impl hostname ding; remove redb (deemed inefficient overkill)

we are not planning to be web-scale(tm) anyway

4 files changed, 211 insertions, 67 deletions

diff --git a/Cargo.lock b/Cargo.lock
index ddc7d53..f3be1b1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -67,6 +67,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b3d1d046238990b9cf5bcde22a3fb3584ee5cf65fb2765f454ed428c7a0063da"
 
 [[package]]
+name = "atomic-write-file"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cbf54d4588732bdfc5ebc3eb9f74f20e027112fc31de412fc7ff0cd1c6896dae"
+dependencies = [
+ "nix 0.28.0",
+ "rand",
+]
+
+[[package]]
 name = "autocfg"
 version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -109,6 +119,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
+name = "cfg_aliases"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fd16c4719339c4530435d38e511904438d07cce7950afa3718a84ac36c10e89e"
+
+[[package]]
 name = "clap"
 version = "4.5.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -169,7 +185,7 @@ dependencies = [
  "netlink-packet-utils",
  "netlink-packet-wireguard",
  "netlink-sys",
- "nix",
+ "nix 0.27.1",
  "serde",
  "thiserror",
 ]
@@ -198,6 +214,17 @@ dependencies = [
 ]
 
 [[package]]
+name = "getrandom"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c4567c8db10ae91089c99af84c68c38da3ec2f087c3f82960bcdbf3656b6f4d7"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+]
+
+[[package]]
 name = "heck"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -252,11 +279,11 @@ dependencies = [
 name = "mäsch"
 version = "0.1.0"
 dependencies = [
+ "atomic-write-file",
  "clap",
  "defguard_wireguard_rs",
  "env_logger",
  "log",
- "redb",
  "serde",
  "serde_json",
  "thiserror",
@@ -350,12 +377,33 @@ dependencies = [
 ]
 
 [[package]]
+name = "nix"
+version = "0.28.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ab2156c4fce2f8df6c499cc1c763e4394b7482525bf2a9701c9d79d215f519e4"
+dependencies = [
+ "bitflags 2.6.0",
+ "cfg-if",
+ "cfg_aliases",
+ "libc",
+]
+
+[[package]]
 name = "paste"
 version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 
 [[package]]
+name = "ppv-lite86"
+version = "0.2.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77957b295656769bb8ad2b6a6b09d897d94f05c41b069aede1fcdaa675eaea04"
+dependencies = [
+ "zerocopy",
+]
+
+[[package]]
 name = "proc-macro2"
 version = "1.0.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -374,12 +422,33 @@ dependencies = [
 ]
 
 [[package]]
-name = "redb"
-version = "2.1.1"
+name = "rand"
+version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a6dd20d3cdeb9c7d2366a0b16b93b35b75aec15309fbeb7ce477138c9f68c8c0"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
 dependencies = [
  "libc",
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom",
 ]
 
 [[package]]
@@ -499,6 +568,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
 
 [[package]]
+name = "wasi"
+version = "0.11.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
+
+[[package]]
 name = "windows-sys"
 version = "0.52.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -576,3 +651,24 @@ name = "xdg"
 version = "2.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "213b7324336b53d2414b2db8537e56544d981803139155afa84f76eeebb7a546"
+
+[[package]]
+name = "zerocopy"
+version = "0.7.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
+dependencies = [
+ "byteorder",
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.7.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
diff --git a/Cargo.toml b/Cargo.toml
index 0114aeb..7cb0994 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,12 +4,12 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-redb = "2"
-serde = { version = "1", features = ["derive"] }
-serde_json = "1"
-xdg = "2"
+atomic-write-file = "0"
+clap = { version = "4.5.13", features = ["derive"] }
+defguard_wireguard_rs = "0"
 env_logger = "0"
 log = "0"
+serde_json = "1"
+serde = { version = "1", features = ["derive"] }
 thiserror = "1"
-clap = { version = "4.5.13", features = ["derive"] }
-defguard_wireguard_rs = "0"
+xdg = "2"
diff --git a/src/daemon.rs b/src/daemon.rs
index 2c73d6c..1c746fd 100644
--- a/src/daemon.rs
+++ b/src/daemon.rs
@@ -1,9 +1,12 @@
+use atomic_write_file::AtomicWriteFile;
 use core::net::SocketAddr;
 use defguard_wireguard_rs::{host::Peer, InterfaceConfiguration, WGApi, WireguardInterfaceApi};
-use defguard_wireguard_rs::{key::Key as WgKey, net::IpAddrMask};
-use log::{info, trace, warn};
-use redb::{Database, Error, Key, Range, ReadableTable, TableDefinition, TypeName, Value};
+use defguard_wireguard_rs::{key::Key, net::IpAddrMask};
+use log::{info, warn};
 use serde::{Deserialize, Serialize};
+use std::collections::BTreeSet;
+use std::fs::File;
+use std::io::{ErrorKind, Read, Write};
 use std::net::{TcpListener, ToSocketAddrs};
 use thiserror::Error;
 use xdg::BaseDirectories;
@@ -18,15 +21,6 @@ pub enum DaemonError {
     #[error("{0}")]
     XdgBase(#[from] xdg::BaseDirectoriesError),
 
