feat: fleshed out handling a new connection

Makefile.toml

@@ -37,7 +37,7 @@ args = ["clean"]
 workspace = false
 command = "docker-compose"
 args = ["run", "build", "check", "${@}"]
-watch = { watch = ["nl-sys/src", "pcap-sys/src"] }
+watch = { watch = ["nl-sys/src", "pcap-sys/src", "sparse-05/sparse-05-client/src", "sparse-05/sparse-05-common/src", "sparse-05/sparse-05-server/src"] }
 
 #-----------------------
 # 

pcap-sys/src/lib.rs

@@ -328,7 +328,7 @@ impl<T: Activated> Interface<T> {
 
 struct ListenHandler<'a, F>
 where
-    F: Fn(&Interface<DevListening>, packets::EthernetPkt) -> error::Result<bool>,
+    F: FnMut(&Interface<DevListening>, packets::EthernetPkt) -> error::Result<bool>,
 {
     packet_handler: F,
     break_on_fail: bool,
@@ -344,14 +344,14 @@ impl<T: NotListening> Interface<T> {
         packet_count: i32,
     ) -> (Option<error::Error>, i32)
     where
-        F: Fn(&Interface<DevListening>, packets::EthernetPkt) -> error::Result<bool>,
+        F: FnMut(&Interface<DevListening>, packets::EthernetPkt) -> error::Result<bool>,
     {
         unsafe extern "C" fn cback<F>(
             user: *mut libc::c_void,
             header: *const ffi::PktHeader,
             data: *const u8,
         ) where
-            F: Fn(&Interface<DevListening>, packets::EthernetPkt) -> error::Result<bool>,
+            F: FnMut(&Interface<DevListening>, packets::EthernetPkt) -> error::Result<bool>,
         {
             let info = &mut *(user as *mut ListenHandler<F>);
 

sparse-05/sparse-05-server/src/capabilities.rs

@@ -4,7 +4,7 @@ use sparse_05_common::messages::{Capabilities, TransportType};
 
 const CAP_SETUID: u32 = 1 << 7;
 const CAP_NET_RAW: u32 = 1 << 13;
-const SYS_capget: i64 = 125;
+const SYS_CAPGET: i64 = 125;
 
 #[allow(non_camel_case_types)]
 #[repr(C)]
@@ -41,7 +41,7 @@ fn get_username(uid: u32) -> anyhow::Result<Option<String>> {
     }))
 }
 
-pub fn get_capabilities() -> anyhow::Result<Capabilities> {
+fn get_current_capabilities() -> anyhow::Result<Capabilities> {
     let mut header = cap_user_header_t {
         version: 0x20080522,
         pid: 0,
@@ -52,7 +52,7 @@ pub fn get_capabilities() -> anyhow::Result<Capabilities> {
         inheritable: 0,
     };
     let oscapabilities =
-        unsafe { libc::syscall(SYS_capget, &mut header as *const _, &mut data as *mut _) };
+        unsafe { libc::syscall(SYS_CAPGET, &mut header as *const _, &mut data as *mut _) };
 
     if oscapabilities == -1 {
         return Err(std::io::Error::last_os_error())?;
@@ -79,3 +79,7 @@ pub fn get_capabilities() -> anyhow::Result<Capabilities> {
         transport,
     })
 }
+
+pub fn get_capabilities() -> anyhow::Result<Capabilities> {
+    get_current_capabilities()
+}

sparse-05/sparse-05-server/src/connection.rs

@@ -1,10 +1,22 @@
-use std::sync::mpsc::Sender;
+use std::{net::Ipv4Addr, sync::mpsc::Sender};
 
 use pcap_sys::packets::EthernetPacket;
 
 #[derive(Clone)]
 pub struct ConnectionHandle {}
 
-pub fn spawn_connection_handler(packet_sender: Sender<EthernetPacket>) -> ConnectionHandle {
+impl ConnectionHandle {
+    pub fn handle_packet(&self, packet: EthernetPacket) -> anyhow::Result<()> {
+        Ok(())
+    }
+}
+
+pub enum State {}
+
+pub fn spawn_connection_handler(
+    packet_sender: Sender<EthernetPacket>,
+    connection_packet: EthernetPacket,
+    connection_killer: Sender<(Ipv4Addr, u16)>,
+) -> ConnectionHandle {
     ConnectionHandle {}
 }

sparse-05/sparse-05-server/src/interface.rs

@@ -22,7 +22,7 @@ impl Interface {
                     .find(|eth| eth.starts_with("eth") || eth.starts_with("en"))
                     .ok_or(anyhow!("could not get an ethernet interface"))?;
 
