From 2150f18496a3d8f683ba4b6a54dd213a0009e69d Mon Sep 17 00:00:00 2001 From: Zachary Weiss Date: Tue, 9 Apr 2024 20:19:27 -0400 Subject: [PATCH] Struct&var refactor for clarity --- .../nfc/plugins/supported_cards/charliecard.c | 116 +++++++++--------- 1 file changed, 61 insertions(+), 55 deletions(-) diff --git a/applications/main/nfc/plugins/supported_cards/charliecard.c b/applications/main/nfc/plugins/supported_cards/charliecard.c index 81b9bb8976..136cfeb270 100644 --- a/applications/main/nfc/plugins/supported_cards/charliecard.c +++ b/applications/main/nfc/plugins/supported_cards/charliecard.c @@ -94,7 +94,7 @@ // timestep is one minute #define CHARLIE_TIME_DELTA_SECS 60 #define CHARLIE_END_VALID_DELTA_SECS 60 * 8 -#define CHARLIE_N_TRIP_HISTORY 10 +#define CHARLIE_N_TRANSACTION_HISTORY 10 #define CHARLIE_N_PASSES 4 typedef struct { @@ -147,7 +147,7 @@ typedef struct { uint8_t g_flag; Money fare; uint16_t f_flag; -} Trip; +} Transaction; typedef struct { bool valid; @@ -206,7 +206,7 @@ static const IdMapping charliecard_types[] = { {.id = 166, .name = "30 Day Commuter Rail Zone 1A Pass"}, {.id = 167, .name = "30 Day Commuter Rail Zone 1 Pass"}, {.id = 168, .name = "30 Day Commuter Rail Zone 2 Pass"}, - {.id = 169, .name = "30 Day Commuter Rail Zone 3 Pass"}, + {.id = 169, .name = "30 Day ComZmuter Rail Zone 3 Pass"}, {.id = 170, .name = "30 Day Commuter Rail Zone 4 Pass"}, {.id = 171, .name = "30 Day Commuter Rail Zone 5 Pass"}, {.id = 172, .name = "30 Day Commuter Rail Zone 6 Pass"}, @@ -717,7 +717,11 @@ static Pass // the uk1 and date fields, and is always set to 1 regardless // same is true of type & end-validity split found in balance sector // - // + // likely fields incl + // — type #, + // — a secondary date field (eg start/end, end validity or normal format) + // — ID of FVM from which the pass was loaded + // check for empty, if so, return struct filled w/ 0s // (incl "valid" field: hence, "valid" is false-y) if(pos_to_num(data, sector_num, block_num, byte_num, 6) == 0x002000000000) { @@ -727,7 +731,7 @@ static Pass // const DateTime start = date_parse(data, sector_num, block_num, byte_num + 1); const uint16_t pre = pos_to_num(data, sector_num, block_num, byte_num, 2) >> 6; - const uint16_t post = pos_to_num(data, sector_num, block_num, byte_num + 4, 2); + const uint16_t post = (pos_to_num(data, sector_num, block_num, byte_num + 4, 2) >> 2) & 0x3ff; // these values make sense for a date, but implied position of type // before end validity, as seen in balance sector, doesn't seem @@ -740,8 +744,9 @@ static Pass return (Pass){true, pre, post, date}; } -static Trip trip_parse(const MfClassicData* data, uint8_t sector, uint8_t block, uint8_t byte) { - /* This function parses individual trips. Each trip packs 7 bytes, stored as follows: +static Transaction + transaction_parse(const MfClassicData* data, uint8_t sector, uint8_t block, uint8_t byte) { + /* This function parses individual transactions. Each transaction packs 7 bytes, stored as follows: 0 1 2 3 4 5 6 +----.----.----+----.--+-+----.