-    #[error("{0}")]
-    DbOpen(#[from] redb::DatabaseError),
-    #[error("{0}")]
-    DbTrans(#[from] redb::TransactionError),
-    #[error("{0}")]
-    DbTable(#[from] redb::TableError),
-    #[error("{0}")]
-    DbStorage(#[from] redb::StorageError),
-
     // TODO hier wärs nett zu unterscheiden was decoded wurde
     #[error("{0}")]
     Decoding(#[from] serde_json::Error),
@@ -44,13 +38,12 @@ enum Endpoint {
 // subset of defguard_wireguard_rs::host::Peer, with hostname added
 #[derive(Serialize, Deserialize)]
 struct PeerConfig {
-    pubkey: WgKey,
-    psk: Option<WgKey>,
-    hostname: Option<String>,
-    // if false: the hostname is kept around for sharing, but we personally do not use it
-    use_hostname: bool,
+    pubkey: Key,
+    psk: Option<Key>,
+    ips: Vec<(IpAddrMask, Option<String>)>,
+    // if false: the hostnames are kept around for sharing, but we personally do not use them
+    use_hostnames: bool,
     endpoint: Option<Endpoint>,
-    ips: Vec<IpAddrMask>,
 }
 
 fn default_wg_port() -> u16 {
@@ -58,7 +51,8 @@ fn default_wg_port() -> u16 {
 }
 
 #[derive(Serialize, Deserialize)]
-struct InterfaceConfig {
+struct Network {
+    name: String,
     privkey: String,
 
     // this really should be a different type, but this is what defguard takes...
@@ -70,50 +64,66 @@ struct InterfaceConfig {
     peers: Vec<PeerConfig>,
 }
 
-// NOTE das ist ne dumme idee gewesen... nen peer hinzufügen braucht jz nen kompletten reserialize
-const NETWORKS: TableDefinition<&str, /* InterfaceConfig */ &[u8]> =
-    TableDefinition::new("networks");
+#[derive(Serialize, Deserialize, Default)]
+struct Config {
+    networks: Vec<Network>,
+}
 
 pub fn daemon() -> Result<(), DaemonError> {
-    let db_path = BaseDirectories::with_prefix("mäsch")?.place_state_file("daemon-db")?;
-    let db = Database::create(db_path)?;
-    info!("opened db");
-
-    let networks: Vec<(String, InterfaceConfig)> = match db.begin_read()?.open_table(NETWORKS) {
-        Err(redb::TableError::TableDoesNotExist(_)) => vec![],
-        Ok(tbl) => tbl
-            .iter()?
-            .map(|kv_result| {
-                let (access_key, access_val) = kv_result?;
-                Ok((
-                    access_key.value().to_owned(),
-                    serde_json::from_slice(access_val.value())?,
-                ))
-            })
-            .collect::<Result<_, DaemonError>>()?,
-        Err(e) => Err(e)?,
+    let config_path = BaseDirectories::with_prefix("mäsch")?.place_state_file("daemon.json")?;
+    let config: Config = match File::open(config_path) {
+        Ok(f) => serde_json::from_reader(f)?,
+        Err(e) => match e.kind() {
+            ErrorKind::NotFound => Config::default(),
+            _ => Err(e)?,
+        },
     };
+    info!("read config");
 
