InstaFob

rfid/instafob/protocol_insta_fob.c

@@ -0,0 +1,374 @@
+#include <furi.h>
+#include <toolbox/protocols/protocol.h>
+
+#include <bit_lib/bit_lib.h>
+
+#include <toolbox/manchester_decoder.h>
+
+// #include <lfrfid/tools/fsk_demod.h>
+// #include <lfrfid/tools/fsk_osc.h>
+
+#include "lfrfid_protocols.h"
+
+#define TAG "InstaFob"
+
+#define INSTAFOB_DECODED_DATA_SIZE_BYTES (8)
+
+#define INSTAFOB_ENCODED_DATA_SIZE_BYTES ((4 * 7) + 1)
+#define INSTAFOB_ENCODED_DATA_SIZE_BITS ((8 * 4 * 7) + 1)
+#define INSTAFOB_ENCODED_DATA_OFFSET (7)
+
+#define INSTAFOB_BLOCK1 (0x00107060)
+
+#define LFRFID_FREQUENCY (125000)
+#define INSTAFOB_CLOCK_PER_BIT (32)
+#define INSTAFOB_READ_LONG_TIME_BASE (1000000 / (LFRFID_FREQUENCY / INSTAFOB_CLOCK_PER_BIT))
+#define INSTAFOB_READ_SHORT_TIME_BASE (INSTAFOB_READ_LONG_TIME_BASE / 2)
+#define INSTAFOB_READ_SEQTERM_TIME_BASE \
+    (1000000 / (LFRFID_FREQUENCY * 32 / 50 / INSTAFOB_CLOCK_PER_BIT))
+#define INSTAFOB_READ_JITTER_TIME_BASE (INSTAFOB_READ_SHORT_TIME_BASE * 40 / 100)
+// #define INSTAFOB_CHECK_AS_WE_GO 1
+
+typedef enum {
+    ProtocolInstaFobSeqTermNone = 0,
+    ProtocolInstaFobSeqTermS1,
+    ProtocolInstaFobSeqTermS2,
+    ProtocolInstaFobSeqTermS3,
+    ProtocolInstaFobSeqTermS4,
+    ProtocolInstaFobSeqTermS5,
+    ProtocolInstaFobSeqTermS6,
+    ProtocolInstaFobSeqTermSMax,
+} ProtocolInstaFobSeqTermState;
+
+typedef struct {
+    uint8_t data[INSTAFOB_DECODED_DATA_SIZE_BYTES];
+
+    uint8_t encoded_data[INSTAFOB_ENCODED_DATA_SIZE_BYTES];
+    uint8_t encoded_data_index;
+    bool encoded_polarity;
+    ProtocolInstaFobSeqTermState encoded_term_state;
+    FuriString* debug_string;
+
+    ManchesterState decoder_manchester_state;
+} ProtocolInstaFob;
+
+ProtocolInstaFob* protocol_insta_fob_alloc(void) {
+    ProtocolInstaFob* protocol = malloc(sizeof(ProtocolInstaFob));
+    bit_lib_num_to_bytes_be(INSTAFOB_BLOCK1, 4, protocol->data);
+    protocol->debug_string = furi_string_alloc();
+    return (void*)protocol;
+};
+
+void protocol_insta_fob_free(ProtocolInstaFob* protocol) {
+    free(protocol->debug_string);
+    free(protocol);
+};
+
+uint8_t* protocol_insta_fob_get_data(ProtocolInstaFob* protocol) {
+    return protocol->data;
+};
+
+void protocol_insta_fob_decoder_start(ProtocolInstaFob* protocol) {
+    memset(protocol->data, 0, INSTAFOB_DECODED_DATA_SIZE_BYTES);
+    memset(protocol->encoded_data, 0, INSTAFOB_ENCODED_DATA_SIZE_BYTES);
+    manchester_advance(
+        protocol->decoder_manchester_state,
+        ManchesterEventReset,
+        &protocol->decoder_manchester_state,
+        NULL);
+    protocol->encoded_polarity = false;
+    protocol->encoded_term_state = ProtocolInstaFobSeqTermNone;
+};
+
+static const char* protocol_insta_fob_get_encoded_data(ProtocolInstaFob* protocol) {
+    furi_string_reset(protocol->debug_string);
+    for(size_t i = 0; i < INSTAFOB_ENCODED_DATA_SIZE_BITS; i++) {
+        furi_string_cat(
+            protocol->debug_string, bit_lib_get_bit(protocol->encoded_data, i) ? "1" : "0");
+    }
+    return furi_string_get_cstr(protocol->debug_string);
+};
+
+static bool protocol_insta_fob_can_be_decoded(ProtocolInstaFob* protocol) {
+    return bit_lib_get_bits_32(protocol->encoded_data, INSTAFOB_ENCODED_DATA_OFFSET, 32) ==
+           INSTAFOB_BLOCK1;
+}
+
