/*****************************************************************************
Function:
bool ARPProcess(void)
Summary:
Processes an incoming ARP packet.
Description:
Retrieves an ARP packet from the MAC buffer and determines if it is a
response to our request (in which case the ARP is resolved) or if it
is a request requiring our response (in which case we transmit one.)
Precondition:
ARP packet is ready in the MAC buffer.
Parameters:
None
Return Values:
true - All processing of this ARP packet is complete. Do not call
again until a new ARP packet is waiting in the RX buffer.
false - This function must be called again. More time is needed to
send an ARP response.
***************************************************************************/
bool ARPProcess(void)
{
ARP_PACKET packet;
static NODE_INFO Target;
#if defined(STACK_USE_AUTO_IP)
uint8_t i;
#endif
static enum
{
SM_ARP_IDLE = 0,
SM_ARP_REPLY
} smARP = SM_ARP_IDLE;
switch(smARP)
{
case SM_ARP_IDLE:
// Obtain the incoming ARP packet
MACGetArray((uint8_t*)&packet, sizeof(packet));
MACDiscardRx();
SwapARPPacket(&packet);
// Validate the ARP packet
if ( packet.HardwareType != HW_ETHERNET ||
packet.MACAddrLen != sizeof(MAC_ADDR) ||
packet.ProtocolLen != sizeof(IP_ADDR) )
{
return true;
}
#ifdef STACK_USE_ZEROCONF_LINK_LOCAL
ARPProcessRxPkt(&packet);
#endif
#ifdef STACK_USE_AUTO_IP
if (packet.SenderIPAddr.Val == AppConfig.MyIPAddr.Val)
{
AutoIPConflict(0);
return true;
}
#endif
// Handle incoming ARP responses
#ifdef STACK_CLIENT_MODE
if(packet.Operation == ARP_OPERATION_RESP)
{
/* #if defined(STACK_USE_AUTO_IP)
for (i = 0; i < NETWORK_INTERFACES; i++)
if (AutoIPConfigIsInProgress(i))
AutoIPConflict(i);
#endif*/
Cache.MACAddr = packet.SenderMACAddr;
Cache.IPAddr = packet.SenderIPAddr;
//putsUART("ARPProcess: SM_ARP_IDLE: ARP_OPERATION_RESP \r\n");
return true;
}
#endif
// Handle incoming ARP requests for our MAC address
if(packet.Operation == ARP_OPERATION_REQ)
{
if(packet.TargetIPAddr.Val != AppConfig.MyIPAddr.Val)
{
return true;
}
#ifdef STACK_USE_ZEROCONF_LINK_LOCAL
/* Fix for Loop-Back suppression:
* For ZCLL-Claim packets, host should not respond.
* Check Sender's MAC-address with own MAC-address and
* if it is matched, response will not be sent back. This
* was leading to flooding of ARP-answeres */
if(!memcmp (&packet.SenderMACAddr, &AppConfig.MyMACAddr, 6))
{
putsUART("Loopback answer suppressed \r\n");
return true;
}
#endif
#if defined(STACK_USE_AUTO_IP)
for (i = 0; i < NETWORK_INTERFACES; i++)
if (AutoIPConfigIsInProgress(i))
{
AutoIPConflict(i);
return true;
}
#endif
Target.IPAddr = packet.SenderIPAddr;
Target.MACAddr = packet.SenderMACAddr;
//putsUART("ARPProcess: SM_ARP_IDLE: ARP_OPERATION_REQ \r\n");
smARP = SM_ARP_REPLY;
}
// Do not break. If we get down here, we need to send a reply.
case SM_ARP_REPLY:
packet.Operation = ARP_OPERATION_RESP;
#if defined(STACK_USE_AUTO_IP)
if (AutoIPIsConfigured(0))
{
packet.TargetMACAddr.v[0] = 0xFF;
packet.TargetMACAddr.v[1] = 0xFF;
packet.TargetMACAddr.v[2] = 0xFF;
packet.TargetMACAddr.v[3] = 0xFF;
packet.TargetMACAddr.v[4] = 0xFF;
packet.TargetMACAddr.v[5] = 0xFF;
}
else
#endif
packet.TargetMACAddr = Target.MACAddr;
packet.TargetIPAddr = Target.IPAddr;
#ifdef STACK_USE_ZEROCONF_LINK_LOCAL
packet.SenderIPAddr = AppConfig.MyIPAddr;
#endif
//putsUART("ARPProcess: SM_ARP_REPLY \r\n");
// Send an ARP response to a previously received request
if(!ARPPut(&packet))
{
return false;
}
// Begin listening for ARP requests again
smARP = SM_ARP_IDLE;
break;
}
return true;
}
/*****************************************************************************
Function:
ARP_RESULT ARPProcess(NET_CONFIG* pIf)
Summary:
Processes an incoming ARP packet.
