支持tap网卡,优化tun网卡配置

switch/src/handle/tap_handler.rs

@@ -0,0 +1,112 @@
+use std::net::Ipv4Addr;
+use std::sync::Arc;
+use std::{io, thread};
+use crossbeam::atomic::AtomicCell;
+use p2p_channel::channel::sender::Sender;
+use packet::arp::arp::ArpPacket;
+use packet::ethernet;
+use packet::ethernet::packet::EthernetPacket;
+use packet::icmp::icmp::IcmpPacket;
+use packet::icmp::Kind;
+use packet::ip::ipv4;
+use packet::ip::ipv4::packet::IpV4Packet;
+use crate::handle::{check_dest, CurrentDeviceInfo};
+use crate::protocol::{MAX_TTL, NetPacket, Protocol, Version};
+use crate::tap_device::{TapReader, TapWriter};
+
+pub fn start(sender: Sender<Ipv4Addr>,
+             tap_reader: TapReader,
+             tap_writer: TapWriter,
+             current_device: Arc<AtomicCell<CurrentDeviceInfo>>, ) {
+    thread::Builder::new().name("tap-handler".into()).spawn(move || {
+        if let Err(e) = start_(sender, tap_reader, tap_writer, current_device) {
+            log::warn!("{:?}",e);
+        }
+    }).unwrap();
+}
+
+fn start_(sender: Sender<Ipv4Addr>,
+          tap_reader: TapReader,
+          tap_writer: TapWriter,
+          current_device: Arc<AtomicCell<CurrentDeviceInfo>>, ) -> io::Result<()> {
+    let mut net_packet = NetPacket::new(vec![0u8; 4 + 8 + 1500]).unwrap();
+    net_packet.set_version(Version::V1);
+    net_packet.set_protocol(Protocol::Ipv4Turn);
+    net_packet.set_transport_protocol(ipv4::protocol::Protocol::Ipv4.into());
+    net_packet.set_ttl(MAX_TTL);
+    let mut buf = [0; 2048];
+    loop {
+        let len = tap_reader.read(&mut buf)?;
+        if len == 0 {
+            continue;
+        }
+        let mut ethernet_packet = EthernetPacket::unchecked(&mut buf[..len]);
+        if let Err(e) = handle(&mut net_packet, &current_device, &tap_writer, &mut ethernet_packet, &sender) {
+            log::error!("tap handle{:?}",e);
+        }
+    }
+}
+
+fn handle(net_packet: &mut NetPacket<Vec<u8>>, current_device: &AtomicCell<CurrentDeviceInfo>, tap_writer: &TapWriter, ethernet_packet: &mut EthernetPacket<&mut [u8]>, sender: &Sender<Ipv4Addr>) -> io::Result<()> {
+    let current_device = current_device.load();
+    match ethernet_packet.protocol() {
+        ethernet::protocol::Protocol::Arp => {
+            let mut out_ethernet_packet = ethernet::packet::EthernetPacket::unchecked(ethernet_packet.buffer.to_vec());
+            let arp_packet = ArpPacket::unchecked(ethernet_packet.payload());
+            let mut out_arp_packet = ArpPacket::unchecked(out_ethernet_packet.payload_mut());
+            let sender_h = arp_packet.sender_hardware_addr();
+            let sender_p = arp_packet.sender_protocol_addr();
+            let target_p = arp_packet.target_protocol_addr();
+            if target_p == &[0, 0, 0, 0] || sender_p == &[0, 0, 0, 0] || target_p == sender_p {
+                return Ok(());
+            }
+            //回复一个虚假的MAC地址
+            out_arp_packet.set_sender_hardware_addr(&[target_p[0], target_p[1], target_p[2], target_p[3], 123, 234]);
+            out_arp_packet.set_sender_protocol_addr(target_p);
+            out_arp_packet.set_target_hardware_addr(sender_h);
+            out_arp_packet.set_target_protocol_addr(sender_p);
+            out_arp_packet.set_op_code(2);
+            out_ethernet_packet.set_source(&[target_p[0], target_p[1], target_p[2], target_p[3], 123, 234]);
+            out_ethernet_packet.set_destination(sender_h);
+
+            tap_writer.write(&out_ethernet_packet.buffer)?;
+        }
+        ethernet::protocol::Protocol::Ipv4 => {
+            // println!("in ethernet_packet {:?}", ethernet_packet);
+            let mut ipv4_packet = IpV4Packet::unchecked(ethernet_packet.payload_mut());
+            let src_ip = ipv4_packet.source_ip();
+            let dest_ip = ipv4_packet.destination_ip();
+            if src_ip != current_device.virtual_ip() || (!check_dest(dest_ip, current_device.virtual_netmask, current_device.virtual_network) && !dest_ip.is_broadcast()) {
+                return Ok(());
+            }
+            if src_ip == dest_ip {
+                if ipv4_packet.protocol() == ipv4::protocol::Protocol::Icmp {
+                    let mut icmp = IcmpPacket::unchecked(ipv4_packet.payload_mut());
+                    if icmp.kind() == Kind::EchoRequest {
+                        icmp.set_kind(Kind::EchoReply);
+                        icmp.update_checksum();
+                        let src = ipv4_packet.source_ip();
+                        ipv4_packet.set_source_ip(ipv4_packet.destination_ip());
+                        ipv4_packet.set_destination_ip(src);
+                        ipv4_packet.update_checksum();
+                        tap_writer.write(ethernet_packet.buffer)?;
+                        return Ok(());
+                    }
+                }
+            }
+            net_packet.set_source(src_ip);
+            net_packet.set_destination(dest_ip);
+            let data_len = ipv4_packet.buffer.len();
+            net_packet.set_payload(ipv4_packet.buffer);
+            //优先发到直连到地址
+            if sender.send_to_id(&net_packet.buffer()[..(12 + data_len)], &dest_ip).is_err() {
+                sender.send_to_addr(&net_packet.buffer()[..(12 + data_len)], current_device.connect_server)?;
+            }
+        }
+        p => {
+            log::warn!("不支持的二层协议：{:?}",p)
+        }
+    }
+    Ok(())
+}
+