/**
*
* This function will send a Echo request packet.
*
* @param InstancePtr is a pointer to the instance of the EmacLite.
*
* @return None.
*
* @note None.
*
******************************************************************************/
static void SendEchoReqFrame(XEmacLite *InstancePtr)
{
u16 *TempPtr;
u16 *TxFramePtr;
u16 *RxFramePtr;
u16 CheckSum;
u32 NextTxBuffBaseAddr;
int Index;
TxFramePtr = (u16 *)TxFrame;
RxFramePtr = (u16 *)RxFrame;
/*
* Determine the next expected transmit buffer base address.
*/
NextTxBuffBaseAddr = XEmacLite_NextTransmitAddr(InstancePtr);
/*
* Add Destination MAC Address.
*/
Index = MAC_ADDR_LEN;
while (Index--) {
*(TxFramePtr + Index) = *(DestMacAddr + Index);
}
/*
* Add Source MAC Address.
*/
Index = MAC_ADDR_LEN;
TempPtr = (u16 *)LocalMacAddr;
while (Index--) {
*(TxFramePtr + (Index + SRC_MAC_ADDR_LOC )) =
*(TempPtr + Index);
}
/*
* Add IP header information.
*/
Index = IP_START_LOC;
while (Index--) {
*(TxFramePtr + (Index + ETHER_PROTO_TYPE_LOC )) =
Xil_Htons(*(IpHeaderInfo + Index));
}
/*
* Add Source IP address.
*/
Index = IP_ADDR_LEN;
TempPtr = (u16 *)LocalIpAddress;
while (Index--) {
*(TxFramePtr + (Index + IP_REQ_SRC_IP_LOC )) =
*(TempPtr + Index);
}
/*
* Add Destination IP address.
*/
Index = IP_ADDR_LEN;
TempPtr = (u16 *)DestIpAddress;
while (Index--) {
*(TxFramePtr + (Index + IP_REQ_DEST_IP_LOC )) =
*(TempPtr + Index);
}
/*
* Checksum is calculated for IP field and added in the frame.
*/
CheckSum = CheckSumCalculation((u16 *)TxFrame, IP_START_LOC,
IP_HEADER_LEN);
CheckSum = ~CheckSum;
*(TxFramePtr + IP_CHECKSUM_LOC) = Xil_Htons(CheckSum);
/*
* Add echo field information.
*/
*(TxFramePtr + ICMP_ECHO_FIELD_LOC) = Xil_Htons(XEL_ETHER_PROTO_TYPE_IP);
/*
* Checksum value is initialized to zeros.
*/
*(TxFramePtr + ICMP_DATA_LEN) = 0x0000;
/*
* Add identifier and sequence number to the frame.
*/
*(TxFramePtr + ICMP_IDEN_FIELD_LOC) = (IDEN_NUM);
*(TxFramePtr + (ICMP_IDEN_FIELD_LOC + 1)) = Xil_Htons((u16)(++SeqNum));
/*
* Add known data to the frame.
*/
Index = ICMP_KNOWN_DATA_LEN;
while (Index--) {
*(TxFramePtr + (Index + ICMP_KNOWN_DATA_LOC)) =
Xil_Htons(*(IcmpData + Index));
}
/*
* Checksum is calculated for Data Field and added in the frame.
*/
CheckSum = CheckSumCalculation((u16 *)TxFrame, ICMP_DATA_START_LOC,
ICMP_DATA_FIELD_LEN );
CheckSum = ~CheckSum;
*(TxFramePtr + ICMP_DATA_CHECKSUM_LOC) = Xil_Htons(CheckSum);
/*
* Transmit the Frame.
*/
XEmacLite_Send(InstancePtr, (u8 *)&TxFrame, ICMP_PKT_SIZE);
}
/**
*
* This function processes the received packet and generates the corresponding
* reply packets.
*
* @param InstancePtr is a pointer to the instance of the EmacLite.
*
* @return None.
*
* @note This function assumes MAC does not strip padding or CRC.
*
******************************************************************************/
static void ProcessRecvFrame(XEmacLite *InstancePtr)
{
u16 *RxFramePtr;
u16 *TxFramePtr;
u16 *TempPtr;
u16 CheckSum;
u32 NextTxBuffBaseAddr;
int Index;
int PacketType = 0;
TxFramePtr = (u16 *)TxFrame;
RxFramePtr = (u16 *)RxFrame;
/*
* Determine the next expected Tx buffer address.
*/
NextTxBuffBaseAddr = XEmacLite_NextTransmitAddr(InstancePtr);
/*
* Check the packet type.
*/
Index = MAC_ADDR_LEN;
TempPtr = (u16 *)LocalMacAddr;
while (Index--) {
if (Xil_Ntohs((*(RxFramePtr + Index)) == BROADCAST_ADDR) &&
(PacketType != MAC_MATCHED_PACKET)) {
PacketType = BROADCAST_PACKET;
} else if (Xil_Ntohs((*(RxFramePtr + Index)) == *(TempPtr + Index)) &&
(PacketType != BROADCAST_PACKET)) {
PacketType = MAC_MATCHED_PACKET;
} else {
PacketType = 0;
break;
}
}
/*
* Process broadcast packet.
