liz/flipperzero-firmware
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NFC: fixes & improvements (#897)

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* nfc: (mf_ul) fix overflow while reading
* nfc: (mf_ul) fix FAST_READ command emulation
* nfc: (mf_ul) implement non-strict PWD_AUTH command emulation for NTAG21x
* nfc: (mf_ul) improve emulation stability by removing frequent furi_hal_console_put() calls that cause delays or something
* nfc: (mf_ul) remove calls to blocking functions from emulation worker

Co-authored-by: あく <alleteam@gmail.com>
This commit is contained in:
ghettorce
2021-12-15 21:27:25 +03:00
committed by GitHub
parent 757ea073a8
commit de006aa06a
3 changed files with 78 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
applications/nfc/nfc_worker.c
View File

@@ -613,6 +613,9 @@ void nfc_worker_emulate_mifare_ul(NfcWorker* nfc_worker) {
// Setup emulation parameters from mifare ultralight data structure
mf_ul_prepare_emulation(&mf_ul_emulate, &data->mf_ul_data);
while(nfc_worker->state == NfcWorkerStateEmulateMifareUl) {
// WARNING
// DO NOT call any blocking functions (e.g. FURI_LOG_*) in this loop,
// as any delay will negatively affect the stability of the emulation.
if(furi_hal_nfc_listen(
data->nfc_data.uid,
data->nfc_data.uid_len,
@@ -620,7 +623,6 @@ void nfc_worker_emulate_mifare_ul(NfcWorker* nfc_worker) {
data->nfc_data.sak,
true,
200)) {
FURI_LOG_D(TAG, "Anticollision passed");
if(furi_hal_nfc_get_first_frame(&rx_buff, &rx_len)) {
// Data exchange loop
while(nfc_worker->state == NfcWorkerStateEmulateMifareUl) {
@@ -632,17 +634,14 @@ void nfc_worker_emulate_mifare_ul(NfcWorker* nfc_worker) {
if(err == ERR_NONE) {
continue;
} else {
FURI_LOG_E(TAG, "Communication error: %d", err);
break;
}
} else {
FURI_LOG_W(TAG, "Not valid command: %02X", rx_buff[0]);
furi_hal_nfc_deactivate();
break;
}
}
} else {
FURI_LOG_W(TAG, "Error in 1st data exchange");
furi_hal_nfc_deactivate();
}
}
@@ -653,7 +652,6 @@ void nfc_worker_emulate_mifare_ul(NfcWorker* nfc_worker) {
nfc_worker->callback(nfc_worker->context);
}
}
FURI_LOG_W(TAG, "Can't find reader");
osThreadYield();
}
}

