[proxmark3-svn] / client / mifare4.c

//-----------------------------------------------------------------------------
// Copyright (C) 2018 Merlok
// Copyright (C) 2018 drHatson
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// iso14443-4 mifare commands
//-----------------------------------------------------------------------------

#include "mifare4.h"
#include <ctype.h>
#include <string.h>
#include "cmdhf14a.h"
#include "util.h"
#include "ui.h"
#include "crypto/libpcrypto.h"

AccessConditions_t MFAccessConditions[] = {
	{0x00, "read AB; write AB; increment AB; decrement transfer restore AB"},
	{0x01, "read AB; decrement transfer restore AB"},
	{0x02, "read AB"},
	{0x03, "read B; write B"},
	{0x04, "read AB; writeB"},
	{0x05, "read B"},
	{0x06, "read AB; write B; increment B; decrement transfer restore AB"},
	{0x07, "none"}
};

AccessConditions_t MFAccessConditionsTrailer[] = {
	{0x00, "read A by A; read ACCESS by A; read B by A; write B by A"},
	{0x01, "write A by A; read ACCESS by A write ACCESS by A; read B by A; write B by A"},
	{0x02, "read ACCESS by A; read B by A"},
	{0x03, "write A by B; read ACCESS by AB; write ACCESS by B; write B by B"},
	{0x04, "write A by B; read ACCESS by AB; write B by B"},
	{0x05, "read ACCESS by AB; write ACCESS by B"},
	{0x06, "read ACCESS by AB"},
	{0x07, "read ACCESS by AB"}
};

char *mfGetAccessConditionsDesc(uint8_t blockn, uint8_t *data) {
	static char StaticNone[] = "none";
	
	uint8_t data1 = ((data[1] >> 4) & 0x0f) >> blockn;
	uint8_t data2 = ((data[2]) & 0x0f) >> blockn;
	uint8_t data3 = ((data[2] >> 4) & 0x0f) >> blockn;
	
	uint8_t cond = (data1 & 0x01) << 2 | (data2 & 0x01) << 1 | (data3 & 0x01);

	if (blockn == 3) {
		for (int i = 0; i < ARRAYLEN(MFAccessConditionsTrailer); i++)
			if (MFAccessConditionsTrailer[i].cond == cond) {
				return MFAccessConditionsTrailer[i].description;
			}
	} else {
		for (int i = 0; i < ARRAYLEN(MFAccessConditions); i++)
			if (MFAccessConditions[i].cond == cond) {
				return MFAccessConditions[i].description;
			}
	};
	
	return StaticNone;
};

int CalculateEncIVCommand(mf4Session *session, uint8_t *iv, bool verbose) {
	memcpy(&iv[0], session->TI, 4);
	memcpy(&iv[4], &session->R_Ctr, 2);
	memcpy(&iv[6], &session->W_Ctr, 2);
	memcpy(&iv[8], &session->R_Ctr, 2);
	memcpy(&iv[10], &session->W_Ctr, 2);
	memcpy(&iv[12], &session->R_Ctr, 2);
	memcpy(&iv[14], &session->W_Ctr, 2);

	return 0;
}

int CalculateEncIVResponse(mf4Session *session, uint8_t *iv, bool verbose) {
	memcpy(&iv[0], &session->R_Ctr, 2);
	memcpy(&iv[2], &session->W_Ctr, 2);
	memcpy(&iv[4], &session->R_Ctr, 2);
	memcpy(&iv[6], &session->W_Ctr, 2);
	memcpy(&iv[8], &session->R_Ctr, 2);
	memcpy(&iv[10], &session->W_Ctr, 2);
	memcpy(&iv[12], session->TI, 4);

	return 0;
}


int CalculateMAC(mf4Session *session, MACType_t mtype, uint8_t blockNum, uint8_t blockCount, uint8_t *data, int datalen, uint8_t *mac, bool verbose) {
	if (!session || !session->Authenticated || !mac || !data || !datalen || datalen < 1)
		return 1;
	
	memset(mac, 0x00, 8);

	uint16_t ctr = session->R_Ctr;
	switch(mtype) {
	case mtypWriteCmd:
	case mtypWriteResp:
		ctr = session->W_Ctr;
		break;
	case mtypReadCmd:
	case mtypReadResp:
		break;
	}

