]>
Commit | Line | Data |
---|---|---|
8ce3e4b4 | 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 <math.h> | |
22 | #include "proxmark3.h" | |
23 | #include "cmdmain.h" | |
24 | #include "ui.h" | |
25 | #include "util.h" | |
26 | #include "nonce2key/crapto1.h" | |
27 | ||
28 | // uint32_t test_state_odd = 0; | |
29 | // uint32_t test_state_even = 0; | |
30 | ||
31 | #define CONFIDENCE_THRESHOLD 0.99 // Collect nonces until we are certain enough that the following brute force is successfull | |
32 | #define GOOD_BYTES_REQUIRED 25 | |
33 | ||
34 | ||
35 | static const float p_K[257] = { // the probability that a random nonce has a Sum Property == K | |
36 | 0.0290, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
37 | 0.0000, 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 | 0.0083, 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 | 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
43 | 0.0006, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
44 | 0.0339, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
45 | 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
46 | 0.0048, 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 | 0.0934, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
49 | 0.0119, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
50 | 0.0489, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
51 | 0.0602, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
52 | 0.4180, 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 | 0.0489, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
55 | 0.0119, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
56 | 0.0934, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
57 | 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
58 | 0.0048, 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 | 0.0339, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
61 | 0.0006, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, | |
62 | 0.0000, 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 | 0.0083, 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 | 0.0000, 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 | 0.0290 }; | |
69 | ||
70 | ||
71 | typedef struct noncelistentry { | |
72 | uint32_t nonce_enc; | |
73 | uint8_t par_enc; | |
74 | void *next; | |
75 | } noncelistentry_t; | |
76 | ||
77 | typedef struct noncelist { | |
78 | uint16_t num; | |
79 | uint16_t Sum; | |
80 | uint16_t Sum8_guess; | |
81 | uint8_t BitFlip[2]; | |
82 | float Sum8_prob; | |
83 | bool updated; | |
84 | noncelistentry_t *first; | |
85 | } noncelist_t; | |
86 | ||
87 | ||
88 | static uint32_t cuid; | |
89 | static noncelist_t nonces[256]; | |
90 | static uint16_t first_byte_Sum = 0; | |
91 | static uint16_t first_byte_num = 0; | |
92 | static uint16_t num_good_first_bytes = 0; | |
93 | ||
94 | #define MAX_BEST_BYTES 40 | |
95 | static uint8_t best_first_bytes[MAX_BEST_BYTES]; | |
96 | ||
97 | ||
98 | typedef enum { | |
99 | EVEN_STATE = 0, | |
100 | ODD_STATE = 1 | |
101 | } odd_even_t; | |
102 | ||
103 | #define STATELIST_INDEX_WIDTH 16 | |
104 | #define STATELIST_INDEX_SIZE (1<<STATELIST_INDEX_WIDTH) | |
105 | ||
106 | typedef struct { | |
107 | uint32_t *states[2]; | |
108 | uint32_t len[2]; | |
109 | uint32_t *index[2][STATELIST_INDEX_SIZE]; | |
110 | } partial_indexed_statelist_t; | |
111 | ||
112 | typedef struct { | |
113 | uint32_t *states[2]; | |
114 | uint32_t len[2]; | |
115 | void* next; | |
116 | } statelist_t; | |
117 | ||
118 | ||
119 | partial_indexed_statelist_t partial_statelist[17]; | |
120 | partial_indexed_statelist_t statelist_bitflip; | |
121 | ||
122 | statelist_t *candidates = NULL; | |
123 | ||
124 | ||
125 | static int add_nonce(uint32_t nonce_enc, uint8_t par_enc) | |
126 | { | |
127 | uint8_t first_byte = nonce_enc >> 24; | |
128 | noncelistentry_t *p1 = nonces[first_byte].first; | |
129 | noncelistentry_t *p2 = NULL; | |
130 | ||
131 | if (p1 == NULL) { // first nonce with this 1st byte | |
132 | first_byte_num++; | |
133 | first_byte_Sum += parity((nonce_enc & 0xff000000) | (par_enc & 0x08) | 0x01); // 1st byte sum property. Note: added XOR 1 | |
134 | // printf("Adding nonce 0x%08x, par_enc 0x%02x, parity(0x%08x) = %d\n", | |
135 | // nonce_enc, | |
136 | // par_enc, | |
137 | // (nonce_enc & 0xff000000) | (par_enc & 0x08) |0x01, | |
138 | // parity((nonce_enc & 0xff000000) | (par_enc & 0x08) | 0x01)); | |
139 | } | |
140 | ||
141 | while (p1 != NULL && (p1->nonce_enc & 0x00ff0000) < (nonce_enc & 0x00ff0000)) { | |
142 | p2 = p1; | |
143 | p1 = p1->next; | |
144 | } | |
145 | ||
146 | if (p1 == NULL) { // need to add at the end of the list | |
147 | if (p2 == NULL) { // list is empty yet. Add first entry. | |
148 | p2 = nonces[first_byte].first = malloc(sizeof(noncelistentry_t)); | |
149 | } else { // add new entry at end of existing list. | |
150 | p2 = p2->next = malloc(sizeof(noncelistentry_t)); | |
151 | } | |
152 | } else if ((p1->nonce_enc & 0x00ff0000) != (nonce_enc & 0x00ff0000)) { // found distinct 2nd byte. Need to insert. | |
153 | if (p2 == NULL) { // need to insert at start of list | |
154 | p2 = nonces[first_byte].first = malloc(sizeof(noncelistentry_t)); | |
155 | } else { | |
156 | p2 = p2->next = malloc(sizeof(noncelistentry_t)); | |
157 | } | |