----+ @@ -753,23 +758,23 @@ static Trip trip_parse(const MfClassicData* data, uint8_t sector, uint8_t block, Gate ID ("loc") is only the first 13 bits of 0x3:0x5, the final three bits appear to be flags ("f"). Least significant flag bit seems to indicate: - — When f & 1 == 0, fare (the amount by which balance is decremented) - — When f & 1 == 1, refill (the amount by which balance is incremented) + — When f & 1 == 1, fare (the amount by which balance is decremented) + — When f & 1 == 0, refill (the amount by which balance is incremented) MSB (sign bit) of amt seems to serve the same role, just inverted, ie - — When amt & 0x8000 == 0x8000, fare - — When amt & 0x8000 == 0, refill + — When amt & 0x8000 == 0, fare + — When amt & 0x8000 == 0x8000, refill Remaining unknown bits: — f & 0b100 — f & 0b010 - — amt & 1; does not seem to correspond with card type, last trip, first trip, refill v. fare, etc + — amt & 1; does not seem to correspond with card type, last transaction, first transaction, refill v. fare, etc */ const DateTime date = date_parse(data, sector, block, byte); const uint16_t gate = pos_to_num(data, sector, block, byte + 3, 2) >> 3; const uint8_t g_flag = pos_to_num(data, sector, block, byte + 3, 2) & 0b111; const Money fare = money_parse(data, sector, block, byte + 5); const uint16_t f_flag = pos_to_num(data, sector, block, byte + 5, 2) & 0x8001; - return (Trip){date, gate, g_flag, fare, f_flag}; + return (Transaction){date, gate, g_flag, fare, f_flag}; } // ********************************************************** @@ -810,10 +815,10 @@ static CounterSector counter_sector_parse(const MfClassicData* data) { // 0x060 | uses2 | uk | ... 00 00 ... | // +----.----+----+----.----.----.----.----.----.----.----.----.----.----.----.----+ // - // uk := "unknown"; if nonzero, seems to only occupy the first 4 bits (ie, mask w/ 0xF0), + // uk := "unknown"; if nonzero, seems to only occupy the first 4 bits (ie, uk & 0xF0 == uk), // with the remaining 4 zero - // Card has two transaction sectors (2 & 3) containing balance data, with two + // Card has two sectors (2 & 3) containing balance data, with two // corresponding trip counters in 0x50:0x51 & 0x60:0x61 (sector 1, byte 0:1 of blocks 1 & 2). // The *lower* of the two values *minus one* is the true use count, @@ -866,7 +871,7 @@ static Pass* passes_parse(const MfClassicData* data) { // // 0 1 2 3 4 5 6 7 8 9 A B C D E F // +----.----.----.----.----.----+----+----.----.----.----.----.----+----+----.----+ - // 0x100 | pass0? | 00 | pass1? | 00 | crc | 0x140 + // 0x100 | pass0/2? | 00 | pass1/3? | 00 | crc | 0x140 // +----.----.----.----.----.----+----+----.----.----.----.----.----+----+----.----+ // 0x110 | ... 00 00 ... | crc | 0x150 // +----.----.----.----.----.----.----.----.----.----.----.----.----.----+----.----+ @@ -886,16 +891,16 @@ static Pass* passes_parse(const MfClassicData* data) { return passes; } -static Trip* trips_parse(const MfClassicData* data) { +static Transaction* transactions_parse(const MfClassicData* data) { // Transaction history (Sectors 6–7) // // 0 1 2 3 4 5 6 7 8 9 A B C D E F // +----.----.----.----.----.----.----+----.----.----.----.----.----.----+----.----+ - // 0x180 | trip0 | trip1 | crc | + // 0x180 | transaction0 | transaction1 | crc | // +----.----.----.----.----.----.----+----.----.----.----.----.----.----+----.----+ // ... ... ... ... // +----.----.----.----.----.----.----+----.----.----.----.----.----.----+----.----+ - // 0x1D0 | trip8 | trip9 | crc | + // 0x1D0 | transaction8 | transaction9 | crc | // +----.----.----.----.----.----.----+----.----.----.----.----.----.----+----.----+ // 0x1E0 | ... 00 00 ... | crc | // +----.----.----.----.----.----.----.----.----.----.----.----.----.----+----.