	uint8_t macdata[2049] = {data[0], (ctr & 0xFF), (ctr >> 8), 0};
	int macdatalen = datalen;
	memcpy(&macdata[3], session->TI, 4);

	switch(mtype) {
	case mtypReadCmd:
		memcpy(&macdata[7], &data[1], datalen - 1);
		macdatalen = datalen + 6;
		break;
	case mtypReadResp:
		macdata[7] = blockNum;
		macdata[8] = 0;
		macdata[9] = blockCount;
		memcpy(&macdata[10], &data[1], datalen - 1);
		macdatalen = datalen + 9;
		break;
	case mtypWriteCmd:
		memcpy(&macdata[7], &data[1], datalen - 1);
		macdatalen = datalen + 6;
		break;
	case mtypWriteResp:
		macdatalen = 1 + 6;
		break;
	}
	
	if (verbose)
		PrintAndLog("MAC data[%d]: %s", macdatalen, sprint_hex(macdata, macdatalen));
	
	return aes_cmac8(NULL, session->Kmac, macdata, mac, macdatalen);
}

int MifareAuth4(mf4Session *session, uint8_t *keyn, uint8_t *key, bool activateField, bool leaveSignalON, bool verbose) {
	uint8_t data[257] = {0};
	int datalen = 0;
	
	uint8_t RndA[17] = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x00};
	uint8_t RndB[17] = {0};
	
	if (session)
		session->Authenticated = false;	
	
	uint8_t cmd1[] = {0x70, keyn[1], keyn[0], 0x00};
	int res = ExchangeRAW14a(cmd1, sizeof(cmd1), activateField, true, data, sizeof(data), &datalen);
	if (res) {
		PrintAndLog("ERROR exchande raw error: %d", res);
		DropField();
		return 2;
	}
	
	if (verbose)
		PrintAndLog("<phase1: %s", sprint_hex(data, datalen));
		
	if (datalen < 1) {
		PrintAndLog("ERROR: card response length: %d", datalen);
		DropField();
		return 3;
	}
	
	if (data[0] != 0x90) {
		PrintAndLog("ERROR: card response error: %02x", data[2]);
		DropField();
		return 3;
	}

	if (datalen != 19) { // code 1b + 16b + crc 2b
		PrintAndLog("ERROR: card response must be 19 bytes long instead of: %d", datalen);
		DropField();
		return 3;
	}
	
    aes_decode(NULL, key, &data[1], RndB, 16);
	RndB[16] = RndB[0];
	if (verbose)
		PrintAndLog("RndB: %s", sprint_hex(RndB, 16));

	uint8_t cmd2[33] = {0};
	cmd2[0] = 0x72;

	uint8_t raw[32] = {0};
	memmove(raw, RndA, 16);
	memmove(&raw[16], &RndB[1], 16);

	aes_encode(NULL, key, raw, &cmd2[1], 32);
	if (verbose)
		PrintAndLog(">phase2: %s", sprint_hex(cmd2, 33));
	
	res = ExchangeRAW14a(cmd2, sizeof(cmd2), false, true, data, sizeof(data), &datalen);
	if (res) {
		PrintAndLog("ERROR exchande raw error: %d", res);
		DropField();
		return 4;
	}
	
	if (verbose)
		PrintAndLog("<phase2: %s", sprint_hex(data, datalen));

	aes_decode(NULL, key, &data[1], raw, 32);
	
	if (verbose) {
		PrintAndLog("res: %s", sprint_hex(raw, 32));
		PrintAndLog("RndA`: %s", sprint_hex(&raw[4], 16));
	}

	if (memcmp(&raw[4], &RndA[1], 16)) {
		PrintAndLog("\nERROR: Authentication FAILED. rnd not equal");
		if (verbose) {
			PrintAndLog("RndA reader: %s", sprint_hex(&RndA[1], 16));
			PrintAndLog("RndA   card: %s", sprint_hex(&raw[4], 16));
		}
		DropField();
		return 5;
	}

	if (verbose) {
		PrintAndLog(" TI: %s", sprint_hex(raw, 4));
		PrintAndLog("pic: %s", sprint_hex(&raw[20], 6));
		PrintAndLog("pcd: %s", sprint_hex(&raw[26], 6));
	}
	
