flipperzero-firmware/lib/lfrfid/protocols/protocol_pac_stanley.c
Sebastian Mauer 1350dcaf63
Add support for PAC/Stanley tags (#1648)
* Add support for PAC/Stanley tags
* Address review comments
2022-08-30 01:04:17 +10:00

227 lines
8.3 KiB
C

#include <furi.h>
#include <math.h>
#include <toolbox/protocols/protocol.h>
#include <toolbox/hex.h>
#include <lfrfid/tools/bit_lib.h>
#include "lfrfid_protocols.h"
#define PAC_STANLEY_ENCODED_BIT_SIZE (128)
#define PAC_STANLEY_ENCODED_BYTE_SIZE (((PAC_STANLEY_ENCODED_BIT_SIZE) / 8))
#define PAC_STANLEY_PREAMBLE_BIT_SIZE (8)
#define PAC_STANLEY_PREAMBLE_BYTE_SIZE (1)
#define PAC_STANLEY_ENCODED_BYTE_FULL_SIZE \
(PAC_STANLEY_ENCODED_BYTE_SIZE + PAC_STANLEY_PREAMBLE_BYTE_SIZE)
#define PAC_STANLEY_BYTE_LENGTH (10) // start bit, 7 data bits, parity bit, stop bit
#define PAC_STANLEY_DATA_START_INDEX 8 + (3 * PAC_STANLEY_BYTE_LENGTH) + 1
#define PAC_STANLEY_DECODED_DATA_SIZE (4)
#define PAC_STANLEY_ENCODED_DATA_SIZE (sizeof(ProtocolPACStanley))
#define PAC_STANLEY_CLOCKS_IN_US (32)
#define PAC_STANLEY_CYCLE_LENGTH (256)
#define PAC_STANLEY_MIN_TIME (60)
#define PAC_STANLEY_MAX_TIME (4000)
typedef struct {
bool inverted;
bool got_preamble;
size_t encoded_index;
uint8_t encoded_data[PAC_STANLEY_ENCODED_BYTE_FULL_SIZE];
uint8_t data[PAC_STANLEY_DECODED_DATA_SIZE];
} ProtocolPACStanley;
ProtocolPACStanley* protocol_pac_stanley_alloc(void) {
ProtocolPACStanley* protocol = malloc(sizeof(ProtocolPACStanley));
return (void*)protocol;
}
void protocol_pac_stanley_free(ProtocolPACStanley* protocol) {
free(protocol);
}
uint8_t* protocol_pac_stanley_get_data(ProtocolPACStanley* protocol) {
return protocol->data;
}
static void protocol_pac_stanley_decode(ProtocolPACStanley* protocol) {
uint8_t asciiCardId[8];
for(size_t idx = 0; idx < 8; idx++) {
uint8_t byte = bit_lib_reverse_8_fast(bit_lib_get_bits(
protocol->encoded_data,
PAC_STANLEY_DATA_START_INDEX + (PAC_STANLEY_BYTE_LENGTH * idx),
8));
asciiCardId[idx] = byte & 0x7F; // discard the parity bit
}
hex_chars_to_uint8((char*)asciiCardId, protocol->data);
}
static bool protocol_pac_stanley_can_be_decoded(ProtocolPACStanley* protocol) {
// Check preamble
if(bit_lib_get_bits(protocol->encoded_data, 0, 8) != 0b11111111) return false;
if(bit_lib_get_bit(protocol->encoded_data, 8) != 0) return false;
if(bit_lib_get_bit(protocol->encoded_data, 9) != 0) return false;
if(bit_lib_get_bit(protocol->encoded_data, 10) != 1) return false;
if(bit_lib_get_bits(protocol->encoded_data, 11, 8) != 0b00000010) return false;
// Check next preamble
if(bit_lib_get_bits(protocol->encoded_data, 128, 8) != 0b11111111) return false;
// Checksum
uint8_t checksum = 0;
uint8_t stripped_byte;
for(size_t idx = 0; idx < 9; idx++) {
uint8_t byte = bit_lib_reverse_8_fast(bit_lib_get_bits(
protocol->encoded_data,
PAC_STANLEY_DATA_START_INDEX + (PAC_STANLEY_BYTE_LENGTH * idx),
8));
stripped_byte = byte & 0x7F; // discard the parity bit
if(bit_lib_test_parity_32(stripped_byte, BitLibParityOdd) != (byte & 0x80) >> 7) {
return false;
}
if(idx < 8) checksum ^= stripped_byte;
}
if(stripped_byte != checksum) return false;
return true;
}
void protocol_pac_stanley_decoder_start(ProtocolPACStanley* protocol) {
memset(protocol->data, 0, PAC_STANLEY_DECODED_DATA_SIZE);
protocol->inverted = false;
protocol->got_preamble = false;
}
bool protocol_pac_stanley_decoder_feed(ProtocolPACStanley* protocol, bool level, uint32_t duration) {
bool pushed = false;
if(duration > PAC_STANLEY_MAX_TIME) return false;
uint8_t pulses = (uint8_t)round((float)duration / PAC_STANLEY_CYCLE_LENGTH);
// Handle last stopbit & preamble (1 sb, 8 bit preamble)
if(pulses >= 9 && !protocol->got_preamble) {
pulses = 8;
protocol->got_preamble = true;
protocol->inverted = !level;
