flipper-zero-tutorials/rfid/instafob/protocol_insta_fob.c
Derek Jamison e6acfb405f InstaFob
2024-05-10 19:45:00 -05:00

375 lines
14 KiB
C

#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,
};