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#include <Kernel/E1000NetworkAdapter.h>
#include <Kernel/EthernetFrameHeader.h>
#include <Kernel/ARP.h>
#include <Kernel/ICMP.h>
#include <Kernel/IPv4.h>
#include <Kernel/IPv4Socket.h>
#include <Kernel/Process.h>
#include <Kernel/EtherType.h>
#include <AK/Lock.h>
//#define ETHERNET_DEBUG
//#define IPV4_DEBUG
static void handle_arp(const EthernetFrameHeader&, int frame_size);
static void handle_ipv4(const EthernetFrameHeader&, int frame_size);
static void handle_icmp(const EthernetFrameHeader&, int frame_size);
Lockable<HashMap<IPv4Address, MACAddress>>& arp_table()
{
static Lockable<HashMap<IPv4Address, MACAddress>>* the;
if (!the)
the = new Lockable<HashMap<IPv4Address, MACAddress>>;
return *the;
}
void NetworkTask_main()
{
auto* e1000_ptr = E1000NetworkAdapter::the();
ASSERT(e1000_ptr);
auto& e1000 = *e1000_ptr;
e1000.set_ipv4_address(IPv4Address(192, 168, 5, 2));
kprintf("NetworkTask: Enter main loop.\n");
for (;;) {
auto packet = e1000.dequeue_packet();
if (packet.is_null()) {
sleep(100);
continue;
}
if (packet.size() < (int)(sizeof(EthernetFrameHeader))) {
kprintf("NetworkTask: Packet is too small to be an Ethernet packet! (%d)\n", packet.size());
continue;
}
auto& eth = *(const EthernetFrameHeader*)packet.pointer();
#ifdef ETHERNET_DEBUG
kprintf("NetworkTask: From %s to %s, ether_type=%w, packet_length=%u\n",
eth.source().to_string().characters(),
eth.destination().to_string().characters(),
eth.ether_type(),
packet.size()
);
#endif
switch (eth.ether_type()) {
case EtherType::ARP:
handle_arp(eth, packet.size());
break;
case EtherType::IPv4:
handle_ipv4(eth, packet.size());
break;
}
}
}
void handle_arp(const EthernetFrameHeader& eth, int frame_size)
{
constexpr int minimum_arp_frame_size = sizeof(EthernetFrameHeader) + sizeof(ARPPacket);
if (frame_size < minimum_arp_frame_size) {
kprintf("handle_arp: Frame too small (%d, need %d)\n", frame_size, minimum_arp_frame_size);
return;
}
auto& packet = *static_cast<const ARPPacket*>(eth.payload());
if (packet.hardware_type() != 1 || packet.hardware_address_length() != sizeof(MACAddress)) {
kprintf("handle_arp: Hardware type not ethernet (%w, len=%u)\n",
packet.hardware_type(),
packet.hardware_address_length()
);
return;
}
if (packet.protocol_type() != EtherType::IPv4 || packet.protocol_address_length() != sizeof(IPv4Address)) {
kprintf("handle_arp: Protocol type not IPv4 (%w, len=%u)\n",
packet.hardware_type(),
packet.protocol_address_length()
);
return;
}
#ifdef ARP_DEBUG
kprintf("handle_arp: operation=%w, sender=%s/%s, target=%s/%s\n",
packet.operation(),
packet.sender_hardware_address().to_string().characters(),
packet.sender_protocol_address().to_string().characters(),
packet.target_hardware_address().to_string().characters(),
packet.target_protocol_address().to_string().characters()
);
#endif
if (packet.operation() == ARPOperation::Request) {
// Who has this IP address?
if (auto* adapter = NetworkAdapter::from_ipv4_address(packet.target_protocol_address())) {
// We do!
kprintf("handle_arp: Responding to ARP request for my IPv4 address (%s)\n",
adapter->ipv4_address().to_string().characters());
ARPPacket response;
response.set_operation(ARPOperation::Response);
response.set_target_hardware_address(packet.sender_hardware_address());
response.set_target_protocol_address(packet.sender_protocol_address());
response.set_sender_hardware_address(adapter->mac_address());
response.set_sender_protocol_address(adapter->ipv4_address());
adapter->send(packet.sender_hardware_address(), response);
}
return;
}
if (packet.operation() == ARPOperation::Response) {
// Someone has this IPv4 address. I guess we can try to remember that.