	uint8_t kenc[16] = {0};
	memcpy(&kenc[0], &RndA[11], 5);
	memcpy(&kenc[5], &RndB[11], 5);
	for(int i = 0; i < 5; i++)
		kenc[10 + i] = RndA[4 + i] ^ RndB[4 + i];
	kenc[15] = 0x11;
	
	aes_encode(NULL, key, kenc, kenc, 16);
	if (verbose) {
		PrintAndLog("kenc: %s", sprint_hex(kenc, 16));
	}
	
	uint8_t kmac[16] = {0};
	memcpy(&kmac[0], &RndA[7], 5);
	memcpy(&kmac[5], &RndB[7], 5);
	for(int i = 0; i < 5; i++)
		kmac[10 + i] = RndA[0 + i] ^ RndB[0 + i];
	kmac[15] = 0x22;
	
	aes_encode(NULL, key, kmac, kmac, 16);
	if (verbose) {
		PrintAndLog("kmac: %s", sprint_hex(kmac, 16));
	}	
	
	if (!leaveSignalON)
		DropField();

	if (verbose)
		PrintAndLog("");

	if (session) {
		session->Authenticated = true;
		session->R_Ctr = 0;
		session->W_Ctr = 0;
		session->KeyNum = keyn[1] + (keyn[0] << 8);
		memmove(session->RndA, RndA, 16);
		memmove(session->RndB, RndB, 16);
		memmove(session->Key, key, 16);
		memmove(session->TI, raw, 4);
		memmove(session->PICCap2, &raw[20], 6);
		memmove(session->PCDCap2, &raw[26], 6);
		memmove(session->Kenc, kenc, 16);
		memmove(session->Kmac, kmac, 16);
	}
	
	PrintAndLog("Authentication OK");
	
	return 0;
}

// Mifare Memory Structure: up to 32 Sectors with 4 blocks each (1k and 2k cards),
// plus evtl. 8 sectors with 16 blocks each (4k cards)
uint8_t mfNumBlocksPerSector(uint8_t sectorNo) {
	if (sectorNo < 32) 
		return 4;
	else
		return 16;
}

uint8_t mfFirstBlockOfSector(uint8_t sectorNo) {
	if (sectorNo < 32)
		return sectorNo * 4;
	else
		return 32 * 4 + (sectorNo - 32) * 16;
}

uint8_t mfSectorTrailer(uint8_t blockNo) {
	if (blockNo < 32*4) {
		return (blockNo | 0x03);
	} else {
		return (blockNo | 0x0f);
	}
}

bool mfIsSectorTrailer(uint8_t blockNo) {
	return (blockNo == mfSectorTrailer(blockNo));
}

uint8_t mfSectorNum(uint8_t blockNo) {
	if (blockNo < 32 * 4)
		return blockNo / 4;
	else
		return 32 + (blockNo - 32 * 4) / 16;
		
