From: Cameron Gutman <aicommander@gmail.com>
Date: Thu, 22 Oct 2009 19:08:02 +0000 (+0000)
Subject:  - Move the DstAddress check above the NCE modification code so we don't use ARP... 
X-Git-Tag: ReactOS-0.3.11~338
X-Git-Url: https://git.reactos.org/?p=reactos.git;a=commitdiff_plain;h=0fba4d8f1126f7bce8991f605b13033facea975a

 - Move the DstAddress check above the NCE modification code so we don't use ARP requests that aren't addressed to us
 - Fixes bug 4879

svn path=/trunk/; revision=43692
---

diff --git a/reactos/lib/drivers/ip/network/arp.c b/reactos/lib/drivers/ip/network/arp.c
index 368b718e03f..a24ff20740a 100644
--- a/reactos/lib/drivers/ip/network/arp.c
+++ b/reactos/lib/drivers/ip/network/arp.c
@@ -212,11 +212,13 @@ VOID ARPReceive(
     SenderProtoAddress = (PVOID)((ULONG_PTR)SenderHWAddress + Header->HWAddrLen);
     TargetProtoAddress = (PVOID)((ULONG_PTR)SenderProtoAddress + Header->ProtoAddrLen + Header->HWAddrLen);
 
-    /* Check if we know the sender */
+    AddrInitIPv4(&DstAddress, *((PULONG)TargetProtoAddress));
+    if (!AddrIsEqual(&DstAddress, &Interface->Unicast))
+        return;
 
     AddrInitIPv4(&SrcAddress, *((PULONG)SenderProtoAddress));
-    AddrInitIPv4(&DstAddress, *((PULONG)TargetProtoAddress));
 
+    /* Check if we know the sender */
     NCE = NBLocateNeighbor(&SrcAddress);
     if (NCE) {
         /* We know the sender. Update the hardware address
@@ -230,8 +232,7 @@ VOID ARPReceive(
             Header->HWAddrLen, 0, ARP_TIMEOUT);
     }
 
-    if (Header->Opcode != ARP_OPCODE_REQUEST ||
-        !AddrIsEqual(&DstAddress, &Interface->Unicast))
+    if (Header->Opcode != ARP_OPCODE_REQUEST)
         return;
 
     /* This is a request for our address. Swap the addresses and