158 | } else { // we have seen this 2nd byte before. Nothing to add or insert. | |
159 | return (0); | |
160 | } | |
161 | ||
162 | // add or insert new data | |
163 | p2->next = p1; | |
164 | p2->nonce_enc = nonce_enc; | |
165 | p2->par_enc = par_enc; | |
166 | ||
167 | nonces[first_byte].num++; | |
168 | nonces[first_byte].Sum += parity((nonce_enc & 0x00ff0000) | (par_enc & 0x04) | 0x01); // 2nd byte sum property. Note: added XOR 1 | |
169 | nonces[first_byte].updated = true; // indicates that we need to recalculate the Sum(a8) probability for this first byte | |
170 | ||
171 | return (1); // new nonce added | |
172 | } | |
173 | ||
174 | ||
175 | static uint16_t PartialSumProperty(uint32_t state, odd_even_t odd_even) | |
176 | { | |
177 | uint16_t sum = 0; | |
178 | for (uint16_t j = 0; j < 16; j++) { | |
179 | uint32_t st = state; | |
180 | uint16_t part_sum = 0; | |
181 | if (odd_even == ODD_STATE) { | |
182 | for (uint16_t i = 0; i < 5; i++) { | |
183 | part_sum ^= filter(st); | |
184 | st = (st << 1) | ((j >> (3-i)) & 0x01) ; | |
185 | } | |
186 | } else { | |
187 | for (uint16_t i = 0; i < 4; i++) { | |
188 | st = (st << 1) | ((j >> (3-i)) & 0x01) ; | |
189 | part_sum ^= filter(st); | |
190 | } | |
191 | } | |
192 | sum += part_sum; | |
193 | } | |
194 | return sum; | |
195 | } | |
196 | ||
197 | ||
198 | static uint16_t SumProperty(struct Crypto1State *s) | |
199 | { | |
200 | uint16_t sum_odd = PartialSumProperty(s->odd, ODD_STATE); | |
201 | uint16_t sum_even = PartialSumProperty(s->even, EVEN_STATE); | |
202 | return (sum_odd*(16-sum_even) + (16-sum_odd)*sum_even); | |
203 | } | |
204 | ||
205 | ||
206 | static double p_hypergeometric(uint16_t N, uint16_t K, uint16_t n, uint16_t k) | |
207 | { | |
208 | // for efficient computation we are using the recursive definition | |
209 | // (K-k+1) * (n-k+1) | |
210 | // P(X=k) = P(X=k-1) * -------------------- | |
211 | // k * (N-K-n+k) | |
212 | // and | |
213 | // (N-K)*(N-K-1)*...*(N-K-n+1) | |
214 | // P(X=0) = ----------------------------- | |
215 | // N*(N-1)*...*(N-n+1) | |
216 | ||
217 | if (n-k > N-K || k > K) return 0.0; // avoids log(x<=0) in calculation below | |
218 | if (k == 0) { | |
219 | // use logarithms to avoid overflow with huge factorials (double type can only hold 170!) | |
220 | double log_result = 0.0; | |
221 | for (int16_t i = N-K; i >= N-K-n+1; i--) { | |
222 | log_result += log(i); | |
223 | } | |
224 | for (int16_t i = N; i >= N-n+1; i--) { | |
225 | log_result -= log(i); | |
226 | } | |
227 | return exp(log_result); | |
228 | } else { | |
229 | if (n-k == N-K) { // special case. The published recursion below would fail with a divide by zero exception | |
230 | double log_result = 0.0; | |
231 | for (int16_t i = k+1; i <= n; i++) { | |
232 | log_result += log(i); | |
233 | } | |
234 | for (int16_t i = K+1; i <= N; i++) { | |
235 | log_result -= log(i); | |
236 | } | |
237 | return exp(log_result); | |
238 | } else { // recursion | |
239 | return (p_hypergeometric(N, K, n, k-1) * (K-k+1) * (n-k+1) / (k * (N-K-n+k))); | |
240 | } | |
241 | } | |
242 | } | |
243 | ||
244 | ||
245 | static float sum_probability(uint16_t K, uint16_t n, uint16_t k) | |
246 | { | |
247 | const uint16_t N = 256; | |
248 | ||
249 | ||
250 | ||
251 | if (k > K || p_K[K] == 0.0) return 0.0; | |
252 | ||
253 | double p_T_is_k_when_S_is_K = p_hypergeometric(N, K, n, k); | |
254 | double p_S_is_K = p_K[K]; | |
255 | double p_T_is_k = 0; | |
256 | for (uint16_t i = 0; i <= 256; i++) { | |
257 | if (p_K[i] != 0.0) { | |
258 | p_T_is_k += p_K[i] * p_hypergeometric(N, i, n, k); | |
259 | } | |
260 | } | |
261 | return(p_T_is_k_when_S_is_K * p_S_is_K / p_T_is_k); | |
262 | } | |
263 | ||
264 | ||
265 | static void Tests() | |
266 | { | |
267 | printf("Tests: Partial Statelist sizes\n"); | |
268 | for (uint16_t i = 0; i <= 16; i+=2) { | |
269 | printf("Partial State List Odd [%2d] has %8d entries\n", i, partial_statelist[i].len[ODD_STATE]); | |
270 | } | |
271 | for (uint16_t i = 0; i <= 16; i+=2) { | |
272 | printf("Partial State List Even [%2d] has %8d entries\n", i, partial_statelist[i].len[EVEN_STATE]); | |
273 | } | |
274 | ||
275 | // #define NUM_STATISTICS 100000 | |
276 | // uint64_t statistics[257]; | |
277 | // uint32_t statistics_odd[17]; | |
278 | // uint32_t statistics_even[17]; | |
279 | // struct Crypto1State cs; | |
280 | // time_t time1 = clock(); | |
281 | ||
282 | // for (uint16_t i = 0; i < 257; i++) { | |
283 | // statistics[i] = 0; | |
284 | // } | |
285 | // for (uint16_t i = 0; i < 17; i++) { | |
286 | // statistics_odd[i] = 0; | |
287 | // statistics_even[i] = 0; | |
288 | // } | |
289 | ||
290 | // for (uint64_t i = 0; i < NUM_STATISTICS; i++) { | |
291 | // cs.odd = (rand() & 0xfff) << 12 | (rand() & 0xfff); | |
292 | // cs.even = (rand() & 0xfff) << 12 | (rand() & 0xfff); | |
293 | // uint16_t sum_property = SumProperty(&cs); | |
294 | // statistics[sum_property] += 1; | |
295 | // sum_property = PartialSumProperty(cs.even, EVEN_STATE); | |
296 | // statistics_even[sum_property]++; | |
297 | // sum_property = PartialSumProperty(cs.odd, ODD_STATE); | |
298 | // statistics_odd[sum_property]++; | |
299 | // if (i%(NUM_STATISTICS/100) == 0) printf("."); | |
300 | // } | |
301 | ||
302 | // 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); | |
