Elimited Daemonize dependencyrm-dummy

5 files changed, 117 insertions, 37 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 6d036c1..580c719 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -96,11 +96,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "boxfnonce"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "bumpalo"
 version = "3.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -213,15 +208,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "daemonize"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "boxfnonce 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "digest"
 version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1129,7 +1115,6 @@ dependencies = [
  "clear_on_drop 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "cpuprofiler 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-channel 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "daemonize 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "generic-array 0.12.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1223,7 +1208,6 @@ dependencies = [
 "checksum bitflags 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4f67931368edf3a9a51d29886d245f1c3db2f1ef0dcc9e35ff70341b78c10d23"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 "checksum blake2 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "94cb07b0da6a73955f8fb85d24c466778e70cda767a568229b104f0264089330"
-"checksum boxfnonce 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5988cb1d626264ac94100be357308f29ff7cbdd3b36bda27f450a4ee3f713426"
 "checksum bumpalo 3.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "12ae9db68ad7fac5fe51304d20f016c911539251075a214f8e663babefa35187"
 "checksum byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "e3b5ca7a04898ad4bcd41c90c5285445ff5b791899bb1b0abdd2a2aa791211d7"
 "checksum byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
@@ -1238,7 +1222,6 @@ dependencies = [
 "checksum crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c3c7c73a2d1e9fc0886a08b93e98eb643461230d5f1925e4036204d5f2e261a8"
 "checksum crypto-mac 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4434400df11d95d556bac068ddfedd482915eb18fe8bea89bc80b6e4b1c179e5"
 "checksum curve25519-dalek 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "26778518a7f6cffa1d25a44b602b62b979bd88adb9e99ffec546998cf3404839"
-"checksum daemonize 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "70c24513e34f53b640819f0ac9f705b673fcf4006d7aab8778bee72ebfc89815"
 "checksum digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f3d0c8c8752312f9713efd397ff63acb9f85585afbf179282e720e7704954dd5"
 "checksum env_logger 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)" = "44533bbbb3bb3c1fa17d9f2e4e38bbbaf8396ba82193c4cb1b6445d711445d36"
 "checksum error-chain 0.12.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d371106cc88ffdfb1eabd7111e432da544f16f3e2d7bf1dfe8bf575f1df045cd"
diff --git a/Cargo.toml b/Cargo.toml
index feea486..c626761 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -25,7 +25,6 @@ aead = "^0.2"
 clear_on_drop = "0.2.3"
 env_logger = "0.7"
 num_cpus = "^1.10"
-daemonize = "0.4.1"
 crossbeam-channel = "0.4"
 cpuprofiler = { version = "*", optional = true }
 
diff --git a/netns.sh b/netns.sh
index 54b58c9..d2273a3 100755
--- a/netns.sh
+++ b/netns.sh
@@ -87,6 +87,9 @@ ip0 link set wg1 netns $netns1
 n0 $program wg2
 ip0 link set wg2 netns $netns2
 
+# wait for programs to start
+sleep 0.1
+
 key1="$(pp wg genkey)"
 key2="$(pp wg genkey)"
 pub1="$(pp wg pubkey <<<"$key1")"
@@ -102,6 +105,8 @@ configure_peers() {
     ip2 addr add 192.168.241.2/24 dev wg2
     ip2 addr add fd00::2/24 dev wg2
 
+    n0 wg
+
     n0 wg set wg1 \
         private-key <(echo "$key1") \
         listen-port 10000 \
@@ -120,9 +125,9 @@ configure_peers() {
 
     ip1 link set up dev wg1
     ip2 link set up dev wg2
-    sleep 1
     echo "ready"
 }
+
 configure_peers
 
 tests() {
diff --git a/src/main.rs b/src/main.rs
index bf42706..fb5ac2f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -13,9 +13,9 @@ mod configuration;
 mod platform;
 mod wireguard;
 
-use log;
+mod util;
 
-use daemonize::Daemonize;
+use log;
 
 use std::env;
 use std::process::exit;
@@ -62,14 +62,14 @@ fn main() {
     let mut foreground = false;
     let mut args = env::args();
 
-    args.next(); // skip path (argv[0])
-
+    // skip path (argv[0])
+    args.next();
     for arg in args {
         match arg.as_str() {
             "--foreground" | "-f" => {
                 foreground = true;
             }
-            "--root" => {
+            "--disable-drop-privileges" => {
                 drop_privileges = false;
             }
             dev => name = Some(dev.to_owned()),
@@ -97,16 +97,26 @@ fn main() {
         exit(-3);
     });
 
