X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/7cb8516cb5919cf883c7d3b16f4b5e9f75b586ee..refs/pull/538/head:/client/mifarehost.c

diff --git a/client/mifarehost.c b/client/mifarehost.c
index 5e0f4760..67277b59 100644
--- a/client/mifarehost.c
+++ b/client/mifarehost.c
@@ -8,19 +8,22 @@
 // mifare commands
 //-----------------------------------------------------------------------------
 
+#include "mifarehost.h"
+
 #include <stdio.h>
-#include <stdlib.h> 
+#include <stdlib.h>
 #include <string.h>
 #include <pthread.h>
 
-#include "nonce2key/crapto1.h"
+#include "crapto1/crapto1.h"
 #include "proxmark3.h"
 #include "usb_cmd.h"
 #include "cmdmain.h"
 #include "ui.h"
 #include "util.h"
 #include "iso14443crc.h"
-#include "mifarehost.h"
+
+#include "mifare.h"
 
 // mifare tracer flags used in mfTraceDecode()
 #define TRACE_IDLE		 				0x00
@@ -33,30 +36,236 @@
 #define TRACE_ERROR		 				0xFF
 
 
-// MIFARE
+static int compare_uint64(const void *a, const void *b) {
+	// didn't work: (the result is truncated to 32 bits)
+	//return (*(int64_t*)b - *(int64_t*)a);
+
+	// better:
+	if (*(uint64_t*)b == *(uint64_t*)a) return 0;
+	else if (*(uint64_t*)b < *(uint64_t*)a) return 1;
+	else return -1;
+}
+
+
+// create the intersection (common members) of two sorted lists. Lists are terminated by -1. Result will be in list1. Number of elements is returned.
+static uint32_t intersection(uint64_t *list1, uint64_t *list2)
+{
+	if (list1 == NULL || list2 == NULL) {
+		return 0;
+	}
+	uint64_t *p1, *p2, *p3;
+	p1 = p3 = list1;
+	p2 = list2;
+
+	while ( *p1 != -1 && *p2 != -1 ) {
+		if (compare_uint64(p1, p2) == 0) {
+			*p3++ = *p1++;
+			p2++;
+		}
+		else {
+			while (compare_uint64(p1, p2) < 0) ++p1;
+			while (compare_uint64(p1, p2) > 0) ++p2;
+		}
+	}
+	*p3 = -1;
+	return p3 - list1;
+}
+
+
+// Darkside attack (hf mf mifare)
+static uint32_t nonce2key(uint32_t uid, uint32_t nt, uint32_t nr, uint64_t par_info, uint64_t ks_info, uint64_t **keys) {
+	struct Crypto1State *states;
+	uint32_t i, pos, rr; //nr_diff;
+	uint8_t bt, ks3x[8], par[8][8];
+	uint64_t key_recovered;
+	static uint64_t *keylist;
+	rr = 0;
+
+	// Reset the last three significant bits of the reader nonce
+	nr &= 0xffffff1f;
+
+	for (pos=0; pos<8; pos++) {
+		ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
+		bt = (par_info >> (pos*8)) & 0xff;
+		for (i=0; i<8; i++)	{
+				par[7-pos][i] = (bt >> i) & 0x01;
+		}
+	}
+
+	states = lfsr_common_prefix(nr, rr, ks3x, par, (par_info == 0));
+
+	if (states == NULL) {
+		*keys = NULL;
+		return 0;
+	}
+
+	keylist = (uint64_t*)states;
+
+	for (i = 0; keylist[i]; i++) {
+		lfsr_rollback_word(states+i, uid^nt, 0);
+		crypto1_get_lfsr(states+i, &key_recovered);
+		keylist[i] = key_recovered;
+	}
+	keylist[i] = -1;
+
+	*keys = keylist;
+	return i;
+}
+
+
+int mfDarkside(uint64_t *key)
+{
+	uint32_t uid = 0;
+	uint32_t nt = 0, nr = 0;
+	uint64_t par_list = 0, ks_list = 0;
+	uint64_t *keylist = NULL, *last_keylist = NULL;
+	uint32_t keycount = 0;
+	int16_t isOK = 0;
+
+	UsbCommand c = {CMD_READER_MIFARE, {true, 0, 0}};
+
+	// message
+	printf("-------------------------------------------------------------------------\n");
+	printf("Executing command. Expected execution time: 25sec on average\n");
+	printf("Press button on the proxmark3 device to abort both proxmark3 and client.\n");
