unleashed-firmware/lib/nfc_protocols/mifare_classic.c
2022-04-22 15:41:10 +03:00

313 lines
9.4 KiB
C

#include "mifare_classic.h"
#include "nfca.h"
#include "nfc_util.h"
// Algorithm from https://github.com/RfidResearchGroup/proxmark3.git
#define TAG "MfClassic"
#define MF_CLASSIC_AUTH_KEY_A_CMD (0x60U)
#define MF_CLASSIC_AUTH_KEY_B_CMD (0x61U)
#define MF_CLASSIC_READ_SECT_CMD (0x30)
static uint8_t mf_classic_get_first_block_num_of_sector(uint8_t sector) {
furi_assert(sector < 40);
if(sector < 32) {
return sector * 4;
} else {
return 32 * 4 + (sector - 32) * 16;
}
}
static uint8_t mf_classic_get_blocks_num_in_sector(uint8_t sector) {
furi_assert(sector < 40);
return sector < 32 ? 4 : 16;
}
uint8_t mf_classic_get_total_sectors_num(MfClassicReader* reader) {
furi_assert(reader);
if(reader->type == MfClassicType1k) {
return MF_CLASSIC_1K_TOTAL_SECTORS_NUM;
} else if(reader->type == MfClassicType4k) {
return MF_CLASSIC_4K_TOTAL_SECTORS_NUM;
} else {
return 0;
}
}
bool mf_classic_check_card_type(uint8_t ATQA0, uint8_t ATQA1, uint8_t SAK) {
if((ATQA0 == 0x44 || ATQA0 == 0x04) && (SAK == 0x08)) {
return true;
} else if((ATQA0 == 0x42 || ATQA0 == 0x02) && (SAK == 0x18)) {
return true;
} else {
return false;
}
}
bool mf_classic_get_type(
uint8_t* uid,
uint8_t uid_len,
uint8_t ATQA0,
uint8_t ATQA1,
uint8_t SAK,
MfClassicReader* reader) {
furi_assert(uid);
furi_assert(reader);
memset(reader, 0, sizeof(MfClassicReader));
if((ATQA0 == 0x44 || ATQA0 == 0x04) && (SAK == 0x08)) {
reader->type = MfClassicType1k;
} else if((ATQA0 == 0x42 || ATQA0 == 0x02) && (SAK == 0x18)) {
reader->type = MfClassicType4k;
} else {
return false;
}
uint8_t* cuid_start = uid;
if(uid_len == 7) {
cuid_start = &uid[3];
}
reader->cuid = (cuid_start[0] << 24) | (cuid_start[1] << 16) | (cuid_start[2] << 8) |
(cuid_start[3]);
return true;
}
void mf_classic_reader_add_sector(
MfClassicReader* reader,
uint8_t sector,
uint64_t key_a,
uint64_t key_b) {
furi_assert(reader);
furi_assert(sector < MF_CLASSIC_SECTORS_MAX);
furi_assert((key_a != MF_CLASSIC_NO_KEY) || (key_b != MF_CLASSIC_NO_KEY));
if(reader->sectors_to_read < MF_CLASSIC_SECTORS_MAX - 1) {
reader->sector_reader[reader->sectors_to_read].key_a = key_a;
reader->sector_reader[reader->sectors_to_read].key_b = key_b;
reader->sector_reader[reader->sectors_to_read].sector_num = sector;
reader->sectors_to_read++;
}
}
void mf_classic_auth_init_context(MfClassicAuthContext* auth_ctx, uint32_t cuid, uint8_t sector) {
furi_assert(auth_ctx);
auth_ctx->cuid = cuid;
auth_ctx->sector = sector;
auth_ctx->key_a = MF_CLASSIC_NO_KEY;
auth_ctx->key_b = MF_CLASSIC_NO_KEY;
}
static bool mf_classic_auth(
