]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/iso14443a.c
hf mf mifare:
[proxmark3-svn] / armsrc / iso14443a.c
index a7102168e09d75522e1e35ac02526136a464a57d..0431876eca41eb756342de78d8a3e58a75711f78 100644 (file)
@@ -141,16 +141,40 @@ const uint8_t OddByteParity[256] = {
   1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
 };
 
+
 void iso14a_set_trigger(bool enable) {
        trigger = enable;
 }
 
 
-
 void iso14a_set_timeout(uint32_t timeout) {
        iso14a_timeout = timeout;
+       if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", iso14a_timeout, iso14a_timeout / 106);
 }
 
+
+void iso14a_set_ATS_timeout(uint8_t *ats) {
+
+       uint8_t tb1;
+       uint8_t fwi; 
+       uint32_t fwt;
+       
+       if (ats[0] > 1) {                                                       // there is a format byte T0
+               if ((ats[1] & 0x20) == 0x20) {                  // there is an interface byte TB(1)
+                       if ((ats[1] & 0x10) == 0x10) {          // there is an interface byte TA(1) preceding TB(1)
+                               tb1 = ats[3];
+                       } else {
+                               tb1 = ats[2];
+                       }
+                       fwi = (tb1 & 0xf0) >> 4;                        // frame waiting indicator (FWI)
+                       fwt = 256 * 16 * (1 << fwi);            // frame waiting time (FWT) in 1/fc
+                       
+                       iso14a_set_timeout(fwt/(8*16));
+               }
+       }
+}
+
+
 //-----------------------------------------------------------------------------
 // Generate the parity value for a byte sequence
 //
@@ -527,12 +551,8 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
        
        LEDsoff();
 
-       // We won't start recording the frames that we acquire until we trigger;
-       // a good trigger condition to get started is probably when we see a
-       // response from the tag.
-       // triggered == FALSE -- to wait first for card
-       bool triggered = !(param & 0x03); 
-       
+       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
        // Allocate memory from BigBuf for some buffers
        // free all previous allocations first
        BigBuf_free();
@@ -559,8 +579,6 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
        bool TagIsActive = FALSE;
        bool ReaderIsActive = FALSE;
        
-       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
-
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse, receivedResponsePar);
        
@@ -570,6 +588,12 @@ void RAMFUNC SnoopIso14443a(uint8_t param) {
        // Setup and start DMA.
        FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
        
+       // We won't start recording the frames that we acquire until we trigger;
+       // a good trigger condition to get started is probably when we see a
+       // response from the tag.
+       // triggered == FALSE -- to wait first for card
+       bool triggered = !(param & 0x03); 
+       
        // And now we loop, receiving samples.
        for(uint32_t rsamples = 0; TRUE; ) {
 
@@ -1002,6 +1026,9 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
                .modulation_n = 0
        };
   
+       // We need to listen to the high-frequency, peak-detected path.
+       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
        BigBuf_free_keep_EM();
 
        // allocate buffers:
@@ -1030,16 +1057,12 @@ void SimulateIso14443aTag(int tagType, int uid_1st, int uid_2nd, byte_t* data)
        int happened2 = 0;
        int cmdsRecvd = 0;
 
-       // We need to listen to the high-frequency, peak-detected path.
-       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-
        cmdsRecvd = 0;
        tag_response_info_t* p_response;
 
        LED_A_ON();
        for(;;) {
                // Clean receive command buffer
-               
                if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) {
                        DbpString("Button press");
                        break;
@@ -1600,7 +1623,7 @@ static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receive
                        if(ManchesterDecoding(b, offset, 0)) {
                                NextTransferTime = MAX(NextTransferTime, Demod.endTime - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/16 + FRAME_DELAY_TIME_PICC_TO_PCD);
                                return TRUE;
-                       } else if (c++ > iso14a_timeout) {
+                       } else if (c++ > iso14a_timeout && Demod.state == DEMOD_UNSYNCD) {
                                return FALSE; 
                        }
                }
@@ -1798,6 +1821,10 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u
 
        // reset the PCB block number
        iso14_pcb_blocknum = 0;
+
+       // set default timeout based on ATS
+       iso14a_set_ATS_timeout(resp);
+
        return 1;       
 }
 
