X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/90e278d3daf11b501043d7ae628a25aeb0227420..1f065e1dad00ff5a63ebfedb8fbe04a9720bf2a6:/client/mifarehost.c?ds=sidebyside diff --git a/client/mifarehost.c b/client/mifarehost.c index 7633def3..c6c6877e 100644 --- a/client/mifarehost.c +++ b/client/mifarehost.c @@ -8,25 +8,234 @@ // mifare commands //----------------------------------------------------------------------------- +#include "mifarehost.h" + #include #include #include #include -#include "mifarehost.h" -#include "proxmark3.h" -// MIFARE -int compar_int(const void * a, const void * b) { +#include "crapto1/crapto1.h" +#include "proxmark3.h" +#include "usb_cmd.h" +#include "cmdmain.h" +#include "ui.h" +#include "util.h" +#include "iso14443crc.h" + +// mifare tracer flags used in mfTraceDecode() +#define TRACE_IDLE 0x00 +#define TRACE_AUTH1 0x01 +#define TRACE_AUTH2 0x02 +#define TRACE_AUTH_OK 0x03 +#define TRACE_READ_DATA 0x04 +#define TRACE_WRITE_OK 0x05 +#define TRACE_WRITE_DATA 0x06 +#define TRACE_ERROR 0xFF + + +static int compare_uint64(const void *a, const void *b) { // didn't work: (the result is truncated to 32 bits) - //return (*(uint64_t*)b - *(uint64_t*)a); + //return (*(int64_t*)b - *(int64_t*)a); // better: if (*(uint64_t*)b == *(uint64_t*)a) return 0; - else if (*(uint64_t*)b > *(uint64_t*)a) return 1; + else if (*(uint64_t*)b < *(uint64_t*)a) return 1; else return -1; } +// create the intersection (common members) of two sorted lists. Lists are terminated by -1. Result will be in list1. Number of elements is returned. +static uint32_t intersection(uint64_t *list1, uint64_t *list2) +{ + if (list1 == NULL || list2 == NULL) { + return 0; + } + uint64_t *p1, *p2, *p3; + p1 = p3 = list1; + p2 = list2; + + while ( *p1 != -1 && *p2 != -1 ) { + if (compare_uint64(p1, p2) == 0) { + *p3++ = *p1++; + p2++; + } + else { + while (compare_uint64(p1, p2) < 0) ++p1; + while (compare_uint64(p1, p2) > 0) ++p2; + } + } + *p3 = -1; + return p3 - list1; +} + + +// Darkside attack (hf mf mifare) +static uint32_t nonce2key(uint32_t uid, uint32_t nt, uint32_t nr, uint64_t par_info, uint64_t ks_info, uint64_t **keys) { + struct Crypto1State *states; + uint32_t i, pos, rr; //nr_diff; + uint8_t bt, ks3x[8], par[8][8]; + uint64_t key_recovered; + static uint64_t *keylist; + rr = 0; + + // Reset the last three significant bits of the reader nonce + nr &= 0xffffff1f; + + for (pos=0; pos<8; pos++) { + ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f; + bt = (par_info >> (pos*8)) & 0xff; + for (i=0; i<8; i++) { + par[7-pos][i] = (bt >> i) & 0x01; + } + } + + states = lfsr_common_prefix(nr, rr, ks3x, par, (par_info == 0)); + + if (states == NULL) { + *keys = NULL; + return 0; + } + + keylist = (uint64_t*)states; + + for (i = 0; keylist[i]; i++) { + lfsr_rollback_word(states+i, uid^nt, 0); + crypto1_get_lfsr(states+i, &key_recovered); + keylist[i] = key_recovered; + } + keylist[i] = -1; + + *keys = keylist; + return i; +} + + +int mfDarkside(uint64_t *key) +{ + uint32_t uid = 0; + uint32_t nt = 0, nr = 0; + uint64_t par_list = 0, ks_list = 0; + uint64_t *keylist = NULL, *last_keylist = NULL; + uint32_t keycount = 0; + int16_t isOK = 0; + + UsbCommand c = {CMD_READER_MIFARE, {true, 0, 0}}; + + // message + printf("-------------------------------------------------------------------------\n"); + printf("Executing command. Expected execution time: 25sec on average\n"); + printf("Press button on the proxmark3 device to abort both proxmark3 and client.