From: iceman1001 <iceman@iuse.se>
Date: Fri, 1 May 2015 13:29:19 +0000 (+0200)
Subject: FIX:  the  HF MFU CREAD command on deviceside now can do a proper ATUTHENTICATION... 
X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/commitdiff_plain/062b7cb9561e2109af559d7cd3a4878887bd44db

FIX:  the  HF MFU CREAD command on deviceside now can do a proper ATUTHENTICATION request with 2KEY3DES.
---

diff --git a/armsrc/des.c b/armsrc/des.c
index cb44751f..172b3235 100644
--- a/armsrc/des.c
+++ b/armsrc/des.c
@@ -378,38 +378,54 @@ void tdes_dec(void* out, void* in, const uint8_t* key){
 	des_dec(out, out, (uint8_t*)key + 0);
 }
 
- void tdes_2key_enc(void* out, const void* in, size_t length, const void* key){
+ void tdes_2key_enc(void* out, const void* in, size_t length, const void* key, unsigned char iv[8]){
 
 	if( length % 8 ) return; 
-	
+
+	uint8_t i;
 	uint8_t* tin = (uint8_t*) in;
 	uint8_t* tout = (uint8_t*) out;
 	
 	while( length > 0 )
 	{
+		for( i = 0; i < 8; i++ )
+				tout[i] = (unsigned char)( tin[i] ^ iv[i] );
+		
 		des_enc(tout,  tin, (uint8_t*)key + 0);
 		des_dec(tout, tout, (uint8_t*)key + 8);
 		des_enc(tout, tout, (uint8_t*)key + 0);
 		
+		memcpy( iv, tout, 8 );
+		
 		tin  += 8;
 		tout += 8;
 		length -= 8;
 	}
  }
  
- void tdes_2key_dec(void* out, const void* in, size_t length, const void* key){
+ void tdes_2key_dec(void* out, const void* in, size_t length, const void* key, unsigned char iv[8]){
 	
 	if( length % 8 ) return; 
 
+	uint8_t i;
+	unsigned char temp[8];
+
 	uint8_t* tin = (uint8_t*) in;
 	uint8_t* tout = (uint8_t*) out;
 	
 	while( length > 0 )
 	{
+		memcpy( temp, tin, 8 );
+		
 		des_dec(tout,  tin, (uint8_t*)key + 0);
 		des_enc(tout, tout, (uint8_t*)key + 8);
 		des_dec(tout, tout, (uint8_t*)key + 0);	 	 
 
+		for( i = 0; i < 8; i++ )
+			tout[i] = (unsigned char)( tout[i] ^ iv[i] );
+
+		memcpy( iv, temp, 8 );
+		
 		tin  += 8;
 		tout += 8;
 		length -= 8;
diff --git a/armsrc/des.h b/armsrc/des.h
index 853488c8..880413e9 100644
--- a/armsrc/des.h
+++ b/armsrc/des.h
@@ -97,8 +97,8 @@ void tdes_enc(void* out, const void* in, const void* key);
  */
  void tdes_dec(void* out, const void* in, const void* key);
  
- void tdes_2key_enc(void* out, const void* in, size_t length, const void* key);
- void tdes_2key_dec(void* out, const void* in, size_t length, const void* key);
+ void tdes_2key_enc(void* out, const void* in, size_t length, const void* key, unsigned char iv[8]);
+ void tdes_2key_dec(void* out, const void* in, size_t length, const void* key, unsigned char iv[8]);
 
 #endif /*DES_H_*/
 
diff --git a/armsrc/mifarecmd.c b/armsrc/mifarecmd.c
index 39d3851b..1004e342 100644
--- a/armsrc/mifarecmd.c
+++ b/armsrc/mifarecmd.c
@@ -163,12 +163,11 @@ void MifareUReadBlock(uint8_t arg0, uint8_t arg1, uint8_t *datain)
 		
 		memcpy(key, datain, 16);
 		 