+	printf("-------------------------------------------------------------------------\n");
+
+
+	while (true) {
+		clearCommandBuffer();
+		SendCommand(&c);
+
+		//flush queue
+		while (ukbhit()) {
+			int c = getchar(); (void) c;
+		}
+
+		// wait cycle
+		while (true) {
+			printf(".");
+			fflush(stdout);
+			if (ukbhit()) {
+				return -5;
+				break;
+			}
+
+			UsbCommand resp;
+			if (WaitForResponseTimeout(CMD_ACK, &resp, 1000)) {
+				isOK  = resp.arg[0];
+				if (isOK < 0) {
+					return isOK;
+				}
+				uid = (uint32_t)bytes_to_num(resp.d.asBytes +  0, 4);
+				nt =  (uint32_t)bytes_to_num(resp.d.asBytes +  4, 4);
+				par_list = bytes_to_num(resp.d.asBytes +  8, 8);
+				ks_list = bytes_to_num(resp.d.asBytes +  16, 8);
+				nr = bytes_to_num(resp.d.asBytes + 24, 4);
+				break;
+			}
+		}
+
+		if (par_list == 0 && c.arg[0] == true) {
+			PrintAndLog("Parity is all zero. Most likely this card sends NACK on every failed authentication.");
+			PrintAndLog("Attack will take a few seconds longer because we need two consecutive successful runs.");
+		}
+		c.arg[0] = false;
+
+		keycount = nonce2key(uid, nt, nr, par_list, ks_list, &keylist);
+
+		if (keycount == 0) {
+			PrintAndLog("Key not found (lfsr_common_prefix list is null). Nt=%08x", nt);
+			PrintAndLog("This is expected to happen in 25%% of all cases. Trying again with a different reader nonce...");
+			continue;
+		}
+
+		qsort(keylist, keycount, sizeof(*keylist), compare_uint64);
+		keycount = intersection(last_keylist, keylist);
+		if (keycount == 0) {
+			free(last_keylist);
+			last_keylist = keylist;
+			continue;
+		}
+
+		if (keycount > 1) {
+			PrintAndLog("Found %u possible keys. Trying to authenticate with each of them ...\n", keycount);
+		} else {
+			PrintAndLog("Found a possible key. Trying to authenticate...\n");
+		}
+
+		*key = -1;
+		uint8_t keyBlock[USB_CMD_DATA_SIZE];
+		int max_keys = USB_CMD_DATA_SIZE/6;
+		for (int i = 0; i < keycount; i += max_keys) {
+			int size = keycount - i > max_keys ? max_keys : keycount - i;
+			for (int j = 0; j < size; j++) {
+				if (last_keylist == NULL) {
+					num_to_bytes(keylist[i*max_keys + j], 6, keyBlock);
+				} else {
+					num_to_bytes(last_keylist[i*max_keys + j], 6, keyBlock);
+				}
+			}
+			if (!mfCheckKeys(0, 0, false, size, keyBlock, key)) {
+				break;
+			}
+		}
+
+		if (*key != -1) {
+			free(last_keylist);
+			free(keylist);
+			break;
+		} else {
+			PrintAndLog("Authentication failed. Trying again...");
+			free(last_keylist);
+			last_keylist = keylist;
+		}
+	}
+
+	return 0;
+}
+
+
 int mfCheckKeys (uint8_t blockNo, uint8_t keyType, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, uint64_t * key){
 
-	*key = 0;
+	*key = -1;
 
-	UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType&0xff)<<8)), clear_trace, keycnt}};
+	UsbCommand c = {CMD_MIFARE_CHKKEYS, {((blockNo & 0xff) | ((keyType & 0xff) << 8)), clear_trace, keycnt}}; 
 	memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
 	SendCommand(&c);
 
 	UsbCommand resp;
-	if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1;
+	if (!WaitForResponseTimeout(CMD_ACK,&resp,3000)) return 1; 
 	if ((resp.arg[0] & 0xff) != 0x01) return 2;
 	*key = bytes_to_num(resp.d.asBytes, 6);
 	return 0;
 }
 