-    // daemonize
+    // drop privileges
+    if drop_privileges {
+        match util::drop_privileges() {
+            Ok(_) => (),
+            Err(e) => {
+                eprintln!("Failed to drop privileges: {}", e);
+                exit(-4);
+            }
+        }
+    }
+
+    // daemonize to background
     if !foreground {
-        let daemonize = Daemonize::new()
-            .pid_file(format!("/tmp/wireguard-rs-{}.pid", name))
-            .chown_pid_file(true)
-            .working_directory("/tmp")
-            .user("nobody")
-            .group("daemon")
-            .umask(0o777);
-        daemonize.start().expect("Failed to daemonize");
+        match util::daemonize() {
+            Ok(_) => (),
+            Err(e) => {
+                eprintln!("Failed to daemonize: {}", e);
+                exit(-5);
+            }
+        }
     }
 
     // start logging
@@ -114,10 +124,7 @@ fn main() {
         .try_init()
         .expect("Failed to initialize event logger");
 
-    log::info!("starting {} wireguard device", name);
-
-    // drop privileges
-    if drop_privileges {}
+    log::info!("Starting {} WireGuard device.", name);
 
     // start profiler (if enabled)
     #[cfg(feature = "profiler")]
diff --git a/src/util.rs b/src/util.rs
new file mode 100644
index 0000000..dd7a669
--- /dev/null
+++ b/src/util.rs
@@ -0,0 +1,86 @@
+use std::fmt;
+use std::process::exit;
+
+use libc::{c_char, chdir, chroot, fork, getpwnam, getuid, setgid, setsid, setuid, umask};
+
+#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone)]
+pub enum DaemonizeError {
+    Fork,
+    SetSession,
+    SetGroup,
+    SetUser,
+    Chroot,
+    Chdir,
+}
+
+impl fmt::Display for DaemonizeError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            DaemonizeError::Fork => "unable to fork",
+            DaemonizeError::SetSession => "unable to create new process session",
+            DaemonizeError::SetGroup => "unable to set group (drop privileges)",
+            DaemonizeError::SetUser => "unable to set user (drop privileges)",
+            DaemonizeError::Chroot => "unable to enter chroot jail",
+            DaemonizeError::Chdir => "failed to change directory",
+        }
+        .fmt(f)
+    }
+}
+
+fn fork_and_exit() -> Result<(), DaemonizeError> {
+    let pid = unsafe { fork() };
+    if pid < 0 {
+        Err(DaemonizeError::Fork)
+    } else if pid == 0 {
+        Ok(())
+    } else {
+        exit(0);
+    }
+}
+
+pub fn daemonize() -> Result<(), DaemonizeError> {
+    // fork from the original parent
+    fork_and_exit()?;
+
+    // avoid killing the child when this parent dies
+    if unsafe { setsid() } < 0 {
+        return Err(DaemonizeError::SetSession);
+    }
+
+    // fork again to create orphan
+    fork_and_exit()
+}
+
+pub fn drop_privileges() -> Result<(), DaemonizeError> {
+    // retrieve nobody's uid & gid
+    let usr = unsafe { getpwnam("nobody\x00".as_ptr() as *const c_char) };
+    if usr.is_null() {
+        return Err(DaemonizeError::SetGroup);
+    }
+
+    // change root directory
+    let uid = unsafe { getuid() };
+    if uid == 0 && unsafe { chroot("/tmp\x00".as_ptr() as *const c_char) } != 0 {
+        return Err(DaemonizeError::Chroot);
+    }
+
+    // set umask for files
+    unsafe { umask(0) };
+
+    // change directory
+    if unsafe { chdir("/\x00".as_ptr() as *const c_char) } != 0 {
+        return Err(DaemonizeError::Chdir);
+    }
+
+    // set group id to nobody
+    if unsafe { setgid((*usr).pw_gid) } != 0 {
+        return Err(DaemonizeError::SetGroup);
+    }
+
+    // set user id to nobody
+    if unsafe { setuid((*usr).pw_uid) } != 0 {
+        Err(DaemonizeError::SetUser)
+    } else {
+        Ok(())
+    }
+}