+static void protocol_insta_fob_decode(ProtocolInstaFob* protocol) {
+    bit_lib_copy_bits(protocol->data, 0, 64, protocol->encoded_data, INSTAFOB_ENCODED_DATA_OFFSET);
+};
+
+static bool protocol_insta_fob_in_range(uint32_t value, uint32_t base, uint32_t jitter) {
+    return (value > (base - jitter)) && (value < (base + jitter));
+};
+
+static ManchesterEvent protocol_insta_fob_manchester_event(bool level, uint32_t duration_us) {
+    ManchesterEvent event = ManchesterEventReset;
+
+    if(protocol_insta_fob_in_range(
+           duration_us, INSTAFOB_READ_SHORT_TIME_BASE, INSTAFOB_READ_JITTER_TIME_BASE)) {
+        if(!level) {
+            event = ManchesterEventShortHigh;
+        } else {
+            event = ManchesterEventShortLow;
+        }
+    } else if(protocol_insta_fob_in_range(
+                  duration_us, INSTAFOB_READ_LONG_TIME_BASE, INSTAFOB_READ_JITTER_TIME_BASE)) {
+        if(!level) {
+            event = ManchesterEventLongHigh;
+        } else {
+            event = ManchesterEventLongLow;
+        }
+    }
+
+    return event;
+};
+
+static bool protocol_insta_fob_is_sequence_terminator(uint32_t duration_us) {
+    return protocol_insta_fob_in_range(
+        duration_us, INSTAFOB_READ_SEQTERM_TIME_BASE, INSTAFOB_READ_JITTER_TIME_BASE);
+};
+
+static bool protocol_insta_fob_decoder_seq_terminator(
+    ProtocolInstaFob* protocol,
+    bool level,
+    uint32_t duration_us) {
+    bool decoded_signal = false;
+    ManchesterEvent event = protocol_insta_fob_manchester_event(level, duration_us);
+
+    if(level && protocol_insta_fob_is_sequence_terminator(duration_us)) {
+        protocol->encoded_term_state = ProtocolInstaFobSeqTermS3;
+    } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS3) {
+        if(event == ManchesterEventShortHigh) {
+            // We found expected next part of sequence terminator.
+            protocol->encoded_term_state = ProtocolInstaFobSeqTermS4;
+        } else {
+            // Unexpected signal, start scanning the card again.
+            protocol->encoded_term_state = ProtocolInstaFobSeqTermNone;
+        }
+    } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS4) {
+        if(event == ManchesterEventLongLow) {
+            protocol->encoded_term_state = ProtocolInstaFobSeqTermS6;
+        } else {
+            // Unexpected signal, start scanning the card again.
+            protocol->encoded_term_state = ProtocolInstaFobSeqTermNone;
+        }
+    } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS6) {
+        // We found the last part of sequence terminator!
+
+        // Check if our data is valid.
+        if(protocol_insta_fob_can_be_decoded(protocol)) {
+            protocol_insta_fob_decode(protocol);
+            decoded_signal = true;
+
+            FURI_LOG_D(TAG, "Decoded %s", protocol_insta_fob_get_encoded_data(protocol));
+
+            // Clear the encoded data, reset to the first bit.
+            memset(protocol->encoded_data, 0, INSTAFOB_ENCODED_DATA_SIZE_BYTES);
+            protocol->encoded_polarity = false;
+        } else {
+            FURI_LOG_D(TAG, "Failed decoding %s", protocol_insta_fob_get_encoded_data(protocol));
+        }
+
+        protocol->encoded_term_state = ProtocolInstaFobSeqTermNone;
+    } else {
+        // Unknown signal, ignore.
