feat: add the reliable-protocol's common header

crates/scion/Cargo.toml

@@ -5,5 +5,6 @@ edition = "2021"
 publish = false
 
 [dependencies]
+bytes = "1.5.0"
 serde = { version = "1.0.188", features = ["derive"] }
 thiserror = "1.0.48"

crates/scion/src/address/host.rs

@@ -45,6 +45,12 @@ impl HostType {
     }
 }
 
+impl From<HostType> for u8 {
+    fn from(value: HostType) -> Self {
+        value as u8
+    }
+}
+
 /// Trait to be implemented by address types that are supported by SCION
 /// as valid AS-host addresses.
 pub trait HostAddress {

crates/scion/src/lib.rs

@@ -1,2 +1,3 @@
 pub mod address;
 pub mod daemon;
+pub mod reliable;

crates/scion/src/reliable.rs

@@ -0,0 +1,6 @@
+mod common_header;
+pub use common_header::DecodeError;
+
+mod wire_utils;
+
+const ADDRESS_TYPE_OCTETS: usize = 1;