}
Commit	Line	Data
ae3340a0 OM	1	//-----------------------------------------------------------------------------
ae3340a0 OM	2	// Copyright (C) 2018 Merlok
4b5d696c	3	// Copyright (C) 2018 drHatson
ae3340a0 OM	4	//
	5	// This code is licensed to you under the terms of the GNU GPL, version 2 or,
	6	// at your option, any later version. See the LICENSE.txt file for the text of
	7	// the license.
	8	//-----------------------------------------------------------------------------
	9	// iso14443-4 mifare commands
	10	//-----------------------------------------------------------------------------
	11
	12	#include "mifare4.h"
	13	#include <ctype.h>
	14	#include <string.h>
	15	#include "cmdhf14a.h"
	16	#include "util.h"
	17	#include "ui.h"
700d8687	18	#include "crypto/libpcrypto.h"
ae3340a0	19
ac4ecfe3 OM	20	AccessConditions_t MFAccessConditions[] = {
	21	{0x00, "read AB; write AB; increment AB; decrement transfer restore AB"},
	22	{0x01, "read AB; decrement transfer restore AB"},
	23	{0x02, "read AB"},
	24	{0x03, "read B; write B"},
	25	{0x04, "read AB; writeB"},
	26	{0x05, "read B"},
	27	{0x06, "read AB; write B; increment B; decrement transfer restore AB"},
	28	{0x07, "none"}
	29	};
	30
	31	AccessConditions_t MFAccessConditionsTrailer[] = {
	32	{0x00, "read A by A; read ACCESS by A; read B by A; write B by A"},
	33	{0x01, "write A by A; read ACCESS by A write ACCESS by A; read B by A; write B by A"},
	34	{0x02, "read ACCESS by A; read B by A"},
	35	{0x03, "write A by B; read ACCESS by AB; write ACCESS by B; write B by B"},
	36	{0x04, "write A by B; read ACCESS by AB; write B by B"},
	37	{0x05, "read ACCESS by AB; write ACCESS by B"},
	38	{0x06, "read ACCESS by AB"},
	39	{0x07, "read ACCESS by AB"}
	40	};
	41
	42	char mfGetAccessConditionsDesc(uint8_t blockn, uint8_t data) {
	43	static char StaticNone[] = "none";
	44
	45	uint8_t data1 = ((data[1] >> 4) & 0x0f) >> blockn;
	46	uint8_t data2 = ((data[2]) & 0x0f) >> blockn;
	47	uint8_t data3 = ((data[2] >> 4) & 0x0f) >> blockn;
	48
	49	uint8_t cond = (data1 & 0x01) << 2 \| (data2 & 0x01) << 1 \| (data3 & 0x01);
	50
	51	if (blockn == 3) {
	52	for (int i = 0; i < ARRAYLEN(MFAccessConditionsTrailer); i++)
	53	if (MFAccessConditionsTrailer[i].cond == cond) {
	54	return MFAccessConditionsTrailer[i].description;
	55	}
	56	} else {
	57	for (int i = 0; i < ARRAYLEN(MFAccessConditions); i++)
	58	if (MFAccessConditions[i].cond == cond) {
	59	return MFAccessConditions[i].description;
	60	}
	61	};
	62
	63	return StaticNone;
	64	};
	65
4b5d696c	66	int CalculateEncIVCommand(mf4Session session, uint8_t iv, bool verbose) {
	67	memcpy(&iv[0], session->TI, 4);
	68	memcpy(&iv[4], &session->R_Ctr, 2);
	69	memcpy(&iv[6], &session->W_Ctr, 2);
	70	memcpy(&iv[8], &session->R_Ctr, 2);
	71	memcpy(&iv[10], &session->W_Ctr, 2);
	72	memcpy(&iv[12], &session->R_Ctr, 2);
	73	memcpy(&iv[14], &session->W_Ctr, 2);
	74
	75	return 0;
	76	}
	77
	78	int CalculateEncIVResponse(mf4Session session, uint8_t iv, bool verbose) {
	79	memcpy(&iv[0], &session->R_Ctr, 2);
	80	memcpy(&iv[2], &session->W_Ctr, 2);
	81	memcpy(&iv[4], &session->R_Ctr, 2);
	82	memcpy(&iv[6], &session->W_Ctr, 2);
	83	memcpy(&iv[8], &session->R_Ctr, 2);
	84	memcpy(&iv[10], &session->W_Ctr, 2);
	85	memcpy(&iv[12], session->TI, 4);
	86
	87	return 0;