+    }
+
+    return decoded_signal;
+}
+
+bool protocol_insta_fob_decoder_feed(ProtocolInstaFob* protocol, bool level, uint32_t duration_us) {
+    bool decoded_signal = false;
+    ManchesterEvent event = protocol_insta_fob_manchester_event(level, duration_us);
+
+    if(protocol->encoded_term_state || event == ManchesterEventReset) {
+        return protocol_insta_fob_decoder_seq_terminator(protocol, level, duration_us);
+    }
+
+    bool data;
+    bool data_ok = manchester_advance(
+        protocol->decoder_manchester_state, event, &protocol->decoder_manchester_state, &data);
+    // If data_ok is false, it means we only decoded the first half of the bit.
+    // When data_ok is true, we decoded both halves of the bit and "data" variable is set.
+
+    if(data_ok) {
+        // Mark that we read the second half of signal
+        protocol->encoded_polarity = false;
+
+        bit_lib_push_bit(protocol->encoded_data, INSTAFOB_ENCODED_DATA_SIZE_BYTES, data);
+
+#ifdef INSTAFOB_CHECK_AS_WE_GO
+        if(protocol_insta_fob_can_be_decoded(protocol)) {
+            protocol_insta_fob_decode(protocol);
+            decoded_signal = true;
+
+            memset(protocol->encoded_data, 0, INSTAFOB_ENCODED_DATA_SIZE_BYTES);
+            protocol->encoded_polarity = false;
+        }
+#endif
+    } else {
+        // encoded_polarity should be false when we are at the first half of the signal.
+        // If it is true, then we are actually at the beginning of the first set bit.
+
+        if(protocol->encoded_polarity) {
+            memset(protocol->encoded_data, 0, INSTAFOB_ENCODED_DATA_SIZE_BYTES);
+            bit_lib_push_bit(protocol->encoded_data, INSTAFOB_ENCODED_DATA_SIZE_BYTES, 1);
+        }
+
+        // Mark that we read the first half of signal
+        protocol->encoded_polarity = true;
+    }
+
+    return decoded_signal;
+};
+
+bool protocol_insta_fob_encoder_start(ProtocolInstaFob* protocol) {
+    uint32_t block1 = bit_lib_get_bits_32(protocol->data, 0, 32);
+    if(block1 != INSTAFOB_BLOCK1) {
+        FURI_LOG_E(
+            TAG,
+            "Block 1 has wrong data (%08lx). Updating to %08lx.",
+            block1,
+            (uint32_t)INSTAFOB_BLOCK1);
+
+        bit_lib_num_to_bytes_be(INSTAFOB_BLOCK1, 4, protocol->data);
+    }
+
+    // You can add parity or other data manipulation here.
+
+    // Set all of our encoded_data bits to zeros.
+    memset(protocol->encoded_data, 0, INSTAFOB_ENCODED_DATA_SIZE_BYTES);
+
+    // Copy the data to the beginning of our data onto the encoded_data
+    bit_lib_copy_bits(
+        protocol->encoded_data, 0, 8 * INSTAFOB_DECODED_DATA_SIZE_BYTES, protocol->data, 0);
+
+    // Note: For sending we start at bit 0.
+    protocol->encoded_data_index = 0;
+    protocol->encoded_polarity = true;
+    protocol->encoded_term_state = ProtocolInstaFobSeqTermNone;
+
+    return true;
+}
+
+LevelDuration protocol_insta_fob_encoder_yield(ProtocolInstaFob* protocol) {
+    bool level = bit_lib_get_bit(protocol->encoded_data, protocol->encoded_data_index);
+    uint32_t duration_cycles = INSTAFOB_CLOCK_PER_BIT / 2;
+
+    if(protocol->encoded_term_state == ProtocolInstaFobSeqTermNone) {
+        if(protocol->encoded_polarity) {
+            protocol->encoded_polarity = false;
+        } else {
+            level = !level;
+
+            protocol->encoded_polarity = true;
+            protocol->encoded_data_index++;
+            if(protocol->encoded_data_index == (INSTAFOB_ENCODED_DATA_SIZE_BITS - 1)) {
+                // Next yield call will be the start of the sequence terminator.
+                protocol->encoded_term_state = ProtocolInstaFobSeqTermS1;
+            }
+        }
+    } else {
+        // States 1-2 will send a "1" bit.  This is what I observed on the ProxMark3.
+        // States 3-4 will send a "." bit due to invalid duration (Really long high then short low).
+        // States 5-6 will send a "." bit due to invalid duration (A long high).