-int compar_int(const void * a, const void * b) {
-	// didn't work: (the result is truncated to 32 bits)
-	//return (*(uint64_t*)b - *(uint64_t*)a);
+int mfCheckKeysSec(uint8_t sectorCnt, uint8_t keyType, uint8_t timeout14a, bool clear_trace, uint8_t keycnt, uint8_t * keyBlock, sector_t * e_sector){
 
-	// better:
-	if (*(uint64_t*)b == *(uint64_t*)a) return 0;
-	else if (*(uint64_t*)b > *(uint64_t*)a) return 1;
-	else return -1;
+	uint8_t keyPtr = 0;
+
+	if (e_sector == NULL)
+		return -1;
+
+	UsbCommand c = {CMD_MIFARE_CHKKEYS, {((sectorCnt & 0xff) | ((keyType & 0xff) << 8)), (clear_trace | 0x02)|((timeout14a & 0xff) << 8), keycnt}}; 
+	memcpy(c.d.asBytes, keyBlock, 6 * keycnt);
+	SendCommand(&c);
+
+	UsbCommand resp;
+	if (!WaitForResponseTimeoutW(CMD_ACK, &resp, MAX(3000, 1000 + 13 * sectorCnt * keycnt * (keyType == 2 ? 2 : 1)), false)) return 1; // timeout: 13 ms / fail auth
+	if ((resp.arg[0] & 0xff) != 0x01) return 2;
+	
+	bool foundAKey = false;
+	for(int sec = 0; sec < sectorCnt; sec++){
+		for(int keyAB = 0; keyAB < 2; keyAB++){
+			keyPtr = *(resp.d.asBytes + keyAB * 40 + sec);
+			if (keyPtr){
+				e_sector[sec].foundKey[keyAB] = true;
+				e_sector[sec].Key[keyAB] = bytes_to_num(keyBlock + (keyPtr - 1) * 6, 6);
+				foundAKey = true;
+			}
+		}
+	}
+	return foundAKey ? 0 : 3;
 }
 
 // Compare 16 Bits out of cryptostate
@@ -66,7 +275,7 @@ int Compare16Bits(const void * a, const void * b) {
 	else return -1;
 }
 
-typedef 
+typedef
 	struct {
 		union {
 			struct Crypto1State *slhead;
@@ -96,11 +305,11 @@ void* nested_worker_thread(void *arg)
 	statelist->len = p1 - statelist->head.slhead;
 	statelist->tail.sltail = --p1;
 	qsort(statelist->head.slhead, statelist->len, sizeof(uint64_t), Compare16Bits);
-	
+
 	return statelist->head.slhead;
 }
 
