1 files changed, 203 insertions, 0 deletions
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..ad57895
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,203 @@
+#[macro_use]
+extern crate arrayref;
+
+use ::std::io;
+use ::std::time::{Duration, SystemTime, Instant};
+
+mod bin;
+mod ip;
+mod proto;
+mod config;
+mod wg;
+
+struct Source {
+    config: config::Source,
+    data: Option<proto::Source>,
+    next_update: Instant,
+    backoff: Option<u32>,
+}
+
+impl Source {
+    fn new(config: config::Source) -> Source {
+        Source {
+            config,
+            data: None,
+            next_update: Instant::now(),
+            backoff: None,
+        }
+    }
+}
+
+pub struct Device {
+    dev: wg::Device,
+    peer_config: config::PeerConfig,
+    update_config: config::UpdateConfig,
+    sources: Vec<Source>,
+    current: wg::Config,
+}
+
+impl Device {
+    pub fn new(c: config::Config) -> Device {
+        Device {
+            dev: wg::Device::new(c.ifname, c.wg_command),
+            peer_config: c.peers,
+            update_config: c.update,
+            sources: c.sources.into_iter().map(Source::new).collect(),
+            current: wg::Config::new(),
+        }
+    }
+
+    fn make_config(&self, ts: SystemTime) -> (wg::Config, Vec<wg::ConfigError>, SystemTime) {
+        let mut cfg = wg::Config::new();
+        let mut next_update = ts + Duration::from_secs(3600);
+        let mut errs = vec![];
+        for src in self.sources.iter() {
+            if let Some(data) = &src.data {
+                let sc = data.next.as_ref().and_then(|next| {
+                    if ts >= next.update_at {
+                        Some(&next.config)
+                    } else {
+                        next_update = next_update.min(next.update_at);
+                        None
+                    }
+                }).unwrap_or(&data.config);
+                for peer in sc.peers.iter() {
+                    cfg.add_peer(&mut errs, &self.peer_config, &src.config, peer);
+                }
+            }
+        }
+        (cfg, errs, next_update)
+    }
+
+    pub fn update(&mut self) -> io::Result<Instant> {
+        let now = Instant::now();
+        let refresh = self.update_config.refresh_period;
+        let after_refresh = now + Duration::from_secs(u64::from(refresh));
+        let mut next_update = after_refresh;
+        for src in self.sources.iter_mut() {
+            if now < src.next_update {
+                next_update = next_update.min(src.next_update);
+                continue;
+            }
+
+            let r = fetch_source(&src.config.url);
+            let r = match r {
+                Ok(r) => {
+                    eprintln!("<6>Updated [{}]", &src.config.url);
+                    src.data = Some(r);
+                    src.backoff = None;
+                    src.next_update = after_refresh;
+                    continue;
+                }
+                Err(r) => r,
+            };
+
+            eprintln!("<3>Failed to update [{}]: {}", &src.config.url, &r);
+
+            let b = src.backoff.unwrap_or(if src.data.is_some() {
+                refresh / 3
+            } else {
+                u32::min(10, refresh / 10)
+            });
+            let b = (b + b / 3).min(refresh);
+            src.backoff = Some(b);
+            src.next_update = now + Duration::from_secs(u64::from(b));
+            next_update = next_update.min(src.next_update);
+        }
+
+        let sysnow = SystemTime::now();
+        let (config, errors, upd_time) = self.make_config(sysnow);
+        let time_to_upd = upd_time.duration_since(sysnow).unwrap_or(Duration::from_secs(0));
+        next_update = next_update.min(now + time_to_upd);
+
+        if config != self.current {
+            eprintln!("<5>Applying configuration update");
+            for err in errors.iter() {
+                eprintln!("<{}>{}", if err.important { '4' } else { '5' }, err);
+            }
+            self.dev.apply_diff(&self.current, &config)?;
+            self.current = config;
+        }
+        eprintln!("<6>Next configuration update after {:?}", time_to_upd);
+
+        Ok(next_update)
+    }
+}
+
+fn fetch_source(url: &str) -> io::Result<proto::Source> {
+    use ::curl::easy::Easy;
+
+    let mut res = Vec::<u8>::new();
+
+    {
+        let mut req = Easy::new();
+        req.url(url)?;
+
+        {
+            let mut tr = req.transfer();
+            tr.write_function(|data| {
+                res.extend_from_slice(data);
+                Ok(data.len())
+            })?;
+            tr.perform()?;
+        }
+
+        let code = req.response_code()?;
+        if code != 0 && code != 200 {
+            return Err(io::Error::new(io::ErrorKind::Other, format!("HTTP error {}", code)));
+        }
+    }
+
+    let mut de = serde_json::Deserializer::from_slice(&res);
+    let r = serde::Deserialize::deserialize(&mut de)?;
+    Ok(r)
+}
+
+fn load_config(path: &str) -> io::Result<config::Config> {
+    use std::fs;
+    use ::serde_json;
+
+    let config_file = fs::File::open(path)?;
+    let rd = io::BufReader::new(config_file);
+    let mut de = serde_json::Deserializer::from_reader(rd);
+    Ok(serde::Deserialize::deserialize(&mut de)?)
+}
+
+fn main() {
+    use ::std::{env, thread, process};
+
+    let args: Vec<String> = env::args().into_iter().collect();
+    if args.len() != 2 {
+        let arg0 = if args.len() >= 1 {
+            &args[0]
+        } else {
+            "wgconf"
+        };
+        eprintln!("<1>Usage:");
+        eprintln!("<1>    {} CONFIG", arg0);
+        process::exit(1);
+    }
+
+    let config = match load_config(&args[1]) {
+        Ok(c) => c,
+        Err(e) => {
+            eprintln!("<1>Failed to load config: {}", e);
+            process::exit(1);
+        }
+    };
+
+    let mut dev = Device::new(config);
+    loop {
+        let tm = match dev.update() {
+            Ok(t) => t,
+            Err(e) => {
+                eprintln!("<1>{}", e);
+                process::exit(1);
+            }
+        };
+        let now = Instant::now();
+        let sleep = tm.duration_since(now);
+        println!("Sleeping for {:?}", sleep);
+        thread::sleep(sleep);
+    }
+}