implement 'hf iclass snoop -j'

[proxmark3-svn] / armsrc / iso15693.c

diff --git a/armsrc/iso15693.c b/armsrc/iso15693.c
index 9c50c0362f14cdebb22832871a056e8e3f6d6fe0..f10b0206b4a454405f93c82b0ac9a3f8dbab7299 100644 (file)
--- a/armsrc/iso15693.c
+++ b/armsrc/iso15693.c
@@ -84,7 +84,7 @@ static int DEBUG = 0;
 ///////////////////////////////////////////////////////////////////////
 
 // buffers
-#define ISO15693_DMA_BUFFER_SIZE        128 // must be a power of 2
+#define ISO15693_DMA_BUFFER_SIZE        256 // must be a power of 2
 #define ISO15693_MAX_RESPONSE_LENGTH     36 // allows read single block with the maximum block size of 256bits. Read multiple blocks not supported yet
 #define ISO15693_MAX_COMMAND_LENGTH      45 // allows write single block with the maximum block size of 256bits. Write multiple blocks not supported yet
 
@@ -341,11 +341,6 @@ void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t *start_time,
 }
 
 
-static void jam(void) {
-       // send a short burst to jam the reader signal
-}
-
-
 //=============================================================================
 // An ISO 15693 decoder for tag responses (one subcarrier only).
 // Uses cross correlation to identify each bit and EOF.
@@ -392,7 +387,7 @@ typedef struct DecodeTag {
 } DecodeTag_t;
 
 
-static int inline __attribute__((always_inline)) Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *restrict DecodeTag) {
+static int inline __attribute__((always_inline)) Handle15693SamplesFromTag(uint16_t amplitude, DecodeTag_t *DecodeTag) {
        switch (DecodeTag->state) {
                case STATE_TAG_SOF_LOW:
                        // waiting for a rising edge
@@ -745,7 +740,8 @@ typedef struct DecodeReader {
                STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF,
                STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4,
                STATE_READER_RECEIVE_DATA_1_OUT_OF_4,
-               STATE_READER_RECEIVE_DATA_1_OUT_OF_256
+               STATE_READER_RECEIVE_DATA_1_OUT_OF_256,
+               STATE_READER_RECEIVE_JAMMING
        }           state;
        enum {
                CODING_1_OUT_OF_4,
@@ -781,7 +777,7 @@ static void DecodeReaderReset(DecodeReader_t* DecodeReader) {
 }
 
 
-static int inline __attribute__((always_inline)) Handle15693SampleFromReader(bool bit, DecodeReader_t *restrict DecodeReader) {
+static int inline __attribute__((always_inline)) Handle15693SampleFromReader(bool bit, DecodeReader_t *DecodeReader) {
        switch (DecodeReader->state) {
                case STATE_READER_UNSYNCD:
                        // wait for unmodulated carrier
@@ -920,12 +916,6 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(boo
                                }
                                if (DecodeReader->bitCount == 15) { // we have a full byte
                                        DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg;
-                                       if (DecodeReader->byteCount == DecodeReader->jam_search_len) {
-                                               if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) {
-                                                       jam(); // send a jamming signal
-                                                       Dbprintf("JAMMING!");
-                                               }
-                                       }
                                        if (DecodeReader->byteCount > DecodeReader->byteCountMax) {
                                                // buffer overflow, give up
                                                LED_B_OFF();
@@ -933,6 +923,13 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(boo
                                        }
                                        DecodeReader->bitCount = 0;
                                        DecodeReader->shiftReg = 0;
+                                       if (DecodeReader->byteCount == DecodeReader->jam_search_len) {
+                                               if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) {
+                                                       LED_D_ON();
+                                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_JAM);
+                                                       DecodeReader->state = STATE_READER_RECEIVE_JAMMING;
+                                               }
+                                       }
                                } else {
                                        DecodeReader->bitCount++;
                                }
@@ -968,11 +965,42 @@ static int inline __attribute__((always_inline)) Handle15693SampleFromReader(boo
                                                LED_B_OFF();
                                                DecodeReaderReset(DecodeReader);
                                        }
+                                       if (DecodeReader->byteCount == DecodeReader->jam_search_len) {
+                                               if (!memcmp(DecodeReader->output, DecodeReader->jam_search_string, DecodeReader->jam_search_len)) {
+                                                       LED_D_ON();
+                                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SEND_JAM);
+                                                       DecodeReader->state = STATE_READER_RECEIVE_JAMMING;
+                                               }
+                                       }
                                }
                                DecodeReader->bitCount++;
                        }
                        break;
 
+               case STATE_READER_RECEIVE_JAMMING:
+                       DecodeReader->posCount++;
+                       if (DecodeReader->Coding == CODING_1_OUT_OF_4) {
+                               if (DecodeReader->posCount == 7*16) { // 7 bits jammed
+                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); // stop jamming
+                                       // FpgaDisableTracing();
+                                       LED_D_OFF();
+                               } else if (DecodeReader->posCount == 8*16) {
+                                       DecodeReader->posCount = 0;
+                                       DecodeReader->output[DecodeReader->byteCount++] = 0x00;
+                                       DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_4;
+                               }
+                       } else {
+                               if (DecodeReader->posCount == 7*256) { // 7 bits jammend
+                                       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER | FPGA_HF_READER_MODE_SNOOP_AMPLITUDE); // stop jamming
+                                       LED_D_OFF();
+                               } else if (DecodeReader->posCount == 8*256) {
+                                       DecodeReader->posCount = 0;
+                                       DecodeReader->output[DecodeReader->byteCount++] = 0x00;
+                                       DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_256;
+                               }
+                       }
+                       break;
+
                default:
                        LED_B_OFF();
                        DecodeReaderReset(DecodeReader);
@@ -1212,7 +1240,7 @@ void SnoopIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
                if (upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) {                   // we have read all of the DMA buffer content.
                        upTo = dmaBuf;                                                 // start reading the circular buffer from the beginning
                        if (behindBy > (9*ISO15693_DMA_BUFFER_SIZE/10)) {
-                               FpgaDisableTracing();
+                               // FpgaDisableTracing();
                                Dbprintf("About to blow circular buffer - aborted! behindBy=%d, samples=%d", behindBy, samples);
                                break;
                        }
@@ -1305,8 +1333,6 @@ void SnoopIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
 
        FpgaDisableSscDma();
 
-       LEDsoff();
-
        DbpString("Snoop statistics:");
        Dbprintf("  ExpectTagAnswer: %d, TagIsActive: %d, ReaderIsActive: %d", ExpectTagAnswer, TagIsActive, ReaderIsActive);
        Dbprintf("  DecodeTag State: %d", DecodeTag.state);