// FIXME: Protect against ARP spamming.
// FIXME: Support static ARP table entries.
LOCKER(arp_table().lock());
arp_table().resource().set(packet.sender_protocol_address(), packet.sender_hardware_address());
kprintf("ARP table (%d entries):\n", arp_table().resource().size());
for (auto& it : arp_table().resource()) {
kprintf("%s :: %s\n", it.value.to_string().characters(), it.key.to_string().characters());
}
}
}
void handle_ipv4(const EthernetFrameHeader& eth, int frame_size)
{
constexpr int minimum_ipv4_frame_size = sizeof(EthernetFrameHeader) + sizeof(IPv4Packet);
if (frame_size < minimum_ipv4_frame_size) {
kprintf("handle_ipv4: Frame too small (%d, need %d)\n", frame_size, minimum_ipv4_frame_size);
return;
}
auto& packet = *static_cast<const IPv4Packet*>(eth.payload());
#ifdef IPV4_DEBUG
kprintf("handle_ipv4: source=%s, target=%s\n",
packet.source().to_string().characters(),
packet.destination().to_string().characters()
);
#endif
switch ((IPv4Protocol)packet.protocol()) {
case IPv4Protocol::ICMP:
return handle_icmp(eth, frame_size);
default:
kprintf("handle_ipv4: Unhandled protocol %u\n", packet.protocol());
break;
}
}
void handle_icmp(const EthernetFrameHeader& eth, int frame_size)
{
(void)frame_size;
auto& ipv4_packet = *static_cast<const IPv4Packet*>(eth.payload());
auto& icmp_header = *static_cast<const ICMPHeader*>(ipv4_packet.payload());
#ifdef ICMP_DEBUG
kprintf("handle_icmp: source=%s, destination=%d type=%b, code=%b\n",
ipv4_packet.source().to_string().characters(),
ipv4_packet.destination().to_string().characters(),
icmp_header.type(),
icmp_header.code()
);
#endif
{
LOCKER(IPv4Socket::all_sockets().lock());
for (RetainPtr<IPv4Socket> socket : IPv4Socket::all_sockets().resource()) {
LOCKER(socket->lock());
if (socket->protocol() != (unsigned)IPv4Protocol::ICMP)
continue;
socket->did_receive(ByteBuffer::copy((const byte*)&ipv4_packet, sizeof(IPv4Packet) + ipv4_packet.payload_size()));
}
}
auto* adapter = NetworkAdapter::from_ipv4_address(ipv4_packet.destination());
if (!adapter)
return;
if (icmp_header.type() == ICMPType::EchoRequest) {
auto& request = reinterpret_cast<const ICMPEchoPacket&>(icmp_header);
kprintf("handle_icmp: EchoRequest from %s: id=%u, seq=%u\n",
ipv4_packet.source().to_string().characters(),
(word)request.identifier,
(word)request.sequence_number
);
size_t icmp_packet_size = ipv4_packet.payload_size();
auto buffer = ByteBuffer::create_zeroed(icmp_packet_size);
auto& response = *(ICMPEchoPacket*)buffer.pointer();
response.header.set_type(ICMPType::EchoReply);
response.header.set_code(0);
response.identifier = request.identifier;
response.sequence_number = request.sequence_number;
if (size_t icmp_payload_size = icmp_packet_size - sizeof(ICMPEchoPacket))
memcpy(response.payload(), request.payload(), icmp_payload_size);
response.header.set_checksum(internet_checksum(&response, icmp_packet_size));
adapter->send_ipv4(eth.source(), ipv4_packet.source(), IPv4Protocol::ICMP, move(buffer));
}
}
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