-int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t * resultKey, bool calibrate) 
+int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *resultKey, bool calibrate)
 {
 	uint16_t i;
 	uint32_t uid;
@@ -108,10 +317,10 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 
 	StateList_t statelists[2];
 	struct Crypto1State *p1, *p2, *p3, *p4;
-	
+
 	// flush queue
 	WaitForResponseTimeout(CMD_ACK, NULL, 100);
-	
+
 	UsbCommand c = {CMD_MIFARE_NESTED, {blockNo + keyType * 0x100, trgBlockNo + trgKeyType * 0x100, calibrate}};
 	memcpy(c.d.asBytes, key, 6);
 	SendCommand(&c);
@@ -123,10 +332,10 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 	if (resp.arg[0]) {
 		return resp.arg[0];  // error during nested
 	}
-		
+
 	memcpy(&uid, resp.d.asBytes, 4);
 	PrintAndLog("uid:%08x trgbl=%d trgkey=%x", uid, (uint16_t)resp.arg[2] & 0xff, (uint16_t)resp.arg[2] >> 8);
-	
+
 	for (i = 0; i < 2; i++) {
 		statelists[i].blockNo = resp.arg[2] & 0xff;
 		statelists[i].keyType = (resp.arg[2] >> 8) & 0xff;
@@ -134,16 +343,16 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 		memcpy(&statelists[i].nt,  (void *)(resp.d.asBytes + 4 + i * 8 + 0), 4);
 		memcpy(&statelists[i].ks1, (void *)(resp.d.asBytes + 4 + i * 8 + 4), 4);
 	}
-	
+
 	// calc keys
-	
+
 	pthread_t thread_id[2];
-		
+
 	// create and run worker threads
 	for (i = 0; i < 2; i++) {
 		pthread_create(thread_id + i, NULL, nested_worker_thread, &statelists[i]);
 	}
-	
+
 	// wait for threads to terminate:
 	for (i = 0; i < 2; i++) {
 		pthread_join(thread_id[i], (void*)&statelists[i].head.slhead);
@@ -153,7 +362,7 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 	// the first 16 Bits of the cryptostate already contain part of our key.
 	// Create the intersection of the two lists based on these 16 Bits and
 	// roll back the cryptostate
-	p1 = p3 = statelists[0].head.slhead; 
+	p1 = p3 = statelists[0].head.slhead;
 	p2 = p4 = statelists[1].head.slhead;
 	while (p1 <= statelists[0].tail.sltail && p2 <= statelists[1].tail.sltail) {
 		if (Compare16Bits(p1, p2) == 0) {
@@ -178,8 +387,8 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 			while (Compare16Bits(p1, p2) == 1) p2++;
 		}
 	}
-	p3->even = 0; p3->odd = 0;
-	p4->even = 0; p4->odd = 0;
+	*(uint64_t*)p3 = -1;
+	*(uint64_t*)p4 = -1;
 	statelists[0].len = p3 - statelists[0].head.slhead;
 	statelists[1].len = p4 - statelists[1].head.slhead;
 	statelists[0].tail.sltail=--p3;
@@ -187,24 +396,9 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 
 	// the statelists now contain possible keys. The key we are searching for must be in the
 	// intersection of both lists. Create the intersection:
-	qsort(statelists[0].head.keyhead, statelists[0].len, sizeof(uint64_t), compar_int);
-	qsort(statelists[1].head.keyhead, statelists[1].len, sizeof(uint64_t), compar_int);
-
-	uint64_t *p5, *p6, *p7;
-	p5 = p7 = statelists[0].head.keyhead; 
-	p6 = statelists[1].head.keyhead;
-	while (p5 <= statelists[0].tail.keytail && p6 <= statelists[1].tail.keytail) {
-		if (compar_int(p5, p6) == 0) {
-			*p7++ = *p5++;
-			p6++;
-		}
-		else {
-			while (compar_int(p5, p6) == -1) p5++;
-			while (compar_int(p5, p6) == 1) p6++;
-		}
-	}
-	statelists[0].len = p7 - statelists[0].head.keyhead;
-	statelists[0].tail.keytail=--p7;
+	qsort(statelists[0].head.keyhead, statelists[0].len, sizeof(uint64_t), compare_uint64);
+	qsort(statelists[1].head.keyhead, statelists[1].len, sizeof(uint64_t), compare_uint64);
+	statelists[0].len = intersection(statelists[0].head.keyhead, statelists[1].head.keyhead);
 
 	memset(resultKey, 0, 6);
 	// The list may still contain several key candidates. Test each of them with mfCheckKeys
@@ -219,10 +413,10 @@ int mfnested(uint8_t blockNo, uint8_t keyType, uint8_t * key, uint8_t trgBlockNo
 			break;
 		}
 	}
-	
+
 	free(statelists[0].head.slhead);
 	free(statelists[1].head.slhead);
-	
+
 	return 0;
 }
 
@@ -240,7 +434,7 @@ int mfEmlGetMem(uint8_t *data, int blockNum, int blocksCount) {
 
 int mfEmlSetMem(uint8_t *data, int blockNum, int blocksCount) {
 	UsbCommand c = {CMD_MIFARE_EML_MEMSET, {blockNum, blocksCount, 0}};
-	memcpy(c.d.asBytes, data, blocksCount * 16); 
+	memcpy(c.d.asBytes, data, blocksCount * 16);
 	SendCommand(&c);
 	return 0;
 }
@@ -253,7 +447,7 @@ int mfCGetBlock(uint8_t blockNo, uint8_t *data, uint8_t params) {
 	UsbCommand c = {CMD_MIFARE_CGETBLOCK, {params, 0, blockNo}};
 	SendCommand(&c);
 