303 | // for (uint16_t i = 0; i < 257; i++) { | |
304 | // if (statistics[i] != 0) { | |
305 | // printf("probability[%3d] = %0.5f\n", i, (float)statistics[i]/NUM_STATISTICS); | |
306 | // } | |
307 | // } | |
308 | // for (uint16_t i = 0; i <= 16; i++) { | |
309 | // if (statistics_odd[i] != 0) { | |
310 | // printf("probability odd [%2d] = %0.5f\n", i, (float)statistics_odd[i]/NUM_STATISTICS); | |
311 | // } | |
312 | // } | |
313 | // for (uint16_t i = 0; i <= 16; i++) { | |
314 | // if (statistics_odd[i] != 0) { | |
315 | // printf("probability even [%2d] = %0.5f\n", i, (float)statistics_even[i]/NUM_STATISTICS); | |
316 | // } | |
317 | // } | |
318 | ||
319 | // printf("Tests: Sum Probabilities based on Partial Sums\n"); | |
320 | // for (uint16_t i = 0; i < 257; i++) { | |
321 | // statistics[i] = 0; | |
322 | // } | |
323 | // uint64_t num_states = 0; | |
324 | // for (uint16_t oddsum = 0; oddsum <= 16; oddsum += 2) { | |
325 | // for (uint16_t evensum = 0; evensum <= 16; evensum += 2) { | |
326 | // uint16_t sum = oddsum*(16-evensum) + (16-oddsum)*evensum; | |
327 | // statistics[sum] += (uint64_t)partial_statelist[oddsum].len[ODD_STATE] * partial_statelist[evensum].len[EVEN_STATE] * (1<<8); | |
328 | // num_states += (uint64_t)partial_statelist[oddsum].len[ODD_STATE] * partial_statelist[evensum].len[EVEN_STATE] * (1<<8); | |
329 | // } | |
330 | // } | |
331 | // printf("num_states = %lld, expected %lld\n", num_states, (1LL<<48)); | |
332 | // for (uint16_t i = 0; i < 257; i++) { | |
333 | // if (statistics[i] != 0) { | |
334 | // printf("probability[%3d] = %0.5f\n", i, (float)statistics[i]/num_states); | |
335 | // } | |
336 | // } | |
337 | ||
338 | // printf("\nTests: Hypergeometric Probability for selected parameters\n"); | |
339 | // printf("p_hypergeometric(256, 206, 255, 206) = %0.8f\n", p_hypergeometric(256, 206, 255, 206)); | |
340 | // printf("p_hypergeometric(256, 206, 255, 205) = %0.8f\n", p_hypergeometric(256, 206, 255, 205)); | |
341 | // printf("p_hypergeometric(256, 156, 1, 1) = %0.8f\n", p_hypergeometric(256, 156, 1, 1)); | |
342 | // printf("p_hypergeometric(256, 156, 1, 0) = %0.8f\n", p_hypergeometric(256, 156, 1, 0)); | |
343 | // printf("p_hypergeometric(256, 1, 1, 1) = %0.8f\n", p_hypergeometric(256, 1, 1, 1)); | |
344 | // printf("p_hypergeometric(256, 1, 1, 0) = %0.8f\n", p_hypergeometric(256, 1, 1, 0)); | |
345 | ||
346 | struct Crypto1State *pcs; | |
347 | pcs = crypto1_create(0xffffffffffff); | |
348 | printf("\nTests: for key = 0xffffffffffff:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n", | |
349 | SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff); | |
350 | crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true); | |
351 | printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n", | |
352 | best_first_bytes[0], | |
353 | SumProperty(pcs), | |
354 | pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff); | |
355 | //test_state_odd = pcs->odd & 0x00ffffff; | |
356 | //test_state_even = pcs->even & 0x00ffffff; | |
357 | crypto1_destroy(pcs); | |
358 | pcs = crypto1_create(0xa0a1a2a3a4a5); | |
359 | printf("Tests: for key = 0xa0a1a2a3a4a5:\nSum(a0) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n", | |
360 | SumProperty(pcs), pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff); | |
361 | crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true); | |
362 | printf("After adding best first byte 0x%02x:\nSum(a8) = %d\nodd_state = 0x%06x\neven_state = 0x%06x\n", | |
363 | best_first_bytes[0], | |
364 | SumProperty(pcs), | |
365 | pcs->odd & 0x00ffffff, pcs->even & 0x00ffffff); | |
366 | // test_state_odd = pcs->odd & 0x00ffffff; | |
367 | // test_state_even = pcs->even & 0x00ffffff; | |
368 | crypto1_destroy(pcs); | |
369 | ||
370 | ||
371 | 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)); | |
372 | ||
373 | printf("\nTests: Actual BitFlipProperties odd/even:\n"); | |
374 | for (uint16_t i = 0; i < 256; i++) { | |
375 | printf("[%3d]:%c%c ", i, nonces[i].BitFlip[ODD_STATE]?'o':' ', nonces[i].BitFlip[EVEN_STATE]?'e':' '); | |
376 | if (i % 8 == 7) { | |
377 | printf("\n"); | |
378 | } | |
379 | } | |
380 | ||
381 | printf("\nTests: Best %d first bytes:\n", MAX_BEST_BYTES); | |
382 | for (uint16_t i = 0; i < MAX_BEST_BYTES; i++) { | |
383 | uint8_t best_byte = best_first_bytes[i]; | |
384 | uint16_t best_num = nonces[best_byte].num; | |
385 | uint16_t best_sum = nonces[best_byte].Sum; | |
386 | uint16_t best_sum8 = nonces[best_byte].Sum8_guess; | |
387 | float confidence = nonces[best_byte].Sum8_prob; | |
388 | printf("Byte: %02x, n = %2d, k = %2d, Sum(a8): %3d, Confidence: %2.1f%%\n", best_byte, best_num, best_sum, best_sum8, confidence*100); | |
389 | } | |
390 | } | |
391 | ||
392 | ||
393 | static void sort_best_first_bytes(void) | |
394 | { | |
395 | // find the best choice for the very first byte (b) | |
396 | float min_p_K = 1.0; | |
397 | float max_prob_min_p_K = 0.0; | |
398 | uint8_t best_byte = 0; | |
399 | for (uint16_t i = 0; i < 256; i++ ) { | |
400 | float prob1 = nonces[i].Sum8_prob; | |
401 | uint16_t sum8 = nonces[i].Sum8_guess; | |
402 | if (p_K[sum8] <= min_p_K && prob1 > CONFIDENCE_THRESHOLD) { | |
403 | if (p_K[sum8] < min_p_K) { | |
404 | min_p_K = p_K[sum8]; | |
405 | best_byte = i; | |
406 | max_prob_min_p_K = prob1; | |
