Stub for libFenrir

Signed-off-by: Luca Fulchir <luca.fulchir@runesauth.com>

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+indent_style = space
+indent_size = 4
+
+[*.md]
+trim_trailing_whitespace = false

Cargo.toml

@@ -1,8 +1,44 @@
 [package]
-name = "libFenrir"
+
+name = "fenrir"
 version = "0.1.0"
 edition = "2021"
+# Fenrir won't be ready for a while,
+# we might as well use async fn in trait, which is nightly
+# remember to update this
+rust-version = "1.67.0"
+homepage   = "https://git.runesauth.com/RunesAuth/libFenrir"
+repository = "https://git.runesauth.com/RunesAuth/libFenrir"
+license = "Apache-2.0"
+keywords = [ "Fenrir", "libFenrir", "authentication" ]
+categories = [ "authentication", "cryptography", "network-programming" ]
+
+# keep this until the PoC works
+publish = false
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[lib]
+
+crate_type = [ "lib", "cdylib", "staticlib" ]
+
 [dependencies]
+
+thiserror = { version = "^1.0" }
+tokio = { version = "^1", features = ["full"] }
+# PERF: todo linux-only, behind "iouring" feature
+#tokio-uring = { version = "^0.4" }
+tracing = { version = "^0.1" }
+
+[profile.dev]
+
+opt-level = 0
+debug = true
+debug-assertions = true
+overflow-checks = true
+lto = false
+panic = 'unwind'
+incremental = true
+codegen-units = 256
+rpath = false
+

flake.nix

@@ -26,10 +26,16 @@
           pkg-config
           exa
           fd
-          (rust-bin.stable.latest.default.override {
+          #(rust-bin.stable.latest.default.override {
+          # go with nightly to have async fn in traits
+          (rust-bin.nightly."2023-02-01".default.override {
             #extensions = [ "rust-src" ];
             #targets = [ "arm-unknown-linux-gnueabihf" ];
           })
+          clippy
+          lld
+          cargo-watch
+          rustfmt
         ];
         shellHook = ''
           # use zsh or other custom shell

rustfmt.toml

@@ -0,0 +1,8 @@
+edition = "2021"
+unstable_features = true
+format_strings = true
+max_width = 80
+# next ones do not work on stable yet
+wrap_comments = true
+comment_width = 80
+

src/config/mod.rs

@@ -0,0 +1,23 @@
+//!
+//! Configuration to initialize the Fenrir networking library
+
+use ::std::{net::SocketAddr, num::NonZeroUsize, option::Option, vec::Vec};
+
+/// Main config for libFenrir
+#[derive(Clone, Debug)]
+pub struct Config {
+    /// number of threads that libFenrir will use
+    pub threads: Option<NonZeroUsize>,
+    /// List of ipv4 or ipv6 UDP inet socket to listen on
+    /// If empty, libFenrir will listen on a random UDP port on `0.0.0.0`
+    pub listen: Vec<SocketAddr>,
+}
+
+impl Default for Config {
+    fn default() -> Self {
+        Config {
+            threads: None,
+            listen: Vec::new(),
+        }
+    }
+}

src/lib.rs

@@ -1,14 +1,81 @@
-pub fn add(left: usize, right: usize) -> usize {
-    left + right
+#![deny(
+    missing_docs,
+    missing_debug_implementations,
+    missing_copy_implementations,
+    trivial_casts,
+    trivial_numeric_casts,
+    unsafe_code,
+    unstable_features,
+    unused_import_braces,
+    unused_qualifications
+)]
+
+//!
+//! libFenrir is the official rust library implementing the Fenrir protocol
+
+use ::std::{
+    io::Result,
+    net::{IpAddr, Ipv4Addr, SocketAddr},
+};
+use ::tokio::{net::UdpSocket, runtime};
+use ::tracing::error;
+
+mod config;
+pub use config::Config;
+
+/// Instance of a fenrir endpoint
+#[allow(missing_copy_implementations, missing_debug_implementations)]
+pub struct Fenrir {
+    /// library Configuration
+    cfg: Config,
+    /// internal runtime
+    rt: ::tokio::runtime::Runtime,
 }
 
-#[cfg(test)]
-mod tests {
-    use super::*;
+/// Initialize a new Fenrir endpoint
+pub fn init(config: &Config) -> Result<Fenrir> {
+    // PERF: linux iouring
+    // PERF: multithread pinning with hwloc2 for topology
+    let f = Fenrir::new(config.clone())?;
+    f.add_listener();
+    Ok(f)
+}
 
-    #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
+impl Fenrir {
+    /// Create a new Fenrir endpoint
+    fn new(config: Config) -> Result<Self> {
+        let mut builder = runtime::Builder::new_multi_thread();
+        if let Some(threads) = config.threads {
+            builder.worker_threads(threads.get());
+        }
+        let rt = match builder.thread_name("libFenrir").build() {
+            Ok(rt) => rt,
+            Err(e) => {
+                ::tracing::error!("Can't initialize: {}", e);
+                return Err(e);
+            }
+        };
+        Ok(Fenrir {
+            cfg: config,
+            rt: rt,
+        })
+    }
+    /// Add an UDP listener
+    fn add_listener(&self) {
+        if self.cfg.listen.len() == 0 {
+            self.rt.spawn(listen_udp(SocketAddr::new(
+                IpAddr::V4(Ipv4Addr::new(0, 0, 0, 0)),
+                0, // 0 means random port
+            )));
+        } else {
+            for sock in self.cfg.listen.iter() {
+                self.rt.spawn(listen_udp(sock.clone()));
+            }
+        }
     }
 }
+/// Add an async udp listener
+async fn listen_udp(sock: SocketAddr) -> Result<()> {
+    UdpSocket::bind(sock).await?;
+    Ok(())
+}