-  UsbCommand resp;
+	UsbCommand resp;
 	if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {
 		isOK  = resp.arg[0] & 0xff;
 		memcpy(data, resp.d.asBytes, 16);
@@ -269,29 +463,54 @@ int mfCSetBlock(uint8_t blockNo, uint8_t *data, uint8_t *uid, bool wantWipe, uin
 
 	uint8_t isOK = 0;
 	UsbCommand c = {CMD_MIFARE_CSETBLOCK, {wantWipe, params & (0xFE | (uid == NULL ? 0:1)), blockNo}};
-	memcpy(c.d.asBytes, data, 16); 
+	memcpy(c.d.asBytes, data, 16);
 	SendCommand(&c);
 
-  UsbCommand resp;
-	if (WaitForResponseTimeout(CMD_ACK,&resp,1500)) {
+	UsbCommand resp;
+	if (WaitForResponseTimeout(CMD_ACK, &resp, 1500)) {
 		isOK  = resp.arg[0] & 0xff;
-		if (uid != NULL) 
+		if (uid != NULL)
 			memcpy(uid, resp.d.asBytes, 4);
-		if (!isOK) 
+		if (!isOK)
 			return 2;
 	} else {
 		PrintAndLog("Command execute timeout");
 		return 1;
 	}
+
 	return 0;
 }
 
-int mfCSetUID(uint8_t *uid, uint8_t *atqa, uint8_t *sak, uint8_t *oldUID, bool wantWipe) {
+int mfCWipe(uint32_t numSectors, bool gen1b, bool wantWipe, bool wantFill) {
+	uint8_t isOK = 0;
+	uint8_t cmdParams = wantWipe + wantFill * 0x02 + gen1b * 0x04;
+	UsbCommand c = {CMD_MIFARE_CWIPE, {numSectors, cmdParams, 0}};
+	SendCommand(&c);
+
+	UsbCommand resp;
+	WaitForResponse(CMD_ACK,&resp);
+	isOK  = resp.arg[0] & 0xff;
+	
+	return isOK;
+}
+
+int mfCSetUID(uint8_t *uid, uint8_t *atqa, uint8_t *sak, uint8_t *oldUID) {
 	uint8_t oldblock0[16] = {0x00};
 	uint8_t block0[16] = {0x00};
+	int gen = 0, res;
+
+	gen = mfCIdentify();
 
-	int old = mfCGetBlock(0, oldblock0, CSETBLOCK_SINGLE_OPER);
-	if (old == 0) {
+	/* generation 1a magic card by default */
+	uint8_t cmdParams = CSETBLOCK_SINGLE_OPER;
+	if (gen == 2) {
+		/* generation 1b magic card */
+		cmdParams = CSETBLOCK_SINGLE_OPER | CSETBLOCK_MAGIC_1B;
+	}
+	
+	res = mfCGetBlock(0, oldblock0, cmdParams);
+
+	if (res == 0) {
 		memcpy(block0, oldblock0, 16);
 		PrintAndLog("old block 0:  %s", sprint_hex(block0,16));
 	} else {
@@ -300,20 +519,44 @@ int mfCSetUID(uint8_t *uid, uint8_t *atqa, uint8_t *sak, uint8_t *oldUID, bool w
 
 	// fill in the new values
 	// UID
-	memcpy(block0, uid, 4); 
+	memcpy(block0, uid, 4);
 	// Mifare UID BCC
-	block0[4] = block0[0]^block0[1]^block0[2]^block0[3];
+	block0[4] = block0[0] ^ block0[1] ^ block0[2] ^ block0[3];
 	// mifare classic SAK(byte 5) and ATQA(byte 6 and 7, reversed)
-	if (sak!=NULL)
-		block0[5]=sak[0];
-	if (atqa!=NULL) {
-		block0[6]=atqa[1];
-		block0[7]=atqa[0];
-	}
-	PrintAndLog("new block 0:  %s", sprint_hex(block0,16));
-	return mfCSetBlock(0, block0, oldUID, wantWipe, CSETBLOCK_SINGLE_OPER);
+	if (sak != NULL)
+		block0[5] = sak[0];
+	if (atqa != NULL) {
+		block0[6] = atqa[1];
+		block0[7] = atqa[0];
+	}
+	PrintAndLog("new block 0:  %s", sprint_hex(block0, 16));
+
+	res = mfCSetBlock(0, block0, oldUID, false, cmdParams);
+	if (res) {
+		PrintAndLog("Can't set block 0. Error: %d", res);
+		return res;
+	}
+	
+	return 0;
 }
 