@@ -1862,8 +1889,9 @@ void ReaderIso14443a(UsbCommand *c)
 {
        iso14a_command_t param = c->arg[0];
        uint8_t *cmd = c->d.asBytes;
-       size_t len = c->arg[1];
-       size_t lenbits = c->arg[2];
+       size_t len = c->arg[1] & 0xffff;
+       size_t lenbits = c->arg[1] >> 16;
+       uint32_t timeout = c->arg[2];
        uint32_t arg0 = 0;
        byte_t buf[USB_CMD_DATA_SIZE];
        uint8_t par[MAX_PARITY_SIZE];
@@ -1888,7 +1916,7 @@ void ReaderIso14443a(UsbCommand *c)
        }
 
        if(param & ISO14A_SET_TIMEOUT) {
-               iso14a_set_timeout(c->arg[2]);
+               iso14a_set_timeout(timeout);
        }
 
        if(param & ISO14A_APDU) {
@@ -1942,7 +1970,7 @@ int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
                nttmp1 = prng_successor(nttmp1, 1);
                if (nttmp1 == nt2) return i;
                nttmp2 = prng_successor(nttmp2, 1);
-                       if (nttmp2 == nt1) return -i;
+               if (nttmp2 == nt1) return -i;
                }
        
        return(-99999); // either nt1 or nt2 are invalid nonces
@@ -1965,6 +1993,10 @@ void ReaderMifare(bool first_try)
        uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE];
        uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE];
 
+       if (first_try) { 
+               iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+       }
+       
        // free eventually allocated BigBuf memory. We want all for tracing.
        BigBuf_free();
        
@@ -1984,6 +2016,7 @@ void ReaderMifare(bool first_try)
        byte_t par_list[8] = {0x00};
        byte_t ks_list[8] = {0x00};
 
+       #define PRNG_SEQUENCE_LENGTH  (1 << 16);
        static uint32_t sync_time;
        static uint32_t sync_cycles;
        int catch_up_cycles = 0;
@@ -1993,9 +2026,8 @@ void ReaderMifare(bool first_try)
 
        if (first_try) { 
                mf_nr_ar3 = 0;
-               iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
                sync_time = GetCountSspClk() & 0xfffffff8;
-               sync_cycles = 65536;                                                                    // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).
+               sync_cycles = PRNG_SEQUENCE_LENGTH;                                                     // theory: Mifare Classic's random generator repeats every 2^16 cycles (and so do the tag nonces).
                nt_attacked = 0;
                nt = 0;
                par[0] = 0;
@@ -2011,33 +2043,44 @@ void ReaderMifare(bool first_try)
        LED_B_OFF();
        LED_C_OFF();
        
-  
+
+       #define MAX_UNEXPECTED_RANDOM   4               // maximum number of unexpected (i.e. real) random numbers when trying to sync. Then give up.
+       #define MAX_SYNC_TRIES                  16
+       uint16_t unexpected_random = 0;
+       uint16_t sync_tries = 0;
+       int16_t debug_info_nr = -1;
+       uint32_t debug_info[MAX_SYNC_TRIES];
+       
        for(uint16_t i = 0; TRUE; i++) {
                
+               LED_C_ON();
                WDT_HIT();
 
                // Test if the action was cancelled
                if(BUTTON_PRESS()) {
+                       isOK = -1;
                        break;
                }
                
-               LED_C_ON();
-
                if(!iso14443a_select_card(uid, NULL, &cuid)) {
                        if (MF_DBGLEVEL >= 1)   Dbprintf("Mifare: Can't select card");
                        continue;
                }
 
-               sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
-               catch_up_cycles = 0;
+               if (debug_info_nr == -1) {
+                       sync_time = (sync_time & 0xfffffff8) + sync_cycles + catch_up_cycles;
+                       catch_up_cycles = 0;
 
-               // if we missed the sync time already, advance to the next nonce repeat
-               while(GetCountSspClk() > sync_time) {
-                       sync_time = (sync_time & 0xfffffff8) + sync_cycles;
-               }
+                       // if we missed the sync time already, advance to the next nonce repeat
+                       while(GetCountSspClk() > sync_time) {
+                               sync_time = (sync_time & 0xfffffff8) + sync_cycles;
+                       }
 
-               // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) 
-               ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+                       // Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked) 
+                       ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+               } else {
+                       ReaderTransmit(mf_auth, sizeof(mf_auth), NULL);
+               }                       
 
