (!found_match) {
1087 // if ((odd_even == ODD_STATE && state == test_state_odd)
1088 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1089 // 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);
1090 // }
1091 return false;
1092 }
1093 }
1094
1095 return true;
1096 }
1097
1098
1099 static bool all_bit_flips_match(uint32_t state, odd_even_t odd_even)
1100 {
1101 for (uint16_t i = 0; i < 256; i++) {
1102 if (nonces[i].BitFlip[odd_even] && i != best_first_bytes[0]) {
1103 uint_fast8_t bytes_diff = best_first_bytes[0] ^ i;
1104 uint_fast8_t j = common_bits(bytes_diff);
1105 uint32_t mask = 0xfffffff0;
1106 if (odd_even == ODD_STATE) {
1107 mask >>= j/2;
1108 } else {
1109 mask >>= (j+1)/2;
1110 }
1111 mask &= 0x000fffff;
1112 //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);
1113 bool found_match = false;
1114 uint32_t *p = find_first_state(state, mask, &statelist_bitflip, 0);
1115 if (p != NULL) {
1116 while ((state & mask) == (*p & mask) && (*p != 0xffffffff)) {
1117 if (remaining_bits_match(j, bytes_diff, state, (state&0x00fffff0) | *p, odd_even)) {
1118 found_match = true;
1119 // if ((odd_even == ODD_STATE && state == test_state_odd)
1120 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1121 // 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",
1122 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1123 // }
1124 break;
1125 } else {
1126 // if ((odd_even == ODD_STATE && state == test_state_odd)
1127 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1128 // 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",
1129 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1130 // }
1131 }
1132 p++;
1133 }
1134 } else {
1135 // if ((odd_even == ODD_STATE && state == test_state_odd)
1136 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1137 // 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",
1138 // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8);
1139 // }
1140 }
1141 if (!found_match) {
1142 // if ((odd_even == ODD_STATE && state == test_state_odd)
1143 // || (odd_even == EVEN_STATE && state == test_state_even)) {
1144 // 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);
1145 // }
1146 return false;
1147 }
1148 }
1149
1150 }
1151
1152 return true;
1153 }
1154
1155
1156 static struct sl_cache_entry {
1157 uint32_t *sl;
1158 uint32_t len;
1159 } sl_cache[17][17][2];
1160
1161
1162 static void init_statelist_cache(void)
1163 {
1164 for (uint16_t i = 0; i < 17; i+=2) {
1165 for (uint16_t j = 0; j < 17; j+=2) {
1166 for (uint16_t k = 0; k < 2; k++) {
1167 sl_cache[i][j][k].sl = NULL;
1168 sl_cache[i][j][k].len = 0;
1169 }
1170 }
1171 }
1172 }
1173
1174
1175 static int add_matching_states(statelist_t *candidates, uint16_t part_sum_a0, uint16_t part_sum_a8, odd_even_t odd_even)
1176 {
1177 uint32_t worstcase_size = 1<<20;
1178
1179 // check cache for existing results
1180 if (sl_cache[part_sum_a0][part_sum_a8][odd_even].sl != NULL) {
1181 candidates->states[odd_even] = sl_cache[part_sum_a0][part_sum_a8][odd_even].sl;
1182 candidates->len[odd_even] = sl_cache[part_sum_a0][part_sum_a8][odd_even].len;
1183 return 0;
1184 }
1185
1186 candidates->states[odd_even] = (uint32_t *)malloc(sizeof(uint32_t) * worstcase_size);
1187 if (candidates->states[odd_even] == NULL) {
1188 PrintAndLog("Out of memory error.\n");
1189 return 4;
1190 }
