RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-28 16:55:09 +00:00
Code Issues Activity Actions

Kernel: Add simple ARP routing layer

Browse source 
This replaces the previous placeholder routing layer with a real one!
It's still very primitive, doesn't deal with things like timeouts very
well, and will probably need several more iterations to support more
normal networking things.

I haven't confirmed that this works with anything other than the QEMU
user networking layer, but I suspect that's what nearly everybody is
using at this point, so that's the important target to keep working.
This commit is contained in:
Conrad Pankoff 2019-08-28 21:58:01 +10:00 • committed by Andreas Kling
parent 626e176cab
commit 6d1418aa7a
6 changed files with 146 additions and 47 deletions
Download patch file Download diff file Expand all files Collapse all files

126
Kernel/Net/Routing.cpp
View file

@ -1,10 +1,124 @@
#include <Kernel/Net/LoopbackAdapter.h>
#include <Kernel/Net/Routing.h>
#include <Kernel/Thread.h>
WeakPtr<NetworkAdapter> adapter_for_route_to(const IPv4Address& ipv4_address)
//#define ROUTING_DEBUG
Lockable<HashMap<IPv4Address, MACAddress>>& arp_table()
{
// FIXME: Have an actual routing table.
if (ipv4_address == IPv4Address(127, 0, 0, 1))
return LoopbackAdapter::the().make_weak_ptr();
return NetworkAdapter::from_ipv4_address(IPv4Address(192, 168, 5, 2));
static Lockable<HashMap<IPv4Address, MACAddress>>* the;
if (!the)
the = new Lockable<HashMap<IPv4Address, MACAddress>>;
return *the;
}
RoutingDecision route_to(const IPv4Address& target, const IPv4Address& source)
{
auto target_addr = target.to_u32();
auto source_addr = source.to_u32();
WeakPtr<NetworkAdapter> local_adapter = nullptr;
WeakPtr<NetworkAdapter> gateway_adapter = nullptr;
NetworkAdapter::for_each([source_addr, &target_addr, &local_adapter, &gateway_adapter](auto& adapter) {
auto adapter_addr = adapter.ipv4_address().to_u32();
auto adapter_mask = adapter.ipv4_netmask().to_u32();
if (source_addr != 0 && source_addr != adapter_addr)
return;
if ((target_addr & adapter_mask) == (adapter_addr & adapter_mask))
local_adapter = adapter.make_weak_ptr();
if (adapter.ipv4_gateway().to_u32() != 0)
gateway_adapter = adapter.make_weak_ptr();
});
if (!local_adapter && !gateway_adapter) {
#ifdef ROUTING_DEBUG
kprintf("Routing: Couldn't find a suitable adapter for route to %s\n",
target.to_string().characters());
#endif
return { nullptr, {} };
}
WeakPtr<NetworkAdapter> adapter = nullptr;
IPv4Address next_hop_ip;
if (local_adapter) {
#ifdef ROUTING_DEBUG
kprintf("Routing: Got adapter for route (direct): %s (%s/%s) for %s\n",
local_adapter->name().characters(),
local_adapter->ipv4_address().to_string().characters(),
local_adapter->ipv4_netmask().to_string().characters(),
target.to_string().characters());
#endif
adapter = local_adapter;
next_hop_ip = target;
} else if (gateway_adapter) {
#ifdef ROUTING_DEBUG
kprintf("Routing: Got adapter for route (using gateway %s): %s (%s/%s) for %s\n",
gateway_adapter->ipv4_gateway().to_string().characters(),
gateway_adapter->name().characters(),
gateway_adapter->ipv4_address().to_string().characters(),
gateway_adapter->ipv4_netmask().to_string().characters(),
target.to_string().characters());
#endif
adapter = gateway_adapter;
next_hop_ip = gateway_adapter->ipv4_gateway();
} else {
return { nullptr, {} };
}
{
LOCKER(arp_table().lock());
auto addr = arp_table().resource().get(next_hop_ip);
if (addr.has_value()) {
#ifdef ROUTING_DEBUG
kprintf("Routing: Using cached ARP entry for %s (%s)\n",
next_hop_ip.to_string().characters(),
addr.value().to_string().characters());
#endif
return { adapter, addr.value() };
}
}
#ifdef ROUTING_DEBUG
kprintf("Routing: Sending ARP request via adapter %s for IPv4 address %s\n",
adapter->name().characters(),
next_hop_ip.to_string().characters());
#endif
ARPPacket request;
request.set_operation(ARPOperation::Request);
request.set_target_hardware_address({ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff });
request.set_target_protocol_address(next_hop_ip);
request.set_sender_hardware_address(adapter->mac_address());
request.set_sender_protocol_address(adapter->ipv4_address());
adapter->send({ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }, request);
(void)current->block_until("Routing (ARP)", [next_hop_ip] {
return arp_table().resource().get(next_hop_ip).has_value();
});
{
LOCKER(arp_table().lock());
auto addr = arp_table().resource().get(next_hop_ip);
if (addr.has_value()) {
#ifdef ROUTING_DEBUG
kprintf("Routing: Got ARP response using adapter %s for %s (%s)\n",
adapter->name().characters(),
next_hop_ip.to_string().characters(),
addr.value().to_string().characters());
#endif
return { adapter, addr.value() };
}
}
#ifdef ROUTING_DEBUG
kprintf("Routing: Couldn't find route using adapter %s for %s\n",
adapter->name().characters(),
target.to_string().characters());
#endif
return { nullptr, {} };
}