[cgutman] 43638: - Fix a typo in checksum calculation for datagrams with an odd number of octets - Allow packets with no checksum - Remove debug prints that got left behind

Author: cgutman
Date: Tue Oct 20 08:07:34 2009
New Revision: 43638

URL: http://svn.reactos.org/svn/reactos?rev=43638&view=rev
Log:
 - Fix a typo in checksum calculation for datagrams with an odd number of octets
 - Allow packets with no checksum
 - Remove debug prints that got left behind

Modified:
    trunk/reactos/lib/drivers/ip/network/checksum.c
    trunk/reactos/lib/drivers/ip/transport/udp/udp.c

Modified: trunk/reactos/lib/drivers/ip/network/checksum.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/lib/drivers/ip/network/che…
==============================================================================
--- trunk/reactos/lib/drivers/ip/network/checksum.c [iso-8859-1] (original)
+++ trunk/reactos/lib/drivers/ip/network/checksum.c [iso-8859-1] Tue Oct 20 08:07:34 2009
@@ -69,16 +69,14 @@
 
   /* Pad the data if needed */
   Pad = (DataLength & 1);
-  if (Pad) {
-      DbgPrint("Odd\n");
+  if (Pad)
       DataLength++;
-  } else DbgPrint("Even\n");
 
   /* Add from the UDP header and data */
   for (i = 0; i < DataLength; i += 2)
   {
        TmpSum = ((PacketBuffer[i] << 8) & 0xFF00) +
-                ((Pad && i == DataLength - 1) ? 0 : (PacketBuffer[i+1] &
0x00FF));
+                ((Pad && i == DataLength - 2) ? 0 : (PacketBuffer[i+1] &
0x00FF));
        Sum += TmpSum;
   }
 

Modified: trunk/reactos/lib/drivers/ip/transport/udp/udp.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/lib/drivers/ip/transport/u…
==============================================================================
--- trunk/reactos/lib/drivers/ip/transport/udp/udp.c [iso-8859-1] (original)
+++ trunk/reactos/lib/drivers/ip/transport/udp/udp.c [iso-8859-1] Tue Oct 20 08:07:34
2009
@@ -267,7 +267,7 @@
   i = UDPv4ChecksumCalculate(IPv4Header,
                              (PUCHAR)UDPHeader,
                              WH2N(UDPHeader->Length));
-  if (i != DH2N(0x0000FFFF))
+  if (i != DH2N(0x0000FFFF) && UDPHeader->Checksum != 0)
   {
       TI_DbgPrint(MIN_TRACE, ("Bad checksum on packet received.\n"));
       return;