	88	}
	89
	90
	91	int CalculateMAC(mf4Session session, MACType_t mtype, uint8_t blockNum, uint8_t blockCount, uint8_t data, int datalen, uint8_t *mac, bool verbose) {
	92	if (!session \|\| !session->Authenticated \|\| !mac \|\| !data \|\| !datalen \|\| datalen < 1)
c8a0f550 OM	93	return 1;
	94
	95	memset(mac, 0x00, 8);
4b5d696c	96
	97	uint16_t ctr = session->R_Ctr;
	98	switch(mtype) {
	99	case mtypWriteCmd:
	100	case mtypWriteResp:
	101	ctr = session->W_Ctr;
	102	break;
	103	case mtypReadCmd:
	104	case mtypReadResp:
	105	break;
	106	}
	107
	108	uint8_t macdata[2049] = {data[0], (ctr & 0xFF), (ctr >> 8), 0};
	109	int macdatalen = datalen;
	110	memcpy(&macdata[3], session->TI, 4);
	111
	112	switch(mtype) {
	113	case mtypReadCmd:
	114	memcpy(&macdata[7], &data[1], datalen - 1);
	115	macdatalen = datalen + 6;
	116	break;
	117	case mtypReadResp:
	118	macdata[7] = blockNum;
	119	macdata[8] = 0;
	120	macdata[9] = blockCount;
	121	memcpy(&macdata[10], &data[1], datalen - 1);
	122	macdatalen = datalen + 9;
	123	break;
	124	case mtypWriteCmd:
	125	memcpy(&macdata[7], &data[1], datalen - 1);
	126	macdatalen = datalen + 6;
	127	break;
	128	case mtypWriteResp:
	129	macdatalen = 1 + 6;
	130	break;
	131	}
c8a0f550 OM	132
c8a0f550 OM	133	if (verbose)
4b5d696c	134	PrintAndLog("MAC data[%d]: %s", macdatalen, sprint_hex(macdata, macdatalen));
c8a0f550	135
4b5d696c	136	return aes_cmac8(NULL, session->Kmac, macdata, mac, macdatalen);
c8a0f550 OM	137	}
c8a0f550 OM	138
ae3340a0 OM	139	int MifareAuth4(mf4Session session, uint8_t keyn, uint8_t *key, bool activateField, bool leaveSignalON, bool verbose) {
	140	uint8_t data[257] = {0};
	141	int datalen = 0;
	142
4b5d696c	143	uint8_t RndA[17] = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x00};
4b5d696c	144	uint8_t RndB[17] = {0};
ae3340a0 OM	145
	146	if (session)
	147	session->Authenticated = false;
	148
	149	uint8_t cmd1[] = {0x70, keyn[1], keyn[0], 0x00};
	150	int res = ExchangeRAW14a(cmd1, sizeof(cmd1), activateField, true, data, sizeof(data), &datalen);
	151	if (res) {
	152	PrintAndLog("ERROR exchande raw error: %d", res);
	153	DropField();
	154	return 2;
	155	}
	156
	157	if (verbose)
	158	PrintAndLog("<phase1: %s", sprint_hex(data, datalen));
	159
	160	if (datalen < 1) {
	161	PrintAndLog("ERROR: card response length: %d", datalen);
	162	DropField();
	163	return 3;
	164	}
	165
	166	if (data[0] != 0x90) {
	167	PrintAndLog("ERROR: card response error: %02x", data[2]);
	168	DropField();
	169	return 3;
	170	}
	171
	172	if (datalen != 19) { // code 1b + 16b + crc 2b
	173	PrintAndLog("ERROR: card response must be 19 bytes long instead of: %d", datalen);
	174	DropField();
	175	return 3;
	176	}
	177
4b5d696c	178	aes_decode(NULL, key, &data[1], RndB, 16);
4b5d696c	179	RndB[16] = RndB[0];
ae3340a0	180	if (verbose)
4b5d696c	181	PrintAndLog("RndB: %s", sprint_hex(RndB, 16));
ae3340a0 OM	182
	183	uint8_t cmd2[33] = {0};
	184	cmd2[0] = 0x72;
	185
	186	uint8_t raw[32] = {0};
4b5d696c	187	memmove(raw, RndA, 16);
4b5d696c	188	memmove(&raw[16], &RndB[1], 16);
ae3340a0 OM	189
	190	aes_encode(NULL, key, raw, &cmd2[1], 32);
	191	if (verbose)
	192	PrintAndLog(">phase2: %s", sprint_hex(cmd2, 33));
	193
c8a0f550	194	res = ExchangeRAW14a(cmd2, sizeof(cmd2), false, true, data, sizeof(data), &datalen);