-    //let networks = vec![("kek".to_string(), InterfaceConfig {
+    //let networks = vec![Network {
+    //    name: "kek".to_string(),
     //    privkey: "OK9WQudPVO5rXxcdxdtTzRmJzVu+KuqLMstYsZd8mWE=".to_string(),
     //    address: "1.2.3.4".to_string(),
     //    listen_port: 5221,
     //    peers: vec![PeerConfig {
-    //        pubkey: WgKey::from_str("Osrxi/bRVK+FQit7YMbIgSaOWmRDOZQoh/7ddV4eEE8=").unwrap(),
-    //        psk: Some(WgKey::from_str("wFiG3II9ivYBn+xjLGChC0PjNlbOibZ1K6pmspPD0Hg=").unwrap()),
-    //        hostname: Some("blah.blob".to_string()),
-    //        use_hostname: false,
+    //        pubkey: Key::from_str("Osrxi/bRVK+FQit7YMbIgSaOWmRDOZQoh/7ddV4eEE8=").unwrap(),
+    //        psk: Some(Key::from_str("wFiG3II9ivYBn+xjLGChC0PjNlbOibZ1K6pmspPD0Hg=").unwrap()),
+    //        use_hostnames: true,
     //        endpoint: Some(Endpoint::Domain("alex.69owo.de".to_string(), 12456)),
-    //        ips: vec![IpAddrMask::from_str("5.4.3.2/24").unwrap()],
+    //        ips: vec![(IpAddrMask::from_str("5.4.3.2/24").unwrap(), Some("blah.blub".to_owned()))],
     //    }],
-    //})];
+    //}];
 
     // TODO call wg.remove_interface on program exit using a drop impl on an 'Interface' struct
-    // containing the InterfaceConfig and WGApi
-    // TODO possibly add hostnames to /etc/hosts
-    for (name, intr) in networks {
-        let wg = WGApi::new(name.clone(), false)?;
-        let defguard_peers = intr
+    // containing the Network and WGApi
+
+    let mut hostfile = match File::open("/etc/hosts") {
+        Ok(mut f) => {
+            let mut r = String::new();
+            f.read_to_string(&mut r)?;
+
+            let seen_hostnames: BTreeSet<String> = r
+                .lines()
+                .map(|l| {
+                    l.split_whitespace()
+                        .take_while(|dom| dom.chars().next().unwrap() != '#')
+                        .skip(1)
+                })
+                .flatten()
+                .map(|dom| dom.to_owned())
+                .collect();
+
+            Some((r, seen_hostnames))
+        }
+        Err(e) => {
+            warn!("failed to read /etc/hosts: {e}");
+            None
+        }
+    };
+
+    for nw in config.networks {
+        let wg = WGApi::new(nw.name.clone(), false)?;
+        let defguard_peers = nw
             .peers
             .iter()
             .map(|p| Peer {
@@ -136,18 +146,54 @@ pub fn daemon() -> Result<(), DaemonError> {
                 tx_bytes: 0,
                 rx_bytes: 0,
                 persistent_keepalive_interval: None,
-                allowed_ips: p.ips.clone(),
+                allowed_ips: p.ips.iter().map(|(ip_mask, _)| ip_mask.clone()).collect(),
             })
             .collect();
         wg.create_interface()?;
         wg.configure_interface(&InterfaceConfiguration {
-            name,
-            prvkey: intr.privkey,
-            address: intr.address,
-            port: intr.listen_port as u32,
+            name: nw.name.clone(),
+            prvkey: nw.privkey,
+            address: nw.address,
+            port: nw.listen_port as u32,
             peers: defguard_peers,
         })?;
+
+        if let Some((hosts_str, hosts)) = &mut hostfile {
+            nw.peers
+                .iter()
+                .map(|peer| {
+                    if peer.use_hostnames {
+                        peer.ips
+                            .iter()
+                            .map(|(mask, may_dom)| {
+                                if let Some(dom) = may_dom
+                                    && hosts.insert(dom.clone())
+                                {
+                                    hosts_str.push_str(&format!("{}", mask.ip));
+                                    hosts_str.push('\t');
+                                    hosts_str.push_str(&dom);
+                                    hosts_str.push('\n');
+                                }
+                            })
+                            .count();
+                    }
+                })
+                .count();
+        }
+
+        info!("loaded configuration for {0}", nw.name);
     }
+    info!("loaded all existing configurations");
+
+    if let Some((hosts_str, _)) = &hostfile {
+        info!("proposed next hosts file: {hosts_str}");
+
+        let mut f = AtomicWriteFile::open("/etc/hosts")?;
+        f.write(hosts_str.as_bytes())?;
+        f.commit();
+    }
+
+    // TODO open dbus & network interfaces
 
     Ok(())
 }
diff --git a/src/main.rs b/src/main.rs
index 6bc049b..d85da33 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,5 @@
+#![feature(let_chains)]
+
 pub mod daemon;
 
 use clap::{Parser, Subcommand};