*/
if (PacketType == BROADCAST_PACKET) {
/*
* Check for an ARP Packet if so generate a reply.
*/
if (Xil_Ntohs(*(RxFramePtr + ETHER_PROTO_TYPE_LOC)) ==
XEL_ETHER_PROTO_TYPE_ARP) {
/*
* IP address of the local machine.
*/
TempPtr = (u16 *)LocalIpAddr;
/*
* Check destination IP address of the packet with
* local IP address.
*/
if (
((*(RxFramePtr + ARP_REQ_DEST_IP_LOC_1)) == *TempPtr++) &&
((*(RxFramePtr + ARP_REQ_DEST_IP_LOC_2)) == *TempPtr++)) {
/*
* Check ARP packet type(request/reply).
*/
if (Xil_Ntohs(*(RxFramePtr + ARP_REQ_STATUS_LOC)) ==
ARP_REQUEST) {
/*
* Add destination MAC address
* to the reply packet (i.e) source
* address of the received packet.
*/
Index = SRC_MAC_ADDR_LOC;
while (Index < (SRC_MAC_ADDR_LOC +
MAC_ADDR_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Add source (local) MAC address
* to the reply packet.
*/
Index = 0;
TempPtr = (u16 *)LocalMacAddr;
while (Index < MAC_ADDR_LEN) {
*TxFramePtr++ = *TempPtr++;
Index++;
}
/*
* Add Ethernet proto type H/W
* type(10/3MBps),H/W address length and
* protocol address len (i.e)same as in
* the received packet
*/
Index = ETHER_PROTO_TYPE_LOC;
while (Index < (ETHER_PROTO_TYPE_LOC +
ETHER_PROTO_TYPE_LEN +
ARP_HW_TYPE_LEN +
ARP_HW_ADD_LEN
+ ARP_PROTO_ADD_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Add ARP reply status to the reply
* packet.
*/
*TxFramePtr++ = Xil_Htons(ARP_REPLY);
/*
* Add local MAC Address
* to the reply packet.
*/
TempPtr = (u16 *)LocalMacAddr;
Index = 0;
while (Index < MAC_ADDR_LEN) {
*TxFramePtr++ = *TempPtr++;
Index++;
}
/*
* Add local IP Address
* to the reply packet.
*/
TempPtr = (u16 *)LocalIpAddr;
Index = 0;
while (Index < IP_ADDR_LEN) {
*TxFramePtr++ = *TempPtr++ ;
Index++;
}
/*
* Add Destination MAC Address
* to the reply packet from the received
* packet.
*/
Index = SRC_MAC_ADDR_LOC;
while (Index < (SRC_MAC_ADDR_LOC +
MAC_ADDR_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Add Destination IP Address
* to the reply packet.
*/
Index = ARP_REQ_SRC_IP_LOC;
while (Index < (ARP_REQ_SRC_IP_LOC +
IP_ADDR_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Fill zeros as per protocol.
*/
Index = 0;
while (Index < ARP_ZEROS_LEN) {
*TxFramePtr++ = 0x0000;
Index++;
}
/*
* Transmit the Reply Packet.
*/
XEmacLite_Send(InstancePtr,
(u8 *)&TxFrame,
ARP_PACKET_SIZE);
}
}
}
}
/*
* Process packets whose MAC address is matched.
*/
if (PacketType == MAC_MATCHED_PACKET) {
/*
* Check ICMP packet.
*/
if (Xil_Ntohs(*(RxFramePtr + ETHER_PROTO_TYPE_LOC)) ==
XEL_ETHER_PROTO_TYPE_IP) {
/*
* Check the IP header checksum.
*/
CheckSum = CheckSumCalculation(RxFramePtr,
IP_HDR_START_LOC,
IP_HDR_LEN);
/*
* Check the Data field checksum.
*/
if (CheckSum == CORRECT_CKSUM_VALUE) {
CheckSum = CheckSumCalculation(RxFramePtr,
ICMP_DATA_START_LOC,
ICMP_DATA_FIELD_LEN);
if (CheckSum == CORRECT_CKSUM_VALUE) {
/*
* Add destination address
* to the reply packet (i.e)source
* address of the received packet.
*/
Index = SRC_MAC_ADDR_LOC;
while (Index < (SRC_MAC_ADDR_LOC +
MAC_ADDR_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Add local MAC address
* to the reply packet.
*/
Index = 0;
TempPtr = (u16 *)LocalMacAddr;
while (Index < MAC_ADDR_LEN) {
*TxFramePtr++ = *TempPtr++;
Index++;
}
/*
* Add protocol type
* header length and, packet
* length(60 Bytes) to the reply packet.
*/
Index = ETHER_PROTO_TYPE_LOC;
while (Index < (ETHER_PROTO_TYPE_LOC +
ETHER_PROTO_TYPE_LEN +
IP_VERSION_LEN +
IP_PACKET_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Identification field a random number
* which is set to IDENT_FIELD_VALUE.
*/
*TxFramePtr++ = IDENT_FIELD_VALUE;
/*
* Add fragment type, time to live and
* ICM field. It is same as in the
* received packet.
