add first version of easycard dumping tool

1 files changed, 180 insertions, 0 deletions

diff --git a/easytool/easytool.c b/easytool/easytool.c
new file mode 100644
index 0000000..5a77997
--- /dev/null
+++ b/easytool/easytool.c
@@ -0,0 +1,180 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <fcntl.h>
+#include <string.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#include <nfc/nfc-types.h>
+#include <nfc/mifaretag.h>
+
+struct value_string {
+	unsigned int value;
+	const char *str;
+};
+
+static char namebuf[255];
+const char *get_value_string(const struct value_string *vs, uint32_t val)
+{
+	int i;
+
+	for (i = 0;; i++) {
+		if (vs[i].value == 0 && vs[i].str == NULL)
+			break;
+		if (vs[i].value == val)
+			return vs[i].str;
+	}
+
+	snprintf(namebuf, sizeof(namebuf), "unknown 0x%x", val);
+	return namebuf;
+}
+
+
+struct {
+	int fd;
+	unsigned long size;
+	mifare_tag *mft;
+} global;
+
+#define ABP_C1	0x04
+#define ABP_C2	0x02
+#define ABP_C3	0x01
+
+struct acc_bits_parsed {
+	uint8_t block[4];
+};
+
+static void dump_acc_bits(const struct acc_bits_parsed *abp)
+{
+	uint8_t block;
+
+	for (block = 0; block < 4; block++) {
+		printf("\tBlock %u: %x (%u %u %u)\n", block, abp->block[block],
+			abp->block[block] & ABP_C1 ? 1 : 0,
+			abp->block[block] & ABP_C2 ? 1 : 0,
+			abp->block[block] & ABP_C3 ? 1 : 0);
+	}
+}
+
+static void parse_acc_bits(struct acc_bits_parsed *abp, uint8_t *acc_bits)
+{
+	uint8_t c1, c2, c3;
+	uint8_t block;
+
+	memset(abp, 0, sizeof(*abp));
+
+	c1 = acc_bits[1] >> 4;
+	c2 = acc_bits[2] & 0xf;
+	c3 = acc_bits[2] >> 4;
+
+	printf("C1 = %x, C2 = %x, C3 = %x\n", c1, c2, c3);
+
+	for (block = 0; block < 4; block++) {
+		uint8_t testbit = 1 << block;
+		if (c1 & testbit)
+			abp->block[block] |= ABP_C1;
+		if (c2 & testbit)
+			abp->block[block] |= ABP_C2;
+		if (c3 & testbit)
+			abp->block[block] |= ABP_C3;
+	}
+}
+
+#define EASY_TT_MRT_ENTER	0x00
+#define EASY_TT_MRT_EXIT	0x11
+#define EASY_TT_PURCHASE	0x20
+
+struct value_string easy_tt_names[] = {
+	{ EASY_TT_MRT_ENTER,	"Enter MRT Stn" },
+	{ EASY_TT_MRT_EXIT,	"Leave MRT Stn" },
+	{ EASY_TT_PURCHASE,	"Shop Purchase" },
+	{ 0,			NULL }
+};
+
+/* storage of a transaction log record on the transponder itself */
+struct easy_log_rec {
+	uint8_t unknown[2];
+	uint8_t timestamp[3];	/* seconds since January 1st 1970 / 256 */
+	uint8_t trans_type;
+	uint16_t amount;	/* transaction amount / value */
+	uint16_t remaining;	/* remaining value on card _after_ trans */
+	uint8_t unknown2[6];
+} __attribute__ ((packed));
+
+static time_t convert_timestamp(const uint8_t *easy_ts)
+{
+	return (easy_ts[2] << 16 | easy_ts[1] << 8 | easy_ts[0]) << 8;
+}
+
+static void dump_easy_log(const struct easy_log_rec *elr)
+{
+	time_t t_time = convert_timestamp(elr->timestamp);
+	struct tm *t_tm = gmtime(&t_time);
+	printf("%u-%u-%u %u:%u | %10s %u NTD -> %u NTD remaining\n",
+		t_tm->tm_year+1900, t_tm->tm_mon+1, t_tm->tm_mday,
+		t_tm->tm_hour, t_tm->tm_min, 
+		get_value_string(easy_tt_names, elr->trans_type),
+		elr->amount, elr->remaining);
+}
+
+static dump_mfcl(mifare_tag *mft)
+{
+	unsigned int sect;
+
+	mifare_block_manufacturer *manuf = &mft->amb[0].mbm;
+
+	printf("UID %x, ATQA %x\n", ntohl(*((uint32_t *) manuf->abtUID)),
+		ntohs(*((uint16_t *) manuf->abtATQA)));
+
+	for (sect = 0; sect < 16; sect++) {
+		unsigned int block_base = sect * 4;
+		uint8_t *access_bits = mft->amb[block_base+3].mbt.abtAccessBits;
+		struct acc_bits_parsed abp;
+		int i;
+
+		printf("Sector %02u (base: 0x%02x) Access bits: 0x%08x\n", sect,
+			sect*4*16, ntohl(*((uint32_t *) access_bits)));
+		//parse_acc_bits(&abp, access_bits);
+		//dump_acc_bits(&abp);
+		if (sect == 3 || sect == 4) {
+			for (i = 0; i < 3; i++) {
+				void *data = mft->amb[block_base+i].mbd.abtData;
+				dump_easy_log(data);
+			}
+		}
+	}
+}
+
+
+int main(int argc, char **argv)
+{
+	struct stat st;
+
+	global.fd = open(argv[1], O_RDONLY);
+	if (global.fd < 0) {
+		perror("open");
+		exit(1);
+	}
+	if (fstat(global.fd, &st) < 0) {
+		perror("stat");
+		exit(1);
+	}
+	global.size = st.st_size;
+	global.mft = mmap(NULL, global.size, PROT_READ, MAP_SHARED,
+			  global.fd, 0);
+	if (!global.mft) {
+		perror("mmap");
+		exit(1);
+	}
+
+	dump_mfcl(global.mft);
+
+	munmap(global.mft, global.size);
+	close(global.fd);
+	exit(0);
+}