FIX: @pwpiwi 's fixes for darkside / nested attack about the NACK/PRNG bugs.

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index 027703ec40497499482021d0ae6d4441dc46baf0..354b829c94b041c090ebfed7611d0507db91c21d 100644 (file)
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -2175,11 +2175,13 @@ void ReaderIso14443a(UsbCommand *c)
 // Therefore try in alternating directions.
 int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 
 // Therefore try in alternating directions.
 int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 

+       uint16_t i;
+       uint32_t nttmp1, nttmp2;
+

        if (nt1 == nt2) return 0;
 
        if (nt1 == nt2) return 0;
 

-       uint16_t i;
-       uint32_t nttmp1 = nt1;
-       uint32_t nttmp2 = nt2;
+       nttmp1 = nt1;
+       nttmp2 = nt2;

        
        for (i = 1; i < 32768; i++) {
                nttmp1 = prng_successor(nttmp1, 1);
        
        for (i = 1; i < 32768; i++) {
                nttmp1 = prng_successor(nttmp1, 1);


@@ -2198,27 +2200,28 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
 // Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime"
 // (article by Nicolas T. Courtois, 2009)
 //-----------------------------------------------------------------------------
 // Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime"
 // (article by Nicolas T. Courtois, 2009)
 //-----------------------------------------------------------------------------

-void ReaderMifare(bool first_try) {
+void ReaderMifare(bool first_try)
+{
+       // Mifare AUTH
+       uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
+       uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+       static uint8_t mf_nr_ar3;
+
+       uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE];
+       uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE];
+

        // free eventually allocated BigBuf memory. We want all for tracing.
        BigBuf_free();
        
        clear_trace();
        set_tracing(TRUE);
 
        // free eventually allocated BigBuf memory. We want all for tracing.
        BigBuf_free();
        
        clear_trace();
        set_tracing(TRUE);
 

-       // Mifare AUTH
-       uint8_t mf_auth[] = { 0x60,0x00,0xf5,0x7b };
-       uint8_t mf_nr_ar[8] = { 0x00 }; //{ 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01 };
-       static uint8_t mf_nr_ar3 = 0;
-
-       uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE] = { 0x00 };
-       uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE] = { 0x00 };
-

        byte_t nt_diff = 0;
        uint8_t par[1] = {0};   // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
        static byte_t par_low = 0;
        bool led_on = TRUE;
        byte_t nt_diff = 0;
        uint8_t par[1] = {0};   // maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
        static byte_t par_low = 0;
        bool led_on = TRUE;

-       uint8_t uid[10] = {0x00};
-       //uint32_t cuid = 0x00;
+       uint8_t uid[10]  ={0};
+       uint32_t cuid;

 
        uint32_t nt = 0;
        uint32_t previous_nt = 0;
 
        uint32_t nt = 0;
        uint32_t previous_nt = 0;


@@ -2233,8 +2236,6 @@ void ReaderMifare(bool first_try) {
        uint16_t consecutive_resyncs = 0;
        int isOK = 0;
 
        uint16_t consecutive_resyncs = 0;
        int isOK = 0;
 

-       int numWrongDistance = 0;
-       

        if (first_try) { 
                mf_nr_ar3 = 0;
                iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
        if (first_try) { 
                mf_nr_ar3 = 0;
                iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);


@@ -2254,22 +2255,23 @@ void ReaderMifare(bool first_try) {
        LED_A_ON();
        LED_B_OFF();
        LED_C_OFF();
        LED_A_ON();
        LED_B_OFF();
        LED_C_OFF();

-       LED_C_ON();     
+       
+
+       #define DARKSIDE_MAX_TRIES      32              // number of tries to sync on PRNG cycle. Then give up.
+       uint16_t unsuccessfull_tries = 0;

   
        for(uint16_t i = 0; TRUE; i++) {
                
   
        for(uint16_t i = 0; TRUE; i++) {
                

+               LED_C_ON();

                WDT_HIT();
 
                // Test if the action was cancelled
                WDT_HIT();
 
                // Test if the action was cancelled

-               if(BUTTON_PRESS()) break;
-               
-               if (numWrongDistance > 1000) {
-                       isOK = 0;
+               if(BUTTON_PRESS()) {
+                       isOK = -1;

                        break;
                }
                
                        break;
                }
                

-               //if(!iso14443a_select_card(uid, NULL, &cuid)) {
-               if(!iso14443a_select_card(uid, NULL, NULL)) {
+               if(!iso14443a_select_card(uid, NULL, &cuid)) {

                        if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Can't select card");
                        continue;
                }
                        if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Can't select card");
                        continue;
                }


