ADD: PACE functionality ref: https://github.com/Proxmark/proxmark3/pull/121

FIX:  some missing usb_commands for EPA.

armsrc/epa.c

@@ -5,7 +5,7 @@
 // at your option, any later version. See the LICENSE.txt file for the text of
 // the license.
 //-----------------------------------------------------------------------------
-// Routines to support the German eletronic "Personalausweis" (ID card)
+// Routines to support the German electronic "Personalausweis" (ID card)
 // Note that the functions which do not implement USB commands do NOT initialize
 // the card (with iso14443a_select_card etc.). If You want to use these
 // functions, You need to do the setup before calling them!
@@ -13,8 +13,7 @@
 
 #include "iso14443a.h"
 #include "epa.h"
-#include "../common/cmd.h"
-
+#include "cmd.h"
 
 // Protocol and Parameter Selection Request
 // use regular (1x) speed in both directions
@@ -75,6 +74,32 @@ static const uint8_t oid_pace_start[] = {
     0x04 // id-PACE
 };
 
+// APDUs for replaying:
+// MSE: Set AT (initiate PACE)
+static uint8_t apdu_replay_mse_set_at_pace[41];
+// General Authenticate (Get Nonce)
+static uint8_t apdu_replay_general_authenticate_pace_get_nonce[8];
+// General Authenticate (Map Nonce)
+static uint8_t apdu_replay_general_authenticate_pace_map_nonce[75];
+// General Authenticate (Mutual Authenticate)
+static uint8_t apdu_replay_general_authenticate_pace_mutual_authenticate[75];
+// General Authenticate (Perform Key Agreement)
+static uint8_t apdu_replay_general_authenticate_pace_perform_key_agreement[18];
+// pointers to the APDUs (for iterations)
+static struct {
+	uint8_t len;
+	uint8_t *data;
+} const apdus_replay[] = {
+	{sizeof(apdu_replay_mse_set_at_pace), apdu_replay_mse_set_at_pace},
+	{sizeof(apdu_replay_general_authenticate_pace_get_nonce), apdu_replay_general_authenticate_pace_get_nonce},
+	{sizeof(apdu_replay_general_authenticate_pace_map_nonce), apdu_replay_general_authenticate_pace_map_nonce},
+	{sizeof(apdu_replay_general_authenticate_pace_mutual_authenticate), apdu_replay_general_authenticate_pace_mutual_authenticate},
+	{sizeof(apdu_replay_general_authenticate_pace_perform_key_agreement), apdu_replay_general_authenticate_pace_perform_key_agreement}
+};
+
+// lengths of the replay APDUs
+static uint8_t apdu_lengths_replay[5];
+
 //-----------------------------------------------------------------------------
 // Closes the communication channel and turns off the field
 //-----------------------------------------------------------------------------
@@ -216,11 +241,6 @@ int EPA_Read_CardAccess(uint8_t *buffer, size_t max_length)
 //-----------------------------------------------------------------------------
 static void EPA_PACE_Collect_Nonce_Abort(uint8_t step, int func_return)
 {
-//	// step in which the failure occured
-//	ack->arg[0] = step;
-//	// last return code
-//	ack->arg[1] = func_return;
-
 	// power down the field
 	EPA_Finish();
 	
@@ -247,15 +267,10 @@ void EPA_PACE_Collect_Nonce(UsbCommand *c)
 	// return value of a function
 	int func_return = 0;
 
-//	// initialize ack with 0s
-//	memset(ack->arg, 0, 12);
-//	memset(ack->d.asBytes, 0, 48);
-	
 	// set up communication
 	func_return = EPA_Setup();
 	if (func_return != 0) {	
 		EPA_PACE_Collect_Nonce_Abort(1, func_return);
-		Dbprintf("epa: setup fucked up! %d", func_return);
 		return;
 	}
 
@@ -265,13 +280,10 @@ void EPA_PACE_Collect_Nonce(UsbCommand *c)
 	int card_access_length = EPA_Read_CardAccess(card_access, 256);
 	// the response has to be at least this big to hold the OID
 	if (card_access_length < 18) {
-		Dbprintf("epa: Too small!");
 		EPA_PACE_Collect_Nonce_Abort(2, card_access_length);
 		return;
 	}
 
-	Dbprintf("epa: foo!");
-	
 	// this will hold the PACE info of the card
 	pace_version_info_t pace_version_info;
 	// search for the PACE OID
@@ -283,8 +295,6 @@ void EPA_PACE_Collect_Nonce(UsbCommand *c)
 		return;
 	}
 	
