fix: ensure tcp keep-alive packets are sent

crates/rproxy/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rproxy"
-version = "0.0.9"
+version = "0.0.10"
 edition = "2024"
 default-run = "rproxy"
 
@@ -40,24 +40,27 @@ futures-core = "0.3.31"
 hex = "0.4.3"
 http = "1.3.1"
 humantime = "2.2.0"
+libc = "0.2.177"
 moka = { version = "0.12.11", features = ["sync"] }
 op-alloy-consensus = "0.20.0"
 parking_lot = "0.12.4"
 pin-project = "1.1.10"
 pnet = "0.35.0"
 prometheus-client = { git = "https://github.com/0x416e746f6e/client_rust.git", branch = "nested-labels"}
 rand = { version = "0.9.2", optional = true }
+rlimit = "0.10.2"
 rustc-hash = "2.1.1"
 rustls = "0.23.32"
 rustls-pemfile = "2.2.0"
 scc = "3.0.2"
 serde = { version = "1.0.219", features = ["derive"] }
 serde_json = "1.0.143"
 socket2 = "0.6.0"
+sysctl = "0.7.1"
 thiserror = "2.0.16"
 time = { version = "0.3.43", features = ["formatting"] }
 tokio = { version = "1.47.1", features = ["macros", "rt", "rt-multi-thread", "signal"] }
-tokio-tungstenite = "0.27.0"
+tokio-tungstenite = {version = "0.27.0", features = ["rustls-tls-native-roots"] }
 tokio-util = "0.7.16"
 tracing = { version = "0.1.41", features = ["valuable"] }
 tracing-subscriber = { version = "0.3.20", features = ["env-filter", "json", "valuable"] }

crates/rproxy/src/config.rs

@@ -1,7 +1,9 @@
 use std::{process, sync::LazyLock};
 
 use clap::Parser;
+use sysctl::Sysctl;
 use thiserror::Error;
+use x509_parser::asn1_rs::ToStatic;
 
 use crate::server::{
     config::{ConfigLogging, ConfigLoggingError, ConfigMetrics, ConfigMetricsError},
@@ -26,6 +28,72 @@ pub(crate) static PARALLELISM: LazyLock<usize> =
 
 pub(crate) static PARALLELISM_STRING: LazyLock<String> = LazyLock::new(|| PARALLELISM.to_string());
 
+pub(crate) static TCP_KEEPALIVE_INTERVAL: LazyLock<libc::c_int> = LazyLock::new(|| {
+    #[cfg(target_os = "linux")]
+    {
+        let mut res: libc::c_int = 75;
+        if let Ok(ctl) = sysctl::Ctl::new("net.ipv4.tcp_keepalive_intvl") &&
+            let Ok(value) = ctl.value() &&
+            let Ok(value) = value.into_int()
+        {
+            res = value
+        }
+        return res;
+    }
+
+    #[cfg(target_os = "macos")]
+    {
+        let mut res: libc::c_int = 75000;
+        if let Ok(ctl) = sysctl::Ctl::new("net.inet.tcp.keepintvl") &&
+            let Ok(value) = ctl.value() &&
+            let Ok(value) = value.into_int()
+        {
+            res = value / 1000 // millis on macos
+        }
+
+        return res;
+    }
+
+    #[allow(unreachable_code)]
+    75
+});
+
+pub(crate) static TCP_KEEPALIVE_INTERVAL_STRING: LazyLock<String> =
+    LazyLock::new(|| format!("{}s", TCP_KEEPALIVE_INTERVAL.to_static()));
+
+pub(crate) static TCP_KEEPALIVE_PROBES: LazyLock<libc::c_int> = LazyLock::new(|| {
+    #[cfg(target_os = "linux")]
+    {
+        let mut res: libc::c_int = 9;
+        if let Ok(ctl) = sysctl::Ctl::new("net.ipv4.tcp_keepalive_probes") &&
+            let Ok(value) = ctl.value() &&
+            let Ok(value) = value.into_int()
+        {
+            res = value
+        }
+        return res;
+    }
+
+    #[cfg(target_os = "macos")]
+    {
+        let mut res: libc::c_int = 8;
+        if let Ok(ctl) = sysctl::Ctl::new("net.inet.tcp.keepcnt") &&
+            let Ok(value) = ctl.value() &&
+            let Ok(value) = value.into_int()
+        {
+            res = value
+        }
+
+        return res;
+    }
+
+    #[allow(unreachable_code)]
+    8
+});
+
+pub(crate) static TCP_KEEPALIVE_PROBES_STRING: LazyLock<String> =
+    LazyLock::new(|| TCP_KEEPALIVE_PROBES.to_string());
+
 // Config --------------------------------------------------------------
 
 #[derive(Clone, Parser)]