@@ -2303,14 +2305,15 @@ void ReaderMifare(bool first_try) {
                                nt_attacked = nt;
                        }
                        else {
                                nt_attacked = nt;
                        }
                        else {

-                               
-                               // invalid nonce received, try again
-                               if (nt_distance == -99999) { 
-                                       numWrongDistance++;
-                                       if (MF_DBGLEVEL >= 3) Dbprintf("The two nonces has invalid distance, tag could have good PRNG\n");
-                                       continue;
+                               if (nt_distance == -99999) { // invalid nonce received
+                                       unsuccessfull_tries++;
+                                       if (!nt_attacked && unsuccessfull_tries > DARKSIDE_MAX_TRIES) {
+                                               isOK = -3;              // Card has an unpredictable PRNG. Give up      
+                                               break;
+                                       } else {
+                                               continue;               // continue trying...
+                                       }

                                }
                                }

-                               

                                sync_cycles = (sync_cycles - nt_distance);
                                if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);
                                continue;
                                sync_cycles = (sync_cycles - nt_distance);
                                if (MF_DBGLEVEL >= 3) Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);
                                continue;


@@ -2319,7 +2322,7 @@ void ReaderMifare(bool first_try) {
 
                if ((nt != nt_attacked) && nt_attacked) {       // we somehow lost sync. Try to catch up again...
                        catch_up_cycles = -dist_nt(nt_attacked, nt);
 
                if ((nt != nt_attacked) && nt_attacked) {       // we somehow lost sync. Try to catch up again...
                        catch_up_cycles = -dist_nt(nt_attacked, nt);

-                       if (catch_up_cycles >= 99999) {                 // invalid nonce received. Don't resync on that one.
+                       if (catch_up_cycles == 99999) {                 // invalid nonce received. Don't resync on that one.

                                catch_up_cycles = 0;
                                continue;
                        }
                                catch_up_cycles = 0;
                                continue;
                        }


@@ -2371,12 +2374,17 @@ void ReaderMifare(bool first_try) {
                        if (nt_diff == 0 && first_try)
                        {
                                par[0]++;
                        if (nt_diff == 0 && first_try)
                        {
                                par[0]++;

+                               if (par[0] == 0x00) {           // tried all 256 possible parities without success. Card doesn't send NACK.
+                                       isOK = -2;
+                                       break;
+                               }

                        } else {
                                par[0] = ((par[0] & 0x1F) + 1) | par_low;
                        }
                }
        }
 
                        } else {
                                par[0] = ((par[0] & 0x1F) + 1) | par_low;
                        }
                }
        }
 

+

        mf_nr_ar[3] &= 0x1F;
        
        byte_t buf[28] = {0x00};
        mf_nr_ar[3] &= 0x1F;
        
        byte_t buf[28] = {0x00};

diff --git a/armsrc/mifarecmd.c b/armsrc/mifarecmd.c
index 5d10ad8161c2a97227ff9fbd91b728d87bfb68a9..b9f8e81efe49a587617c961b6aab741c0260fee1 100644 (file)
--- a/armsrc/mifarecmd.c
+++ b/armsrc/mifarecmd.c
@@ -16,7 +16,6 @@
 #include "mifarecmd.h"\r
 #include "apps.h"\r
 #include "util.h"\r
 #include "mifarecmd.h"\r
 #include "apps.h"\r
 #include "util.h"\r

-\r

 #include "crc.h"\r
 \r
 //-----------------------------------------------------------------------------\r
 #include "crc.h"\r
 \r
 //-----------------------------------------------------------------------------\r


@@ -641,6 +640,9 @@ void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t calibrate, uint8_t *dat
 \r
 \r
        // statistics on nonce distance\r
 \r
 \r
        // statistics on nonce distance\r

+       int16_t isOK = 0;\r
+       #define NESTED_MAX_TRIES 12\r
+       uint16_t unsuccessfull_tries = 0;\r

        if (calibrate) {        // for first call only. Otherwise reuse previous calibration\r
                LED_B_ON();\r
                WDT_HIT();\r
        if (calibrate) {        // for first call only. Otherwise reuse previous calibration\r
                LED_B_ON();\r
                WDT_HIT();\r


@@ -651,6 +653,12 @@ void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t calibrate, uint8_t *dat
                \r
                for (rtr = 0; rtr < 17; rtr++) {\r
 \r
                \r
                for (rtr = 0; rtr < 17; rtr++) {\r
 \r

+                       // Test if the action was cancelled\r
+                       if(BUTTON_PRESS()) {\r
+                               isOK = -2;\r
+                               break;\r
+                       }\r
+\r