407 | } else if (prob1 > max_prob_min_p_K) { | |
408 | max_prob_min_p_K = prob1; | |
409 | best_byte = i; | |
410 | } | |
411 | } | |
412 | } | |
413 | best_first_bytes[0] = best_byte; | |
414 | // printf("Best Byte = 0x%02x, Sum8=%d, prob=%1.3f\n", best_byte, nonces[best_byte].Sum8_guess, nonces[best_byte].Sum8_prob); | |
415 | ||
416 | // sort the most probable guesses as following bytes (b') | |
417 | for (uint16_t i = 0; i < 256; i++ ) { | |
418 | if (i == best_first_bytes[0]) { | |
419 | continue; | |
420 | } | |
421 | uint16_t j = 1; | |
422 | float prob1 = nonces[i].Sum8_prob; | |
423 | float prob2 = nonces[best_first_bytes[1]].Sum8_prob; | |
424 | while (prob1 < prob2 && j < MAX_BEST_BYTES-1) { | |
425 | prob2 = nonces[best_first_bytes[++j]].Sum8_prob; | |
426 | } | |
427 | if (prob1 >= prob2) { | |
428 | for (uint16_t k = MAX_BEST_BYTES-1; k > j; k--) { | |
429 | best_first_bytes[k] = best_first_bytes[k-1]; | |
430 | } | |
431 | best_first_bytes[j] = i; | |
432 | } | |
433 | } | |
434 | } | |
435 | ||
436 | ||
437 | static uint16_t estimate_second_byte_sum(void) | |
438 | { | |
439 | for (uint16_t i = 0; i < MAX_BEST_BYTES; i++) { | |
440 | best_first_bytes[i] = 0; | |
441 | } | |
442 | ||
443 | for (uint16_t first_byte = 0; first_byte < 256; first_byte++) { | |
444 | float Sum8_prob = 0.0; | |
445 | uint16_t Sum8 = 0; | |
446 | if (nonces[first_byte].updated) { | |
447 | for (uint16_t sum = 0; sum <= 256; sum++) { | |
448 | float prob = sum_probability(sum, nonces[first_byte].num, nonces[first_byte].Sum); | |
449 | if (prob > Sum8_prob) { | |
450 | Sum8_prob = prob; | |
451 | Sum8 = sum; | |
452 | } | |
453 | } | |
454 | nonces[first_byte].Sum8_guess = Sum8; | |
455 | nonces[first_byte].Sum8_prob = Sum8_prob; | |
456 | nonces[first_byte].updated = false; | |
457 | } | |
458 | } | |
459 | ||
460 | sort_best_first_bytes(); | |
461 | ||
462 | uint16_t num_good_nonces = 0; | |
463 | for (uint16_t i = 0; i < MAX_BEST_BYTES; i++) { | |
464 | if (nonces[best_first_bytes[i]].Sum8_prob > CONFIDENCE_THRESHOLD) { | |
465 | ++num_good_nonces; | |
466 | } | |
467 | } | |
468 | ||
469 | return num_good_nonces; | |
470 | } | |
471 | ||
472 | ||
473 | static int read_nonce_file(void) | |
474 | { | |
475 | FILE *fnonces = NULL; | |
476 | uint8_t trgBlockNo; | |
477 | uint8_t trgKeyType; | |
478 | uint8_t read_buf[9]; | |
479 | uint32_t nt_enc1, nt_enc2; | |
480 | uint8_t par_enc; | |
481 | int total_num_nonces = 0; | |
482 | ||
483 | if ((fnonces = fopen("nonces.bin","rb")) == NULL) { | |
484 | PrintAndLog("Could not open file nonces.bin"); | |
485 | return 1; | |
486 | } | |
487 | ||
488 | PrintAndLog("Reading nonces from file nonces.bin..."); | |
489 | if (fread(read_buf, 1, 6, fnonces) == 0) { | |
490 | PrintAndLog("File reading error."); | |
491 | fclose(fnonces); | |
492 | return 1; | |
493 | } | |
494 | cuid = bytes_to_num(read_buf, 4); | |
495 | trgBlockNo = bytes_to_num(read_buf+4, 1); | |
496 | trgKeyType = bytes_to_num(read_buf+5, 1); | |
497 | ||
498 | while (fread(read_buf, 1, 9, fnonces) == 9) { | |
499 | nt_enc1 = bytes_to_num(read_buf, 4); | |
500 | nt_enc2 = bytes_to_num(read_buf+4, 4); | |
501 | par_enc = bytes_to_num(read_buf+8, 1); | |
502 | //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4); | |
503 | //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f); | |
504 | add_nonce(nt_enc1, par_enc >> 4); | |
505 | add_nonce(nt_enc2, par_enc & 0x0f); | |
506 | total_num_nonces += 2; | |
507 | } | |
508 | fclose(fnonces); | |
509 | PrintAndLog("Read %d nonces from file. cuid=%08x, Block=%d, Keytype=%c", total_num_nonces, cuid, trgBlockNo, trgKeyType==0?'A':'B'); | |
510 | ||
511 | return 0; | |
512 | } | |
513 | ||
514 | ||
515 | int static acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, bool nonce_file_write, bool slow) | |
516 | { | |
517 | clock_t time1 = clock(); | |
518 | bool initialize = true; | |
519 | bool field_off = false; | |
520 | bool finished = false; | |
521 | uint32_t flags = 0; | |
522 | uint8_t write_buf[9]; | |
523 | uint32_t total_num_nonces = 0; | |
524 | uint32_t next_fivehundred = 500; | |
525 | uint32_t total_added_nonces = 0; | |
526 | FILE *fnonces = NULL; | |
527 | UsbCommand resp; | |
528 | ||
529 | printf("Acquiring nonces...\n"); | |
530 | ||
531 | clearCommandBuffer(); | |
532 | ||
533 | do { | |
534 | flags = 0; | |
535 | flags |= initialize ? 0x0001 : 0; | |
536 | flags |= slow ? 0x0002 : 0; | |
537 | flags |= field_off ? 0x0004 : 0; | |
538 | UsbCommand c = {CMD_MIFARE_ACQUIRE_ENCRYPTED_NONCES, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, flags}}; | |
539 | memcpy(c.d.asBytes, key, 6); | |
540 | ||
541 | SendCommand(&c); | |
542 | ||
543 | if (field_off) finished = true; | |
544 | ||
545 | if (initialize) { | |
546 | if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) return 1; | |
547 | if (resp.arg[0]) return resp.arg[0]; // error during nested_hard | |
548 | ||
549 | cuid = resp.arg[1]; | |
550 | // PrintAndLog("Acquiring nonces for CUID 0x%08x", cuid); | |
551 | if (nonce_file_write && fnonces == NULL) { | |
552 | if ((fnonces = fopen("nonces.bin","wb")) == NULL) { | |
553 | PrintAndLog("Could not create file nonces.bin"); | |
554 | return 3; | |
555 | } | |
556 | PrintAndLog("Writing acquired nonces to binary file nonces.bin"); | |