+        if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS1) {
+            level = true;
+        } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS2) {
+            level = !true;
+        } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS3) {
+            level = true;
+            duration_cycles = INSTAFOB_CLOCK_PER_BIT * 50 / 32;
+        } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS4) {
+            level = false;
+        } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS5) {
+            level = true;
+        } else if(protocol->encoded_term_state == ProtocolInstaFobSeqTermS6) {
+            level = true;
+        }
+
+        // Move to the next state.
+        protocol->encoded_term_state++;
+
+        if(protocol->encoded_term_state == ProtocolInstaFobSeqTermSMax) {
+            // We are sending the end of the sequence terminator.
+            // Set variables so next yield call will send the first half of the first bit.
+            protocol->encoded_term_state = ProtocolInstaFobSeqTermNone;
+            protocol->encoded_data_index = 0;
+            protocol->encoded_polarity = true;
+        }
+    }
+
+    return level_duration_make(level, duration_cycles);
+};
+
+void protocol_insta_fob_render_data(ProtocolInstaFob* protocol, FuriString* result) {
+    furi_string_printf(
+        result,
+        "InstaFob\nBlk[1]: %08lX\nBlk[2]: %08lX",
+        bit_lib_get_bits_32(protocol->data, 0, 32),
+        bit_lib_get_bits_32(protocol->data, 32, 32));
+};
+
+void protocol_insta_fob_render_brief_data(ProtocolInstaFob* protocol, FuriString* result) {
+    furi_string_printf(
+        result,
+        "Fob %08lX %08lX",
+        bit_lib_get_bits_32(protocol->data, 0, 32),
+        bit_lib_get_bits_32(protocol->data, 32, 32));
+};
+
+bool protocol_insta_fob_write_data(ProtocolInstaFob* protocol, void* data) {
+    LFRFIDWriteRequest* request = (LFRFIDWriteRequest*)data;
+    bool result = false;
+
+    // Encode data
+    protocol_insta_fob_encoder_start(protocol);
+
+    if(request->write_type == LFRFIDWriteTypeT5577) {
+        request->t5577.block[0] =
+            (LFRFID_T5577_MODULATION_MANCHESTER | LFRFID_T5577_BITRATE_RF_32 |
+             LFRFID_T5577_ST_TERMINATOR | (7 << LFRFID_T5577_MAXBLOCK_SHIFT));
+        request->t5577.block[1] = bit_lib_get_bits_32(protocol->encoded_data, 0, 32);
+        request->t5577.block[2] = bit_lib_get_bits_32(protocol->encoded_data, 32, 32);
+        // Clear the rest of the blocks
+        for(int i = 3; i < 8; i++) {
+            request->t5577.block[i] = 0;
+        }
+        request->t5577.blocks_to_write = 8;
+        result = true;
+
+        FURI_LOG_D(
+            TAG,
+            "block[0]: %08lx block[1]: %08lx block[2]: %08lx",
+            request->t5577.block[0],
+            request->t5577.block[1],
+            request->t5577.block[2]);
+    }
+    return result;
+};
+
+const ProtocolBase protocol_insta_fob = {
+    .name = "InstaFob",
+    .manufacturer = "Hillman Group",
+    .data_size = INSTAFOB_DECODED_DATA_SIZE_BYTES,
+    .features = LFRFIDFeatureASK,
+    .validate_count = 3,
+    .alloc = (ProtocolAlloc)protocol_insta_fob_alloc,
+    .free = (ProtocolFree)protocol_insta_fob_free,
+    .get_data = (ProtocolGetData)protocol_insta_fob_get_data,
+    .decoder =
+        {
+            .start = (ProtocolDecoderStart)protocol_insta_fob_decoder_start,
+            .feed = (ProtocolDecoderFeed)protocol_insta_fob_decoder_feed,
+        },
+    .encoder =
+        {
+            .start = (ProtocolEncoderStart)protocol_insta_fob_encoder_start,
+            .yield = (ProtocolEncoderYield)protocol_insta_fob_encoder_yield,
+        },
+    .render_data = (ProtocolRenderData)protocol_insta_fob_render_data,
+    .render_brief_data = (ProtocolRenderData)protocol_insta_fob_render_brief_data,
+    .write_data = (ProtocolWriteData)protocol_insta_fob_write_data,
+};

rfid/instafob/protocol_insta_fob.h

@@ -0,0 +1,4 @@
+#pragma once
+#include <toolbox/protocols/protocol.h>
+
+extern const ProtocolBase protocol_insta_fob;