1191 uint32_t *add_p = candidates->states[odd_even];
1192 for (uint32_t *p1 = partial_statelist[part_sum_a0].states[odd_even]; *p1 != 0xffffffff; p1++) {
1193 uint32_t search_mask = 0x000ffff0;
1194 uint32_t *p2 = find_first_state((*p1 << 4), search_mask, &partial_statelist[part_sum_a8], odd_even);
1195 if (p2 != NULL) {
1196 while (((*p1 << 4) & search_mask) == (*p2 & search_mask) && *p2 != 0xffffffff) {
1197 if ((nonces[best_first_bytes[0]].BitFlip[odd_even] && find_first_state((*p1 << 4) | *p2, 0x000fffff, &statelist_bitflip, 0))
1198 || !nonces[best_first_bytes[0]].BitFlip[odd_even]) {
1199 if (all_other_first_bytes_match((*p1 << 4) | *p2, odd_even)) {
1200 if (all_bit_flips_match((*p1 << 4) | *p2, odd_even)) {
1201 *add_p++ = (*p1 << 4) | *p2;
1202 }
1203 }
1204 }
1205 p2++;
1206 }
1207 }
1208 }
1209
1210 // set end of list marker and len
1211 *add_p = 0xffffffff;
1212 candidates->len[odd_even] = add_p - candidates->states[odd_even];
1213
1214 candidates->states[odd_even] = realloc(candidates->states[odd_even], sizeof(uint32_t) * (candidates->len[odd_even] + 1));
1215
1216 sl_cache[part_sum_a0][part_sum_a8][odd_even].sl = candidates->states[odd_even];
1217 sl_cache[part_sum_a0][part_sum_a8][odd_even].len = candidates->len[odd_even];
1218
1219 return 0;
1220 }
1221
1222
1223 static statelist_t *add_more_candidates(statelist_t *current_candidates)
1224 {
1225 statelist_t *new_candidates = NULL;
1226 if (current_candidates == NULL) {
1227 if (candidates == NULL) {
1228 candidates = (statelist_t *)malloc(sizeof(statelist_t));
1229 }
1230 new_candidates = candidates;
1231 } else {
1232 new_candidates = current_candidates->next = (statelist_t *)malloc(sizeof(statelist_t));
1233 }
1234 new_candidates->next = NULL;
1235 new_candidates->len[ODD_STATE] = 0;
1236 new_candidates->len[EVEN_STATE] = 0;
1237 new_candidates->states[ODD_STATE] = NULL;
1238 new_candidates->states[EVEN_STATE] = NULL;
1239 return new_candidates;
1240 }
1241
1242
1243 static void TestIfKeyExists(uint64_t key)
1244 {
1245 struct Crypto1State *pcs;
1246 pcs = crypto1_create(key);
1247 crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true);
1248
1249 uint32_t state_odd = pcs->odd & 0x00ffffff;
1250 uint32_t state_even = pcs->even & 0x00ffffff;
1251 //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);
1252
1253 uint64_t count = 0;
1254 for (statelist_t *p = candidates; p != NULL; p = p->next) {
1255 bool found_odd = false;
1256 bool found_even = false;
1257 uint32_t *p_odd = p->states[ODD_STATE];
1258 uint32_t *p_even = p->states[EVEN_STATE];
1259 while (*p_odd != 0xffffffff) {
1260 if ((*p_odd & 0x00ffffff) == state_odd) {
1261 found_odd = true;
1262 break;
1263 }
1264 p_odd++;
1265 }
1266 while (*p_even != 0xffffffff) {
1267 if ((*p_even & 0x00ffffff) == state_even) {
1268 found_even = true;
1269 }
1270 p_even++;
1271 }
1272 count += (p_odd - p->states[ODD_STATE]) * (p_even - p->states[EVEN_STATE]);
1273 if (found_odd && found_even) {
1274 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.",
1275 count, log(count)/log(2),
1276 maximum_states, log(maximum_states)/log(2),
1277 (count>>23)/60);
1278 if (write_stats) {
1279 fprintf(fstats, "1\n");
1280 }
1281 crypto1_destroy(pcs);
1282 return;
1283 }
1284 }
1285
1286 printf("Key NOT found!\n");
1287 if (write_stats) {
1288 fprintf(fstats, "0\n");
