From 23b598ee23c1599b849b2f1bff90f48c7751d928 Mon Sep 17 00:00:00 2001
From: iceman1001 <iceman@iuse.se>
Date: Wed, 7 Jan 2015 20:40:22 +0100
Subject: [PATCH] CHG: Minor code clean up. ADD: crc16.c - new crc16_ccitt
 calc.

---
 common/Makefile.common |  4 +++-
 common/cmd.c           |  2 --
 common/crc16.c         | 23 +++++++++++++++++++++++
 common/crc16.h         |  5 +++--
 common/usb_cdc.c       |  8 ++------
 include/usb_cmd.h      |  2 ++
 6 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/common/Makefile.common b/common/Makefile.common
index 2befd456d..2b2bb2fbd 100644
--- a/common/Makefile.common
+++ b/common/Makefile.common
@@ -54,7 +54,8 @@ DELETE=del /q
 MOVE=ren
 COPY=copy
 PATHSEP=\\#
-FLASH_TOOL=winsrc\\prox.exe
+#FLASH_TOOL=winsrc\\prox.exe
+FLASH_TOOL=winsrc\\flash.exe
 DETECTED_OS=Windows
 
 endif
@@ -67,6 +68,7 @@ INCLUDES = ../include/proxmark3.h ../include/at91sam7s512.h ../include/config_gp
 
 CFLAGS =  -c $(INCLUDE) -Wall -Werror -pedantic -std=c99 $(APP_CFLAGS) -Os
 LDFLAGS = -nostartfiles -nodefaultlibs -Wl,-gc-sections -n
+
 LIBS = -lgcc
 
 THUMBOBJ = $(patsubst %.c,$(OBJDIR)/%.o,$(THUMBSRC))
diff --git a/common/cmd.c b/common/cmd.c
index 49d9d9424..0c3ecc1fe 100644
--- a/common/cmd.c
+++ b/common/cmd.c
@@ -34,8 +34,6 @@
 #include "string.h"
 #include "proxmark3.h"
 
-//static UsbCommand txcmd;
-
 bool cmd_receive(UsbCommand* cmd) {
  
   // Check if there is a usb packet available
diff --git a/common/crc16.c b/common/crc16.c
index d181bb2a7..973cd103c 100644
--- a/common/crc16.c
+++ b/common/crc16.c
@@ -8,6 +8,7 @@
 
 #include "crc16.h"
 
+
 unsigned short update_crc16( unsigned short crc, unsigned char c )
 {
   unsigned short i, v, tcrc = 0;
@@ -20,3 +21,25 @@ unsigned short update_crc16( unsigned short crc, unsigned char c )
 
   return ((crc >> 8) ^ tcrc)&0xffff;
 }
+
+uint16_t crc16(uint8_t const *message, int length, uint16_t remainder, uint16_t polynomial) {
+    
+	if (length == 0)
+        return (~remainder);
+			
+    for (int byte = 0; byte < length; ++byte) {
+        remainder ^= (message[byte] << 8);
+        for (uint8_t bit = 8; bit > 0; --bit) {
+            if (remainder & 0x8000) {
+                remainder = (remainder << 1) ^ polynomial;
+            } else {
+                remainder = (remainder << 1);
+            }
+        }
+    }
+    return remainder;
+}
+
+uint16_t crc16_ccitt(uint8_t const *message, int length) {
+    return crc16(message, length, 0xffff, 0x1021);
+}
diff --git a/common/crc16.h b/common/crc16.h
index 055a60bcd..d16d83b5a 100644
--- a/common/crc16.h
+++ b/common/crc16.h
@@ -5,10 +5,11 @@
 //-----------------------------------------------------------------------------
 // CRC16
 //-----------------------------------------------------------------------------
+#include <stdint.h>
 
 #ifndef __CRC16_H
 #define __CRC16_H
-
 unsigned short update_crc16(unsigned short crc, unsigned char c);
-
+uint16_t crc16(uint8_t const *message, int length, uint16_t remainder, uint16_t polynomial);
+uint16_t crc16_ccitt(uint8_t const *message, int length);
 #endif
diff --git a/common/usb_cdc.c b/common/usb_cdc.c
index e2787fb65..54f6a8e81 100644
--- a/common/usb_cdc.c
+++ b/common/usb_cdc.c
@@ -223,7 +223,6 @@ byte_t btReceiveBank   = AT91C_UDP_RX_DATA_BK0;
 void usb_disable() {
   // Disconnect the USB device
   AT91C_BASE_PIOA->PIO_ODR = GPIO_USB_PU;
-//  SpinDelay(100);
   
   // Clear all lingering interrupts
   if(pUdp->UDP_ISR & AT91C_UDP_ENDBUSRES) {
@@ -257,7 +256,6 @@ void usb_enable() {
   
   // Wait for a short while
   for (volatile size_t i=0; i<0x100000; i++);
-//  SpinDelay(100);
 
   // Reconnect USB reconnect
   AT91C_BASE_PIOA->PIO_SODR = GPIO_USB_PU;
@@ -304,8 +302,7 @@ uint32_t usb_read(byte_t* data, size_t len) {
 	uint32_t packetSize, nbBytesRcv = 0;
   uint32_t time_out = 0;
   
-	while (len)
-  {
+	while (len)  {
 		if (!usb_check()) break;
 
 		if ( pUdp->UDP_CSR[AT91C_EP_OUT] & bank ) {
@@ -314,8 +311,7 @@ uint32_t usb_read(byte_t* data, size_t len) {
 			while(packetSize--)
 				data[nbBytesRcv++] = pUdp->UDP_FDR[AT91C_EP_OUT];
 			pUdp->UDP_CSR[AT91C_EP_OUT] &= ~(bank);
-			if (bank == AT91C_UDP_RX_DATA_BK0)
-      {
+			if (bank == AT91C_UDP_RX_DATA_BK0) {
 				bank = AT91C_UDP_RX_DATA_BK1;
       } else {
 				bank = AT91C_UDP_RX_DATA_BK0;
diff --git a/include/usb_cmd.h b/include/usb_cmd.h
index 69c3c1b6a..c2e0b95bd 100644
--- a/include/usb_cmd.h
+++ b/include/usb_cmd.h
@@ -150,8 +150,10 @@ typedef struct {
 
 #define CMD_MIFARE_READBL                                                 0x0620
 #define CMD_MIFAREU_READBL						  0x0720
+
 #define CMD_MIFARE_READSC                                                 0x0621
 #define CMD_MIFAREU_READCARD						  0x0721
+
 #define CMD_MIFARE_WRITEBL                                                0x0622
 #define CMD_MIFAREU_WRITEBL						                          0x0722
 #define CMD_MIFAREU_WRITEBL_COMPAT					                      0x0723