\n"); + printf("-------------------------------------------------------------------------\n"); + + + while (true) { + clearCommandBuffer(); + SendCommand(&c); + + //flush queue + while (ukbhit()) { + int c = getchar(); (void) c; + } + + // wait cycle + while (true) { + printf("."); + fflush(stdout); + if (ukbhit()) { + return -5; + break; + } + + UsbCommand resp; + if (WaitForResponseTimeout(CMD_ACK, &resp, 1000)) { + isOK = resp.arg[0]; + if (isOK < 0) { + return isOK; + } + uid = (uint32_t)bytes_to_num(resp.d.asBytes + 0, 4); + nt = (uint32_t)bytes_to_num(resp.d.asBytes + 4, 4); + par_list = bytes_to_num(resp.d.asBytes + 8, 8); + ks_list = bytes_to_num(resp.d.asBytes + 16, 8); + nr = bytes_to_num(resp.d.asBytes + 24, 4); + break; + } + } + + if (par_list == 0 && c.arg[0] == true) { + PrintAndLog("Parity is all zero. Most likely this card sends NACK on every failed authentication."); + PrintAndLog("Attack will take a few seconds longer because we need two consecutive successful runs."); + } + c.arg[0] = false; + + keycount = nonce2key(uid, nt, nr, par_list, ks_list, &keylist); + + if (keycount == 0) { + PrintAndLog("Key not found (lfsr_common_prefix list is null). Nt=%08x", nt); + PrintAndLog("This is expected to happen in 25%% of all cases. Trying again with a different reader nonce..."); + continue; + } + + qsort(keylist, keycount, sizeof(*keylist), compare_uint64); + keycount = intersection(last_keylist, keylist); + if (keycount == 0) { + free(last_keylist); + last_keylist = keylist; + continue; + } + + if (keycount > 1) { + PrintAndLog("Found %u possible keys. Trying to authenticate with each of them ...\n", keycount); + } else { + PrintAndLog("Found a possible key. Trying to authenticate...\n"); + } + + *key = -1; + uint8_t keyBlock[USB_CMD_DATA_SIZE]; + int max_keys = USB_CMD_DATA_SIZE/6; + for (int i = 0; i < keycount; i += max_keys) { + int size = keycount - i > max_keys ? max_keys : keycount - i; + for (int j = 0; j < size; j++) { + if (last_keylist == NULL) { + num_to_bytes(keylist[i*max_keys + j], 6, keyBlock); + } else { + num_to_bytes(last_keylist[i*max_keys + j], 6, keyBlock); + } + } + if (!mfCheckKeys(0, 0, false, size, keyBlock, key)) { + break; + } + } + + if (*key != -1) { + free(last_keylist); + free(keylist); + break; + } else { + PrintAndLog("Authentication failed. Trying again..."); + free(last_keylist); + last_keylist = keylist; + } + } + + return 0; +} + + +int mfCheckKeys (uint8_t blockNo, uint8_t keyType, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, uint64_t * key){ + + *key = 0; + + UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType&0xff)<<8)), clear_trace, keycnt}}; + memcpy(c.d.asBytes, keyBlock, 6 * keycnt); + SendCommand(&c); + + UsbCommand resp; + if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1; + if ((resp.arg[0] & 0xff) != 0x01) return 2; + *key = bytes_to_num(resp.d.asBytes, 6); + return 0; +} // Compare 16 Bits out of cryptostate int Compare16Bits(const void * a, const void * b) { @@ -35,7 +244,6 @@ int Compare16Bits(const void * a, const void * b) { else return -1; } - typedef struct { union { @@ -70,45 +278,39 @@ void* nested_worker_thread(void *arg) return statelist->head.slhead; } - - - -int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t * resultKey, bool calibrate) +int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *resultKey, bool calibrate) { - uint16_t i, len; + uint16_t i; uint32_t uid; UsbCommand resp; - StateList_t statelists[2]; struct Crypto1State *p1, *p2, *p3, *p4; // flush queue - WaitForResponseTimeout(CMD_ACK,NULL,100); + WaitForResponseTimeout(CMD_ACK, NULL, 100); UsbCommand c = {CMD_MIFARE_NESTED, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, calibrate}}; memcpy(c.d.asBytes, key, 6); SendCommand(&c); - if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) { - len = resp.arg[1]; - if (len == 2) { - memcpy(&uid, resp.d.asBytes, 4); - PrintAndLog("uid:%08x len=%d trgbl=%d trgkey=%x", uid, len, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8); - - for (i = 0; i < 2; i++) { - statelists[i].blockNo = resp.arg[2] & 0xff; - statelists[i].keyType = (resp.arg[2] >> 8) & 0xff; - statelists[i].uid = uid; + if (!WaitForResponseTimeout(CMD_ACK, &resp, 1500)) { + return -1; + } - memcpy(&statelists[i].nt, (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4); - memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4); - } - } - else { - PrintAndLog("Got 0 keys from proxmark."); - return 1; - } + if (resp.arg[0]) { + return resp.arg[0]; // error during nested + } + + memcpy(&uid, resp.d.asBytes, 4); + PrintAndLog("uid:%08x trgbl=%d trgkey=%x", uid, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8); + + for (i = 0; i < 2; i++) { + statelists[i].blockNo = resp.arg[2] & 0xff; + statelists[i].keyType = (resp.arg[2] >> 8) & 0xff; + statelists[i].uid = uid; + memcpy(&statelists[i].nt, (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4); + memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4); } // calc keys @@ -154,8 +356,8 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo while (Compare16Bits(p1, p2) == 1) p2++; } } - p3->even = 0; p3->odd = 0; - p4->even = 0; p4->odd = 0; + *(uint64_t*)p3 = -1; + *(uint64_t*)p4 = -1; statelists[0].len = p3 - statelists[0].head.slhead; statelists[1].len = p4 - statelists[1].head.slhead; statelists[0].tail.sltail=--p3; @@ -163,24 +365,9 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo // the statelists now contain possible keys. The key we are searching for must be in the // intersection of both lists. Create the intersection: - qsort(statelists[0].head.keyhead, statelists[0].len, sizeof(uint64_t), compar_int); - qsort(statelists[1].head.keyhead, statelists[1].len, sizeof(uint64_t), compar_int); - - uint64_t *p5, *p6, *p7; - p5 = p7 = statelists[0].head.keyhead; - p6 = statelists[1].head.keyhead; - while (p5 <= statelists[0].tail.keytail && p6 <= statelists[1].tail.keytail) { - if (compar_int(p5, p6) == 0) { - *p7++ = *p5++; - p6++; - } - else { - while (compar_int(p5, p6) == -1) p5++; - while (compar_int(p5, p6) == 1) p6++; - } - } - statelists[0].len = p7 - statelists[0].head.keyhead; - statelists[0].tail.keytail=--p7; + qsort(statelists[0].head.keyhead, statelists[0].len, sizeof(uint64_t), compare_uint64); + qsort(statelists[1].head.keyhead, statelists[1].len, sizeof(uint64_t), compare_uint64); + statelists[0].len = intersection(statelists[0].head.keyhead, statelists[1].head.keyhead); memset(resultKey, 