+int mfCIdentify() {
+	UsbCommand c = {CMD_MIFARE_CIDENT, {0, 0, 0}};
+	SendCommand(&c);
+	UsbCommand resp;
+	WaitForResponse(CMD_ACK,&resp);
+
+	uint8_t isGeneration = resp.arg[0] & 0xff;
+	switch( isGeneration ){
+		case 1: PrintAndLog("Chinese magic backdoor commands (GEN 1a) detected"); break;
+		case 2: PrintAndLog("Chinese magic backdoor command (GEN 1b) detected"); break;
+		default: PrintAndLog("No chinese magic backdoor command detected"); break;
+	}
+
+	return (int) isGeneration;
+}
+
+
 // SNIFFER
 
 // constants
@@ -345,7 +588,7 @@ int isTraceCardEmpty(void) {
 }
 
 int isBlockEmpty(int blockN) {
-	for (int i = 0; i < 16; i++) 
+	for (int i = 0; i < 16; i++)
 		if (traceCard[blockN * 16 + i] != 0) return 0;
 
 	return 1;
@@ -357,15 +600,15 @@ int isBlockTrailer(int blockN) {
 
 int saveTraceCard(void) {
 	FILE * f;
-	
+
 	if ((!strlen(traceFileName)) || (isTraceCardEmpty())) return 0;
-	
+
 	f = fopen(traceFileName, "w+");
 	if ( !f ) return 1;
-	
+
 	for (int i = 0; i < 64; i++) {  // blocks
 		for (int j = 0; j < 16; j++)  // bytes
-			fprintf(f, "%02x", *(traceCard + i * 16 + j)); 
+			fprintf(f, "%02x", *(traceCard + i * 16 + j));
 		fprintf(f,"\n");
 	}
 	fclose(f);
@@ -377,10 +620,10 @@ int loadTraceCard(uint8_t *tuid) {
 	char buf[64] = {0x00};
 	uint8_t buf8[64] = {0x00};
 	int i, blockNum;
-	
-	if (!isTraceCardEmpty()) 
+
+	if (!isTraceCardEmpty())
 		saveTraceCard();
-		
+
 	memset(traceCard, 0x00, 4096);
 	memcpy(traceCard, tuid + 3, 4);
 
@@ -388,11 +631,11 @@ int loadTraceCard(uint8_t *tuid) {
 
 	f = fopen(traceFileName, "r");
 	if (!f) return 1;
-	
+
 	blockNum = 0;
-		
+
 	while(!feof(f)){
-	
+
 		memset(buf, 0, sizeof(buf));
 		if (fgets(buf, sizeof(buf), f) == NULL) {
 			PrintAndLog("File reading error.");
@@ -420,20 +663,20 @@ int loadTraceCard(uint8_t *tuid) {
 
 int mfTraceInit(uint8_t *tuid, uint8_t *atqa, uint8_t sak, bool wantSaveToEmlFile) {
 
-	if (traceCrypto1) 
+	if (traceCrypto1)
 		crypto1_destroy(traceCrypto1);
 
 	traceCrypto1 = NULL;
 
-	if (wantSaveToEmlFile) 
+	if (wantSaveToEmlFile)
 		loadTraceCard(tuid);
-		
+
 	traceCard[4] = traceCard[0] ^ traceCard[1] ^ traceCard[2] ^ traceCard[3];
 	traceCard[5] = sak;
 	memcpy(&traceCard[6], atqa, 2);
 	traceCurBlock = 0;
 	uid = bytes_to_num(tuid + 3, 4);
-	
+
 	traceState = TRACE_IDLE;
 