                // Receive the (4 Byte) "random" nonce
                if (!ReaderReceive(receivedAnswer, receivedAnswerPar)) {
@@ -2055,13 +2098,32 @@ void ReaderMifare(bool first_try)
                        int nt_distance = dist_nt(previous_nt, nt);
                        if (nt_distance == 0) {
                                nt_attacked = nt;
-                       }
-                       else {
-                               if (nt_distance == -99999) { // invalid nonce received, try again
-                                       continue;
+                       } else {
+                               if (nt_distance == -99999) { // invalid nonce received
+                                       unexpected_random++;
+                                       if (!nt_attacked && unexpected_random > MAX_UNEXPECTED_RANDOM) {
+                                               isOK = -3;              // Card has an unpredictable PRNG. Give up      
+                                               break;
+                                       } else {
+                                               continue;               // continue trying...
+                                       }
+                               }
+                               if (++sync_tries > MAX_SYNC_TRIES) {
+                                       if (sync_tries > 2 * MAX_SYNC_TRIES) {
+                                               isOK = -4;                      // Card's PRNG runs at an unexpected frequency or resets unexpectedly
+                                               break;
+                                       } else {                                // continue for a while, just to collect some debug info
+                                               debug_info[++debug_info_nr] = nt_distance;
+                                               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);
+                               if (sync_cycles <= 0) {
+                                       sync_cycles += PRNG_SEQUENCE_LENGTH;
+                               }
+                               if (MF_DBGLEVEL >= 3) {
+                                       Dbprintf("calibrating in cycle %d. nt_distance=%d, Sync_cycles: %d\n", i, nt_distance, sync_cycles);
+                               }
                                continue;
                        }
                }
@@ -2120,6 +2182,10 @@ void ReaderMifare(bool first_try)
                        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;
                        }
@@ -2128,6 +2194,14 @@ void ReaderMifare(bool first_try)
 
 
        mf_nr_ar[3] &= 0x1F;
+
+       if (isOK == -4) {
+               if (MF_DBGLEVEL >= 3) {
+                       for(uint16_t i = 0; i < MAX_SYNC_TRIES; i++) {
+                               Dbprintf("collected debug info[%d] = %d\n", i, debug_info[i]);
+                       }
+               }
+       }
        
        byte_t buf[28];
        memcpy(buf + 0,  uid, 4);
@@ -2136,7 +2210,7 @@ void ReaderMifare(bool first_try)
        memcpy(buf + 16, ks_list, 8);
        memcpy(buf + 24, mf_nr_ar, 4);
                
-       cmd_send(CMD_ACK,isOK,0,0,buf,28);
+       cmd_send(CMD_ACK, isOK, 0, 0, buf, 28);
 
        // Thats it...
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
@@ -2197,13 +2271,6 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
        uint32_t ar_nr_responses[] = {0,0,0,0,0,0,0,0};
        uint8_t ar_nr_collected = 0;
 
-       // free eventually allocated BigBuf memory but keep Emulator Memory
-       BigBuf_free_keep_EM();
-
-       // clear trace
-       clear_trace();
-       set_tracing(TRUE);
-
        // Authenticate response - nonce
        uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
        
@@ -2241,13 +2308,10 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
        if (_7BUID) {
                rATQA[0] = 0x44;
                rUIDBCC1[0] = 0x88;
+               rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
                rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
        }
 
-       // We need to listen to the high-frequency, peak-detected path.
-       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-
-
        if (MF_DBGLEVEL >= 1)   {
                if (!_7BUID) {
                        Dbprintf("4B UID: %02x%02x%02x%02x", 
@@ -2259,6 +2323,17 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
                }
        }
 
+       // We need to listen to the high-frequency, peak-detected path.
+       iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
+
+       // free eventually allocated BigBuf memory but keep Emulator Memory
+       BigBuf_free_keep_EM();
+
+       // clear trace
+       clear_trace();
+       set_tracing(TRUE);
+
+
        bool finished = FALSE;
        while (!BUTTON_PRESS() && !finished) {
                WDT_HIT();
@@ -2480,13 +2555,13 @@ void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *
                                                || receivedCmd[0] == 0xB0) { // transfer
                                        if (receivedCmd[1] >= 16 * 4) {
                                                EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]);
+                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]);
                                                break;
                                        }
 
                                        if (receivedCmd[1] / 4 != cardAUTHSC) {
                                                EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
-                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC);
+                                               if (MF_DBGLEVEL >= 2) Dbprintf("Reader tried to operate (0x%02x) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC);
                                                break;
                                        }
                                }
@@ -2677,10 +2752,8 @@ void RAMFUNC SniffMifare(uint8_t param) {
        uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE];
        uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE];
 
-       // As we receive stuff, we copy it from receivedCmd or receivedResponse
-       // into trace, along with its length and other annotations.
-       //uint8_t *trace = (uint8_t *)BigBuf;
-       
+       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
        // free eventually allocated BigBuf memory
        BigBuf_free();
        // allocate the DMA buffer, used to stream samples from the FPGA
@@ -2692,8 +2765,6 @@ void RAMFUNC SniffMifare(uint8_t param) {
        bool ReaderIsActive = FALSE;
        bool TagIsActive = FALSE;
 
-       iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
-
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse, receivedResponsePar);
 
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