0, 6); // The list may still contain several key candidates. Test each of them with mfCheckKeys @@ -190,7 +377,7 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo crypto1_get_lfsr(statelists[0].head.slhead + i, &key64); num_to_bytes(key64, 6, keyBlock); key64 = 0; - if (!mfCheckKeys(statelists[0].blockNo, statelists[0].keyType, 1, keyBlock, &key64)) { + if (!mfCheckKeys(statelists[0].blockNo, statelists[0].keyType, false, 1, keyBlock, &key64)) { num_to_bytes(key64, 6, resultKey); break; } @@ -202,21 +389,6 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo return 0; } -int mfCheckKeys (uint8_t blockNo, uint8_t keyType, uint8_t keycnt, uint8_t * keyBlock, uint64_t * key){ - - *key = 0; - - UsbCommand c = {CMD_MIFARE_CHKKEYS, {blockNo, keyType, keycnt}}; - memcpy(c.d.asBytes, keyBlock, 6 * keycnt); - SendCommand(&c); - - UsbCommand resp; - if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1; - if ((resp.arg[0] & 0xff) != 0x01) return 2; - *key = bytes_to_num(resp.d.asBytes, 6); - return 0; -} - // EMULATOR int mfEmlGetMem(uint8_t *data, int blockNum, int blocksCount) { @@ -238,30 +410,16 @@ int mfEmlSetMem(uint8_t *data, int blockNum, int blocksCount) { // "MAGIC" CARD -int mfCSetUID(uint8_t *uid, uint8_t *oldUID, int wantWipe) { - uint8_t block0[16]; - memset(block0, 0, 16); - memcpy(block0, uid, 4); - block0[4] = block0[0]^block0[1]^block0[2]^block0[3]; // Mifare UID BCC - // mifare classic SAK(byte 5) and ATQA(byte 6 and 7) - block0[5] = 0x88; - block0[6] = 0x04; - block0[7] = 0x00; - - return mfCSetBlock(0, block0, oldUID, wantWipe, CSETBLOCK_SINGLE_OPER); -} - -int mfCSetBlock(uint8_t blockNo, uint8_t *data, uint8_t *uid, int wantWipe, uint8_t params) { +int mfCGetBlock(uint8_t blockNo, uint8_t *data, uint8_t params) { uint8_t isOK = 0; - UsbCommand c = {CMD_MIFARE_EML_CSETBLOCK, {wantWipe, params & (0xFE | (uid == NULL ? 0:1)), blockNo}}; - memcpy(c.d.asBytes, data, 16); + UsbCommand c = {CMD_MIFARE_CGETBLOCK, {params, 0, blockNo}}; SendCommand(&c); UsbCommand resp; if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) { isOK = resp.arg[0] & 0xff; - if (uid != NULL) memcpy(uid, resp.d.asBytes, 4); + memcpy(data, resp.d.asBytes, 16); if (!isOK) return 2; } else { PrintAndLog("Command execute timeout"); @@ -270,17 +428,20 @@ int mfCSetBlock(uint8_t blockNo, uint8_t *data, uint8_t *uid, int wantWipe, uint return 0; } -int mfCGetBlock(uint8_t blockNo, uint8_t *data, uint8_t params) { - uint8_t isOK = 0; +int mfCSetBlock(uint8_t blockNo, uint8_t *data, uint8_t *uid, bool wantWipe, uint8_t params) { - UsbCommand c = {CMD_MIFARE_EML_CGETBLOCK, {params, 0, blockNo}}; + uint8_t isOK = 0; + UsbCommand c = {CMD_MIFARE_CSETBLOCK, {wantWipe, params & (0xFE | (uid == NULL ? 0:1)), blockNo}}; + memcpy(c.d.asBytes, data, 16); SendCommand(&c); UsbCommand resp; if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) { isOK = resp.arg[0] & 0xff; - memcpy(data, resp.d.asBytes, 16); - if (!isOK) return 2; + if (uid != NULL) + memcpy(uid, resp.d.asBytes, 4); + if (!isOK) + return 2; } else { PrintAndLog("Command execute timeout"); return 1; @@ -288,15 +449,43 @@ int mfCGetBlock(uint8_t blockNo, uint8_t *data, uint8_t params) { return 0; } +int mfCSetUID(uint8_t *uid, uint8_t *atqa, uint8_t *sak, uint8_t *oldUID, bool wantWipe) { + uint8_t