get crc10 and crc6 out of packet-iuup.c

- experimental code for a way-too-heurstic look for iuup dissector


svn path=/trunk/; revision=22341

1 files changed, 37 insertions, 0 deletions

diff --git a/epan/crc6.c b/epan/crc6.c
new file mode 100644
index 0000000000..f6daaf07f0
--- /dev/null
+++ b/epan/crc6.c
@@ -0,0 +1,37 @@
+/*
+ *  crc6.c
+ *  
+ *
+ *  Created by L. E. G. O. on 2007/07/08.
+ *  Copyright 2007 __MyCompanyName__. All rights reserved.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <glib.h>
+#include "crc6.h"
+
+
+guint16 update_crc6_by_bytes(guint16 crc6, guint8 byte1, guint8 byte2) {
+    int bit;
+    guint32 remainder = ( byte1<<8 | byte2 ) << 6;
+    guint32 polynomial = 0x6F << 15;
+	
+    for (bit = 15;
+		 bit >= 0;
+		 --bit)
+    {
+        if (remainder & (0x40 << bit))
+        {
+            remainder ^= polynomial;
+        }
+        polynomial >>= 1;
+    }
+	
+    return (guint16)(remainder ^ crc6);
+}
+
+