                        // prepare next select. No need to power down the card.\r
                        if(mifare_classic_halt(pcs, cuid)) {\r
                                if (MF_DBGLEVEL >= 1)   Dbprintf("Nested: Halt error");\r
                        // prepare next select. No need to power down the card.\r
                        if(mifare_classic_halt(pcs, cuid)) {\r
                                if (MF_DBGLEVEL >= 1)   Dbprintf("Nested: Halt error");\r


@@ -698,14 +706,17 @@ void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t calibrate, uint8_t *dat
                                        delta_time = auth2_time - auth1_time + 32;  // allow some slack for proper timing\r
                                }\r
                                if (MF_DBGLEVEL >= 3) Dbprintf("Nested: calibrating... ntdist=%d", i);\r
                                        delta_time = auth2_time - auth1_time + 32;  // allow some slack for proper timing\r
                                }\r
                                if (MF_DBGLEVEL >= 3) Dbprintf("Nested: calibrating... ntdist=%d", i);\r

+                       } else {\r
+                               unsuccessfull_tries++;\r
+                               if (unsuccessfull_tries > NESTED_MAX_TRIES) {   // card isn't vulnerable to nested attack (random numbers are not predictable)\r
+                                       isOK = -3;\r
+                               }\r

                        }\r
                }\r
                        }\r
                }\r

-               \r
-               if (rtr <= 1)   return;\r

 \r
                davg = (davg + (rtr - 1)/2) / (rtr - 1);\r
                \r
 \r
                davg = (davg + (rtr - 1)/2) / (rtr - 1);\r
                \r

-               if (MF_DBGLEVEL >= 3) Dbprintf("min=%d max=%d avg=%d, delta_time=%d", dmin, dmax, davg, delta_time);\r
+               if (MF_DBGLEVEL >= 3) Dbprintf("rtr=%d isOK=%d min=%d max=%d avg=%d, delta_time=%d", rtr, isOK, dmin, dmax, davg, delta_time);\r

 \r
                dmin = davg - 2;\r
                dmax = davg + 2;\r
 \r
                dmin = davg - 2;\r
                dmax = davg + 2;\r


@@ -718,7 +729,7 @@ void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t calibrate, uint8_t *dat
        LED_C_ON();\r
 \r
        //  get crypted nonces for target sector\r
        LED_C_ON();\r
 \r
        //  get crypted nonces for target sector\r

-       for(i=0; i < 2; i++) { // look for exactly two different nonces\r
+       for(i=0; i < 2 && !isOK; i++) { // look for exactly two different nonces\r

 \r
                target_nt[i] = 0;\r
                while(target_nt[i] == 0) { // continue until we have an unambiguous nonce\r
 \r
                target_nt[i] = 0;\r
                while(target_nt[i] == 0) { // continue until we have an unambiguous nonce\r


@@ -796,7 +807,7 @@ void MifareNested(uint32_t arg0, uint32_t arg1, uint32_t calibrate, uint8_t *dat
        memcpy(buf+16, &target_ks[1], 4);\r
        \r
        LED_B_ON();\r
        memcpy(buf+16, &target_ks[1], 4);\r
        \r
        LED_B_ON();\r

-       cmd_send(CMD_ACK, 0, 2, targetBlockNo + (targetKeyType * 0x100), buf, sizeof(buf));\r
+       cmd_send(CMD_ACK, isOK, 0, targetBlockNo + (targetKeyType * 0x100), buf, sizeof(buf));\r

        LED_B_OFF();\r
 \r
        if (MF_DBGLEVEL >= 3)   DbpString("NESTED FINISHED");\r
        LED_B_OFF();\r
 \r
        if (MF_DBGLEVEL >= 3)   DbpString("NESTED FINISHED");\r

diff --git a/client/cmdhfmf.c b/client/cmdhfmf.c
index 809c623acff06c3d05fad362c48aa19503e25fdb..58d2061af30cfc7f15bd59d39217da93dfb3746e 100644 (file)
--- a/client/cmdhfmf.c
+++ b/client/cmdhfmf.c
@@ -18,7 +18,7 @@ int CmdHF14AMifare(const char *Cmd)
        uint32_t uid = 0;\r
        uint32_t nt = 0, nr = 0;\r
        uint64_t par_list = 0, ks_list = 0, r_key = 0;\r
        uint32_t uid = 0;\r
        uint32_t nt = 0, nr = 0;\r
        uint64_t par_list = 0, ks_list = 0, r_key = 0;\r