FuriHalNfcTxRxContext* tx_rx,
uint32_t cuid,
uint32_t block,
uint64_t key,
MfClassicKey key_type,
Crypto1* crypto) {
bool auth_success = false;
memset(tx_rx, 0, sizeof(FuriHalNfcTxRxContext));
do {
if(key_type == MfClassicKeyA) {
tx_rx->tx_data[0] = MF_CLASSIC_AUTH_KEY_A_CMD;
} else {
tx_rx->tx_data[0] = MF_CLASSIC_AUTH_KEY_B_CMD;
}
tx_rx->tx_data[1] = block;
tx_rx->tx_rx_type = FuriHalNfcTxRxTypeRxNoCrc;
tx_rx->tx_bits = 2 * 8;
if(!furi_hal_nfc_tx_rx(tx_rx, 5)) break;
uint32_t nt = (uint32_t)nfc_util_bytes2num(tx_rx->rx_data, 4);
crypto1_init(crypto, key);
crypto1_word(crypto, nt ^ cuid, 0);
uint8_t nr[4] = {};
nfc_util_num2bytes(prng_successor(DWT->CYCCNT, 32), 4, nr);
for(uint8_t i = 0; i < 4; i++) {
tx_rx->tx_data[i] = crypto1_byte(crypto, nr[i], 0) ^ nr[i];
tx_rx->tx_parity[0] |=
(((crypto1_filter(crypto->odd) ^ nfc_util_odd_parity8(nr[i])) & 0x01) << (7 - i));
}
nt = prng_successor(nt, 32);
for(uint8_t i = 4; i < 8; i++) {
nt = prng_successor(nt, 8);
tx_rx->tx_data[i] = crypto1_byte(crypto, 0x00, 0) ^ (nt & 0xff);
tx_rx->tx_parity[0] |=
(((crypto1_filter(crypto->odd) ^ nfc_util_odd_parity8(nt & 0xff)) & 0x01)
<< (7 - i));
}
tx_rx->tx_rx_type = FuriHalNfcTxRxTypeRaw;
tx_rx->tx_bits = 8 * 8;
if(!furi_hal_nfc_tx_rx(tx_rx, 5)) break;
if(tx_rx->rx_bits == 32) {
crypto1_word(crypto, 0, 0);
auth_success = true;
}
} while(false);
return auth_success;
}
bool mf_classic_auth_attempt(
FuriHalNfcTxRxContext* tx_rx,
MfClassicAuthContext* auth_ctx,
uint64_t key) {
furi_assert(tx_rx);
furi_assert(auth_ctx);
bool found_key = false;
bool need_halt = (auth_ctx->key_a == MF_CLASSIC_NO_KEY) &&
(auth_ctx->key_b == MF_CLASSIC_NO_KEY);
Crypto1 crypto;
if(auth_ctx->key_a == MF_CLASSIC_NO_KEY) {
// Try AUTH with key A
if(mf_classic_auth(
tx_rx,
auth_ctx->cuid,
mf_classic_get_first_block_num_of_sector(auth_ctx->sector),
key,
MfClassicKeyA,
&crypto)) {
auth_ctx->key_a = key;
found_key = true;
}
}
if(need_halt) {
furi_hal_nfc_sleep();
furi_hal_nfc_activate_nfca(300, &auth_ctx->cuid);
}
if(auth_ctx->key_b == MF_CLASSIC_NO_KEY) {
// Try AUTH with key B
if(mf_classic_auth(
tx_rx,
auth_ctx->cuid,
mf_classic_get_first_block_num_of_sector(auth_ctx->sector),
key,
MfClassicKeyB,
&crypto)) {
auth_ctx->key_b = key;
found_key = true;
}
}
return found_key;
}
bool mf_classic_read_block(
FuriHalNfcTxRxContext* tx_rx,
Crypto1* crypto,
uint8_t block_num,
MfClassicBlock* block) {
furi_assert(tx_rx);
furi_assert(crypto);
furi_assert(block_num < MF_CLASSIC_TOTAL_BLOCKS_MAX);
furi_assert(block);
bool read_block_success = false;
uint8_t plain_cmd[4] = {MF_CLASSIC_READ_SECT_CMD, block_num, 0x00, 0x00};
nfca_append_crc16(plain_cmd, 2);