557 | num_to_bytes(cuid, 4, write_buf); | |
558 | fwrite(write_buf, 1, 4, fnonces); | |
559 | fwrite(&trgBlockNo, 1, 1, fnonces); | |
560 | fwrite(&trgKeyType, 1, 1, fnonces); | |
561 | } | |
562 | } | |
563 | ||
564 | if (!initialize) { | |
565 | uint32_t nt_enc1, nt_enc2; | |
566 | uint8_t par_enc; | |
567 | uint16_t num_acquired_nonces = resp.arg[2]; | |
568 | uint8_t *bufp = resp.d.asBytes; | |
569 | for (uint16_t i = 0; i < num_acquired_nonces; i+=2) { | |
570 | nt_enc1 = bytes_to_num(bufp, 4); | |
571 | nt_enc2 = bytes_to_num(bufp+4, 4); | |
572 | par_enc = bytes_to_num(bufp+8, 1); | |
573 | ||
574 | //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4); | |
575 | total_added_nonces += add_nonce(nt_enc1, par_enc >> 4); | |
576 | //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f); | |
577 | total_added_nonces += add_nonce(nt_enc2, par_enc & 0x0f); | |
578 | ||
579 | ||
580 | if (nonce_file_write) { | |
581 | fwrite(bufp, 1, 9, fnonces); | |
582 | } | |
583 | ||
584 | bufp += 9; | |
585 | } | |
586 | ||
587 | total_num_nonces += num_acquired_nonces; | |
588 | } | |
589 | ||
590 | if (first_byte_num == 256 ) { | |
591 | // printf("first_byte_num = %d, first_byte_Sum = %d\n", first_byte_num, first_byte_Sum); | |
592 | num_good_first_bytes = estimate_second_byte_sum(); | |
593 | if (total_num_nonces > next_fivehundred) { | |
594 | next_fivehundred = (total_num_nonces/500+1) * 500; | |
595 | 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", | |
596 | total_num_nonces, | |
597 | total_added_nonces, | |
598 | CONFIDENCE_THRESHOLD * 100.0, | |
599 | num_good_first_bytes); | |
600 | } | |
601 | if (num_good_first_bytes >= GOOD_BYTES_REQUIRED) { | |
602 | field_off = true; // switch off field with next SendCommand and then finish | |
603 | } | |
604 | } | |
605 | ||
606 | if (!initialize) { | |
607 | if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) return 1; | |
608 | if (resp.arg[0]) return resp.arg[0]; // error during nested_hard | |
609 | } | |
610 | ||
611 | initialize = false; | |
612 | ||
613 | } while (!finished); | |
614 | ||
615 | ||
616 | if (nonce_file_write) { | |
617 | fclose(fnonces); | |
618 | } | |
619 | ||
620 | PrintAndLog("Acquired a total of %d nonces in %1.1f seconds (%d nonces/minute)", | |
621 | total_num_nonces, | |
622 | ((float)clock()-time1)/CLOCKS_PER_SEC, | |
623 | total_num_nonces*60*CLOCKS_PER_SEC/(clock()-time1)); | |
624 | ||
625 | return 0; | |
626 | } | |
627 | ||
628 | ||
629 | static int init_partial_statelists(void) | |
630 | { | |
631 | const uint32_t sizes_odd[17] = { 125601, 0, 17607, 0, 73421, 0, 182033, 0, 248801, 0, 181737, 0, 74241, 0, 18387, 0, 126757 }; | |
632 | const uint32_t sizes_even[17] = { 125723, 0, 17867, 0, 74305, 0, 178707, 0, 248801, 0, 185063, 0, 73356, 0, 18127, 0, 126634 }; | |
633 | ||
634 | printf("Allocating memory for partial statelists...\n"); | |
635 | for (odd_even_t odd_even = EVEN_STATE; odd_even <= ODD_STATE; odd_even++) { | |
636 | for (uint16_t i = 0; i <= 16; i+=2) { | |
637 | partial_statelist[i].len[odd_even] = 0; | |
638 | uint32_t num_of_states = odd_even == ODD_STATE ? sizes_odd[i] : sizes_even[i]; | |
639 | partial_statelist[i].states[odd_even] = malloc(sizeof(uint32_t) * num_of_states); | |
640 | if (partial_statelist[i].states[odd_even] == NULL) { | |
641 | PrintAndLog("Cannot allocate enough memory. Aborting"); | |
642 | return 4; | |
643 | } | |
644 | for (uint32_t j = 0; j < STATELIST_INDEX_SIZE; j++) { | |
645 | partial_statelist[i].index[odd_even][j] = NULL; | |
646 | } | |
647 | } | |
648 | } | |
649 | ||
650 | printf("Generating partial statelists...\n"); | |
651 | for (odd_even_t odd_even = EVEN_STATE; odd_even <= ODD_STATE; odd_even++) { | |
652 | uint32_t index = -1; | |
653 | uint32_t num_of_states = 1<<20; | |
654 | for (uint32_t state = 0; state < num_of_states; state++) { | |
655 | uint16_t sum_property = PartialSumProperty(state, odd_even); | |
656 | uint32_t *p = partial_statelist[sum_property].states[odd_even]; | |
657 | p += partial_statelist[sum_property].len[odd_even]; | |
658 | *p = state; | |
659 | partial_statelist[sum_property].len[odd_even]++; | |
660 | uint32_t index_mask = (STATELIST_INDEX_SIZE-1) << (20-STATELIST_INDEX_WIDTH); | |
661 | if ((state & index_mask) != index) { | |
662 | index = state & index_mask; | |
663 | } | |
664 | if (partial_statelist[sum_property].index[odd_even][index >> (20-STATELIST_INDEX_WIDTH)] == NULL) { | |
665 | partial_statelist[sum_property].index[odd_even][index >> (20-STATELIST_INDEX_WIDTH)] = p; | |
666 | } | |
667 | } | |
668 | // add End Of List markers | |
669 | for (uint16_t i = 0; i <= 16; i += 2) { | |
670 | uint32_t *p = partial_statelist[i].states[odd_even]; | |
671 | p += partial_statelist[i].len[odd_even]; | |
672 | *p = 0xffffffff; | |
673 | } | |
674 | } | |
675 | ||
676 | return 0; | |
677 | } | |
678 | ||
679 | ||
680 | static void init_BitFlip_statelist(void) | |
681 | { | |
682 | printf("Generating bitflip statelist...\n"); | |
683 | uint32_t *p = statelist_bitflip.states[0] = malloc(sizeof(uint32_t) * 1<<20); | |
684 | uint32_t index = -1; | |
685 | uint32_t index_mask = (STATELIST_INDEX_SIZE-1) << (20-STATELIST_INDEX_WIDTH); | |
686 | for (uint32_t state = 0; state < (1 << 20); state++) { | |