1289 }
1290 crypto1_destroy(pcs);
1291 }
1292
1293
1294 static void generate_candidates(uint16_t sum_a0, uint16_t sum_a8)
1295 {
1296 printf("Generating crypto1 state candidates... \n");
1297
1298 statelist_t *current_candidates = NULL;
1299 // estimate maximum candidate states
1300 maximum_states = 0;
1301 for (uint16_t sum_odd = 0; sum_odd <= 16; sum_odd += 2) {
1302 for (uint16_t sum_even = 0; sum_even <= 16; sum_even += 2) {
1303 if (sum_odd*(16-sum_even) + (16-sum_odd)*sum_even == sum_a0) {
1304 maximum_states += (uint64_t)partial_statelist[sum_odd].len[ODD_STATE] * partial_statelist[sum_even].len[EVEN_STATE] * (1<<8);
1305 }
1306 }
1307 }
1308 printf("Number of possible keys with Sum(a0) = %d: %"PRIu64" (2^%1.1f)\n", sum_a0, maximum_states, log(maximum_states)/log(2.0));
1309
1310 init_statelist_cache();
1311
1312 for (uint16_t p = 0; p <= 16; p += 2) {
1313 for (uint16_t q = 0; q <= 16; q += 2) {
1314 if (p*(16-q) + (16-p)*q == sum_a0) {
1315 printf("Reducing Partial Statelists (p,q) = (%d,%d) with lengths %d, %d\n",
1316 p, q, partial_statelist[p].len[ODD_STATE], partial_statelist[q].len[EVEN_STATE]);
1317 for (uint16_t r = 0; r <= 16; r += 2) {
1318 for (uint16_t s = 0; s <= 16; s += 2) {
1319 if (r*(16-s) + (16-r)*s == sum_a8) {
1320 current_candidates = add_more_candidates(current_candidates);
1321 // check for the smallest partial statelist. Try this first - it might give 0 candidates
1322 // and eliminate the need to calculate the other part
1323 if (MIN(partial_statelist[p].len[ODD_STATE], partial_statelist[r].len[ODD_STATE])
1324 < MIN(partial_statelist[q].len[EVEN_STATE], partial_statelist[s].len[EVEN_STATE])) {
1325 add_matching_states(current_candidates, p, r, ODD_STATE);
1326 if(current_candidates->len[ODD_STATE]) {
1327 add_matching_states(current_candidates, q, s, EVEN_STATE);
1328 } else {
1329 current_candidates->len[EVEN_STATE] = 0;
1330 uint32_t *p = current_candidates->states[EVEN_STATE] = malloc(sizeof(uint32_t));
1331 *p = 0xffffffff;
1332 }
1333 } else {
1334 add_matching_states(current_candidates, q, s, EVEN_STATE);
1335 if(current_candidates->len[EVEN_STATE]) {
1336 add_matching_states(current_candidates, p, r, ODD_STATE);
1337 } else {
1338 current_candidates->len[ODD_STATE] = 0;
1339 uint32_t *p = current_candidates->states[ODD_STATE] = malloc(sizeof(uint32_t));
1340 *p = 0xffffffff;
1341 }
1342 }
1343 printf("Odd state candidates: %6d (2^%0.1f)\n", current_candidates->len[ODD_STATE], log(current_candidates->len[ODD_STATE])/log(2));
1344 printf("Even state candidates: %6d (2^%0.1f)\n", current_candidates->len[EVEN_STATE], log(current_candidates->len[EVEN_STATE])/log(2));
1345 }
1346 }
1347 }
1348 }
1349 }
1350 }
1351
1352
1353 maximum_states = 0;
1354 for (statelist_t *sl = candidates; sl != NULL; sl = sl->next) {
1355 maximum_states += (uint64_t)sl->len[ODD_STATE] * sl->len[EVEN_STATE];
1356 }
1357 printf("Number of remaining possible keys: %"PRIu64" (2^%1.1f)\n", maximum_states, log(maximum_states)/log(2.0));
1358 if (write_stats) {
1359 if (maximum_states != 0) {
1360 fprintf(fstats, "%1.1f;", log(maximum_states)/log(2.0));
1361 } else {
1362 fprintf(fstats, "%1.1f;", 0.0);
1363 }
1364 }
1365 }
1366
1367
1368 static void free_candidates_memory(statelist_t *sl)
1369 {
1370 if (sl == NULL) {
1371 return;
1372 } else {