memset(tx_rx, 0, sizeof(FuriHalNfcTxRxContext));
for(uint8_t i = 0; i < 4; i++) {
tx_rx->tx_data[i] = crypto1_byte(crypto, 0x00, 0) ^ plain_cmd[i];
tx_rx->tx_parity[0] |=
((crypto1_filter(crypto->odd) ^ nfc_util_odd_parity8(plain_cmd[i])) & 0x01) << (7 - i);
}
tx_rx->tx_bits = 4 * 9;
tx_rx->tx_rx_type = FuriHalNfcTxRxTypeRaw;
if(furi_hal_nfc_tx_rx(tx_rx, 50)) {
if(tx_rx->rx_bits == 8 * 18) {
for(uint8_t i = 0; i < 18; i++) {
block->value[i] = crypto1_byte(crypto, 0, 0) ^ tx_rx->rx_data[i];
}
read_block_success = true;
}
}
return read_block_success;
}
bool mf_classic_read_sector(
FuriHalNfcTxRxContext* tx_rx,
Crypto1* crypto,
MfClassicSectorReader* sector_reader,
MfClassicSector* sector) {
furi_assert(tx_rx);
furi_assert(sector_reader);
furi_assert(sector);
uint32_t cuid = 0;
uint64_t key;
MfClassicKey key_type;
uint8_t first_block;
bool sector_read = false;
furi_hal_nfc_sleep();
do {
// Activate card
if(!furi_hal_nfc_activate_nfca(200, &cuid)) break;
first_block = mf_classic_get_first_block_num_of_sector(sector_reader->sector_num);
if(sector_reader->key_a != MF_CLASSIC_NO_KEY) {
key = sector_reader->key_a;
key_type = MfClassicKeyA;
} else if(sector_reader->key_b != MF_CLASSIC_NO_KEY) {
key = sector_reader->key_b;
key_type = MfClassicKeyB;
} else {
break;
}
// Auth to first block in sector
if(!mf_classic_auth(tx_rx, cuid, first_block, key, key_type, crypto)) break;
sector->total_blocks = mf_classic_get_blocks_num_in_sector(sector_reader->sector_num);
// Read blocks
for(uint8_t i = 0; i < sector->total_blocks; i++) {
mf_classic_read_block(tx_rx, crypto, first_block + i, &sector->block[i]);
}
// Save sector keys in last block
if(sector_reader->key_a != MF_CLASSIC_NO_KEY) {
nfc_util_num2bytes(
sector_reader->key_a, 6, &sector->block[sector->total_blocks - 1].value[0]);
}
if(sector_reader->key_b != MF_CLASSIC_NO_KEY) {
nfc_util_num2bytes(
sector_reader->key_b, 6, &sector->block[sector->total_blocks - 1].value[10]);
}
sector_read = true;
} while(false);
return sector_read;
}
uint8_t mf_classic_read_card(
FuriHalNfcTxRxContext* tx_rx,
MfClassicReader* reader,
MfClassicData* data) {
furi_assert(tx_rx);
furi_assert(reader);
furi_assert(data);
uint8_t sectors_read = 0;
data->type = reader->type;
MfClassicSector temp_sector = {};
for(uint8_t i = 0; i < reader->sectors_to_read; i++) {
if(mf_classic_read_sector(
tx_rx, &reader->crypto, &reader->sector_reader[i], &temp_sector)) {
uint8_t first_block =
mf_classic_get_first_block_num_of_sector(reader->sector_reader[i].sector_num);
for(uint8_t j = 0; j < temp_sector.total_blocks; j++) {
data->block[first_block + j] = temp_sector.block[j];
}
sectors_read++;
}
}
return sectors_read;
}