71
lib/nfc_protocols/mifare_ultralight.c
View File

@@ -53,9 +53,14 @@ uint16_t mf_ul_prepare_read(uint8_t* dest, uint8_t start_page) {
}
void mf_ul_parse_read_response(uint8_t* buff, uint16_t page_addr, MifareUlDevice* mf_ul_read) {
mf_ul_read->pages_readed += 4;
uint8_t pages_read = 4;
uint8_t page_read_count = mf_ul_read->pages_readed + pages_read;
if(page_read_count > mf_ul_read->pages_to_read) {
pages_read -= page_read_count - mf_ul_read->pages_to_read;
}
mf_ul_read->pages_readed += pages_read;
mf_ul_read->data.data_size = mf_ul_read->pages_readed * 4;
memcpy(&mf_ul_read->data.data[page_addr * 4], buff, 16);
memcpy(&mf_ul_read->data.data[page_addr * 4], buff, pages_read * 4);
}
uint16_t mf_ul_prepare_fast_read(uint8_t* dest, uint8_t start_page, uint8_t end_page) {
@@ -140,6 +145,7 @@ uint16_t mf_ul_prepare_write(uint8_t* dest, uint16_t page_addr, uint32_t data) {
void mf_ul_prepare_emulation(MifareUlDevice* mf_ul_emulate, MifareUlData* data) {
mf_ul_emulate->data = *data;
mf_ul_emulate->auth_data = NULL;
mf_ul_emulate->data_changed = false;
if(data->version.storage_size == 0) {
mf_ul_emulate->type = MfUltralightTypeUnknown;
@@ -150,6 +156,37 @@ void mf_ul_prepare_emulation(MifareUlDevice* mf_ul_emulate, MifareUlData* data)
} else if(data->version.storage_size == 0x0E) {
mf_ul_emulate->type = MfUltralightTypeUL21;
mf_ul_emulate->support_fast_read = true;
} else if(data->version.storage_size == 0x0F) {
mf_ul_emulate->type = MfUltralightTypeNTAG213;
mf_ul_emulate->support_fast_read = true;
} else if(data->version.storage_size == 0x11) {
mf_ul_emulate->type = MfUltralightTypeNTAG215;
mf_ul_emulate->support_fast_read = true;
} else if(data->version.storage_size == 0x13) {
mf_ul_emulate->type = MfUltralightTypeNTAG216;
mf_ul_emulate->support_fast_read = true;
}
if(mf_ul_emulate->type >= MfUltralightTypeNTAG213) {
uint16_t pwd_page = (data->data_size / 4) - 2;
mf_ul_emulate->auth_data = (MifareUlAuthData*)&data->data[pwd_page * 4];
}
}
void mf_ul_protect_auth_data_on_read_command(
uint8_t* tx_buff,
uint8_t start_page,
uint8_t end_page,
MifareUlDevice* mf_ul_emulate) {
if(mf_ul_emulate->type >= MfUltralightTypeNTAG213) {
uint8_t pwd_page = (mf_ul_emulate->data.data_size / 4) - 2;
uint8_t pack_page = pwd_page + 1;
if((start_page <= pwd_page) && (end_page >= pwd_page)) {
memset(&tx_buff[(pwd_page - start_page) * 4], 0, 4);
}
if((start_page <= pack_page) && (end_page >= pack_page)) {
memset(&tx_buff[(pack_page - start_page) * 4], 0, 2);
}
}
}
@@ -175,16 +212,24 @@ uint16_t mf_ul_prepare_emulation_response(uint8_t* buff_rx, uint16_t len_rx, uin
} else {
memcpy(buff_tx, &mf_ul_emulate->data.data[start_page * 4], tx_len);
}
mf_ul_protect_auth_data_on_read_command(
buff_tx, start_page, (start_page + 4), mf_ul_emulate);
}
} else if(cmd == MF_UL_FAST_READ_CMD) {
if(mf_ul_emulate->support_fast_read) {
uint8_t start_page = buff_rx[1];
uint8_t end_page = buff_rx[2];
if((start_page < page_num) &&
(end_page < page_num) && (start_page < end_page)) {
tx_len = (end_page - start_page) * 4;
(end_page < page_num) && (start_page < (end_page + 1))) {
tx_len = ((end_page + 1) - start_page) * 4;
memcpy(buff_tx, &mf_ul_emulate->data.data[start_page * 4], tx_len);
}
mf_ul_protect_auth_data_on_read_command(
buff_tx, start_page, end_page, mf_ul_emulate);
} else {
// TODO make 4-bit NAK
buff_tx[0] = 0x0;
tx_len = 1;
}
}
} else if(cmd == MF_UL_WRITE) {
uint8_t write_page = buff_rx[1];
@@ -213,6 +258,22 @@ uint16_t mf_ul_prepare_emulation_response(uint8_t* buff_rx, uint16_t len_rx, uin
buff_tx[0] = 0x0A;
tx_len = 1;
}
} else if(cmd == MF_UL_AUTH) {
if(mf_ul_emulate->type >= MfUltralightTypeNTAG213) {
if(memcmp(&buff_rx[1], mf_ul_emulate->auth_data->pwd, 4) == 0) {
buff_tx[0] = mf_ul_emulate->auth_data->pack.raw[0];
buff_tx[1] = mf_ul_emulate->auth_data->pack.raw[1];
tx_len = 2;
} else if(!mf_ul_emulate->auth_data->pack.value) {
buff_tx[0] = 0x80;
buff_tx[1] = 0x80;
tx_len = 2;
} else {
// TODO make 4-bit NAK
buff_tx[0] = 0x0;
tx_len = 1;
}
}
} else if(cmd == MF_UL_READ_SIG) {
// Check 2nd byte = 0x00 - RFU
if(buff_rx[1] == 0x00) {

9
lib/nfc_protocols/mifare_ultralight.h
View File

@@ -60,6 +60,14 @@ typedef struct {
uint8_t data[MF_UL_MAX_DUMP_SIZE];
} MifareUlData;
typedef struct {
uint8_t pwd[4];
union {
uint8_t raw[2];
uint16_t value;
} pack;
} MifareUlAuthData;
typedef struct {
MfUltralightType type;
uint8_t pages_to_read;
@@ -67,6 +75,7 @@ typedef struct {
bool support_fast_read;
bool data_changed;
MifareUlData data;
MifareUlAuthData* auth_data;
} MifareUlDevice;
bool mf_ul_check_card_type(uint8_t ATQA0, uint8_t ATQA1, uint8_t SAK);