//-----------------------------------------------------------------------------
// 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, "rdAB wrAB incAB dectrAB"},
	{0x01, "rdAB dectrAB"},
	{0x02, "rdAB"},
	{0x03, "rdB wrB"},
	{0x04, "rdAB wrB"},
	{0x05, "rdB"},
	{0x06, "rdAB wrB incB dectrAB"},
	{0x07, "none"}
};

AccessConditions_t MFAccessConditionsTrailer[] = {
	{0x00, "rdAbyA rdCbyA rdBbyA wrBbyA"},
	{0x01, "wrAbyA rdCbyA wrCbyA rdBbyA wrBbyA"},
	{0x02, "rdCbyA rdBbyA"},
	{0x03, "wrAbyB rdCbyAB wrCbyB wrBbyB"},
	{0x04, "wrAbyB rdCbyAB wrBbyB"},
	{0x05, "rdCbyAB wrCbyB"},
	{0x06, "rdCbyAB"},
	{0x07, "rdCbyAB"}
};

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) {
		PrintAndLogEx(ERR, "Exchande raw error: %d", res);
		DropField();
		return 2;
	}
	
	if (verbose)
		PrintAndLogEx(INFO, "<phase1: %s", sprint_hex(data, datalen));
		
	if (datalen < 1) {
		PrintAndLogEx(ERR, "Card response wrong length: %d", datalen);
		DropField();
		return 3;
	}
	
	if (data[0] != 0x90) {
		PrintAndLogEx(ERR, "Card response error: %02x", data[2]);
		DropField();
		return 3;
	}

	if (datalen != 19) { // code 1b + 16b + crc 2b
		PrintAndLogEx(ERR, "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)
		PrintAndLogEx(INFO, "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)
		PrintAndLogEx(INFO, ">phase2: %s", sprint_hex(cmd2, 33));
	
	res = ExchangeRAW14a(cmd2, sizeof(cmd2), false, true, data, sizeof(data), &datalen);
	if (res) {
		PrintAndLogEx(ERR, "Exchande raw error: %d", res);
		DropField();
		return 4;
	}
	
	if (verbose)
		PrintAndLogEx(INFO, "<phase2: %s", sprint_hex(data, datalen));

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

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

	if (verbose) {
		PrintAndLogEx(INFO, " TI: %s", sprint_hex(raw, 4));
		PrintAndLogEx(INFO, "pic: %s", sprint_hex(&raw[20], 6));
		PrintAndLogEx(INFO, "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) {
		PrintAndLogEx(INFO, "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) {
		PrintAndLogEx(INFO, "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);
	}
	
	PrintAndLogEx(INFO, "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;
		
}