-       uint8_t isOK = 0;\r
+       int16_t isOK = 0;\r

        uint8_t keyBlock[8] = {0};\r
 \r
        UsbCommand c = {CMD_READER_MIFARE, {true, 0, 0}};\r
        uint8_t keyBlock[8] = {0};\r
 \r
        UsbCommand c = {CMD_READER_MIFARE, {true, 0, 0}};\r


@@ -26,7 +26,7 @@ int CmdHF14AMifare(const char *Cmd)
        // message\r
        printf("-------------------------------------------------------------------------\n");\r
        printf("Executing command. Expected execution time: 25sec on average  :-)\n");\r
        // message\r
        printf("-------------------------------------------------------------------------\n");\r
        printf("Executing command. Expected execution time: 25sec on average  :-)\n");\r

-       printf("Press the key on the proxmark3 device to abort both proxmark3 and client.\n");\r
+       printf("Press button on the proxmark3 device to abort both proxmark3 and client.\n");\r

        printf("-------------------------------------------------------------------------\n");\r
 \r
        \r
        printf("-------------------------------------------------------------------------\n");\r
 \r
        \r


@@ -49,14 +49,19 @@ start:
                \r
                UsbCommand resp;\r
                if (WaitForResponseTimeout(CMD_ACK,&resp,1000)) {\r
                \r
                UsbCommand resp;\r
                if (WaitForResponseTimeout(CMD_ACK,&resp,1000)) {\r

-                       isOK  = resp.arg[0] & 0xff;\r
+                       isOK  = resp.arg[0];\r

                        uid = (uint32_t)bytes_to_num(resp.d.asBytes +  0, 4);\r
                        nt =  (uint32_t)bytes_to_num(resp.d.asBytes +  4, 4);\r
                        par_list = bytes_to_num(resp.d.asBytes +  8, 8);\r
                        ks_list = bytes_to_num(resp.d.asBytes +  16, 8);\r
                        nr = bytes_to_num(resp.d.asBytes + 24, 4);\r
                        printf("\n\n");\r
                        uid = (uint32_t)bytes_to_num(resp.d.asBytes +  0, 4);\r
                        nt =  (uint32_t)bytes_to_num(resp.d.asBytes +  4, 4);\r
                        par_list = bytes_to_num(resp.d.asBytes +  8, 8);\r
                        ks_list = bytes_to_num(resp.d.asBytes +  16, 8);\r
                        nr = bytes_to_num(resp.d.asBytes + 24, 4);\r
                        printf("\n\n");\r

-                       if (!isOK) PrintAndLog("Proxmark can't get statistic info. Execution aborted.\n");\r
+                       switch (isOK) {\r
+                               case -1 : PrintAndLog("Button pressed. Aborted.\n"); break;\r
+                               case -2 : PrintAndLog("Card is not vulnerable to Darkside attack (doesn't send NACK on authentication requests).\n"); break;\r
+                               case -3 : PrintAndLog("Card is not vulnerable to Darkside attack (its random number generator is not predictable).\n"); break;\r
+                               default: ;\r
+                       }\r

                        break;\r
                }\r
        }       \r
                        break;\r
                }\r
        }       \r


@@ -623,8 +628,14 @@ int CmdHF14AMfNested(const char *Cmd)
        \r
        if (cmdp == 'o') {\r
                PrintAndLog("--target block no:%3d, target key type:%c ", trgBlockNo, trgKeyType?'B':'A');\r
        \r
        if (cmdp == 'o') {\r
                PrintAndLog("--target block no:%3d, target key type:%c ", trgBlockNo, trgKeyType?'B':'A');\r

-               if (mfnested(blockNo, keyType, key, trgBlockNo, trgKeyType, keyBlock, true)) {\r
-                       PrintAndLog("Nested error.");\r
+               int16_t isOK = mfnested(blockNo, keyType, key, trgBlockNo, trgKeyType, keyBlock, true);\r
+               if (isOK) {\r
+                       switch (isOK) {\r
+                               case -1 : PrintAndLog("Error: No response from Proxmark.\n"); break;\r
+                               case -2 : PrintAndLog("Button pressed. Aborted.\n"); break;\r
+                               case -3 : PrintAndLog("Tag isn't vulnerable to Nested Attack (random numbers are not predictable).\n"); break;\r
+                               default : PrintAndLog("Unknown Error.\n");\r
+                       }\r

                        return 2;\r
                }\r
                key64 = bytes_to_num(keyBlock, 6);\r
                        return 2;\r
                }\r
                key64 = bytes_to_num(keyBlock, 6);\r


