libfreefare/examples/mifare-classic-write-ndef.c
2017-06-29 12:25:53 +02:00

417 lines
12 KiB
C

#if defined(HAVE_CONFIG_H)
#include "config.h"
#endif
#include <err.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <nfc/nfc.h>
#include <freefare.h>
#define MIN(a,b) ((a < b) ? a: b)
MifareClassicKey default_keys[] = {
{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
{ 0xd3, 0xf7, 0xd3, 0xf7, 0xd3, 0xf7 },
{ 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5 },
{ 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5 },
{ 0x4d, 0x3a, 0x99, 0xc3, 0x51, 0xdd },
{ 0x1a, 0x98, 0x2c, 0x7e, 0x45, 0x9a },
{ 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff },
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
};
struct mifare_classic_key_and_type {
MifareClassicKey key;
MifareClassicKeyType type;
};
struct {
bool interactive;
} write_options = {
.interactive = true
};
const MifareClassicKey default_keyb = {
0xd3, 0xf7, 0xd3, 0xf7, 0xd3, 0xf7
};
const uint8_t ndef_default_msg[33] = {
0xd1, 0x02, 0x1c, 0x53, 0x70, 0x91, 0x01, 0x09,
0x54, 0x02, 0x65, 0x6e, 0x4c, 0x69, 0x62, 0x6e,
0x66, 0x63, 0x51, 0x01, 0x0b, 0x55, 0x03, 0x6c,
0x69, 0x62, 0x6e, 0x66, 0x63, 0x2e, 0x6f, 0x72,
0x67
};
uint8_t *ndef_msg;
size_t ndef_msg_len;
static int
search_sector_key(FreefareTag tag, MifareClassicSectorNumber sector, MifareClassicKey *key, MifareClassicKeyType *key_type)
{
MifareClassicBlockNumber block = mifare_classic_sector_last_block(sector);
/*
* FIXME: We should not assume that if we have full access to trailer block
* we also have a full access to data blocks.
*/
mifare_classic_disconnect(tag);
for (size_t i = 0; i < (sizeof(default_keys) / sizeof(MifareClassicKey)); i++) {
if ((0 == mifare_classic_connect(tag)) && (0 == mifare_classic_authenticate(tag, block, default_keys[i], MFC_KEY_A))) {
if ((1 == mifare_classic_get_trailer_block_permission(tag, block, MCAB_WRITE_KEYA, MFC_KEY_A)) &&
(1 == mifare_classic_get_trailer_block_permission(tag, block, MCAB_WRITE_ACCESS_BITS, MFC_KEY_A)) &&
(1 == mifare_classic_get_trailer_block_permission(tag, block, MCAB_WRITE_KEYB, MFC_KEY_A))) {
memcpy(key, &default_keys[i], sizeof(MifareClassicKey));
*key_type = MFC_KEY_A;
return 1;
}
}
mifare_classic_disconnect(tag);
if ((0 == mifare_classic_connect(tag)) && (0 == mifare_classic_authenticate(tag, block, default_keys[i], MFC_KEY_B))) {
if ((1 == mifare_classic_get_trailer_block_permission(tag, block, MCAB_WRITE_KEYA, MFC_KEY_B)) &&
(1 == mifare_classic_get_trailer_block_permission(tag, block, MCAB_WRITE_ACCESS_BITS, MFC_KEY_B)) &&
(1 == mifare_classic_get_trailer_block_permission(tag, block, MCAB_WRITE_KEYB, MFC_KEY_B))) {
memcpy(key, &default_keys[i], sizeof(MifareClassicKey));
*key_type = MFC_KEY_B;
return 1;
}
}
mifare_classic_disconnect(tag);
}
warnx("No known authentication key for sector 0x%02x\n", sector);
return 0;
}
static int
fix_mad_trailer_block(nfc_device *device, FreefareTag tag, MifareClassicSectorNumber sector, MifareClassicKey key, MifareClassicKeyType key_type)
{
MifareClassicBlock block;
mifare_classic_trailer_block(&block, mad_public_key_a, 0x0, 0x1, 0x1, 0x6, 0x00, default_keyb);
if (mifare_classic_authenticate(tag, mifare_classic_sector_last_block(sector), key, key_type) < 0) {
nfc_perror(device, "fix_mad_trailer_block mifare_classic_authenticate");
return -1;
}
if (mifare_classic_write(tag, mifare_classic_sector_last_block(sector), block) < 0) {
nfc_perror(device, "mifare_classic_write");
return -1;
}
return 0;
}
static void
usage(char *progname)
{
fprintf(stderr, "usage: %s -i FILE\n", progname);
fprintf(stderr, "\nOptions:\n");
fprintf(stderr, " -y Do not ask for confirmation\n");
fprintf(stderr, " -i Use FILE as NDEF message to write on card (\"-\" = stdin)\n");
}
int
main(int argc, char *argv[])
{
int error = 0;
nfc_device *device = NULL;
FreefareTag *tags = NULL;
Mad mad;
MifareClassicKey transport_key = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
int ch;
char *ndef_input = NULL;
while ((ch = getopt(argc, argv, "hyi:")) != -1) {
switch (ch) {
case 'h':
usage(argv[0]);