687 | if (filter(state) != filter(state^1)) { | |
688 | if ((state & index_mask) != index) { | |
689 | index = state & index_mask; | |
690 | } | |
691 | if (statelist_bitflip.index[0][index >> (20-STATELIST_INDEX_WIDTH)] == NULL) { | |
692 | statelist_bitflip.index[0][index >> (20-STATELIST_INDEX_WIDTH)] = p; | |
693 | } | |
694 | *p++ = state; | |
695 | } | |
696 | } | |
697 | // set len and add End Of List marker | |
698 | statelist_bitflip.len[0] = p - statelist_bitflip.states[0]; | |
699 | *p = 0xffffffff; | |
700 | statelist_bitflip.states[0] = realloc(statelist_bitflip.states[0], sizeof(uint32_t) * (statelist_bitflip.len[0] + 1)); | |
701 | } | |
702 | ||
703 | ||
704 | static void add_state(statelist_t *sl, uint32_t state, odd_even_t odd_even) | |
705 | { | |
706 | uint32_t *p; | |
707 | ||
708 | p = sl->states[odd_even]; | |
709 | p += sl->len[odd_even]; | |
710 | *p = state; | |
711 | sl->len[odd_even]++; | |
712 | } | |
713 | ||
714 | ||
715 | uint32_t *find_first_state(uint32_t state, uint32_t mask, partial_indexed_statelist_t *sl, odd_even_t odd_even) | |
716 | { | |
717 | uint32_t *p = sl->index[odd_even][(state & mask) >> (20-STATELIST_INDEX_WIDTH)]; // first Bits as index | |
718 | ||
719 | if (p == NULL) return NULL; | |
720 | while ((*p & mask) < (state & mask)) p++; | |
721 | if (*p == 0xffffffff) return NULL; // reached end of list, no match | |
722 | if ((*p & mask) == (state & mask)) return p; // found a match. | |
723 | return NULL; // no match | |
724 | } | |
725 | ||
726 | ||
727 | static bool remaining_bits_match(uint8_t num_common_bits, uint8_t byte1, uint8_t byte2, uint32_t state1, uint32_t state2, odd_even_t odd_even) | |
728 | { | |
729 | uint8_t j = num_common_bits; | |
730 | if (odd_even == ODD_STATE) { | |
731 | j |= 0x01; // consider the next odd bit | |
732 | } else { | |
733 | j = (j+1) & 0xfe; // consider the next even bit | |
734 | } | |
735 | ||
736 | while (j <= 7) { | |
737 | if (j != num_common_bits) { // this is not the first differing bit, we need first to check if the invariant still holds | |
738 | uint32_t bit_diff = ((byte1 ^ byte2) << (17-j)) & 0x00010000; // difference of (j-1)th bit -> bit 16 | |
739 | uint32_t filter_diff = filter(state1 >> (4-j/2)) ^ filter(state2 >> (4-j/2)); // difference in filter function -> bit 0 | |
740 | uint32_t mask_y12_y13 = 0x000000c0 >> (j/2); | |
741 | uint32_t state_diff = (state1 ^ state2) & mask_y12_y13; // difference in state bits 12 and 13 -> bits 6/7 ... 4/5 | |
742 | uint32_t all_diff = parity(bit_diff | state_diff | filter_diff); // use parity function to XOR all 4 bits | |
743 | if (all_diff) { // invariant doesn't hold any more. Accept this state. | |
744 | // if ((odd_even == ODD_STATE && state1 == test_state_odd) | |
745 | // || (odd_even == EVEN_STATE && state1 == test_state_even)) { | |
746 | // printf("remaining_bits_match(): %s test state: Invariant doesn't hold. Bytes = %02x, %02x, Common Bits=%d, Testing Bit %d, State1=0x%08x, State2=0x%08x\n", | |
747 | // odd_even==ODD_STATE?"odd":"even", byte1, byte2, num_common_bits, j, state1, state2); | |
748 | // } | |
749 | return true; | |
750 | } | |
751 | } | |
752 | // check for validity of state candidate | |
753 | uint32_t bit_diff = ((byte1 ^ byte2) << (16-j)) & 0x00010000; // difference of jth bit -> bit 16 | |
754 | uint32_t mask_y13_y16 = 0x00000048 >> (j/2); | |
755 | uint32_t state_diff = (state1 ^ state2) & mask_y13_y16; // difference in state bits 13 and 16 -> bits 3/6 ... 0/3 | |
756 | uint32_t all_diff = parity(bit_diff | state_diff); // use parity function to XOR all 3 bits | |
757 | if (all_diff) { // not a valid state | |
758 | // if ((odd_even == ODD_STATE && state1 == test_state_odd) | |
759 | // || (odd_even == EVEN_STATE && state1 == test_state_even)) { | |
760 | // printf("remaining_bits_match(): %s test state: Invalid state. Bytes = %02x, %02x, Common Bits=%d, Testing Bit %d, State1=0x%08x, State2=0x%08x\n", | |
761 | // odd_even==ODD_STATE?"odd":"even", byte1, byte2, num_common_bits, j, state1, state2); | |
762 | // printf(" byte1^byte2: 0x%02x, bit_diff: 0x%08x, state_diff: 0x%08x, all_diff: 0x%08x\n", | |
763 | // byte1^byte2, bit_diff, state_diff, all_diff); | |
764 | // } | |
765 | return false; | |
766 | } | |
767 | // continue checking for the next bit | |
768 | j += 2; | |
769 | } | |
770 | ||
771 | return true; // valid state | |
772 | } | |
773 | ||
774 | ||
775 | static bool all_other_first_bytes_match(uint32_t state, odd_even_t odd_even) | |
776 | { | |
777 | for (uint16_t i = 1; i < num_good_first_bytes; i++) { | |
778 | uint16_t sum_a8 = nonces[best_first_bytes[i]].Sum8_guess; | |
779 | uint8_t j = 0; // number of common bits | |
780 | uint8_t common_bits = best_first_bytes[0] ^ best_first_bytes[i]; | |
781 | uint32_t mask = 0xfffffff0; | |
782 | if (odd_even == ODD_STATE) { | |
783 | while ((common_bits & 0x01) == 0 && j < 8) { | |
784 | j++; | |
785 | common_bits >>= 1; | |
786 | if (j % 2 == 0) { // the odd bits | |
787 | mask >>= 1; | |
788 | } | |
789 | } | |
790 | } else { | |
791 | while ((common_bits & 0x01) == 0 && j < 8) { | |
792 | j++; | |
793 | common_bits >>= 1; | |
794 | if (j % 2 == 1) { // the even bits | |
795 | mask >>= 1; | |
796 | } | |
797 | } | |
798 | } | |
799 | mask &= 0x000fffff; | |