1373 free_candidates_memory(sl->next);
1374 free(sl);
1375 }
1376 }
1377
1378
1379 static void free_statelist_cache(void)
1380 {
1381 for (uint16_t i = 0; i < 17; i+=2) {
1382 for (uint16_t j = 0; j < 17; j+=2) {
1383 for (uint16_t k = 0; k < 2; k++) {
1384 free(sl_cache[i][j][k].sl);
1385 }
1386 }
1387 }
1388 }
1389
1390
1391 static void brute_force(void)
1392 {
1393 if (known_target_key != -1) {
1394 PrintAndLog("Looking for known target key in remaining key space...");
1395 TestIfKeyExists(known_target_key);
1396 } else {
1397 PrintAndLog("Brute Force phase is not implemented.");
1398 }
1399
1400 }
1401
1402
1403 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, int tests)
1404 {
1405 // initialize Random number generator
1406 time_t t;
1407 srand((unsigned) time(&t));
1408
1409 if (trgkey != NULL) {
1410 known_target_key = bytes_to_num(trgkey, 6);
1411 } else {
1412 known_target_key = -1;
1413 }
1414
1415 init_partial_statelists();
1416 init_BitFlip_statelist();
1417 write_stats = false;
1418
1419 if (tests) {
1420 // set the correct locale for the stats printing
1421 setlocale(LC_ALL, "");
1422 write_stats = true;
1423 if ((fstats = fopen("hardnested_stats.txt","a")) == NULL) {
1424 PrintAndLog("Could not create/open file hardnested_stats.txt");
1425 return 3;
1426 }
1427 for (uint32_t i = 0; i < tests; i++) {
1428 init_nonce_memory();
1429 simulate_acquire_nonces();
1430 Tests();
1431 printf("Sum(a0) = %d\n", first_byte_Sum);
1432 fprintf(fstats, "%d;", first_byte_Sum);
1433 generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess);
1434 brute_force();
1435 free_nonces_memory();
1436 free_statelist_cache();
1437 free_candidates_memory(candidates);
1438 candidates = NULL;
1439 }
1440 fclose(fstats);
1441 } else {
1442 init_nonce_memory();
1443 if (nonce_file_read) { // use pre-acquired data from file nonces.bin
1444 if (read_nonce_file() != 0) {
1445 return 3;
1446 }
1447 Check_for_FilterFlipProperties();
1448 num_good_first_bytes = MIN(estimate_second_byte_sum(), GOOD_BYTES_REQUIRED);
1449 } else { // acquire nonces.
1450 uint16_t is_OK = acquire_nonces(blockNo, keyType, key, trgBlockNo, trgKeyType, nonce_file_write, slow);
1451 if (is_OK != 0) {
1452 return is_OK;
1453 }
1454 }
1455
1456 Tests();
1457
1458 PrintAndLog("");
1459 PrintAndLog("Sum(a0) = %d", first_byte_Sum);
1460 // PrintAndLog("Best 10 first bytes: %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x",
1461 // best_first_bytes[0],
1462 // best_first_bytes[1],
1463 // best_first_bytes[2],
1464 // best_first_bytes[3],
1465 // best_first_bytes[4],
1466 // best_first_bytes[5],
1467 // best_first_bytes[6],
1468 // best_first_bytes[7],
1469 // best_first_bytes[8],
1470 // best_first_bytes[9] );
1471 PrintAndLog("Number of first bytes with confidence > %2.1f%%: %d", CONFIDENCE_THRESHOLD*100.0, num_good_first_bytes);
1472
1473 clock_t time1 = clock();
1474 generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess);
1475 time1 = clock() - time1;
1476 if ( time1 > 0 )
1477 PrintAndLog("Time for generating key candidates list: %1.0f seconds", ((float)time1)/CLOCKS_PER_SEC);
1478
1479 brute_force();
1480 free_nonces_memory();
1481 free_statelist_cache();
1482 free_candidates_memory(candidates);
1483 candidates = NULL;
1484 }
1485 return 0;
1486 }
1487
1488
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