 	return 0;
@@ -442,7 +685,7 @@ int mfTraceInit(uint8_t *tuid, uint8_t *atqa, uint8_t sak, bool wantSaveToEmlFil
 void mf_crypto1_decrypt(struct Crypto1State *pcs, uint8_t *data, int len, bool isEncrypted){
 	uint8_t	bt = 0;
 	int i;
-	
+
 	if (len != 1) {
 		for (i = 0; i < len; i++)
 			data[i] = crypto1_byte(pcs, 0x00, isEncrypted) ^ data[i];
@@ -450,7 +693,7 @@ void mf_crypto1_decrypt(struct Crypto1State *pcs, uint8_t *data, int len, bool i
 		bt = 0;
 		for (i = 0; i < 4; i++)
 			bt |= (crypto1_bit(pcs, 0, isEncrypted) ^ BIT(data[0], i)) << i;
-				
+
 		data[0] = bt;
 	}
 	return;
@@ -465,24 +708,24 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		traceState = TRACE_ERROR;
 		return 1;
 	}
-	
+
 	memcpy(data, data_src, len);
 	if ((traceCrypto1) && ((traceState == TRACE_IDLE) || (traceState > TRACE_AUTH_OK))) {
 		mf_crypto1_decrypt(traceCrypto1, data, len, 0);
 		PrintAndLog("dec> %s", sprint_hex(data, len));
-		AddLogHex(logHexFileName, "dec> ", data, len); 
+		AddLogHex(logHexFileName, "dec> ", data, len);
 	}
-	
+
 	switch (traceState) {
-	case TRACE_IDLE: 
+	case TRACE_IDLE:
 		// check packet crc16!
 		if ((len >= 4) && (!CheckCrc14443(CRC_14443_A, data, len))) {
 			PrintAndLog("dec> CRC ERROR!!!");
-			AddLogLine(logHexFileName, "dec> ", "CRC ERROR!!!"); 
+			AddLogLine(logHexFileName, "dec> ", "CRC ERROR!!!");
 			traceState = TRACE_ERROR;  // do not decrypt the next commands
 			return 1;
 		}
-		
+
 		// AUTHENTICATION
 		if ((len ==4) && ((data[0] == 0x60) || (data[0] == 0x61))) {
 			traceState = TRACE_AUTH1;
@@ -510,11 +753,11 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 			traceState = TRACE_ERROR;  // do not decrypt the next commands
 			return 0;
 		}
-		
+
 		return 0;
 	break;
-	
-	case TRACE_READ_DATA: 
+
+	case TRACE_READ_DATA:
 		if (len == 18) {
 			traceState = TRACE_IDLE;
 
@@ -531,7 +774,7 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		}
 	break;
 
-	case TRACE_WRITE_OK: 
+	case TRACE_WRITE_OK:
 		if ((len == 1) && (data[0] == 0x0a)) {
 			traceState = TRACE_WRITE_DATA;
 
@@ -542,7 +785,7 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		}
 	break;
 
-	case TRACE_WRITE_DATA: 
+	case TRACE_WRITE_DATA:
 		if (len == 18) {
 			traceState = TRACE_IDLE;
 
@@ -555,7 +798,7 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		}
 	break;
 
-	case TRACE_AUTH1: 
+	case TRACE_AUTH1:
 		if (len == 4) {
 			traceState = TRACE_AUTH2;
 			nt = bytes_to_num(data, 4);
@@ -566,7 +809,7 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		}
 	break;
 
-	case TRACE_AUTH2: 
+	case TRACE_AUTH2:
 		if (len == 8) {
 			traceState = TRACE_AUTH_OK;
 
@@ -579,12 +822,12 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		}
 	break;
 
-	case TRACE_AUTH_OK: 
+	case TRACE_AUTH_OK:
 		if (len ==4) {
 			traceState = TRACE_IDLE;
 
 			at_enc = bytes_to_num(data, 4);
-			
+
 			//  decode key here)
 			ks2 = ar_enc ^ prng_successor(nt, 64);
 			ks3 = at_enc ^ prng_successor(nt, 96);
@@ -596,11 +839,11 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 
 			crypto1_get_lfsr(revstate, &lfsr);
 			printf("key> %x%x\n", (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF));
-			AddLogUint64(logHexFileName, "key> ", lfsr); 
-			
+			AddLogUint64(logHexFileName, "key> ", lfsr);
+
 			int blockShift = ((traceCurBlock & 0xFC) + 3) * 16;
 			if (isBlockEmpty((traceCurBlock & 0xFC) + 3)) memcpy(traceCard + blockShift + 6, trailerAccessBytes, 4);
-			
+
 			if (traceCurKey) {
 				num_to_bytes(lfsr, 6, traceCard + blockShift + 10);
 			} else {
@@ -611,10 +854,10 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 			if (traceCrypto1) {
 				crypto1_destroy(traceCrypto1);
 			}
-			
+
 			// set cryptosystem state
 			traceCrypto1 = lfsr_recovery64(ks2, ks3);
-			
+
 //	nt = crypto1_word(traceCrypto1, nt ^ uid, 1) ^ nt;
 