-	Dbprintf("epa: bar!");
-	
 	// initiate the PACE protocol
 	// use the CAN for the password since that doesn't change
 	func_return = EPA_PACE_MSE_Set_AT(pace_version_info, 2);
@@ -304,8 +314,6 @@ void EPA_PACE_Collect_Nonce(UsbCommand *c)
 	EPA_Finish();
 	
 	// save received information
-//	ack->arg[1] = func_return;
-//	memcpy(ack->d.asBytes, nonce, func_return);
 	cmd_send(CMD_ACK,0,func_return,0,nonce,func_return);
 }
 
@@ -414,13 +422,79 @@ int EPA_PACE_MSE_Set_AT(pace_version_info_t pace_version_info, uint8_t password)
 	return 0;
 }
 
+//-----------------------------------------------------------------------------
+// Perform the PACE protocol by replaying given APDUs
+//-----------------------------------------------------------------------------
+void EPA_PACE_Replay(UsbCommand *c)
+{
+	uint32_t timings[sizeof(apdu_lengths_replay) / sizeof(apdu_lengths_replay[0])] = {0};
+
+	// if an APDU has been passed, save it
+	if (c->arg[0] != 0) {
+		// make sure it's not too big
+		if(c->arg[2] > apdus_replay[c->arg[0] - 1].len)
+		{
+			cmd_send(CMD_ACK, 1, 0, 0, NULL, 0);
+		}
+		memcpy(apdus_replay[c->arg[0] - 1].data + c->arg[1],
+	           c->d.asBytes,
+	           c->arg[2]);
+		// save/update APDU length
+		if (c->arg[1] == 0) {
+			apdu_lengths_replay[c->arg[0] - 1] = c->arg[2];
+		} else {
+			apdu_lengths_replay[c->arg[0] - 1] += c->arg[2];
+		}
+		cmd_send(CMD_ACK, 0, 0, 0, NULL, 0);
+		return;
+	}
+
+	// return value of a function
+	int func_return;
+
+	// set up communication
+	func_return = EPA_Setup();
+	if (func_return != 0) {
+		EPA_Finish();
+		cmd_send(CMD_ACK, 2, func_return, 0, NULL, 0);
+		return;
+	}
+
+	// increase the timeout (at least some cards really do need this!)/////////////
+	// iso14a_set_timeout(0x0003FFFF);
+
+	// response APDU
+	uint8_t response_apdu[300] = {0};
+
+	// now replay the data and measure the timings
+	for (int i = 0; i < sizeof(apdu_lengths_replay); i++) {
+		StartCountUS();
+		func_return = iso14_apdu(apdus_replay[i].data,
+		                         apdu_lengths_replay[i],
+		                         response_apdu);
+		timings[i] = GetCountUS();
+		// every step but the last one should succeed
+		if (i < sizeof(apdu_lengths_replay) - 1
+		    && (func_return < 6
+		        || response_apdu[func_return - 4] != 0x90
+		        || response_apdu[func_return - 3] != 0x00))
+		{
+			EPA_Finish();
+			cmd_send(CMD_ACK, 3 + i, func_return, 0, timings, 20);
+			return;
+		}
+	}
+	EPA_Finish();
+	cmd_send(CMD_ACK,0,0,0,timings,20);
+	return;
+}
+
 //-----------------------------------------------------------------------------
 // Set up a communication channel (Card Select, PPS)
 // Returns 0 on success or a non-zero error code on failure
 //-----------------------------------------------------------------------------
 int EPA_Setup()
 {
-
 	int return_code = 0;
 	uint8_t uid[10];
 	uint8_t pps_response[3];
@@ -429,20 +503,16 @@ int EPA_Setup()
 
 	// power up the field
 	iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
-	
 	// select the card
 	return_code = iso14443a_select_card(uid, &card_select_info, NULL);
 	if (return_code != 1) {
-		Dbprintf("Epa: Can't select card");
 		return 1;
 	}
-
 	// send the PPS request
 	ReaderTransmit((uint8_t *)pps, sizeof(pps), NULL);
 	return_code = ReaderReceive(pps_response, pps_response_par);
 	if (return_code != 3 || pps_response[0] != 0xD0) {
 		return return_code == 0 ? 2 : return_code;
 	}
-	
 	return 0;
-}
+}