fix: correct and test send and receive corner cases

crates/scion-proto/src/address/scion_address.rs

@@ -167,7 +167,6 @@ macro_rules! scion_address {
             fn from_str(s: &str) -> Result<Self, Self::Err> {
                 s.split_once(',')
                     .and_then(|(ia_str, host_str)| {
-                        println!("{}, {}", ia_str, host_str);
                         ia_str.parse().ok().zip(host_str.parse().ok())
                     })
                     .map(|(isd_asn, host)| Self {isd_asn, host})

crates/scion-proto/src/packet/udp.rs

@@ -19,6 +19,39 @@ pub struct ScionPacketUdp {
     pub datagram: UdpDatagram,
 }
 
+impl ScionPacketUdp {
+    /// Returns the source socket address of the UDP packet.
+    pub fn source(&self) -> Option<SocketAddr> {
+        self.headers
+            .address
+            .source()
+            .map(|scion_addr| SocketAddr::new(scion_addr, self.src_port()))
+    }
+
+    /// Returns the destination socket address of the UDP packet.
+    pub fn destination(&self) -> Option<SocketAddr> {
+        self.headers
+            .address
+            .destination()
+            .map(|scion_addr| SocketAddr::new(scion_addr, self.dst_port()))
+    }
+
+    /// Returns the UDP packet payload.
+    pub fn payload(&self) -> &Bytes {
+        &self.datagram.payload
+    }
+
+    /// Returns the UDP source port
+    pub fn src_port(&self) -> u16 {
+        self.datagram.port.source
+    }
+
+    /// Returns the UDP destination port
+    pub fn dst_port(&self) -> u16 {
+        self.datagram.port.destination
+    }
+}
+
 impl ScionPacketUdp {
     /// Creates a new SCION UDP packet based on the UDP payload
     pub fn new(

crates/scion-proto/src/path.rs

@@ -54,6 +54,16 @@ impl Path {
         }
     }
 
+    /// Returns a path for sending packets within the specified AS.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the AS is a wildcard AS.
+    pub fn local(isd_asn: IsdAsn) -> Self {
+        assert!(!isd_asn.is_wildcard(), "no local path for wildcard AS");
+        Self::empty(ByEndpoint::with_cloned(isd_asn))
+    }
+
     pub fn empty(isd_asn: ByEndpoint<IsdAsn>) -> Self {
         Self {
             dataplane_path: DataplanePath::EmptyPath,