@@ -697,11 +708,17 @@ int CmdHF14AMfNested(const char *Cmd)
                                for (trgKeyType = 0; trgKeyType < 2; trgKeyType++) { \r
                                        if (e_sector[sectorNo].foundKey[trgKeyType]) continue;\r
                                        PrintAndLog("-----------------------------------------------");\r
                                for (trgKeyType = 0; trgKeyType < 2; trgKeyType++) { \r
                                        if (e_sector[sectorNo].foundKey[trgKeyType]) continue;\r
                                        PrintAndLog("-----------------------------------------------");\r

-                                       if(mfnested(blockNo, keyType, key, FirstBlockOfSector(sectorNo), trgKeyType, keyBlock, calibrate)) {\r
-                                               PrintAndLog("Nested error.\n");\r
+                                       int16_t isOK = mfnested(blockNo, keyType, key, FirstBlockOfSector(sectorNo), trgKeyType, keyBlock, calibrate);\r
+                                       if(isOK) {\r
+                                               switch (isOK) {\r
+                                                       case -1 : PrintAndLog("Error: No response from Proxmark.\n"); break;\r
+                                                       case -2 : PrintAndLog("Button pressed. Aborted.\n"); break;\r
+                                                       case -3 : PrintAndLog("Tag isn't vulnerable to Nested Attack (random numbers are not predictable).\n"); break;\r
+                                                       default : PrintAndLog("Unknown Error.\n");\r
+                                               }\r

                                                free(e_sector);\r
                                                free(e_sector);\r

-                                               return 2;                                       }\r
-                                       else {\r
+                                               return 2;\r
+                                       } else {\r

                                                calibrate = false;\r
                                        }\r
                                        \r
                                                calibrate = false;\r
                                        }\r
                                        \r

diff --git a/client/mifarehost.c b/client/mifarehost.c
index d754b06b4a1a01dd589c6523bc354fdd0c99566d..b18450cf3550a6ae3417ec88714c06ae4651b802 100644 (file)
--- a/client/mifarehost.c
+++ b/client/mifarehost.c
@@ -71,9 +71,10 @@ void* nested_worker_thread(void *arg)
 \r
 int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t * resultKey, bool calibrate) \r
 {\r
 \r
 int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t * resultKey, bool calibrate) \r
 {\r

-       uint16_t i, len;\r
+       uint16_t i;\r

        uint32_t uid;\r
        UsbCommand resp;\r
        uint32_t uid;\r
        UsbCommand resp;\r

+\r

        StateList_t statelists[2];\r
        struct Crypto1State *p1, *p2, *p3, *p4;\r
        \r
        StateList_t statelists[2];\r
        struct Crypto1State *p1, *p2, *p3, *p4;\r
        \r


@@ -84,26 +85,24 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
        memcpy(c.d.asBytes, key, 6);\r
        SendCommand(&c);\r
 \r
        memcpy(c.d.asBytes, key, 6);\r
        SendCommand(&c);\r
 \r

-       if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {\r
-               len = resp.arg[1];\r
-               if (len == 2) { \r
+       if (!WaitForResponseTimeout(CMD_ACK, &resp, 1500)) {\r
+               return -1;\r
+       }\r
+\r
+       if (resp.arg[0]) {\r
+               return resp.arg[0];  // error during nested\r
+       }\r
+               \r

                        memcpy(&uid, resp.d.asBytes, 4);\r
                        memcpy(&uid, resp.d.asBytes, 4);\r

-                       PrintAndLog("uid:%08x len=%d trgbl=%d trgkey=%x", uid, len, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8);\r
+       PrintAndLog("uid:%08x trgbl=%d trgkey=%x", uid, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8);\r

                        \r
                        for (i = 0; i < 2; i++) {\r
                                statelists[i].blockNo = resp.arg[2] & 0xff;\r
                                statelists[i].keyType = (resp.arg[2] >> 8) & 0xff;\r
                                statelists[i].uid = uid;\r
                        \r
                        for (i = 0; i < 2; i++) {\r
                                statelists[i].blockNo = resp.arg[2] & 0xff;\r
                                statelists[i].keyType = (resp.arg[2] >> 8) & 0xff;\r
                                statelists[i].uid = uid;\r

-\r

                                memcpy(&statelists[i].nt,  (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4);\r
                                memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4);\r
                        }\r
                                memcpy(&statelists[i].nt,  (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4);\r
                                memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4);\r
                        }\r

-               }\r
-               else {\r
-                       PrintAndLog("Got 0 keys from proxmark."); \r
-                       return 1;\r
-               }\r
-       }\r

        \r
        // calc keys\r
        \r
        \r
        // calc keys\r
        \r