----+ @@ -903,20 +908,20 @@ static Trip* trips_parse(const MfClassicData* data) { // Transactions are not sorted, rather, appear to get overwritten // sequentially. (eg, sorted modulo array rotation) - Trip* trips = malloc(sizeof(Trip) * CHARLIE_N_TRIP_HISTORY); + Transaction* transactions = malloc(sizeof(Transaction) * CHARLIE_N_TRANSACTION_HISTORY); - // Parse each trip field using some modular math magic to get the offsets: - // move from sector 6 -> 7 after the first 6 trips - // move a block within a given sector every 2 trips, reset every 3 blocks (as sector has changed) + // Parse each transaction field using some modular math magic to get the offsets: + // move from sector 6 -> 7 after the first 6 transactions + // move a block within a given sector every 2 transactions, reset every 3 blocks (as sector has changed) // alternate between a start byte of 0 and 7 with every iteration - for(size_t i = 0; i < CHARLIE_N_TRIP_HISTORY; i++) { - trips[i] = trip_parse(data, 6 + (i / 6), (i / 2) % 3, (i % 2) * 7); + for(size_t i = 0; i < CHARLIE_N_TRANSACTION_HISTORY; i++) { + transactions[i] = transaction_parse(data, 6 + (i / 6), (i / 2) % 3, (i % 2) * 7); } // Iterate through the array to find the maximum (newest) date value int max_idx = 0; - for(int i = 1; i < CHARLIE_N_TRIP_HISTORY; i++) { - if(dt_ge(trips[i].date, trips[max_idx].date)) { + for(int i = 1; i < CHARLIE_N_TRANSACTION_HISTORY; i++) { + if(dt_ge(transactions[i].date, transactions[max_idx].date)) { max_idx = i; } } @@ -924,24 +929,24 @@ static Trip* trips_parse(const MfClassicData* data) { // Sort by rotating for(int r = 0; r < (max_idx + 1); r++) { // Store the first element - Trip temp = trips[0]; + Transaction temp = transactions[0]; // Shift elements to the left - for(int i = 0; i < CHARLIE_N_TRIP_HISTORY - 1; i++) { - trips[i] = trips[i + 1]; + for(int i = 0; i < CHARLIE_N_TRANSACTION_HISTORY - 1; i++) { + transactions[i] = transactions[i + 1]; } // Move the first element to the last - trips[CHARLIE_N_TRIP_HISTORY - 1] = temp; + transactions[CHARLIE_N_TRANSACTION_HISTORY - 1] = temp; } // Reverse order, such that newest is first, oldest last - for(int i = 0; i < CHARLIE_N_TRIP_HISTORY / 2; i++) { + for(int i = 0; i < CHARLIE_N_TRANSACTION_HISTORY / 2; i++) { // Swap elements at index i and size - i - 1 - Trip temp = trips[i]; - trips[i] = trips[CHARLIE_N_TRIP_HISTORY - i - 1]; - trips[CHARLIE_N_TRIP_HISTORY - i - 1] = temp; + Transaction temp = transactions[i]; + transactions[i] = transactions[CHARLIE_N_TRANSACTION_HISTORY - i - 1]; + transactions[CHARLIE_N_TRANSACTION_HISTORY - i - 1] = temp; } - return trips; + return transactions; } /* @@ -976,12 +981,12 @@ static DateTime expiry(DateTime iss) { return exp; } -static bool expired(DateTime expiry, DateTime last_trip) { +static bool expired(DateTime expiry, DateTime last_transaction) { // if a card has sat unused for >2 years, expired (verify this claim?) // else expired if current date > expiry date uint32_t ts_exp = datetime_datetime_to_timestamp(&expiry); - uint32_t ts_last = datetime_datetime_to_timestamp(&last_trip); + uint32_t ts_last = datetime_datetime_to_timestamp(&last_transaction); uint32_t ts_now = time_now(); return (ts_exp <= ts_now) | ((ts_now - ts_last) >= (2 * 365 * 24 * 60 * 60)); @@ -1020,7 +1025,8 @@ void type_format_cat(FuriString* out, uint16_t type) { void pass_format_cat(FuriString* out, Pass pass) { furi_string_cat_printf(out, "\n-Pre: %b", pass.pre); // type_format_cat(out, pass.type); - furi_string_cat_printf(out, "\n-Post: %b", pass.post); + furi_string_cat_printf(out, "\n-Post: "); + type_format_cat(out, pass.post); // locale_format_dt_cat(out, &pass.start); furi_string_cat_printf(out, "\n-Date: "); locale_format_dt_cat(out, &pass.date); @@ -1055,37 +1061,37 @@ void money_format_cat(FuriString* out, Money money) { furi_string_cat_printf(out, "$%u.