public void freeIP(xbs_nat_entry entry)
{
lock (ip_pool)
{
entry.original_source_ip = null;
entry.original_source_ip_bytes = null;
entry.source_mac = null;
entry.last_change_time = DateTime.Now;
last_update = entry.last_change_time;
CountOfUsedIPs--;
}
}
public xbs_nat_entry requestIP(IPAddress originalIP, PhysicalAddress mac)
{
xbs_nat_entry entry = null;
lock (ip_pool)
{
if (CountOfUsedIPs == ip_pool.Count)
{
return(null);
}
entry = ip_pool.Find(isFreeEntry);
if (entry == null)
{
return(null);
}
entry.original_source_ip = originalIP;
entry.original_source_ip_bytes = originalIP.GetAddressBytes();
entry.source_mac = mac;
entry.last_change_time = DateTime.Now;
last_update = entry.last_change_time;
CountOfUsedIPs++;
}
return(entry);
}
private void replaceDestinationIpWithOriginalIP(ref byte[] data, EthernetPacketType ethernet_packet_type, ref xbs_nat_entry nat_entry)
{
replaceDestinationIP(ref data, ethernet_packet_type, ref nat_entry.original_source_ip_bytes);
}
private void replaceSourceIpWithNATSourceIP( ref byte[] data, EthernetPacketType ethernet_packet_type, ref xbs_nat_entry nat_entry)
{
int offset = (ethernet_packet_type == EthernetPacketType.Arp) ? ARP_HEADER_SOURCE_OFFSET : IP_HEADER_SOURCE_OFFSET;
Buffer.BlockCopy(nat_entry.natted_source_ip_bytes, 0, data, offset, 4);
}
public void freeIP(xbs_nat_entry entry)
{
lock (ip_pool)
{
entry.original_source_ip = null;
entry.original_source_ip_bytes = null;
entry.source_mac = null;
entry.last_change_time = DateTime.Now;
last_update = entry.last_change_time;
CountOfUsedIPs--;
}
}
private bool compare_tmpIP(xbs_nat_entry entry)
{
bool ret = (entry.natted_source_ip.Equals(_tmpIP));
return ret;
}
private bool isFreeEntry(xbs_nat_entry entry)
{
return (entry.source_mac == null);
}
private void replaceDestinationIpWithOriginalIP(ref byte[] data, EthernetPacketType ethernet_packet_type, ref xbs_nat_entry nat_entry)
{
replaceDestinationIP(ref data, ethernet_packet_type, ref nat_entry.original_source_ip_bytes);
}
private void replaceSourceIpWithNATSourceIP(ref byte[] data, EthernetPacketType ethernet_packet_type, ref xbs_nat_entry nat_entry)
{
int offset = (ethernet_packet_type == EthernetPacketType.Arp) ? ARP_HEADER_SOURCE_OFFSET : IP_HEADER_SOURCE_OFFSET;
Buffer.BlockCopy(nat_entry.natted_source_ip_bytes, 0, data, offset, 4);
}
/*
* public EthernetPacketType deNAT_outgoing_packet(ref byte[] data, PhysicalAddress dstMAC, PhysicalAddress srcMAC)
* {
* EthernetPacketType ethernet_packet_type = getEthernetPacketType(ref data);
* if (!isIpOrArpPacket(ethernet_packet_type))
* return ethernet_packet_type;
* xbs_nat_entry nat_entry = null;
* lock (NAT_list)
* {
* if (NAT_list.ContainsKey(dstMAC))
* nat_entry = NAT_list[dstMAC];
* }
*
* if (nat_entry != null)
* {
* replaceDestinationIpWithOriginalIP(ref data, ethernet_packet_type, ref nat_entry);
* updateIPChecksums(ref data);
* }
* return ethernet_packet_type;
* }
*/
public EthernetPacketType deNAT_outgoing_packet_PacketDotNet(ref byte[] data, PhysicalAddress dstMAC, PhysicalAddress srcMAC)
{
EthernetPacket p = (EthernetPacket)EthernetPacket.ParsePacket(LinkLayers.Ethernet, data);
EthernetPacketType ethernet_packet_type = getEthernetPacketType(ref data);
IPv4Packet p_IPV4 = null;
ARPPacket p_ARP = null;
bool packet_changed = false;
if (ethernet_packet_type == EthernetPacketType.IpV4)
{
p_IPV4 = (IPv4Packet)p.PayloadPacket;
}
else if (ethernet_packet_type == EthernetPacketType.Arp)
{
p_ARP = (ARPPacket)p.PayloadPacket;
}
else
{
return(ethernet_packet_type);
}
xbs_nat_entry nat_entry = null;
lock (NAT_list)
{
if (dstMAC.Equals(broadcast_mac))
{
if (p_ARP != null)
{
foreach (xbs_nat_entry ne in NAT_list.Values)
{
if (ne.natted_source_ip.Equals(p_ARP.TargetProtocolAddress))
{
nat_entry = ne;
break;
}
}
}
}
else if (NAT_list.ContainsKey(dstMAC))
{
nat_entry = NAT_list[dstMAC];
}
}
#if DEBUG
if (nat_entry != null)
{
xbs_messages.addDebugMessage("% found device in deNAT list: " + dstMAC + " " + nat_entry.natted_source_ip + "=>" + nat_entry.original_source_ip, xbs_message_sender.NAT);
}
#endif
if (nat_entry != null)
{
if (p_IPV4 != null)
{
p_IPV4.DestinationAddress = nat_entry.original_source_ip;
p_IPV4.UpdateIPChecksum();
if (p_IPV4.Protocol == IPProtocolType.UDP)
{
UdpPacket p_UDP = (UdpPacket)p_IPV4.PayloadPacket;
if (NAT_enablePS3mode)
{
bool ret = PS3_replaceClientAnswer_hostAddr(dstMAC, ref p_UDP, nat_entry.original_source_ip, nat_entry.natted_source_ip);
}
p_UDP.UpdateUDPChecksum();
packet_changed = true;
}
else if (p_IPV4.Protocol == IPProtocolType.TCP)
{
((TcpPacket)p_IPV4.PayloadPacket).UpdateTCPChecksum();
packet_changed = true;
}
}
else if (p_ARP != null)
{
p_ARP.TargetProtocolAddress = nat_entry.original_source_ip;
packet_changed = true;
}
}
if (packet_changed)
{
data = p.BytesHighPerformance.ActualBytes();
}
return((packet_changed) ? ethernet_packet_type : EthernetPacketType.None);
}
private bool compare_tmpIP(xbs_nat_entry entry)
{
bool ret = (entry.natted_source_ip.Equals(_tmpIP));
return(ret);
}
private bool isFreeEntry(xbs_nat_entry entry)
{
return(entry.source_mac == null);
}