From 360caababff8eaed758d3d32864435185fd36eed Mon Sep 17 00:00:00 2001 From: iceman1001 Date: Mon, 7 Nov 2016 22:41:18 +0100 Subject: [PATCH] FIX: decrease 2^39 -> 2^38. its a big searchspace anyway. FIX: changed output and rearranged collecting nonces logic. Still problems with "hard" keys, the device stops responding after a "bruteforce" / "generate_candidates" call.. Very strange. shouldnt' --- client/cmdhfmfhard.c | 147 ++++++++++++++++--------------------------- 1 file changed, 53 insertions(+), 94 deletions(-) diff --git a/client/cmdhfmfhard.c b/client/cmdhfmfhard.c index a6b9ebf1..dcf454c5 100644 --- a/client/cmdhfmfhard.c +++ b/client/cmdhfmfhard.c @@ -19,7 +19,7 @@ #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 NONCES_THRESHOLD 5000 // every N nonces check if we can crack the key -#define CRACKING_THRESHOLD 39.00f // as 2^39 +#define CRACKING_THRESHOLD 38.00f // as 2^38 #define END_OF_LIST_MARKER 0xFFFFFFFF @@ -292,7 +292,6 @@ static float sum_probability(uint16_t K, uint16_t n, uint16_t k) return(p_T_is_k_when_S_is_K * p_S_is_K / p_T_is_k); } - static inline uint_fast8_t common_bits(uint_fast8_t bytes_diff) { static const uint_fast8_t common_bits_LUT[256] = { @@ -757,30 +756,34 @@ static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_ uint32_t idx = 1; FILE *fnonces = NULL; UsbCommand resp; - field_off = false; - + UsbCommand c = {CMD_MIFARE_ACQUIRE_ENCRYPTED_NONCES, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, 0}}; + memcpy(c.d.asBytes, key, 6); + printf("Acquiring nonces...\n"); - do { flags = 0; flags |= initialize ? 0x0001 : 0; flags |= slow ? 0x0002 : 0; 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); - + c.arg[2] = flags; clearCommandBuffer(); SendCommand(&c); if (field_off) break; - - if (initialize) { - if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) return 1; - if (resp.arg[0]) return resp.arg[0]; // error during nested_hard + if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) { + if (fnonces) fclose(fnonces); + return 1; + } + if (resp.arg[0]) { + if (fnonces) fclose(fnonces); + return resp.arg[0]; // error during nested_hard + } + + if (initialize) { + // global var CUID cuid = resp.arg[1]; - // PrintAndLog("Acquiring nonces for CUID 0x%08x", cuid); if (nonce_file_write && fnonces == NULL) { if ((fnonces = fopen("nonces.bin","wb")) == NULL) { PrintAndLog("Could not create file nonces.bin"); @@ -793,45 +796,43 @@ static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_ fwrite(&trgKeyType, 1, 1, fnonces); fflush(fnonces); } + initialize = false; } - - if (!initialize) { - uint32_t nt_enc1, nt_enc2; - uint8_t par_enc; - uint16_t num_acquired_nonces = resp.arg[2]; - uint8_t *bufp = resp.d.asBytes; - for (uint16_t i = 0; i < num_acquired_nonces; i+=2) { - nt_enc1 = bytes_to_num(bufp, 4); - nt_enc2 = bytes_to_num(bufp+4, 4); - par_enc = bytes_to_num(bufp+8, 1); - - //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4); - total_added_nonces += add_nonce(nt_enc1, par_enc >> 4); - //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f); - total_added_nonces += add_nonce(nt_enc2, par_enc & 0x0f); - - if (nonce_file_write && fnonces) { - fwrite(bufp, 1, 9, fnonces); - fflush(fnonces); - } - - bufp += 9; + + uint32_t nt_enc1, nt_enc2; + uint8_t par_enc; + uint16_t num_acquired_nonces = resp.arg[2]; + uint8_t *bufp = resp.d.asBytes; + for (uint16_t i = 0; i < num_acquired_nonces; i+=2) { + nt_enc1 = bytes_to_num(bufp, 4); + nt_enc2 = bytes_to_num(bufp+4, 4); + par_enc = bytes_to_num(bufp+8, 1); + + //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc1, par_enc >> 4); + total_added_nonces += add_nonce(nt_enc1, par_enc >> 4); + //printf("Encrypted nonce: %08x, encrypted_parity: %02x\n", nt_enc2, par_enc & 0x0f); + total_added_nonces += add_nonce(nt_enc2, par_enc & 0x0f); + + if (nonce_file_write && fnonces) { + fwrite(bufp, 1, 9, fnonces); + fflush(fnonces); } - - total_num_nonces += num_acquired_nonces; + bufp += 9; } + total_num_nonces += num_acquired_nonces; + + if (first_byte_num == 256) { - if (first_byte_num == 256 && !field_off) { - // printf("first_byte_num = %d, first_byte_Sum = %d\n", first_byte_num, first_byte_Sum); if (!filter_flip_checked) { Check_for_FilterFlipProperties(); filter_flip_checked = true; } num_good_first_bytes = estimate_second_byte_sum(); + if (total_num_nonces > next_fivehundred) { next_fivehundred = (total_num_nonces/500+1) * 500; - 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", + printf("Acquired %5d nonces (%5d/%5d with distinct bytes 0,1). #bytes with probability for correctly guessed Sum(a8) > %1.1f%%: %d\n", total_num_nonces, total_added_nonces, NONCES_THRESHOLD * idx, @@ -839,36 +840,15 @@ static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_ num_good_first_bytes); } - if (total_added_nonces >= (NONCES_THRESHOLD * idx)) - { - num_good_first_bytes = estimate_second_byte_sum(); - clock_t time1 = clock(); - bool cracking = generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess); - time1 = clock() - time1; - if (time1 > 0) PrintAndLog("Time for generating key candidates list: %1.0f seconds", ((float)time1)/CLOCKS_PER_SEC); - - if (cracking || known_target_key != -1) { - field_off = brute_force(); // switch off field with next SendCommand and then finish - } - - idx++; + if (total_added_nonces >= (NONCES_THRESHOLD * idx) && num_good_first_bytes > 0 ) { + bool cracking = generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess); + if (cracking || known_target_key != -1) { + field_off = brute_force(); // switch off field with next SendCommand and then finish } - } - - if (!initialize) { - if (!WaitForResponseTimeout(CMD_ACK, &resp, 3000)) { - if (fnonces) fclose(fnonces); - return 1; - } - - if (resp.arg[0]) { - if (fnonces) fclose(fnonces); - return resp.arg[0]; // error during nested_hard + idx++; } } - initialize = false; - } while (!finished); if (nonce_file_write && fnonces) @@ -1232,7 +1212,7 @@ static bool TestIfKeyExists(uint64_t key) uint32_t state_odd = pcs->odd & 0x00ffffff; uint32_t state_even = pcs->even & 0x00ffffff; //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); - + printf("Validating keysearch space\n"); uint64_t count = 0; for (statelist_t *p = candidates; p != NULL; p = p->next) { bool found_odd = false; @@ -1254,7 +1234,7 @@ static bool TestIfKeyExists(uint64_t key) } count += (p_odd - p->states[ODD_STATE]) * (p_even - p->states[EVEN_STATE]); if (found_odd && found_even) { - PrintAndLog("\nKey Found after testing %lld (2^%1.1f) out of %lld (2^%1.1f) keys. ", + PrintAndLog("Key Found after testing %llu (2^%1.1f) out of %lld (2^%1.1f) keys.", count, log(count)/log(2), maximum_states, @@ -1653,15 +1633,14 @@ static void* crack_states_thread(void* x){ return NULL; } -static bool brute_force(void) -{ +static bool brute_force(void) { + if (maximum_states == 0) return false; // prevent keyspace reduction error (2^-inf) + bool ret = false; if (known_target_key != -1) { PrintAndLog("Looking for known target key in remaining key space..."); ret = TestIfKeyExists(known_target_key); } else { - if (maximum_states == 0) return false; // prevent keyspace reduction error (2^-inf) - PrintAndLog("Brute force phase starting."); clock_t time1 = clock(); @@ -1713,20 +1692,15 @@ static bool brute_force(void) } time1 = clock() - time1; - if ( time1 < 0 ) time1 = -1; + PrintAndLog("\nTime for bruteforce %0.1f seconds.",((float)time1)/CLOCKS_PER_SEC); if (keys_found && TestIfKeyExists(foundkey)) { - PrintAndLog("Success! Found %u keys after %0.0f seconds", keys_found, ((float)time1)/CLOCKS_PER_SEC); PrintAndLog("\nFound key: %012"PRIx64"\n", foundkey); ret = true; - } else { - PrintAndLog("Fail! Tested %"PRIu32" states, in %0.0f seconds", total_states_tested, ((float)time1)/CLOCKS_PER_SEC); - } - + } // reset this counter for the next call nonces_to_bruteforce = 0; } - return ret; } @@ -1797,21 +1771,6 @@ int mfnestedhard(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBloc } //Tests(); - - //PrintAndLog(""); - //PrintAndLog("Sum(a0) = %d", first_byte_Sum); - // PrintAndLog("Best 10 first bytes: %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x, %02x", - // best_first_bytes[0], - // best_first_bytes[1], - // best_first_bytes[2], - // best_first_bytes[3], - // best_first_bytes[4], - // best_first_bytes[5], - // best_first_bytes[6], - // best_first_bytes[7], - // best_first_bytes[8], - // best_first_bytes[9] ); - free_nonces_memory(); free_statelist_cache(); free_candidates_memory(candidates); -- 2.39.2