800 | //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); | |
801 | bool found_match = false; | |
802 | for (uint16_t r = 0; r <= 16 && !found_match; r += 2) { | |
803 | for (uint16_t s = 0; s <= 16 && !found_match; s += 2) { | |
804 | if (r*(16-s) + (16-r)*s == sum_a8) { | |
805 | //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); | |
806 | uint16_t part_sum_a8 = (odd_even == ODD_STATE) ? r : s; | |
807 | uint32_t *p = find_first_state(state, mask, &partial_statelist[part_sum_a8], odd_even); | |
808 | if (p != NULL) { | |
809 | while ((state & mask) == (*p & mask) && (*p != 0xffffffff)) { | |
810 | if (remaining_bits_match(j, best_first_bytes[0], best_first_bytes[i], state, (state&0x00fffff0) | *p, odd_even)) { | |
811 | found_match = true; | |
812 | // if ((odd_even == ODD_STATE && state == test_state_odd) | |
813 | // || (odd_even == EVEN_STATE && state == test_state_even)) { | |
814 | // 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", | |
815 | // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8); | |
816 | // } | |
817 | break; | |
818 | } else { | |
819 | // if ((odd_even == ODD_STATE && state == test_state_odd) | |
820 | // || (odd_even == EVEN_STATE && state == test_state_even)) { | |
821 | // 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", | |
822 | // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8); | |
823 | // } | |
824 | } | |
825 | p++; | |
826 | } | |
827 | } else { | |
828 | // if ((odd_even == ODD_STATE && state == test_state_odd) | |
829 | // || (odd_even == EVEN_STATE && state == test_state_even)) { | |
830 | // 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", | |
831 | // odd_even==ODD_STATE?"odd":"even", best_first_bytes[0], best_first_bytes[i], j, mask, part_sum_a8); | |
832 | // } | |
833 | } | |
834 | } | |
835 | } | |
836 | } | |
837 | ||
838 | if (!found_match) { | |
839 | // if ((odd_even == ODD_STATE && state == test_state_odd) | |
840 | // || (odd_even == EVEN_STATE && state == test_state_even)) { | |
841 | // 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); | |
842 | // } | |
843 | return false; | |
844 | } | |
845 | } | |
846 | ||
847 | return true; | |
848 | } | |
849 | ||
850 | ||
851 | static int add_matching_states(statelist_t *candidates, uint16_t part_sum_a0, uint16_t part_sum_a8, odd_even_t odd_even) | |
852 | { | |
853 | uint32_t worstcase_size = 1<<20; | |
854 | ||
855 | candidates->states[odd_even] = (uint32_t *)malloc(sizeof(uint32_t) * worstcase_size); | |
856 | if (candidates->states[odd_even] == NULL) { | |
857 | PrintAndLog("Out of memory error.\n"); | |
858 | return 4; | |
859 | } | |
860 | for (uint32_t *p1 = partial_statelist[part_sum_a0].states[odd_even]; *p1 != 0xffffffff; p1++) { | |
861 | uint32_t search_mask = 0x000ffff0; | |
862 | uint32_t *p2 = find_first_state((*p1 << 4), search_mask, &partial_statelist[part_sum_a8], odd_even); | |
863 | if (p2 != NULL) { | |
864 | while (((*p1 << 4) & search_mask) == (*p2 & search_mask) && *p2 != 0xffffffff) { | |
865 | if (all_other_first_bytes_match((*p1 << 4) | *p2, odd_even)) { | |
866 | add_state(candidates, (*p1 << 4) | *p2, odd_even); | |
867 | } | |
868 | p2++; | |
869 | } | |
870 | } | |
871 | p2 = candidates->states[odd_even]; | |
872 | p2 += candidates->len[odd_even]; | |
873 | *p2 = 0xffffffff; | |
874 | } | |
875 | candidates->states[odd_even] = realloc(candidates->states[odd_even], sizeof(uint32_t) * (candidates->len[odd_even] + 1)); | |
876 | ||
877 | return 0; | |
878 | } | |
879 | ||
880 | ||
881 | static statelist_t *add_more_candidates(statelist_t *current_candidates) | |
882 | { | |
883 | statelist_t *new_candidates = NULL; | |
884 | if (current_candidates == NULL) { | |
885 | if (candidates == NULL) { | |
886 | candidates = (statelist_t *)malloc(sizeof(statelist_t)); | |
887 | } | |
888 | new_candidates = candidates; | |
889 | } else { | |
890 | new_candidates = current_candidates->next = (statelist_t *)malloc(sizeof(statelist_t)); | |
891 | } | |
892 | new_candidates->next = NULL; | |
893 | new_candidates->len[ODD_STATE] = 0; | |
894 | new_candidates->len[EVEN_STATE] = 0; | |
895 | new_candidates->states[ODD_STATE] = NULL; | |
896 | new_candidates->states[EVEN_STATE] = NULL; | |
897 | return new_candidates; | |
898 | } | |
899 | ||
900 | ||
901 | static void TestIfKeyExists(uint64_t key) | |
902 | { | |
903 | struct Crypto1State *pcs; | |
904 | pcs = crypto1_create(key); | |
905 | crypto1_byte(pcs, (cuid >> 24) ^ best_first_bytes[0], true); | |
906 | ||
907 | uint32_t state_odd = pcs->odd & 0x00ffffff; | |
908 | uint32_t state_even = pcs->even & 0x00ffffff; | |
909 | 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); | |
910 | ||
911 | for (statelist_t *p = candidates; p != NULL; p = p->next) { | |
912 | uint32_t *p_odd = p->states[ODD_STATE]; | |
913 | uint32_t *p_even = p->states[EVEN_STATE]; | |
914 | while (*p_odd != 0xffffffff) { | |
915 | if (*p_odd == state_odd) printf("o"); | |
916 | p_odd++; | |
917 | } | |
918 | while (*p_even != 0xffffffff) { | |
919 | if (*p_even == state_even) printf("e"); | |
920 | p_even++; | |
921 | } | |
922 | printf("|"); | |
923 | } | |
924 | printf("\n"); | |
925 | crypto1_destroy(pcs); | |
926 | } | |
927 | ||
928 | ||
929 | static void generate_candidates(uint16_t sum_a0, uint16_t sum_a8) | |
930 | { | |
