feat(shadowsocks-rust): logging support syslog (#2044)

Cargo.lock

@@ -976,7 +976,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "39cab71617ae0d63f51a36d69f866391735b51691dbda63cf6f96d042b63efeb"
 dependencies = [
  "libc",
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -1541,7 +1541,7 @@ dependencies = [
  "libc",
  "percent-encoding",
  "pin-project-lite",
- "socket2 0.5.10",
+ "socket2 0.6.1",
  "system-configuration",
  "tokio",
  "tower-service",
@@ -2592,7 +2592,7 @@ dependencies = [
  "quinn-udp",
  "rustc-hash",
  "rustls",
- "socket2 0.5.10",
+ "socket2 0.6.1",
  "thiserror 2.0.17",
  "tokio",
  "tracing",
@@ -2629,9 +2629,9 @@ dependencies = [
  "cfg_aliases",
  "libc",
  "once_cell",
- "socket2 0.5.10",
+ "socket2 0.6.1",
  "tracing",
- "windows-sys 0.52.0",
+ "windows-sys 0.60.2",
 ]
 
 [[package]]
@@ -2904,7 +2904,7 @@ dependencies = [
  "errno",
  "libc",
  "linux-raw-sys",
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -3273,6 +3273,7 @@ dependencies = [
  "shadowsocks-service",
  "snmalloc-rs",
  "sysexits",
+ "syslog-tracing",
  "tcmalloc",
  "thiserror 2.0.17",
  "time",
@@ -3545,6 +3546,17 @@ version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bf9154bb31a0b747e214520c60cb9a842df871bf6a5fea5be4352b59d6c432ab"
 
+[[package]]
+name = "syslog-tracing"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d349bc2df408b4bf656709a29643641cef7f1795d708f88b105c626a8f64f6e4"
+dependencies = [
+ "libc",
+ "tracing-core",
+ "tracing-subscriber",
+]
+
 [[package]]
 name = "system-configuration"
 version = "0.6.1"
@@ -3603,7 +3615,7 @@ dependencies = [
  "getrandom 0.3.3",
  "once_cell",
  "rustix",
- "windows-sys 0.52.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -4274,7 +4286,7 @@ version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2a7b1c03c876122aa43f3020e6c3c3ee5c05081c9a00739faf7503aeba10d22"
 dependencies = [
- "windows-sys 0.48.0",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]

Cargo.toml

@@ -249,6 +249,7 @@ windows-service = { version = "0.8", optional = true }
 
 [target.'cfg(unix)'.dependencies]
 xdg = "3.0"
+syslog-tracing = "0.3"
 
 [target.'cfg(any(target_arch = "x86", target_arch = "x86_64", target_arch = "aarch64"))'.dependencies]
 reqwest = { version = "0.12", features = [

README.md

@@ -913,6 +913,17 @@ Example configuration:
                     // Optional. If set, keeps the last N log files
                     "max_files": 5
                 }
+            },
+            {
+                // Configure a syslog writer, only supported on *nix system
+                "syslog": {
+                    // `level` and `format` can also be set here, if not set, it will use the default values
+
+                    // Optional. Set the "identity" when calling openlog(). Use current service name by default.
+                    "identity": "identity_name",
+                    // Optional. Set the "facility" when calling openlog(). 1 (user-level messages) by default. See RFC5424.
+                    "facility": 1
+                }
             }
         ]
     },

src/config.rs

@@ -198,6 +198,8 @@ pub struct LogFormatConfig {
 pub enum LogWriterConfig {
     Console(LogConsoleWriterConfig),
     File(LogFileWriterConfig),
+    #[cfg(unix)]
+    Syslog(LogSyslogWriterConfig),
 }
 
 /// Console appender configuration for logging
@@ -269,6 +271,25 @@ impl From<LogRotation> for tracing_appender::rolling::Rotation {
     }
 }
 
+/// File appender configuration for logging
+#[cfg(all(feature = "logging", unix))]
+#[derive(Deserialize, Debug, Clone)]
+pub struct LogSyslogWriterConfig {
+    /// Level override
+    #[serde(default)]
+    pub level: Option<u32>,
+    /// Format override
+    #[serde(default)]
+    pub format: LogFormatConfigOverride,
+
+    /// syslog identity, process name by default
+    #[serde(default)]
+    pub identity: Option<String>,
+    /// Facility, 1 (USER) by default
+    #[serde(default)]
+    pub facility: Option<i32>,
+}
+
 /// Runtime mode (Tokio)
 #[derive(Deserialize, Debug, Clone, Copy, Default, Eq, PartialEq)]
 #[serde(rename_all = "snake_case")]

src/logging/tracing.rs

@@ -1,18 +1,21 @@
 //! Logging facilities with tracing
 
-use std::io;
-use std::io::IsTerminal;
+use std::io::{self, IsTerminal};
 