oldblock0[16] = {0x00}; + uint8_t block0[16] = {0x00}; + + int old = mfCGetBlock(0, oldblock0, CSETBLOCK_SINGLE_OPER); + if (old == 0) { + memcpy(block0, oldblock0, 16); + PrintAndLog("old block 0: %s", sprint_hex(block0,16)); + } else { + PrintAndLog("Couldn't get old data. Will write over the last bytes of Block 0."); + } + + // fill in the new values + // UID + memcpy(block0, uid, 4); + // Mifare UID BCC + block0[4] = block0[0]^block0[1]^block0[2]^block0[3]; + // mifare classic SAK(byte 5) and ATQA(byte 6 and 7, reversed) + if (sak!=NULL) + block0[5]=sak[0]; + if (atqa!=NULL) { + block0[6]=atqa[1]; + block0[7]=atqa[0]; + } + PrintAndLog("new block 0: %s", sprint_hex(block0,16)); + return mfCSetBlock(0, block0, oldUID, wantWipe, CSETBLOCK_SINGLE_OPER); +} + // SNIFFER // constants static uint8_t trailerAccessBytes[4] = {0x08, 0x77, 0x8F, 0x00}; // variables -char logHexFileName[200] = {0x00}; +char logHexFileName[FILE_PATH_SIZE] = {0x00}; static uint8_t traceCard[4096] = {0x00}; -static char traceFileName[200] = {0}; +static char traceFileName[FILE_PATH_SIZE] = {0x00}; static int traceState = TRACE_IDLE; static uint8_t traceCurBlock = 0; static uint8_t traceCurKey = 0; @@ -310,12 +499,9 @@ uint32_t ks3; uint32_t uid; // serial number uint32_t nt; // tag challenge -uint32_t nt_par; uint32_t nr_enc; // encrypted reader challenge uint32_t ar_enc; // encrypted reader response -uint32_t nr_ar_par; uint32_t at_enc; // encrypted tag response -uint32_t at_par; int isTraceCardEmpty(void) { return ((traceCard[0] == 0) && (traceCard[1] == 0) && (traceCard[2] == 0) && (traceCard[3] == 0)); @@ -332,31 +518,55 @@ int isBlockTrailer(int blockN) { return ((blockN & 0x03) == 0x03); } +int saveTraceCard(void) { + FILE * f; + + if ((!strlen(traceFileName)) || (isTraceCardEmpty())) return 0; + + f = fopen(traceFileName, "w+"); + if ( !f ) return 1; + + for (int i = 0; i < 64; i++) { // blocks + for (int j = 0; j < 16; j++) // bytes + fprintf(f, "%02x", *(traceCard + i * 16 + j)); + fprintf(f,"\n"); + } + fclose(f); + return 0; +} + int loadTraceCard(uint8_t *tuid) { FILE * f; - char buf[64]; - uint8_t buf8[64]; + char buf[64] = {0x00}; + uint8_t buf8[64] = {0x00}; int i, blockNum; - if (!isTraceCardEmpty()) saveTraceCard(); + if (!isTraceCardEmpty()) + saveTraceCard(); + memset(traceCard, 0x00, 4096); memcpy(traceCard, tuid + 3, 4); + FillFileNameByUID(traceFileName, tuid, ".eml", 7); f = fopen(traceFileName, "r"); if (!f) return 1; blockNum = 0; + while(!feof(f)){ + memset(buf, 0, sizeof(buf)); if (fgets(buf, sizeof(buf), f) == NULL) { - PrintAndLog("File reading error."); + PrintAndLog("File reading error."); + fclose(f); return 2; - } + } if (strlen(buf) < 32){ if (feof(f)) break; PrintAndLog("File content error. Block data must include 32 HEX symbols"); + fclose(f); return 2; } for (i = 0; i < 32; i += 2) @@ -371,28 +581,16 @@ int loadTraceCard(uint8_t *tuid) { return 0; } -int saveTraceCard(void) { - FILE * f; - - if ((!strlen(traceFileName)) || (isTraceCardEmpty())) return 0; - - f = fopen(traceFileName, "w+"); - for (int i = 0; i < 64; i++) { // blocks - for (int j = 0; j < 16; j++) // bytes - fprintf(f, "%02x", *(traceCard + i * 16 + j)); - fprintf(f,"\n"); - } - fclose(f); - - return 0; -} - int mfTraceInit(uint8_t *tuid, uint8_t *atqa, uint8_t sak, bool wantSaveToEmlFile) { - if (traceCrypto1) crypto1_destroy(traceCrypto1); + if (traceCrypto1) + crypto1_destroy(traceCrypto1); + traceCrypto1 = NULL; - if (wantSaveToEmlFile) loadTraceCard(tuid); + if (wantSaveToEmlFile) + loadTraceCard(tuid); + traceCard[4] = traceCard[0] ^ traceCard[1] ^ traceCard[2] ^ traceCard[3]; traceCard[5] = sak; memcpy(&traceCard[6], atqa, 2); @@ -422,7 +620,7 @@ void mf_crypto1_decrypt(struct Crypto1State *pcs, uint8_t *data, int len, bool i } -int mfTraceDecode(uint8_t *data_src, int len, uint32_t parity, bool wantSaveToEmlFile) { +int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) { uint8_t data[64]; if (traceState == TRACE_ERROR) return 1; @@ -497,7 +695,7 @@ int mfTraceDecode(uint8_t *data_src, int len, uint32_t parity, bool wantSaveToEm break; case TRACE_WRITE_OK: - if ((len == 1) && (data[0] = 0x0a)) { + if ((len == 1) && (data[0] == 0x0a)) { traceState = TRACE_WRITE_DATA; return 0; @@ -523,9 +721,7 @@ int mfTraceDecode(uint8_t *data_src, int len, uint32_t parity, bool wantSaveToEm case TRACE_AUTH1: if (len == 4) { traceState = TRACE_AUTH2; - nt = bytes_to_num(data, 4); - nt_par = parity; return 0; } else { traceState = TRACE_ERROR; @@ -539,7 +735,6 @@ int mfTraceDecode(uint8_t *data_src, int len, uint32_t parity, bool wantSaveToEm nr_enc = bytes_to_num(data, 4); ar_enc = bytes_to_num(data + 4, 4); - nr_ar_par = parity; return 0; } else { traceState = TRACE_ERROR; @@ -552,26 +747,16 @@ int mfTraceDecode(uint8_t *data_src, int len, uint32_t parity, bool wantSaveToEm traceState = TRACE_IDLE; at_enc = bytes_to_num(data, 4); - at_par = parity; // decode key here) - if (!traceCrypto1) { - ks2 = ar_enc ^ prng_successor(nt, 64); - ks3 = at_enc ^ prng_successor(nt, 96); - revstate = lfsr_recovery64(ks2, ks3); - lfsr_rollback_word(revstate, 0, 0); - lfsr_rollback_word(revstate, 0, 0); - lfsr_rollback_word(revstate, nr_enc, 1); - lfsr_rollback_word(revstate, uid ^ nt, 0); - }else{ - ks2 = ar_enc ^ prng_successor(nt, 64); - ks3 = at_enc ^ prng_successor(nt, 96); - revstate = lfsr_recovery64(ks2, ks3); - lfsr_rollback_word(revstate, 0, 0); - lfsr_rollback_word(revstate, 0, 0); - lfsr_rollback_word(revstate, nr_enc, 1); - lfsr_rollback_word(revstate, uid ^ nt, 0); - } + ks2 = ar_enc ^ prng_successor(nt, 64); + ks3 = at_enc ^ prng_successor(nt, 96); + revstate = lfsr_recovery64(ks2, ks3); + lfsr_rollback_word(revstate, 0, 0); + lfsr_rollback_word(revstate, 0, 0); + lfsr_rollback_word(revstate, nr_enc, 1); + lfsr_rollback_word(revstate, uid ^ nt, 0); + crypto1_get_lfsr(revstate, &lfsr); printf("key> %x%x\n", (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF)); AddLogUint64(logHexFileName, "key> ", lfsr); @@ -615,3 +800,23 @@ int mfTraceDecode(uint8_t *data_src, int len, uint32_t parity, bool wantSaveToEm return 0; } + +int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data, int len){ + /* + uint32_t nt; // tag challenge + uint32_t ar_enc; // encrypted reader response + uint32_t at_enc; // encrypted tag response + */ + if (traceCrypto1) { + crypto1_destroy(traceCrypto1); + } + ks2 = ar_enc ^ prng_successor(nt, 64); + ks3 = at_enc ^ prng_successor(nt, 96); + traceCrypto1 = lfsr_recovery64(ks2, ks3); + + mf_crypto1_decrypt(traceCrypto1, data, len, 0); + + PrintAndLog("Decrypted data: [%s]", sprint_hex(data,len) ); + crypto1_destroy(traceCrypto1); + return 0; +}