-                let mut interface = loop {
+                let interface = loop {
                     macro_rules! retry {
                         ($e:expr) => {{
                             match $e {
@@ -118,14 +118,14 @@ pub enum InterfaceReceiver {
 }
 
 impl InterfaceReceiver {
-    pub fn listen<F>(&self, f: F) -> anyhow::Result<()>
+    pub fn listen<F>(&self, mut f: F) -> anyhow::Result<()>
     where
-        F: Fn(packets::EthernetPacket) -> anyhow::Result<()>,
+        F: FnMut(packets::EthernetPacket) -> anyhow::Result<()>,
     {
         match self {
             Self::RawUdp(interf) => interf.listen(
                 move |_, packet| {
-                    (f)(packet.to_owned());
+                    let _ = (f)(packet.to_owned());
                     Ok(false)
                 },
                 false,
@@ -153,7 +153,7 @@ impl InterfaceReceiver {
                     &Layer3Packet::IPv4(ip_packet),
                 );
 
-                (f)(ether_packet);
+                let _ = (f)(ether_packet);
             },
         };
 

sparse-05/sparse-05-server/src/main.rs

@@ -1,17 +1,19 @@
 use std::{
     collections::HashMap,
     net::Ipv4Addr,
-    sync::{mpsc::channel, Arc},
+    sync::{mpsc::channel, Arc, Mutex},
     thread,
 };
 
-use anyhow::{anyhow, bail, Context};
+use anyhow::{bail, Context};
 use connection::ConnectionHandle;
 use ed25519_dalek::PublicKey;
 
 use pcap_sys::packets::EthernetPacket;
 use sparse_05_common::CONFIG_SEPARATOR;
 
+use crate::connection::spawn_connection_handler;
+
 mod capabilities;
 mod connection;
 mod interface;
@@ -40,17 +42,56 @@ fn main() -> anyhow::Result<()> {
     let interface = interface::Interface::new(capabilities.transport, port)?;
     let (interface_sender, interface_receiver) = interface.split()?;
 
-    let mut connections: HashMap<(Ipv4Addr, u16), ConnectionHandle> = HashMap::new();
+    let connections: Arc<Mutex<HashMap<(Ipv4Addr, u16), ConnectionHandle>>> =
+        Arc::new(Mutex::new(HashMap::new()));
     let (send_eth_packet, recv_eth_packet) = channel::<EthernetPacket>();
+    let (kill_connection, kill_connection_recv) = channel::<(Ipv4Addr, u16)>();
 
-    {
     thread::spawn(move || loop {
         let Ok(packet) = recv_eth_packet.recv() else { continue };
         if let Err(_) = interface_sender.sendpacket(packet.pkt()) {}
     });
+
+    thread::spawn({
+        let connections = Arc::clone(&connections);
+        move || loop {
+            let Ok(connection) = kill_connection_recv.recv() else { continue };
+            if let Ok(mut e) = connections.lock() {
+                e.remove(&connection);
+            }
+        }
+    });
+
+    interface_receiver.listen(|pkt| {
+        use pcap_sys::packets::*;
+
+        let pkt = pkt.pkt();
+
+        let Layer3Pkt::IPv4Pkt(ip_pkt) = pkt.get_layer3_pkt()?;
+        let Layer4Pkt::UDP(udp_pkt) = ip_pkt.get_layer4_packet()?;
+
+        let connection_handle = &(ip_pkt.dest_ip(), udp_pkt.srcport());
+
+        if let Ok(mut connections) = connections.lock() {
+            let connection = connections.get(connection_handle);
+
+            match connection {
+                None => {
+                    let new_connection = spawn_connection_handler(
+                        send_eth_packet.clone(),
+                        pkt.to_owned(),
+                        kill_connection.clone(),
+                    );
+                    connections.insert(*connection_handle, new_connection);
+                }
+                Some(conn) => {
+                    conn.handle_packet(pkt.to_owned())?;
+                }
+            }
         }
 
-    interface_receiver.listen(move |_| Ok(()))?;
+        Ok(())
+    })?;
 
     Ok(())
 }