%02u", money.dollars, money.cents); } -void trip_format_cat(FuriString* out, Trip trip) { +void transaction_format_cat(FuriString* out, Transaction transaction) { const char* sep = " "; const char* sta; - locale_format_dt_cat(out, &trip.date); - furi_string_cat_printf(out, "\n%s", !!(trip.g_flag & 0x1) ? "-" : "+"); - money_format_cat(out, trip.fare); - if(!!(trip.g_flag & 0x1) && (trip.fare.dollars == FARE_BUS.dollars) && - (trip.fare.cents == FARE_BUS.cents)) { + locale_format_dt_cat(out, &transaction.date); + furi_string_cat_printf(out, "\n%s", !!(transaction.g_flag & 0x1) ? "-" : "+"); + money_format_cat(out, transaction.fare); + if(!!(transaction.g_flag & 0x1) && (transaction.fare.dollars == FARE_BUS.dollars) && + (transaction.fare.cents == FARE_BUS.cents)) { // if not a refill, and the fare amount is equal to bus fare (any better approach? flag bits for modality?) // format for bus — supposedly some correlation between gate ID & bus #, haven't investigated - furi_string_cat_printf(out, "%s#%u", sep, trip.gate); - } else if(get_map_item(trip.gate, charliecard_fare_gate_ids, kNumFareGateIds, &sta)) { + furi_string_cat_printf(out, "%s#%u", sep, transaction.gate); + } else if(get_map_item(transaction.gate, charliecard_fare_gate_ids, kNumFareGateIds, &sta)) { // station found in fare gate ID map, append station name furi_string_cat_str(out, sep); furi_string_cat_str(out, sta); } else { // no found station in fare gate ID map & not a bus, just print ID w/o add'l info - furi_string_cat_printf(out, "%s#%u", sep, trip.gate); + furi_string_cat_printf(out, "%s#%u", sep, transaction.gate); } // print flags for debugging purposes if(is_debug()) { - furi_string_cat_printf(out, "%s%x%s%x", sep, trip.g_flag, sep, trip.f_flag); + furi_string_cat_printf(out, "%s%x%s%x", sep, transaction.g_flag, sep, transaction.f_flag); } } -void trips_format_cat(FuriString* out, Trip* trips) { +void transactions_format_cat(FuriString* out, Transaction* transactions) { furi_string_cat_printf(out, "\nTransactions:"); - for(size_t i = 0; i < CHARLIE_N_TRIP_HISTORY; i++) { + for(size_t i = 0; i < CHARLIE_N_TRANSACTION_HISTORY; i++) { furi_string_cat_printf(out, "\n"); - trip_format_cat(out, trips[i]); + transaction_format_cat(out, transactions[i]); furi_string_cat_printf(out, "\n"); } } @@ -1126,7 +1132,7 @@ static bool charliecard_parse(const NfcDevice* device, FuriString* parsed_data) const BalanceSector balance_sector = balance_sector_parse(data, counter_sector.active_balance_sector); Pass* passes = passes_parse(data); - Trip* trips = trips_parse(data); + Transaction* transactions = transactions_parse(data); // print/append card data furi_string_cat_printf(parsed_data, "\e#CharlieCard"); @@ -1152,8 +1158,8 @@ static bool charliecard_parse(const NfcDevice* device, FuriString* parsed_data) passes_format_cat(parsed_data, passes); free(passes); - trips_format_cat(parsed_data, trips); - free(trips); + transactions_format_cat(parsed_data, transactions); + free(transactions); parsed = true; } while(false);