X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/7fd676db11941a7cd20a918e47683d3badf64af1..8e4a0b3585ae9d62acfde915e25dbcd90b56397a:/client/cmdhfmfhard.c?ds=sidebyside diff --git a/client/cmdhfmfhard.c b/client/cmdhfmfhard.c index 4c2e4e1a..39aecb4f 100644 --- a/client/cmdhfmfhard.c +++ b/client/cmdhfmfhard.c @@ -17,8 +17,7 @@ #define CONFIDENCE_THRESHOLD 0.95 // Collect nonces until we are certain enough that the following brute force is successfull #define GOOD_BYTES_REQUIRED 13 // default 28, could be smaller == faster -#define MIN_NONCES_REQUIRED 4000 // 4000-5000 could be good -#define NONCES_TRIGGER 2500 // every 2500 nonces check if we can crack the key +#define NONCES_THRESHOLD 5000 // every N nonces check if we can crack the key #define CRACKING_THRESHOLD 39.00f // as 2^39 #define END_OF_LIST_MARKER 0xFFFFFFFF @@ -114,12 +113,8 @@ static partial_indexed_statelist_t partial_statelist[17]; static partial_indexed_statelist_t statelist_bitflip; static statelist_t *candidates = NULL; -bool thread_check_started = false; -bool thread_check_done = false; bool field_off = false; -pthread_t thread_check; - static bool generate_candidates(uint16_t, uint16_t); static bool brute_force(void); @@ -260,7 +255,7 @@ static double p_hypergeometric(uint16_t N, uint16_t K, uint16_t n, uint16_t k) for (int16_t i = N; i >= N-n+1; i--) { log_result -= log(i); } - return (log_result > 0) ? exp(log_result) : 0.0; + return exp(log_result); } else { if (n-k == N-K) { // special case. The published recursion below would fail with a divide by zero exception double log_result = 0.0; @@ -270,7 +265,7 @@ static double p_hypergeometric(uint16_t N, uint16_t K, uint16_t n, uint16_t k) for (int16_t i = K+1; i <= N; i++) { log_result -= log(i); } - return (log_result > 0) ? exp(log_result) : 0.0; + return exp(log_result); } else { // recursion return (p_hypergeometric(N, K, n, k-1) * (K-k+1) * (n-k+1) / (k * (N-K-n+k))); } @@ -284,9 +279,6 @@ static float sum_probability(uint16_t K, uint16_t n, uint16_t k) if (k > K || p_K[K] == 0.0) return 0.0; double p_T_is_k_when_S_is_K = p_hypergeometric(N, K, n, k); - - if (p_T_is_k_when_S_is_K == 0.0) return 0.0; - double p_S_is_K = p_K[K]; double p_T_is_k = 0; for (uint16_t i = 0; i <= 256; i++) { @@ -564,9 +556,11 @@ static void sort_best_first_bytes(void) } // swap best possible first byte to the pole position + if (best_first_byte != 0) { uint16_t temp = best_first_bytes[0]; best_first_bytes[0] = best_first_bytes[best_first_byte]; best_first_bytes[best_first_byte] = temp; + } } @@ -774,6 +768,7 @@ static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_ flags |= field_off ? 0x0004 : 0; UsbCommand c = {CMD_MIFARE_ACQUIRE_ENCRYPTED_NONCES, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, flags}}; memcpy(c.d.asBytes, key, 6); + clearCommandBuffer(); SendCommand(&c); @@ -838,15 +833,14 @@ static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_ printf("Acquired %5d nonces (%5d / %5d with distinct bytes 0 and 1). Number of bytes with probability for correctly guessed Sum(a8) > %1.1f%%: %d\n", total_num_nonces, total_added_nonces, - (total_added_nonces < MIN_NONCES_REQUIRED) ? MIN_NONCES_REQUIRED : (NONCES_TRIGGER*idx), + NONCES_THRESHOLD * idx, CONFIDENCE_THRESHOLD * 100.0, num_good_first_bytes); } - if (total_added_nonces >= MIN_NONCES_REQUIRED) { + if (total_added_nonces >= (NONCES_THRESHOLD * idx)) + { num_good_first_bytes = estimate_second_byte_sum(); - if (total_added_nonces > (NONCES_TRIGGER * idx)) { - clock_t time1 = clock(); bool cracking = generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess); time1 = clock() - time1; @@ -860,8 +854,6 @@ static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_ } } - } - if (!initialize) { if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) { if (fnonces) fclose(fnonces); @@ -1314,6 +1306,7 @@ static bool generate_candidates(uint16_t sum_a0, uint16_t sum_a8) for (uint16_t s = 0; s <= 16; s += 2) { if (r*(16-s) + (16-r)*s == sum_a8) { current_candidates = add_more_candidates(current_candidates); + if (current_candidates) { // check for the smallest partial statelist. Try this first - it might give 0 candidates // and eliminate the need to calculate the other part if (MIN(partial_statelist[p].len[ODD_STATE], partial_statelist[r].len[ODD_STATE]) @@ -1344,9 +1337,11 @@ static bool generate_candidates(uint16_t sum_a0, uint16_t sum_a8) } } } + } maximum_states = 0; - for (statelist_t *sl = candidates; sl != NULL; sl = sl->next) { + unsigned int n = 0; + for (statelist_t *sl = candidates; sl != NULL && n < 128; sl = sl->next, n++) { maximum_states += (uint64_t)sl->len[ODD_STATE] * sl->len[EVEN_STATE]; } @@ -1691,10 +1686,11 @@ static bool brute_force(void) // count number of states to go bucket_count = 0; - for (statelist_t *p = candidates; p != NULL; p = p->next) { + for (statelist_t *p = candidates; p != NULL && bucket_count < 128; p = p->next) { buckets[bucket_count] = p; bucket_count++; } + buckets[bucket_count] = NULL; #ifndef __WIN32 thread_count = sysconf(_SC_NPROCESSORS_CONF); @@ -1787,8 +1783,10 @@ int mfnestedhard(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBloc if (time1 > 0) PrintAndLog("Time for generating key candidates list: %1.0f seconds", ((float)time1)/CLOCKS_PER_SEC); - if (cracking) + if (cracking || known_target_key != -1) { brute_force(); + } + } else { // acquire nonces. uint16_t is_OK = acquire_nonces(blockNo, keyType, key, trgBlockNo, trgKeyType, nonce_file_write, slow); if (is_OK != 0) {