add udp for ip fragment

auip/src/interface/utils.rs → auip/src/interface/arp.rs

@@ -65,8 +65,3 @@ pub fn build_and_record_arp(
         Ok(Action::NoAction)
     }
 }
-
-pub fn poll_ipv4(bytes: layer3::ipv4::Packet<&[u8]>) -> Result<()> {
-    log::debug!("Receive packet: {}", bytes);
-    Ok(())
-}

auip/src/interface/iface.rs

@@ -3,7 +3,10 @@ use auip_pkt::{
     layer3,
 };
 
-use crate::{interface::utils, AddrsStorage, ArpStorage, Device, InterfaceConfig, Medium, Result};
+use crate::{
+    build_and_record_arp, poll_ipv4, AddrsStorage, ArpStorage, Device, InterfaceConfig, Medium,
+    Result,
+};
 
 use super::action::Action;
 
@@ -89,7 +92,7 @@ where
             let dest_addr = rx_pkt.dest_addr();
 
             if dest_addr != this_mac_addr && dest_addr != layer2::Address::BROADCAST {
-                log::debug!("Mac address mismatch, Drop it.");
+                log::debug!("Mac address {} mismatch, Drop it.", dest_addr);
 
                 return Ok(Action::NoAction);
             }
@@ -141,7 +144,7 @@ where
                     let tpa = pkt.target_protocol_address()?;
                     let sa = rx_pkt.src_addr();
 
-                    return utils::build_and_record_arp(
+                    return build_and_record_arp(
                         sa,
                         sha,
                         spa,
@@ -155,7 +158,7 @@ where
                 layer2::Layer3Protocol::IPv4 => {
                     let pkt = layer3::ipv4::Packet::new_checked(rx_pkt.payload())?;
 
-                    utils::poll_ipv4(pkt)?;
+                    poll_ipv4(pkt)?;
                 }
                 layer2::Layer3Protocol::IPv6 => {}
                 layer2::Layer3Protocol::Unknown(_) => {}
@@ -170,7 +173,7 @@ where
             let ip_pkt = layer3::IpPacket::parse(rx_bytes)?;
 
             match ip_pkt {
-                layer3::IpPacket::IPv4(pkt) => utils::poll_ipv4(pkt)?,
+                layer3::IpPacket::IPv4(pkt) => poll_ipv4(pkt)?,
                 layer3::IpPacket::Ipv6 => {}
             }
         }

auip/src/interface/ipv4.rs

@@ -0,0 +1,39 @@
+use auip_pkt::{layer3, layer4};
+
+use crate::{Result, poll_udp};
+
+pub fn poll_ipv4(pkt: layer3::ipv4::Packet<&[u8]>) -> Result<()> {
+    log::debug!("Receive packet: {}", pkt);
+
+    // Drop ttl is 0.
+    if pkt.ttl() == 0 {
+        return Ok(());
+    }
+
+    // Check is fragment
+    if pkt.dont_frag() {
+        // enter upper layer.
+        let protocol = pkt.protocol();
+
+        let payload = pkt.payload();
+
+        match protocol {
+            layer3::Protocol::Udp => {
+                let pkt = layer4::udp::Packet::new_checked(payload)?;
+
+                poll_udp(pkt)?;
+            }
+            _ => {}
+        }
+    } else {
+        return Ok(());
+    }
+
+    if pkt.more_frags() {
+        // save frag.
+    } else {
+        // complete frag.
+    }
+
+    Ok(())
+}

auip/src/interface/mod.rs

@@ -8,4 +8,11 @@ pub use config::*;
 
 pub(crate) mod action;
 
-pub(crate) mod utils;
+mod arp;
+pub use arp::*;
+
+mod ipv4;
+pub use ipv4::*;
+
+mod udp;
+pub use udp::*;

auip/src/interface/udp.rs

@@ -0,0 +1,8 @@
+use auip_pkt::layer4;
+
+use crate::Result;
+
+pub fn poll_udp(pkt: layer4::udp::Packet<&[u8]>) -> Result<()> {
+    log::debug!("Receive packet: {}", pkt);
+    Ok(())
+}

pkt/src/layer4/udp.rs

@@ -1,3 +1,5 @@
+use core::fmt::{self, Display, Formatter};
+
 use byteorder::{ByteOrder, NetworkEndian};
 
 use crate::{
@@ -34,6 +36,20 @@ impl<T> IntoInner for Packet<T> {
     }
 }
 
+impl<T: AsRef<[u8]>> Display for Packet<T> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        f.write_str("UDP Packet:")?;
+        f.write_fmt(format_args!(
+            "Src port: {}, Dst port: {}, Length: {}",
+            self.src_port(),
+            self.dst_port(),
+            self.len(),
+        ))?;
+
+        Ok(())
+    }
+}
+
 impl<T: AsRef<[u8]>> Packet<T> {
     /// Imbue a raw octet buffer with UDP packet structure.
     pub fn new_unchecked(buffer: T) -> Packet<T> {