 	/*	traceCrypto1 = crypto1_create(lfsr); // key in lfsr
@@ -622,7 +865,7 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		crypto1_word(traceCrypto1, ar, 1);
 		crypto1_word(traceCrypto1, 0, 0);
 		crypto1_word(traceCrypto1, 0, 0);*/
-	
+
 			return 0;
 		} else {
 			traceState = TRACE_ERROR;
@@ -630,7 +873,7 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 		}
 	break;
 
-	default: 
+	default:
 		traceState = TRACE_ERROR;
 		return 1;
 	}
@@ -638,6 +881,8 @@ int mfTraceDecode(uint8_t *data_src, int len, bool wantSaveToEmlFile) {
 	return 0;
 }
 
+// DECODING
+
 int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data, int len){
 	/*
 	uint32_t nt;      // tag challenge
@@ -657,3 +902,73 @@ int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data,
 	crypto1_destroy(traceCrypto1);
 	return 0;
 }
+
+/** validate_prng_nonce
+ * Determine if nonce is deterministic. ie: Suspectable to Darkside attack.
+ * returns
+ *   true = weak prng
+ *   false = hardend prng
+ */
+bool validate_prng_nonce(uint32_t nonce) {
+	uint16_t *dist = 0;
+	uint16_t x, i;
+
+	dist = malloc(2 << 16);
+	if(!dist)
+		return -1;
+
+	// init prng table:
+	for (x = i = 1; i; ++i) {
+		dist[(x & 0xff) << 8 | x >> 8] = i;
+		x = x >> 1 | (x ^ x >> 2 ^ x >> 3 ^ x >> 5) << 15;
+	}
+	
+	uint32_t res = (65535 - dist[nonce >> 16] + dist[nonce & 0xffff]) % 65535;
+	
+	free(dist);	
+	return (res == 16);
+}
+
+/* Detect Tag Prng, 
+* function performs a partial AUTH,  where it tries to authenticate against block0, key A, but only collects tag nonce.
+* the tag nonce is check to see if it has a predictable PRNG.
+* @returns 
+*	TRUE if tag uses WEAK prng (ie Now the NACK bug also needs to be present for Darkside attack)
+*   FALSE is tag uses HARDEND prng (ie hardnested attack possible, with known key)
+*/
+int DetectClassicPrng(void){
+
+	UsbCommand resp, respA;	
+	uint8_t cmd[] = {0x60, 0x00}; // MIFARE_AUTH_KEYA
+	uint32_t flags = ISO14A_CONNECT | ISO14A_RAW | ISO14A_APPEND_CRC | ISO14A_NO_RATS;
+	
+	UsbCommand c = {CMD_READER_ISO_14443a, {flags, sizeof(cmd), 0}};
+	memcpy(c.d.asBytes, cmd, sizeof(cmd));
+
+	clearCommandBuffer();
+	SendCommand(&c);
+	if (!WaitForResponseTimeout(CMD_ACK, &resp, 2000)) {
+        PrintAndLog("PRNG UID: Reply timeout.");
+		return -1;
+	}
+	
+	// if select tag failed.
+	if (resp.arg[0] == 0) {
+		PrintAndLog("PRNG error: selecting tag failed, can't detect prng.");
+		return -1;
+	}
+	
+	if (!WaitForResponseTimeout(CMD_ACK, &respA, 5000)) {
+        PrintAndLog("PRNG data: Reply timeout.");
+		return -1;
+	}
+
+	// check respA
+	if (respA.arg[0] != 4) {
+		PrintAndLog("PRNG data error: Wrong length: %d", respA.arg[0]);
+		return -1;
+	}
+
+	uint32_t nonce = bytes_to_num(respA.d.asBytes, respA.arg[0]);
+	return validate_prng_nonce(nonce);
+}