FIX: Coverity, Unintended sign extension, data[7] would have become int, then uint64_...

[proxmark3-svn] / armsrc / mifaresniff.c

//-----------------------------------------------------------------------------\r
// Merlok - 2012\r
//\r
// This code is licensed to you under the terms of the GNU GPL, version 2 or,\r
// at your option, any later version. See the LICENSE.txt file for the text of\r
// the license.\r
//-----------------------------------------------------------------------------\r
// Routines to support mifare classic sniffer.\r
//-----------------------------------------------------------------------------\r
\r
#include "mifaresniff.h"\r
#include "apps.h"\r
\r
static int sniffState = SNF_INIT;\r
static uint8_t sniffUIDType;\r
static uint8_t sniffUID[8] = {0x00};\r
static uint8_t sniffATQA[2] = {0x00};\r
static uint8_t sniffSAK;\r
static uint8_t sniffBuf[16] = {0x00};\r
static uint32_t timerData = 0;\r
\r
\r
bool MfSniffInit(void){\r
	memset(sniffUID, 0x00, 8);\r
	memset(sniffATQA, 0x00, 2);\r
	sniffSAK = 0;\r
	sniffUIDType = SNF_UID_4;\r
\r
	return FALSE;\r
}\r
\r
bool MfSniffEnd(void){\r
	LED_B_ON();\r
	cmd_send(CMD_ACK,0,0,0,0,0);\r
	LED_B_OFF();\r
\r
	return FALSE;\r
}\r
\r
bool RAMFUNC MfSniffLogic(const uint8_t *data, uint16_t len, uint8_t *parity, uint16_t bitCnt, bool reader) {\r
\r
	if (reader && (len == 1) && (bitCnt == 7)) { 		// reset on 7-Bit commands from reader\r
		sniffState = SNF_INIT;\r
	}\r
\r
	switch (sniffState) {\r
		case SNF_INIT:{\r
			if ((len == 1) && (reader) && (bitCnt == 7) ) {  // REQA or WUPA from reader\r
				sniffUIDType = SNF_UID_4;\r
				memset(sniffUID, 0x00, 8);\r
				memset(sniffATQA, 0x00, 2);\r
				sniffSAK = 0;\r
				sniffState = SNF_WUPREQ;\r
			}\r
			break;\r
		}\r
		case SNF_WUPREQ:{\r
			if ((!reader) && (len == 2)) { 		// ATQA from tag\r
				memcpy(sniffATQA, data, 2);\r
				sniffState = SNF_ATQA;\r
			}\r
			break;\r
		}\r
		case SNF_ATQA:{\r
			if ((reader) && (len == 2) && (data[0] == 0x93) && (data[1] == 0x20)) { // Select ALL from reader\r
				sniffState = SNF_ANTICOL1;\r
			}\r
			break;\r
		}\r
		case SNF_ANTICOL1:{\r
			if ((!reader) && (len == 5) && ((data[0] ^ data[1] ^ data[2] ^ data[3]) == data[4])) {  // UID from tag (CL1) \r
				memcpy(sniffUID + 3, data, 4);\r
				sniffState = SNF_UID1;\r
			}\r
			break;\r
		}\r
		case SNF_UID1:{\r
			if ((reader) && (len == 9) && (data[0] == 0x93) && (data[1] == 0x70) && (CheckCrc14443(CRC_14443_A, data, 9))) {   // Select 4 Byte UID from reader\r
				sniffState = SNF_SAK;\r
			}\r
			break;\r
		}\r
		case SNF_SAK:{\r
			if ((!reader) && (len == 3) && (CheckCrc14443(CRC_14443_A, data, 3))) { // SAK from card?\r
				sniffSAK = data[0];\r
				if (sniffUID[3] == 0x88) {			// CL2 UID part to be expected\r
					sniffState = SNF_ANTICOL2;\r
				} else {							// select completed\r
					sniffState = SNF_CARD_IDLE;\r
				}\r
			}\r
			break;\r
		}\r
		case SNF_ANTICOL2:{\r
			if ((!reader) && (len == 5) && ((data[0] ^ data[1] ^ data[2] ^ data[3]) == data[4])) { // CL2 UID \r
				memcpy(sniffUID, sniffUID+4, 3);\r
				memcpy(sniffUID+3, data, 4);\r
				sniffUIDType = SNF_UID_7;\r
				sniffState = SNF_UID2;\r
			}\r
			break;\r
		}\r
		case SNF_UID2:{\r
			if ((reader) && (len == 9) && (data[0] == 0x95) && (data[1] == 0x70) && (CheckCrc14443(CRC_14443_A, data, 9))) {	// Select 2nd part of 7 Byte UID\r
				sniffState = SNF_SAK;\r
			}\r
			break;\r
		}\r
		case SNF_CARD_IDLE:{	// trace the card select sequence\r
			sniffBuf[0] = 0xFF;\r
			sniffBuf[1] = 0xFF;\r
			memcpy(sniffBuf + 2, sniffUID, 7);\r
			memcpy(sniffBuf + 9, sniffATQA, 2);\r
			sniffBuf[11] = sniffSAK;\r
			sniffBuf[12] = 0xFF;\r
			sniffBuf[13] = 0xFF;\r
			LogTrace(sniffBuf, 14, 0, 0, NULL, TRUE);\r
		}	// intentionally no break;\r
		case SNF_CARD_CMD:{		\r
			LogTrace(data, len, 0, 0, NULL, TRUE);\r
			sniffState = SNF_CARD_RESP;\r
			timerData = GetTickCount();\r
			break;\r
		}\r
		case SNF_CARD_RESP:{\r
			LogTrace(data, len, 0, 0, NULL, FALSE);\r
			sniffState = SNF_CARD_CMD;\r
			timerData = GetTickCount();\r
			break;\r
		}\r
	\r
		default:\r
			sniffState = SNF_INIT;\r
		break;\r
	}\r
\r
\r
	return FALSE;\r
}\r
\r
bool RAMFUNC MfSniffSend(uint16_t maxTimeoutMs) {\r
	if (BigBuf_get_traceLen() && (GetTickCount() > timerData + maxTimeoutMs)) {\r
		return intMfSniffSend();\r
	}\r
	return FALSE;\r
}\r
\r
// internal sending function. not a RAMFUNC.\r
bool intMfSniffSend() {\r
\r
	int pckSize = 0;\r
	int pckLen = BigBuf_get_traceLen();\r
	int pckNum = 0;\r
	uint8_t *trace = BigBuf_get_addr();\r
	\r
	FpgaDisableSscDma();\r
	while (pckLen > 0) {\r
		pckSize = MIN(USB_CMD_DATA_SIZE, pckLen);\r
		LED_B_ON();\r
		cmd_send(CMD_ACK, 1, BigBuf_get_traceLen(), pckSize, trace + BigBuf_get_traceLen() - pckLen, pckSize);\r
		LED_B_OFF();\r
\r
		pckLen -= pckSize;\r
		pckNum++;\r
	}\r
\r
	LED_B_ON();\r
	cmd_send(CMD_ACK,2,0,0,0,0);\r
	LED_B_OFF();\r
\r
	clear_trace();\r
	\r
	return TRUE;\r
}\r