ae3340a0 OM	195	if (res) {
	196	PrintAndLog("ERROR exchande raw error: %d", res);
	197	DropField();
	198	return 4;
	199	}
	200
	201	if (verbose)
	202	PrintAndLog("<phase2: %s", sprint_hex(data, datalen));
	203
	204	aes_decode(NULL, key, &data[1], raw, 32);
	205
	206	if (verbose) {
	207	PrintAndLog("res: %s", sprint_hex(raw, 32));
4b5d696c	208	PrintAndLog("RndA`: %s", sprint_hex(&raw[4], 16));
ae3340a0 OM	209	}
ae3340a0 OM	210
4b5d696c	211	if (memcmp(&raw[4], &RndA[1], 16)) {
ae3340a0 OM	212	PrintAndLog("\nERROR: Authentication FAILED. rnd not equal");
ae3340a0 OM	213	if (verbose) {
4b5d696c	214	PrintAndLog("RndA reader: %s", sprint_hex(&RndA[1], 16));
4b5d696c	215	PrintAndLog("RndA card: %s", sprint_hex(&raw[4], 16));
ae3340a0 OM	216	}
	217	DropField();
	218	return 5;
	219	}
	220
4b5d696c	221	if (verbose) {
	222	PrintAndLog(" TI: %s", sprint_hex(raw, 4));
	223	PrintAndLog("pic: %s", sprint_hex(&raw[20], 6));
	224	PrintAndLog("pcd: %s", sprint_hex(&raw[26], 6));
	225	}
	226
	227	uint8_t kenc[16] = {0};
	228	memcpy(&kenc[0], &RndA[11], 5);
	229	memcpy(&kenc[5], &RndB[11], 5);
	230	for(int i = 0; i < 5; i++)
	231	kenc[10 + i] = RndA[4 + i] ^ RndB[4 + i];
	232	kenc[15] = 0x11;
	233
	234	aes_encode(NULL, key, kenc, kenc, 16);
	235	if (verbose) {
	236	PrintAndLog("kenc: %s", sprint_hex(kenc, 16));
	237	}
	238
	239	uint8_t kmac[16] = {0};
	240	memcpy(&kmac[0], &RndA[7], 5);
	241	memcpy(&kmac[5], &RndB[7], 5);
	242	for(int i = 0; i < 5; i++)
	243	kmac[10 + i] = RndA[0 + i] ^ RndB[0 + i];
	244	kmac[15] = 0x22;
	245
	246	aes_encode(NULL, key, kmac, kmac, 16);
	247	if (verbose) {
	248	PrintAndLog("kmac: %s", sprint_hex(kmac, 16));
	249	}
	250
ae3340a0 OM	251	if (!leaveSignalON)
	252	DropField();
	253
	254	if (verbose)
	255	PrintAndLog("");
	256
	257	if (session) {
	258	session->Authenticated = true;
4b5d696c	259	session->R_Ctr = 0;
4b5d696c	260	session->W_Ctr = 0;
ae3340a0	261	session->KeyNum = keyn[1] + (keyn[0] << 8);
4b5d696c	262	memmove(session->RndA, RndA, 16);
4b5d696c	263	memmove(session->RndB, RndB, 16);
c8a0f550	264	memmove(session->Key, key, 16);
4b5d696c	265	memmove(session->TI, raw, 4);
	266	memmove(session->PICCap2, &raw[20], 6);
	267	memmove(session->PCDCap2, &raw[26], 6);
	268	memmove(session->Kenc, kenc, 16);
	269	memmove(session->Kmac, kmac, 16);
ae3340a0 OM	270	}
	271
	272	PrintAndLog("Authentication OK");
	273
	274	return 0;
	275	}
	276
c8a0f550 OM	277	// Mifare Memory Structure: up to 32 Sectors with 4 blocks each (1k and 2k cards),
	278	// plus evtl. 8 sectors with 16 blocks each (4k cards)
	279	uint8_t mfNumBlocksPerSector(uint8_t sectorNo) {
	280	if (sectorNo < 32)
	281	return 4;
	282	else
	283	return 16;
	284	}
	285
	286	uint8_t mfFirstBlockOfSector(uint8_t sectorNo) {
	287	if (sectorNo < 32)
	288	return sectorNo * 4;
	289	else
	290	return 32 * 4 + (sectorNo - 32) * 16;
	291	}
	292
	293	uint8_t mfSectorTrailer(uint8_t blockNo) {
	294	if (blockNo < 32*4) {
	295	return (blockNo \| 0x03);
	296	} else {
	297	return (blockNo \| 0x0f);
	298	}
	299	}
	300
	301	bool mfIsSectorTrailer(uint8_t blockNo) {
	302	return (blockNo == mfSectorTrailer(blockNo));
	303	}
	304
	305	uint8_t mfSectorNum(uint8_t blockNo) {
	306	if (blockNo < 32 * 4)
	307	return blockNo / 4;
	308	else
	309	return 32 + (blockNo - 32 * 4) / 16;
	310
	311	}