exit(EXIT_SUCCESS);
break;
case 'y':
write_options.interactive = false;
break;
case 'i':
ndef_input = optarg;
break;
case '?':
if (optopt == 'i')
fprintf(stderr, "Option -%c requires an argument.\n", optopt);
/* FALLTHROUGH */
default:
usage(argv[0]);
exit(EXIT_FAILURE);
}
}
if (ndef_input == NULL) {
ndef_msg = (uint8_t *)ndef_default_msg;
ndef_msg_len = sizeof(ndef_default_msg);
} else {
FILE *ndef_stream = NULL;
if ((strlen(ndef_input) == 1) && (ndef_input[0] == '-')) {
// FIXME stdin as input have to be readed and buffered in ndef_msg
ndef_stream = stdin;
fprintf(stderr, "stdin as NDEF is not implemented");
exit(EXIT_FAILURE);
} else {
ndef_stream = fopen(ndef_input, "rb");
if (!ndef_stream) {
fprintf(stderr, "Could not open file %s.\n", ndef_input);
exit(EXIT_FAILURE);
}
fseek(ndef_stream, 0L, SEEK_END);
ndef_msg_len = ftell(ndef_stream);
fseek(ndef_stream, 0L, SEEK_SET);
if (!(ndef_msg = malloc(ndef_msg_len))) {
err(EXIT_FAILURE, "malloc");
}
if (fread(ndef_msg, 1, ndef_msg_len, ndef_stream) != ndef_msg_len) {
fprintf(stderr, "Could not read NDEF from file: %s\n", ndef_input);
fclose(ndef_stream);
free(ndef_msg);
exit(EXIT_FAILURE);
}
fclose(ndef_stream);
}
}
printf("NDEF file is %zu bytes long.\n", ndef_msg_len);
struct mifare_classic_key_and_type *card_write_keys;
if (!(card_write_keys = malloc(40 * sizeof(*card_write_keys)))) {
err(EXIT_FAILURE, "malloc");
}
nfc_connstring devices[8];
size_t device_count;
nfc_context *context;
nfc_init(&context);
if (context == NULL)
errx(EXIT_FAILURE, "Unable to init libnfc (malloc)");
device_count = nfc_list_devices(context, devices, 8);
if (device_count <= 0)
errx(EXIT_FAILURE, "No NFC device found.");
for (size_t d = 0; d < device_count; d++) {
device = nfc_open(context, devices[d]);
if (!device) {
warnx("nfc_open() failed.");
error = EXIT_FAILURE;
continue;
}
tags = freefare_get_tags(device);
if (!tags) {
nfc_close(device);
errx(EXIT_FAILURE, "Error listing MIFARE classic tag.");
}
for (int i = 0; (!error) && tags[i]; i++) {
switch (freefare_get_tag_type(tags[i])) {
case MIFARE_CLASSIC_1K:
case MIFARE_CLASSIC_4K:
break;
default:
continue;
}
char *tag_uid = freefare_get_tag_uid(tags[i]);
char buffer[BUFSIZ];
printf("Found %s with UID %s. ", freefare_get_tag_friendly_name(tags[i]), tag_uid);
bool write_ndef = true;
if (write_options.interactive) {
printf("Write NDEF [yN] ");
fgets(buffer, BUFSIZ, stdin);
write_ndef = ((buffer[0] == 'y') || (buffer[0] == 'Y'));
} else {
printf("\n");
}
for (int n = 0; n < 40; n++) {
memcpy(card_write_keys[n].key, transport_key, sizeof(transport_key));
card_write_keys[n].type = MFC_KEY_A;
}
if (write_ndef) {
switch (freefare_get_tag_type(tags[i])) {
case MIFARE_CLASSIC_4K:
if (!search_sector_key(tags[i], 0x10, &(card_write_keys[0x10].key), &(card_write_keys[0x10].type))) {
error = 1;
goto error;
}
/* fallthrough */
case MIFARE_CLASSIC_1K:
if (!search_sector_key(tags[i], 0x00, &(card_write_keys[0x00].key), &(card_write_keys[0x00].type))) {
error = 1;
goto error;
}
break;
default:
/* Keep compiler quiet */
break;
}
if (!error) {
/* Ensure the auth key is always a B one. If not, change it! */
switch (freefare_get_tag_type(tags[i])) {
case MIFARE_CLASSIC_4K:
if (card_write_keys[0x10].type != MFC_KEY_B) {
if (0 != fix_mad_trailer_block(device, tags[i], 0x10, card_write_keys[0x10].key, card_write_keys[0x10].type)) {
error = 1;
goto error;
}
memcpy(&(card_write_keys[0x10].key), &default_keyb, sizeof(MifareClassicKey));
card_write_keys[0x10].type = MFC_KEY_B;
}
/* fallthrough */
case MIFARE_CLASSIC_1K:
if (card_write_keys[0x00].type != MFC_KEY_B) {
if (0 != fix_mad_trailer_block(device, tags[i], 0x00, card_write_keys[0x00].key, card_write_keys[0x00].type)) {
error = 1;
goto error;
}
memcpy(&(card_write_keys[0x00].key), &default_keyb, sizeof(MifareClassicKey));
card_write_keys[0x00].type = MFC_KEY_B;
}
break;
default:
/* Keep compiler quiet */
break;
}
}
size_t encoded_size;
uint8_t *tlv_data = tlv_encode(3, ndef_msg, ndef_msg_len, &encoded_size);
/*
* At his point, we should have collected all information needed to
* succeed.