-use time::UtcOffset;
-use time::format_description::well_known::Rfc3339;
+#[cfg(unix)]
+use syslog_tracing::Syslog;
+use time::{UtcOffset, format_description::well_known::Rfc3339};
 use tracing::level_filters::LevelFilter;
 use tracing_appender::rolling::{InitError, RollingFileAppender};
-use tracing_subscriber::fmt::MakeWriter;
-use tracing_subscriber::fmt::time::OffsetTime;
-use tracing_subscriber::layer::SubscriberExt;
-use tracing_subscriber::util::SubscriberInitExt;
-use tracing_subscriber::{EnvFilter, Layer, Registry, fmt};
+use tracing_subscriber::{
+    fmt::{MakeWriter, time::OffsetTime},
+    layer::SubscriberExt,
+    util::SubscriberInitExt,
+    {EnvFilter, Layer, Registry, fmt},
+};
 
+#[cfg(unix)]
+use crate::config::LogSyslogWriterConfig;
 use crate::config::{
     LogConfig, LogConsoleWriterConfig, LogFileWriterConfig, LogFormatConfig, LogFormatConfigOverride, LogWriterConfig,
 };
@@ -38,6 +41,8 @@ impl MakeLayer for LogWriterConfig {
         match self {
             LogWriterConfig::Console(console_config) => console_config.make_layer(bin_name, global),
             LogWriterConfig::File(file_config) => file_config.make_layer(bin_name, global),
+            #[cfg(unix)]
+            LogWriterConfig::Syslog(syslog_config) => syslog_config.make_layer(bin_name, global),
         }
     }
 }
@@ -63,6 +68,17 @@ impl MakeLayer for LogFileWriterConfig {
     }
 }
 
+#[cfg(unix)]
+impl MakeLayer for LogSyslogWriterConfig {
+    fn make_layer(&self, bin_name: &str, global: &LogConfig) -> BoxedLayer {
+        let level = self.level.unwrap_or(global.level);
+        let format = apply_override(&global.format, &self.format);
+
+        let syslog_writer = make_syslog_writer(bin_name, self);
+        make_fmt_layer(bin_name, level, &format, false, syslog_writer)
+    }
+}
+
 /// Boilerplate for configuring a `fmt::Layer` with `level` and `format` for different writers.
 fn make_fmt_layer<W>(bin_name: &str, level: u32, format: &LogFormatConfig, ansi: bool, writer: W) -> BoxedLayer
 where
@@ -162,3 +178,44 @@ fn apply_override(global: &LogFormatConfig, override_config: &LogFormatConfigOve
         without_time: override_config.without_time.unwrap_or(global.without_time),
     }
 }
+
+#[cfg(unix)]
+fn make_syslog_writer(bin_name: &str, config: &LogSyslogWriterConfig) -> Syslog {
+    use std::ffi::CString;
+
+    use syslog_tracing::{Facility, Options};
+
+    let identity = config.identity.as_deref().unwrap_or(bin_name);
+    let facility = match config.facility {
+        None => Facility::default(),
+        Some(f) => match f {
+            1 => Facility::User,
+            2 => Facility::Mail,
+            3 => Facility::Daemon,
+            4 => Facility::Auth,
+            6 => Facility::Lpr,
+            7 => Facility::News,
+            8 => Facility::Uucp,
+            9 => Facility::Cron,
+            10 => Facility::AuthPriv,
+            16 => Facility::Local0,
+            17 => Facility::Local1,
+            18 => Facility::Local2,
+            19 => Facility::Local3,
+            20 => Facility::Local4,
+            21 => Facility::Local5,
+            22 => Facility::Local6,
+            23 => Facility::Local7,
+            _ => panic!("unsupported syslog facility: {}", f),
+        },
+    };
+    let options = Options::default();
+    let identity = CString::new(identity).expect("syslog identity contains null-byte ('\\0')");
+
+    let syslogger = match Syslog::new(identity, options, facility) {
+        Some(l) => l,
+        None => panic!("syslog is already initialized"),
+    };
+
+    syslogger
+}