RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-28 05:35:06 +00:00
Code Issues Activity Actions

Kernel: Start adding IPv4 support, starting with ICMP echo messages.

Browse source 
This doesn't work correctly yet, but it's getting nice enough to commit.
This commit is contained in:
Andreas Kling 2019-03-12 04:11:20 +01:00
parent d5dbb602b8
commit 5bd9844dd6
6 changed files with 237 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

64
Kernel/NetworkTask.cpp
View file

@ -1,12 +1,18 @@
#include <Kernel/E1000NetworkAdapter.h>
#include <Kernel/EthernetFrameHeader.h>
#include <Kernel/ARPPacket.h>
#include <Kernel/ICMP.h>
#include <Kernel/IPv4Packet.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()
{
@ -35,12 +41,14 @@ void NetworkTask_main()
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:
@ -123,5 +131,61 @@ void handle_arp(const EthernetFrameHeader& eth, int frame_size)
void handle_ipv4(const EthernetFrameHeader& eth, int frame_size)
{
constexpr int minimum_ipv4_frame_size = sizeof(EthernetFrameHeader) + sizeof(IPv4Packet) + sizeof(EthernetFrameCheckSequence);
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 (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)
{
auto& ipv4_packet = *static_cast<const IPv4Packet*>(eth.payload());
auto& icmp_header = *static_cast<const ICMPHeader*>(ipv4_packet.payload());
kprintf("handle_icmp: type=%b, code=%b\n", icmp_header.type(), icmp_header.code());
auto& e1000 = *E1000NetworkAdapter::the();
if (ipv4_packet.destination() == e1000.ipv4_address()) {
// It's for me!
if (icmp_header.type() == ICMPType::EchoRequest) {
auto& request = reinterpret_cast<const ICMPEchoPacket&>(icmp_header);
kprintf("ICMP echo request: id=%u, seq=%u\n", (int)request.identifier, (int)request.sequence_number);
byte* response_buffer = (byte*)kmalloc(ipv4_packet.length());
memset(response_buffer, 0, ipv4_packet.length());
struct [[gnu::packed]] EchoResponse {
IPv4Packet ipv4;
ICMPEchoPacket icmp_echo;
};
auto& response = *(EchoResponse*)response_buffer;
response.ipv4.set_version(4);
response.ipv4.set_internet_header_length(5);
response.ipv4.set_source(e1000.ipv4_address());
response.ipv4.set_destination(ipv4_packet.source());
response.ipv4.set_protocol(IPv4Protocol::ICMP);
response.ipv4.set_length(sizeof(IPv4ICMPPacket));
response.icmp_echo.header.set_type(ICMPType::EchoReply);
response.icmp_echo.header.set_code(0);
response.icmp_echo.identifier = request.identifier;
response.icmp_echo.sequence_number = request.sequence_number;
memcpy(response.icmp_echo.payload, request.payload, ipv4_packet.length() - sizeof(ICMPEchoPacket));
e1000.send_ipv4(eth.source(), &response, ipv4_packet.length());
kfree(response_buffer);
}
}
}