*/
// If the card already has a MAD, load it.
if ((mad = mad_read(tags[i]))) {
// If our application already exists, erase it.
MifareClassicSectorNumber *sectors, *p;
sectors = p = mifare_application_find(mad, mad_nfcforum_aid);
if (sectors) {
while (*p) {
if (mifare_classic_authenticate(tags[i], mifare_classic_sector_last_block(*p), default_keyb, MFC_KEY_B) < 0) {
nfc_perror(device, "mifare_classic_authenticate");
error = 1;
goto error;
}
if (mifare_classic_format_sector(tags[i], *p) < 0) {
nfc_perror(device, "mifare_classic_format_sector");
error = 1;
goto error;
}
p++;
}
}
free(sectors);
mifare_application_free(mad, mad_nfcforum_aid);
} else {
// Create a MAD and mark unaccessible sectors in the card
if (!(mad = mad_new((freefare_get_tag_type(tags[i]) == MIFARE_CLASSIC_4K) ? 2 : 1))) {
perror("mad_new");
error = 1;
goto error;
}
MifareClassicSectorNumber max_s = 0;
switch (freefare_get_tag_type(tags[i])) {
case MIFARE_CLASSIC_1K:
max_s = 15;
break;
case MIFARE_CLASSIC_4K:
max_s = 39;
break;
default:
/* Keep compiler quiet */
break;
}
// Mark unusable sectors as so
for (size_t s = max_s; s; s--) {
if (s == 0x10) continue;
if (!search_sector_key(tags[i], s, &(card_write_keys[s].key), &(card_write_keys[s].type))) {
mad_set_aid(mad, s, mad_defect_aid);
} else if ((memcmp(card_write_keys[s].key, transport_key, sizeof(transport_key)) != 0) &&
(card_write_keys[s].type != MFC_KEY_A)) {
// Revert to transport configuration
if (mifare_classic_format_sector(tags[i], s) < 0) {
nfc_perror(device, "mifare_classic_format_sector");
error = 1;
goto error;
}
}
}
}
MifareClassicSectorNumber *sectors = mifare_application_alloc(mad, mad_nfcforum_aid, encoded_size);
if (!sectors) {
nfc_perror(device, "mifare_application_alloc");
error = EXIT_FAILURE;
goto error;
}
if (mad_write(tags[i], mad, card_write_keys[0x00].key, card_write_keys[0x10].key) < 0) {
nfc_perror(device, "mad_write");
error = EXIT_FAILURE;
goto error;
}
int s = 0;
while (sectors[s]) {
MifareClassicBlockNumber block = mifare_classic_sector_last_block(sectors[s]);
MifareClassicBlock block_data;
mifare_classic_trailer_block(&block_data, mifare_classic_nfcforum_public_key_a, 0x0, 0x0, 0x0, 0x6, 0x40, default_keyb);
if (mifare_classic_authenticate(tags[i], block, card_write_keys[sectors[s]].key, card_write_keys[sectors[s]].type) < 0) {
nfc_perror(device, "mifare_classic_authenticate");
error = EXIT_FAILURE;
goto error;
}
if (mifare_classic_write(tags[i], block, block_data) < 0) {
nfc_perror(device, "mifare_classic_write");
error = EXIT_FAILURE;
goto error;
}
s++;
}
if ((ssize_t) encoded_size != mifare_application_write(tags[i], mad, mad_nfcforum_aid, tlv_data, encoded_size, default_keyb, MCAB_WRITE_KEYB)) {
nfc_perror(device, "mifare_application_write");
error = EXIT_FAILURE;
goto error;
}
free(sectors);
free(tlv_data);
free(mad);
}
error:
free(tag_uid);
}
if (ndef_msg != ndef_default_msg)
free(ndef_msg);
freefare_free_tags(tags);
nfc_close(device);
}
free(card_write_keys);
nfc_exit(context);
exit(error);
}