feat(client): add macOS system proxy support for Matcher (#189)

Author: seanmonstar

Cargo.toml

@@ -26,13 +26,13 @@ http = "1.0"
 http-body = "1.0.0"
 hyper = "1.6.0"
 ipnet = { version = "2.9", optional = true }
+libc = { version = "0.2", optional = true }
 percent-encoding = { version = "2.3", optional = true }
 pin-project-lite = "0.2.4"
 socket2 = { version = "0.5.9", optional = true, features = ["all"] }
 tracing = { version = "0.1", default-features = false, features = ["std"], optional = true }
 tokio = { version = "1", optional = true, default-features = false  }
 tower-service = { version = "0.3", optional = true }
-libc = { version = "0.2", optional = true }
 
 [dev-dependencies]
 hyper = { version = "1.4.0", features = ["full"] }
@@ -45,6 +45,9 @@ pretty_env_logger = "0.5"
 [target.'cfg(any(target_os = "linux", target_os = "macos"))'.dev-dependencies]
 pnet_datalink = "0.35.0"
 
+[target.'cfg(target_os = "macos")'.dependencies]
+system-configuration = { version = "0.6.1", optional = true }
+
 [features]
 default = []
 
@@ -65,6 +68,7 @@ full = [
 client = ["hyper/client", "dep:tracing", "dep:futures-channel", "dep:tower-service"]
 client-legacy = ["client", "dep:socket2", "tokio/sync", "dep:libc"]
 client-proxy = ["client", "dep:base64", "dep:ipnet", "dep:percent-encoding"]
+client-proxy-system = ["dep:system-configuration"]
 
 server = ["hyper/server"]
 server-auto = ["server", "http1", "http2"]

src/client/proxy/matcher.rs

@@ -96,6 +96,20 @@ impl Matcher {
         Builder::from_env().build()
     }
 
+    /// Create a matcher from the environment or system.
+    ///
+    /// This checks the same environment variables as `from_env()`, and if not
+    /// set, checks the system configuration for values for the OS.
+    ///
+    /// This constructor is always available, but if the `client-proxy-system`
+    /// feature is enabled, it will check more configuration. Use this
+    /// constructor if you want to allow users to optionally enable more, or
+    /// use `from_env` if you do not want the values to change based on an
+    /// enabled feature.
+    pub fn from_system() -> Self {
+        Builder::from_system().build()
+    }
+
     /// Start a builder to configure a matcher.
     pub fn builder() -> Builder {
         Builder::default()
@@ -221,6 +235,16 @@ impl Builder {
         }
     }
 
+    fn from_system() -> Self {
+        #[allow(unused_mut)]
+        let mut builder = Self::from_env();
+
+        #[cfg(all(feature = "client-proxy-system", target_os = "macos"))]
+        mac::with_system(&mut builder);
+
+        builder
+    }
+
     /// Set the target proxy for all destinations.
     pub fn all<S>(mut self, val: S) -> Self
     where
@@ -531,6 +555,89 @@ mod builder {
     }
 }
 
+#[cfg(feature = "client-proxy-system")]
+#[cfg(target_os = "macos")]
+mod mac {
+    use system_configuration::core_foundation::base::{CFType, TCFType, TCFTypeRef};
+    use system_configuration::core_foundation::dictionary::CFDictionary;
+    use system_configuration::core_foundation::number::CFNumber;
+    use system_configuration::core_foundation::string::{CFString, CFStringRef};
+    use system_configuration::dynamic_store::SCDynamicStoreBuilder;
+    use system_configuration::sys::schema_definitions::{
+        kSCPropNetProxiesHTTPEnable, kSCPropNetProxiesHTTPPort, kSCPropNetProxiesHTTPProxy,
+        kSCPropNetProxiesHTTPSEnable, kSCPropNetProxiesHTTPSPort, kSCPropNetProxiesHTTPSProxy,
+    };
+
+    pub(super) fn with_system(builder: &mut super::Builder) {
+        let store = SCDynamicStoreBuilder::new("").build();
+
+        let proxies_map = if let Some(proxies_map) = store.get_proxies() {
+            proxies_map
+        } else {
+            return;
+        };
+
+        if builder.http.is_empty() {
+            let http_proxy_config = parse_setting_from_dynamic_store(
+                &proxies_map,
+                unsafe { kSCPropNetProxiesHTTPEnable },
+                unsafe { kSCPropNetProxiesHTTPProxy },
+                unsafe { kSCPropNetProxiesHTTPPort },
+            );
+            if let Some(http) = http_proxy_config {
+                builder.http = http;
+            }
+        }
+
+        if builder.https.is_empty() {
+            let https_proxy_config = parse_setting_from_dynamic_store(
+                &proxies_map,
+                unsafe { kSCPropNetProxiesHTTPSEnable },
+                unsafe { kSCPropNetProxiesHTTPSProxy },
+                unsafe { kSCPropNetProxiesHTTPSPort },
+            );
+
+            if let Some(https) = https_proxy_config {
+                builder.https = https;
+            }
+        }
+    }
+
+    fn parse_setting_from_dynamic_store(
+        proxies_map: &CFDictionary<CFString, CFType>,
+        enabled_key: CFStringRef,
+        host_key: CFStringRef,
+        port_key: CFStringRef,
+    ) -> Option<String> {
+        let proxy_enabled = proxies_map
+            .find(enabled_key)
+            .and_then(|flag| flag.downcast::<CFNumber>())
+            .and_then(|flag| flag.to_i32())
+            .unwrap_or(0)
+            == 1;
+
+        if proxy_enabled {
+            let proxy_host = proxies_map
+                .find(host_key)
+                .and_then(|host| host.downcast::<CFString>())
+                .map(|host| host.to_string());
+            let proxy_port = proxies_map
+                .find(port_key)
+                .and_then(|port| port.downcast::<CFNumber>())
+                .and_then(|port| port.to_i32());
+
+            return match (proxy_host, proxy_port) {
+                (Some(proxy_host), Some(proxy_port)) => Some(format!("{proxy_host}:{proxy_port}")),
+                (Some(proxy_host), None) => Some(proxy_host),
+                (None, Some(_)) => None,
+                (None, None) => None,
+            };
+        }
+
+        None
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;