-		uint8_t a[8] = {1,1,1,1,1,1,1,1 };
-		uint8_t b[8] = {0x00};
-		uint8_t enc_b[8] = {0x00};
-		uint8_t ab[16] = {0x00};
-		uint8_t enc_ab[16] = {0x00};		
-		uint8_t enc_key[8] = {0x00};
+		uint8_t random_a[8] = {1,1,1,1,1,1,1,1 };
+		uint8_t random_b[8] = {0x00};
+		uint8_t enc_random_b[8] = {0x00};
+		uint8_t rnd_ab[16] = {0x00};
+		uint8_t IV[8] = {0x00};
 		
 		uint16_t len;
 		uint8_t receivedAnswer[MAX_FRAME_SIZE];
@@ -182,49 +181,72 @@ void MifareUReadBlock(uint8_t arg0, uint8_t arg1, uint8_t *datain)
 		}
 	
 		// tag nonce.
-		memcpy(enc_b,receivedAnswer+1,8);
+		memcpy(enc_random_b,receivedAnswer+1,8);
 
 		// decrypt nonce.
-		tdes_2key_dec(b, enc_b, 8, key );
+		tdes_2key_dec(random_b, enc_random_b, sizeof(random_b), key, IV );
 
-		Dbprintf("enc_B: %02x %02x %02x %02x %02x %02x %02x %02x", enc_b[0],enc_b[1],enc_b[2],enc_b[3],enc_b[4],enc_b[5],enc_b[6],enc_b[7] );
-		Dbprintf("    B: %02x %02x %02x %02x %02x %02x %02x %02x", b[0],b[1],b[2],b[3],b[4],b[5],b[6],b[7] );
-		rol(b,8);
+	
+		rol(random_b,8);
 		
-		memcpy(ab  ,a,8);
-		memcpy(ab+8,b,8);
-
-		Dbprintf("AB: %02x %02x %02x %02x %02x %02x %02x %02x", ab[0],ab[1],ab[2],ab[3],ab[4],ab[5],ab[6],ab[7] );
-		Dbprintf("AB: %02x %02x %02x %02x %02x %02x %02x %02x", ab[8],ab[9],ab[10],ab[11],ab[12],ab[13],ab[14],ab[15] );
-
-		// encrypt
-		tdes_2key_enc(enc_ab, ab, 16, key);
-
-		Dbprintf("e_AB: %02x %02x %02x %02x %02x %02x %02x %02x", enc_ab[0],enc_ab[1],enc_ab[2],enc_ab[3],enc_ab[4],enc_ab[5],enc_ab[6],enc_ab[7] );
-		Dbprintf("e_enc_ab: %02x %02x %02x %02x %02x %02x %02x %02x", enc_ab[8],enc_ab[9],enc_ab[10],enc_ab[11],enc_ab[12],enc_ab[13],enc_ab[14],enc_ab[15] );
+		memcpy(rnd_ab  ,random_a,8);
+		memcpy(rnd_ab+8,random_b,8);
+
+		if (MF_DBGLEVEL >= MF_DBG_EXTENDED) {
+			Dbprintf("enc_B: %02x %02x %02x %02x %02x %02x %02x %02x",
+				enc_random_b[0],enc_random_b[1],enc_random_b[2],enc_random_b[3],
+				enc_random_b[4],enc_random_b[5],enc_random_b[6],enc_random_b[7]);
+				
+			Dbprintf("    B: %02x %02x %02x %02x %02x %02x %02x %02x",
+				random_b[0],random_b[1],random_b[2],random_b[3],
+				random_b[4],random_b[5],random_b[6],random_b[7]);
+
+			Dbprintf("rnd_ab: %02x %02x %02x %02x %02x %02x %02x %02x",
+					rnd_ab[0],rnd_ab[1],rnd_ab[2],rnd_ab[3],
+					rnd_ab[4],rnd_ab[5],rnd_ab[6],rnd_ab[7]);
+					
+			Dbprintf("rnd_ab: %02x %02x %02x %02x %02x %02x %02x %02x",
+					rnd_ab[8],rnd_ab[9],rnd_ab[10],rnd_ab[11],
+					rnd_ab[12],rnd_ab[13],rnd_ab[14],rnd_ab[15] );
+		}
+		
+		// encrypt    out, in, length, key, iv
+		tdes_2key_enc(rnd_ab, rnd_ab, sizeof(rnd_ab), key, enc_random_b);
 