} else if(pulses >= 9 && protocol->got_preamble) {
protocol->got_preamble = false;
} else if(pulses == 0 && duration > PAC_STANLEY_MIN_TIME) {
pulses = 1;
}
if(pulses) {
for(uint8_t i = 0; i < pulses; i++) {
bit_lib_push_bit(
protocol->encoded_data,
PAC_STANLEY_ENCODED_BYTE_FULL_SIZE,
level ^ protocol->inverted);
}
pushed = true;
}
if(pushed && protocol_pac_stanley_can_be_decoded(protocol)) {
protocol_pac_stanley_decode(protocol);
return true;
}
return false;
}
bool protocol_pac_stanley_encoder_start(ProtocolPACStanley* protocol) {
memset(protocol->encoded_data, 0, PAC_STANLEY_ENCODED_BYTE_SIZE);
uint8_t idbytes[10];
idbytes[0] = '2';
idbytes[1] = '0';
uint8_to_hex_chars(protocol->data, &idbytes[2], 8);
// insert start and stop bits
for(size_t i = 0; i < 16; i++) protocol->encoded_data[i] = 0x40 >> (i + 3) % 5 * 2;
protocol->encoded_data[0] = 0xFF; // mark + stop
protocol->encoded_data[1] = 0x20; // start + reflect8(STX)
uint8_t checksum = 0;
for(size_t i = 2; i < 13; i++) {
uint8_t shift = 7 - (i + 3) % 4 * 2;
uint8_t index = i + (i - 1) / 4;
uint16_t pattern;
if(i < 12) {
pattern = bit_lib_reverse_8_fast(idbytes[i - 2]);
pattern |= bit_lib_test_parity_32(pattern, BitLibParityOdd);
if(i > 3) checksum ^= idbytes[i - 2];
} else {
pattern = (bit_lib_reverse_8_fast(checksum) & 0xFE) |
(bit_lib_test_parity_32(checksum, BitLibParityOdd));
}
pattern <<= shift;
protocol->encoded_data[index] |= pattern >> 8 & 0xFF;
protocol->encoded_data[index + 1] |= pattern & 0xFF;
}
protocol->encoded_index = 0;
return true;
}
LevelDuration protocol_pac_stanley_encoder_yield(ProtocolPACStanley* protocol) {
uint16_t length = PAC_STANLEY_CLOCKS_IN_US;
bool bit = bit_lib_get_bit(protocol->encoded_data, protocol->encoded_index);
bit_lib_increment_index(protocol->encoded_index, PAC_STANLEY_ENCODED_BIT_SIZE);
while(bit_lib_get_bit(protocol->encoded_data, protocol->encoded_index) == bit) {
length += PAC_STANLEY_CLOCKS_IN_US;
bit_lib_increment_index(protocol->encoded_index, PAC_STANLEY_ENCODED_BIT_SIZE);
}
return level_duration_make(bit, length);
}
bool protocol_pac_stanley_write_data(ProtocolPACStanley* protocol, void* data) {
LFRFIDWriteRequest* request = (LFRFIDWriteRequest*)data;
bool result = false;
protocol_pac_stanley_encoder_start(protocol);
if(request->write_type == LFRFIDWriteTypeT5577) {
request->t5577.block[0] = LFRFID_T5577_MODULATION_DIRECT | LFRFID_T5577_BITRATE_RF_32 |
(4 << 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);
request->t5577.block[3] = bit_lib_get_bits_32(protocol->encoded_data, 64, 32);
request->t5577.block[4] = bit_lib_get_bits_32(protocol->encoded_data, 96, 32);
request->t5577.blocks_to_write = 5;
result = true;
}
return result;
}
void protocol_pac_stanley_render_data(ProtocolPACStanley* protocol, string_t result) {
uint8_t* data = protocol->data;
string_printf(result, "CIN: %02X%02X%02X%02X", data[0], data[1], data[2], data[3]);
}
const ProtocolBase protocol_pac_stanley = {
.name = "PAC/Stanley",
.manufacturer = "N/A",
.data_size = PAC_STANLEY_DECODED_DATA_SIZE,
.features = LFRFIDFeatureASK,
.validate_count = 3,
.alloc = (ProtocolAlloc)protocol_pac_stanley_alloc,
.free = (ProtocolFree)protocol_pac_stanley_free,
.get_data = (ProtocolGetData)protocol_pac_stanley_get_data,
.decoder =
{
.start = (ProtocolDecoderStart)protocol_pac_stanley_decoder_start,
.feed = (ProtocolDecoderFeed)protocol_pac_stanley_decoder_feed,
},
.encoder =
{
.start = (ProtocolEncoderStart)protocol_pac_stanley_encoder_start,
.yield = (ProtocolEncoderYield)protocol_pac_stanley_encoder_yield,
},
.render_data = (ProtocolRenderData)protocol_pac_stanley_render_data,
.render_brief_data = (ProtocolRenderData)protocol_pac_stanley_render_data,
.write_data = (ProtocolWriteData)protocol_pac_stanley_write_data,
};