Description:
Retrieves an ARP packet from the MAC buffer and determines if it is a
response to our request (in which case the ARP is resolved) or if it
is a request requiring our response (in which case we transmit one.)
Precondition:
ARP packet is ready in the MAC buffer.
Parameters:
None
Return Values:
ARP_RES_OK - processing OK.
ARP_RES_error - some error occurred
***************************************************************************/
ARP_RESULT ARPProcess(NET_CONFIG* pIf)
{
ARP_PACKET packet;
MAC_ADDR *dstMAC;
OA_HASH_ENTRY *hE;
ARP_CACHE_DCPT *pArpDcpt;
int netIx;
TCPIP_MAC_HANDLE hMac;
ARP_RESULT arpReqRes;
netIx = _TCPIPStackNetIx(pIf);
pArpDcpt = arpCache + netIx;
hMac = _TCPIPStackNetToMac(pIf);
// Obtain the incoming ARP packet and process
MACGetArray(hMac, (uint8_t*)&packet, sizeof(packet));
MACDiscardRx(hMac);
SwapARPPacket(&packet);
// Validate the ARP packet
if ( packet.HardwareType != HW_ETHERNET ||
packet.MACAddrLen != sizeof(MAC_ADDR) ||
packet.ProtocolLen != sizeof(IP_ADDR) )
{
return ARP_RES_OK;
}
#ifdef TCPIP_STACK_USE_ZEROCONF_LINK_LOCAL
ARPProcessRxPkt(pIf, &packet);
#endif
arpReqRes = ARP_RES_OK;
// Handle incoming ARP packet
hE = OAHashLookUp(pArpDcpt->cacheDcpt, &packet.SenderIPAddr.Val);
if(hE != 0)
{ // we already have this sender and we should update it
_ARPUpdateEntry(pIf, (ARP_HASH_ENTRY*)hE, &packet.SenderMACAddr);
}
while(packet.TargetIPAddr.Val == pIf->MyIPAddr.Val)
{ // we are the target and we should add to cache anyway
if(hE == 0)
{ // not there yet
arpReqRes = _ARPAddCompleteEntry(pIf, &packet.SenderIPAddr, &packet.SenderMACAddr);
}
// Handle incoming ARP operation
if(packet.Operation == ARP_OPERATION_REQ)
{
// ARP packet asking for this host IP address
#ifdef TCPIP_STACK_USE_ZEROCONF_LINK_LOCAL
/* Fix for Loop-Back suppression:
* For ZCLL-Claim packets, host should not respond.
* Check Sender's MAC-address with own MAC-address and
* if it is matched, response will not be sent back. This
* was leading to flooding of ARP-answeres */
if(!memcmp (&packet.SenderMACAddr, &pIf->MyMACAddr, 6))
{
SYS_CONSOLE_MESSAGE("Loopback answer suppressed \r\n");
break;
}
#endif
#if defined(TCPIP_STACK_USE_AUTO_IP)
if ((packet.SenderIPAddr.Val == pIf->MyIPAddr.Val) || AutoIPConfigIsInProgress(pIf))
{
AutoIPConflict(pIf);
break;
}
#endif
// Need to send a reply to the requestor
#if defined(TCPIP_STACK_USE_AUTO_IP)
if (AutoIPIsConfigured(pIf))
{
dstMAC = &arpBcastAdd;
}
else
#endif
{
dstMAC = &packet.SenderMACAddr;
}
// Send an ARP response to the received request
if(!ARP_SendIfPkt(pIf, ARP_OPERATION_RESP, (uint32_t)pIf->MyIPAddr.Val, (uint32_t)packet.SenderIPAddr.Val, dstMAC))
{
arpReqRes = ARP_RES_TX_FAILED;
}
}
break;
}
return arpReqRes;
}