*/
Index = IP_FRAG_FIELD_LOC;
while (Index < (IP_FRAG_FIELD_LOC +
IP_TTL_ICM_LEN +
IP_FRAG_FIELD_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Checksum first set to 0 and
* added in this field later.
*/
*TxFramePtr++ = 0x0000;
/*
* Add Source IP address
*/
Index = 0;
TempPtr = (u16 *)LocalIpAddr;
while (Index < IP_ADDR_LEN) {
*TxFramePtr++ = *TempPtr++;
Index++;
}
/*
* Add Destination IP address.
*/
Index = ICMP_REQ_SRC_IP_LOC;
while (Index < (ICMP_REQ_SRC_IP_LOC +
IP_ADDR_LEN)) {
*TxFramePtr++ =
*(RxFramePtr + Index);
Index++;
}
/*
* Calculate checksum, and
* add it in the appropriate field.
*/
CheckSum = CheckSumCalculation(
(u16 *)TxFrame,
IP_HDR_START_LOC,
IP_HDR_LEN);
CheckSum = ~CheckSum;
*(TxFramePtr - IP_CSUM_LOC_BACK) =
Xil_Htons(CheckSum);
/*
* Echo reply status & checksum.
*/
Index = ICMP_ECHO_FIELD_LOC;
while (Index < (ICMP_ECHO_FIELD_LOC +
ICMP_ECHO_FIELD_LEN)) {
*TxFramePtr++ = 0x0000;
Index++;
}
/*
* Add data to buffer which was
* received from the packet.
*/
Index = ICMP_DATA_LOC;
while (Index < (ICMP_DATA_LOC +
ICMP_DATA_LEN)) {
*TxFramePtr++ =
(*(RxFramePtr + Index));
Index++;
}
/*
* Generate checksum for the data and
* add it in the appropriate field.
*/
CheckSum = CheckSumCalculation(
(u16 *)TxFrame,
ICMP_DATA_START_LOC,
ICMP_DATA_FIELD_LEN);
CheckSum = ~CheckSum;
*(TxFramePtr - ICMP_DATA_CSUM_LOC_BACK)
= Xil_Htons(CheckSum);
/*
* Transmit the frame.
*/
XEmacLite_Send(InstancePtr,
(u8 *)&TxFrame,
ICMP_PACKET_SIZE);
/*
* Increment the number of
* Ping replies sent.
*/
NumOfPingReplies++;
}
}
}
}
}
/**
*
* This function will send a ARP request packet.
*
* @param InstancePtr is a pointer to the instance of the EmacLite.
*
* @return None.
*
* @note None.
*
******************************************************************************/
static void SendArpReqFrame(XEmacLite *InstancePtr)
{
u16 *TempPtr;
u16 *TxFramePtr;
u32 NextTxBuffBaseAddr;
int Index;
TxFramePtr = (u16 *)TxFrame;
/*
* Determine the next expected transmit buffer base address.
*/
NextTxBuffBaseAddr = XEmacLite_NextTransmitAddr(InstancePtr);
/*
* Add broadcast address.
*/
Index = MAC_ADDR_LEN;
while (Index--) {
*TxFramePtr++ = BROADCAST_ADDR;
}
/*
* Add local MAC address.
*/
Index = 0;
TempPtr = (u16 *)LocalMacAddr;
while (Index < MAC_ADDR_LEN) {
*TxFramePtr++ = *(TempPtr + Index);
Index++;
}
/*
* Add
* - Ethernet proto type.
* - Hardware Type
* - Protocol IP Type
* - IP version (IPv6/IPv4)
* - ARP Request
*/
*TxFramePtr++ = Xil_Htons(XEL_ETHER_PROTO_TYPE_ARP);
*TxFramePtr++ = Xil_Htons(HW_TYPE);
*TxFramePtr++ = Xil_Htons(XEL_ETHER_PROTO_TYPE_IP);
*TxFramePtr++ = Xil_Htons(IP_VERSION);
*TxFramePtr++ = Xil_Htons(ARP_REQUEST);
/*
* Add local MAC address.
*/
Index = 0;
TempPtr = (u16 *)LocalMacAddr;
while (Index < MAC_ADDR_LEN) {
*TxFramePtr++ = *(TempPtr + Index);
Index++;
}
/*
* Add local IP address.
*/
Index = 0;
TempPtr = (u16 *)LocalIpAddress;
while (Index < IP_ADDR_LEN) {
*TxFramePtr++ = *(TempPtr + Index);
Index++;
}
/*
* Fills 6 bytes of information with zeros as per protocol.
*/
Index = 0;
while (Index < 3) {
*TxFramePtr++ = 0x0000;
Index++;
}
/*
* Add Destination IP address.
*/
Index = 0;
TempPtr = (u16 *)DestIpAddress;
while (Index < IP_ADDR_LEN) {
*TxFramePtr++ = *(TempPtr + Index);
Index++;
}
/*
* Transmit the Frame.
*/
XEmacLite_Send(InstancePtr, (u8 *)&TxFrame, ARP_REQ_PKT_SIZE);
}