meant to put clock detection before demods

[proxmark3-svn] / armsrc / iso14443b.c

diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c
index bfbd7bf59ce1aa18defc1037127aaf2a0a16c679..22227e74bec96651d5c2620dd37f4bea210f27d2 100644 (file)
--- a/armsrc/iso14443b.c
+++ b/armsrc/iso14443b.c
@@ -19,6 +19,9 @@
 #define RECEIVE_SAMPLES_TIMEOUT 2000
 #define ISO14443B_DMA_BUFFER_SIZE 256
 
+// PCB Block number for APDUs
+static uint8_t pcb_blocknum = 0;
+
 //=============================================================================
 // An ISO 14443 Type B tag. We listen for commands from the reader, using
 // a UART kind of thing that's implemented in software. When we get a
@@ -311,7 +314,7 @@ static int GetIso14443bCommandFromReader(uint8_t *received, uint16_t *len)
                        }
                }
        }
-       
+
        return FALSE;
 }
 
@@ -544,15 +547,20 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
        }
  */
 // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq)))
+
+       //note: couldn't we just use MAX(ABS(ci),ABS(cq)) + (MIN(ABS(ci),ABS(cq))/2) from common.h - marshmellow
 #define CHECK_FOR_SUBCARRIER() { \
+               v = MAX(ABS(ci),ABS(cq)) + (MIN(ABS(ci),ABS(cq))/2); \
+       }
+               /*
                if(ci < 0) { \
-                       if(cq < 0) { /* ci < 0, cq < 0 */ \
+                       if(cq < 0) { \ // ci < 0, cq < 0
                                if (cq < ci) { \
                                        v = -cq - (ci >> 1); \
                                } else { \
                                        v = -ci - (cq >> 1); \
                                } \
-                       } else {        /* ci < 0, cq >= 0 */ \
+                       } else {        \ // ci < 0, cq >= 0
                                if (cq < -ci) { \
                                        v = -ci + (cq >> 1); \
                                } else { \
@@ -560,13 +568,13 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
                                } \
                        } \
                } else { \
-                       if(cq < 0) { /* ci >= 0, cq < 0 */ \
+                       if(cq < 0) { \ // ci >= 0, cq < 0
                                if (-cq < ci) { \
                                        v = ci - (cq >> 1); \
                                } else { \
                                        v = -cq + (ci >> 1); \
                                } \
-                       } else {        /* ci >= 0, cq >= 0 */ \
+                       } else {        \ // ci >= 0, cq >= 0
                                if (cq < ci) { \
                                        v = ci + (cq >> 1); \
                                } else { \
@@ -575,6 +583,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
                        } \
                } \
        }
+               */
 
        switch(Demod.state) {
                case DEMOD_UNSYNCD:
@@ -924,6 +933,98 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len)
        }
 }
 
+/* Sends an APDU to the tag
+ * TODO: check CRC and preamble
+ */
+int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *response)
+{
+       uint8_t message_frame[message_length + 4];
+       // PCB
+       message_frame[0] = 0x0A | pcb_blocknum;
+       pcb_blocknum ^= 1;
+       // CID
+       message_frame[1] = 0;
+       // INF
+       memcpy(message_frame + 2, message, message_length);
+       // EDC (CRC)
+       ComputeCrc14443(CRC_14443_B, message_frame, message_length + 2, &message_frame[message_length + 2], &message_frame[message_length + 3]);
+       // send
+       CodeAndTransmit14443bAsReader(message_frame, message_length + 4);
+       // get response
+       GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT*100, TRUE);
+       if(Demod.len < 3)
+       {
+               return 0;
+       }
+       // TODO: Check CRC
+       // copy response contents
+       if(response != NULL)
+       {
+               memcpy(response, Demod.output, Demod.len);
+       }
+       return Demod.len;
+}
+
+/* Perform the ISO 14443 B Card Selection procedure
+ * Currently does NOT do any collision handling.
+ * It expects 0-1 cards in the device's range.
+ * TODO: Support multiple cards (perform anticollision)
+ * TODO: Verify CRC checksums
+ */
+int iso14443b_select_card()
+{
+       // WUPB command (including CRC)
+       // Note: WUPB wakes up all tags, REQB doesn't wake up tags in HALT state
+       static const uint8_t wupb[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
+       // ATTRIB command (with space for CRC)
+       uint8_t attrib[] = { 0x1D, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00};
+
+       // first, wake up the tag
+       CodeAndTransmit14443bAsReader(wupb, sizeof(wupb));
+       GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+       // ATQB too short?
+       if (Demod.len < 14)
+       {
+               return 2;
+       }
+
+    // select the tag
+    // copy the PUPI to ATTRIB
+    memcpy(attrib + 1, Demod.output + 1, 4);
+    /* copy the protocol info from ATQB (Protocol Info -> Protocol_Type) into
+    ATTRIB (Param 3) */
+    attrib[7] = Demod.output[10] & 0x0F;
+    ComputeCrc14443(CRC_14443_B, attrib, 9, attrib + 9, attrib + 10);
+    CodeAndTransmit14443bAsReader(attrib, sizeof(attrib));
+    GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+    // Answer to ATTRIB too short?
+    if(Demod.len < 3)
+       {
+               return 2;
+       }
+       // reset PCB block number
+       pcb_blocknum = 0;
+       return 1;
+}
+
+// Set up ISO 14443 Type B communication (similar to iso14443a_setup)
+void iso14443b_setup() {
+       FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+       // Set up the synchronous serial port
+       FpgaSetupSsc();
+       // connect Demodulated Signal to ADC:
+       SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+       // Signal field is on with the appropriate LED
+    LED_D_ON();
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
+
+       // Start the timer
+       StartCountSspClk();
+
+       DemodReset();
+       UartReset();
+}
 
 //-----------------------------------------------------------------------------
 // Read a SRI512 ISO 14443B tag.