931 | printf("Generating crypto1 state candidates... \n"); | |
932 | ||
933 | statelist_t *current_candidates = NULL; | |
934 | // estimate maximum candidate states | |
935 | uint64_t maximum_states = 0; | |
936 | for (uint16_t sum_odd = 0; sum_odd <= 16; sum_odd += 2) { | |
937 | for (uint16_t sum_even = 0; sum_even <= 16; sum_even += 2) { | |
938 | if (sum_odd*(16-sum_even) + (16-sum_odd)*sum_even == sum_a0) { | |
939 | maximum_states += (uint64_t)partial_statelist[sum_odd].len[ODD_STATE] * partial_statelist[sum_even].len[EVEN_STATE] * (1<<8); | |
940 | } | |
941 | } | |
942 | } | |
943 | printf("Number of possible keys with Sum(a0) = %d: %lld (2^%1.1f)\n", sum_a0, maximum_states, log(maximum_states)/log(2.0)); | |
944 | ||
945 | for (uint16_t p = 0; p <= 16; p += 2) { | |
946 | for (uint16_t q = 0; q <= 16; q += 2) { | |
947 | if (p*(16-q) + (16-p)*q == sum_a0) { | |
948 | printf("Reducing Partial Statelists (p,q) = (%d,%d) with lengths %d, %d\n", | |
949 | p, q, partial_statelist[p].len[ODD_STATE], partial_statelist[q].len[EVEN_STATE]); | |
950 | for (uint16_t r = 0; r <= 16; r += 2) { | |
951 | for (uint16_t s = 0; s <= 16; s += 2) { | |
952 | if (r*(16-s) + (16-r)*s == sum_a8) { | |
953 | current_candidates = add_more_candidates(current_candidates); | |
954 | add_matching_states(current_candidates, p, r, ODD_STATE); | |
955 | printf("Odd state candidates: %d (2^%0.1f)\n", current_candidates->len[ODD_STATE], log(current_candidates->len[ODD_STATE])/log(2)); | |
956 | add_matching_states(current_candidates, q, s, EVEN_STATE); | |
957 | printf("Even state candidates: %d (2^%0.1f)\n", current_candidates->len[EVEN_STATE], log(current_candidates->len[EVEN_STATE])/log(2)); | |
958 | } | |
959 | } | |
960 | } | |
961 | } | |
962 | } | |
963 | } | |
964 | ||
965 | ||
966 | maximum_states = 0; | |
967 | for (statelist_t *sl = candidates; sl != NULL; sl = sl->next) { | |
968 | maximum_states += (uint64_t)sl->len[ODD_STATE] * sl->len[EVEN_STATE]; | |
969 | } | |
970 | printf("Number of remaining possible keys: %lld (2^%1.1f)\n", maximum_states, log(maximum_states)/log(2.0)); | |
971 | ||
972 | TestIfKeyExists(0xffffffffffff); | |
973 | TestIfKeyExists(0xa0a1a2a3a4a5); | |
974 | ||
975 | } | |
976 | ||
977 | ||
978 | static void Check_for_FilterFlipProperties(void) | |
979 | { | |
980 | printf("Checking for Filter Flip Properties...\n"); | |
981 | ||
982 | for (uint16_t i = 0; i < 256; i++) { | |
983 | nonces[i].BitFlip[ODD_STATE] = false; | |
984 | nonces[i].BitFlip[EVEN_STATE] = false; | |
985 | } | |
986 | ||
987 | for (uint16_t i = 0; i < 256; i++) { | |
988 | uint8_t parity1 = (nonces[i].first->par_enc) >> 3; // parity of first byte | |
989 | uint8_t parity2_odd = (nonces[i^0x80].first->par_enc) >> 3; // XOR 0x80 = last bit flipped | |
990 | uint8_t parity2_even = (nonces[i^0x40].first->par_enc) >> 3; // XOR 0x40 = second last bit flipped | |
991 | ||
992 | if (parity1 == parity2_odd) { // has Bit Flip Property for odd bits | |
993 | nonces[i].BitFlip[ODD_STATE] = true; | |
994 | } else if (parity1 == parity2_even) { // has Bit Flip Property for even bits | |
995 | nonces[i].BitFlip[EVEN_STATE] = true; | |
996 | } | |
997 | } | |
998 | } | |
999 | ||
1000 | ||
1001 | int mfnestedhard(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, bool nonce_file_read, bool nonce_file_write, bool slow) | |
1002 | { | |
1003 | ||
1004 | // initialize the list of nonces | |
1005 | for (uint16_t i = 0; i < 256; i++) { | |
1006 | nonces[i].num = 0; | |
1007 | nonces[i].Sum = 0; | |
1008 | nonces[i].Sum8_guess = 0; | |
1009 | nonces[i].Sum8_prob = 0.0; | |
1010 | nonces[i].updated = true; | |
1011 | nonces[i].first = NULL; | |
1012 | } | |
1013 | first_byte_num = 0; | |
1014 | first_byte_Sum = 0; | |
1015 | num_good_first_bytes = 0; | |
1016 | ||
1017 | init_partial_statelists(); | |
1018 | init_BitFlip_statelist(); | |
1019 | ||
1020 | if (nonce_file_read) { // use pre-acquired data from file nonces.bin | |
1021 | if (read_nonce_file() != 0) { | |
1022 | return 3; | |
1023 | } | |
1024 | num_good_first_bytes = estimate_second_byte_sum(); | |
1025 | } else { // acquire nonces. | |
1026 | uint16_t is_OK = acquire_nonces(blockNo, keyType, key, trgBlockNo, trgKeyType, nonce_file_write, slow); | |
1027 | if (is_OK != 0) { | |
1028 | return is_OK; | |
1029 | } | |
1030 | } | |
1031 | ||
1032 | Check_for_FilterFlipProperties(); | |
1033 | ||
1034 | Tests(); | |
1035 | ||
1036 | PrintAndLog(""); | |
1037 | PrintAndLog("Sum(a0) = %d", first_byte_Sum); | |
1038 | // PrintAndLog("Best 10 first bytes: %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x", | |
1039 | // best_first_bytes[0], | |
1040 | // best_first_bytes[1], | |
1041 | // best_first_bytes[2], | |
1042 | // best_first_bytes[3], | |
1043 | // best_first_bytes[4], | |
1044 | // best_first_bytes[5], | |
1045 | // best_first_bytes[6], | |
1046 | // best_first_bytes[7], | |
1047 | // best_first_bytes[8], | |
1048 | // best_first_bytes[9] ); | |
1049 | PrintAndLog("Number of first bytes with confidence > %2.1f%%: %d", CONFIDENCE_THRESHOLD*100.0, num_good_first_bytes); | |
1050 | ||
1051 | generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess); | |
1052 | ||
1053 | PrintAndLog("Brute force phase not yet implemented"); | |
1054 | ||
1055 | return 0; | |
1056 | } | |
1057 | ||
1058 |