-		len = mifare_sendcmd_short_mfucauth(NULL, 1, 0xAF, enc_ab, receivedAnswer, receivedAnswerPar, NULL);
+		
+		len = mifare_sendcmd_short_mfucauth(NULL, 1, 0xAF, rnd_ab, receivedAnswer, receivedAnswerPar, NULL);
 		if (len != 11) {
 			if (MF_DBGLEVEL >= MF_DBG_ERROR) Dbprintf("Cmd Error: %02x", receivedAnswer[0]);
 			OnError(1);
 			return;
 		}
+
+		uint8_t enc_resp[8] = { 0 };
+		uint8_t resp_random_a[8] = { 0 };
+		memcpy(enc_resp, receivedAnswer+1, 8);
 	
-		// the tags' encryption of our nonce, A.
-		memcpy(enc_key, receivedAnswer+1, 8);
-		
-		// clear B.
-		memset(b, 0x00, 8);
-		
-		// decrypt 
-		tdes_2key_dec(b, enc_key, 8, key );
-		if ( memcmp(a, b, 8) == 0 )
-			Dbprintf("Verified key");
-		else
+		// decrypt    out, in, length, key, iv 
+		tdes_2key_dec(resp_random_a, enc_resp, 8, key, enc_random_b);
+		if ( memcmp(resp_random_a, random_a, 8) != 0 )
 			Dbprintf("failed authentication");
-		
-		Dbprintf("a: %02x %02x %02x %02x %02x %02x %02x %02x", a[0],a[1],a[2],a[3],a[4],a[5],a[6],a[7] );
-		Dbprintf("b: %02x %02x %02x %02x %02x %02x %02x %02x", b[0],b[1],b[2],b[3],b[4],b[5],b[6],b[7] );
+
+		if (MF_DBGLEVEL >= MF_DBG_EXTENDED) {
+			Dbprintf("e_AB: %02x %02x %02x %02x %02x %02x %02x %02x", 
+					rnd_ab[0],rnd_ab[1],rnd_ab[2],rnd_ab[3],
+					rnd_ab[4],rnd_ab[5],rnd_ab[6],rnd_ab[7]);
+
+			Dbprintf("e_AB: %02x %02x %02x %02x %02x %02x %02x %02x",
+					rnd_ab[8],rnd_ab[9],rnd_ab[10],rnd_ab[11],
+					rnd_ab[12],rnd_ab[13],rnd_ab[14],rnd_ab[15]);
+
+			Dbprintf("a: %02x %02x %02x %02x %02x %02x %02x %02x",
+					random_a[0],random_a[1],random_a[2],random_a[3],
+					random_a[4],random_a[5],random_a[6],random_a[7]);
+					
+			Dbprintf("b: %02x %02x %02x %02x %02x %02x %02x %02x",
+					resp_random_a[0],resp_random_a[1],resp_random_a[2],resp_random_a[3],
+					resp_random_a[4],resp_random_a[5],resp_random_a[6],resp_random_a[7]);
+		}
 	}
 		
 	if( mifare_ultra_readblock(blockNo, dataout) ) {
@@ -352,20 +374,13 @@ void MifareUReadCard(uint8_t arg0, int arg1, uint8_t *datain)
 	
 	if (MF_DBGLEVEL >= MF_DBG_EXTENDED) Dbprintf("Pages read %d", countpages);
 
-	// Read a UL-C, EV1,
-	// if lockbits, 
-	if (countpages > 16) 
-		len = Pages*4;
-	else
 		len = Pages*4;
 
-
 	cmd_send(CMD_ACK, 1, 0, 0, dataout, len);	
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 	LEDsoff();
 }
 
-
 //-----------------------------------------------------------------------------
 // Select, Authenticate, Write a MIFARE tag. 
 // read block