Add draft structs for Message, Header

lib/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "dns_lib"
-version = "0.9.0"
+version = "0.10.0"
 description = "An implementation of the DNS protocol from scratch based on the many DNS RFCs."
 
 rust-version.workspace = true

lib/README.md

@@ -4,4 +4,5 @@ An implementation of the DNS protocol from scratch based on the many DNS RFCs.
 ## RFCs
 ### Work in progress
 - [1034: Domain Names - Concepts and Facilities](https://datatracker.ietf.org/doc/html/rfc1034)
+- [1035: Domain Names - Implementation and Specification](https://datatracker.ietf.org/doc/html/rfc1035)
 

lib/src/lib.rs

@@ -13,6 +13,7 @@
 // limitations under the License.
 
 pub mod domain;
+pub mod message;
 
 pub use domain::{Domain, TryFromError};
 

lib/src/message.rs

@@ -0,0 +1,50 @@
+// Copyright 2024 Matei Bogdan Radu
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// `Message` format used by the DNS protocol.
+///
+/// For more details, see [RFC 1035, Section 4].
+///
+/// [RFC 1035, Section 4]: https://datatracker.ietf.org/doc/html/rfc1035#section-4
+pub struct Message {
+    pub header: Header,
+}
+
+/// `Header` section of a DNS `Message`.
+///
+/// The header section is always present. It includes fields that specify
+/// which of the remaining sections are present, and also specify
+/// whether the message is a query or a response, a standard query or some
+/// other opcode, etc.
+///
+/// For more details, see [RFC 1035, Section 4.1.1].
+///
+/// [RFC 1035, Section 4.1.1]: https://datatracker.ietf.org/doc/html/rfc1035#section-4.1.1
+pub struct Header {
+    pub id: u16,
+
+    pub qr: bool,
+    pub opcode: u8, // Actually 4-bit, prefer a custom type here
+    pub aa: bool,
+    pub tc: bool,
+    pub rd: bool,
+    pub ra: bool,
+    pub z: u8,     // Acutally 3 bits, prefer a custom type here,
+    pub rcode: u8, // Acutally 4 bits, prefer a custom type here,
+
+    pub qdcount: u16,
+    pub ancount: u16,
+    pub nscount: u16,
+    pub arcount: u16,
+}