Harden managed proxy setup for sandboxed executions (#34641)

## What changed

- Make the generated Linux proxy socket directory readable inside restricted
  `bubblewrap` sandboxes so the proxy bridge can connect.
- Route `WS_PROXY` and `WSS_PROXY` through the Linux managed proxy bridge.
- Remove inherited proxy attribution tokens from unscoped executions while
  continuing to replace them with the current token for scoped executions.

## Testing

- Exercise `WSS_PROXY` routing with a minimal filesystem policy.
- Cover attribution-token removal and replacement during environment setup.

GitOrigin-RevId: 2f14ddb26baab0147a786bc354d93eb5aad059f3

codex-rs/exec-server/src/process_sandbox_tests.rs

@@ -5,6 +5,7 @@ use std::time::Duration;
 #[cfg(target_os = "macos")]
 use codex_network_proxy::ManagedNetworkSandboxContext;
 use codex_network_proxy::NetworkProxyConfig;
+use codex_network_proxy::PROXY_ATTRIBUTION_TOKEN_ENV_KEY;
 use codex_network_proxy::RemoteNetworkProxyConfig;
 use codex_network_proxy::RemoteNetworkProxyLaunchConfig;
 #[cfg(windows)]
@@ -264,6 +265,10 @@ async fn native_request_handles_remote_proxy_config_for_platform() {
     let env = HashMap::from([
         ("HTTP_PROXY".to_string(), stale_proxy.clone()),
         ("TEST_ENV".to_string(), "value".to_string()),
+        (
+            PROXY_ATTRIBUTION_TOKEN_ENV_KEY.to_string(),
+            "foreign-token".to_string(),
+        ),
     ]);
 
     let prepared = prepare_exec_request(&params, env, /*runtime_paths*/ None)
@@ -280,6 +285,7 @@ async fn native_request_handles_remote_proxy_config_for_platform() {
     let http_proxy = prepared.env.get("HTTP_PROXY").expect("HTTP proxy env");
     assert_ne!(http_proxy, &stale_proxy);
     assert!(http_proxy.starts_with("http://127.0.0.1:"));
+    assert!(!prepared.env.contains_key(PROXY_ATTRIBUTION_TOKEN_ENV_KEY));
     let proxy_addr: SocketAddr = http_proxy
         .strip_prefix("http://")
         .expect("HTTP proxy scheme")

codex-rs/linux-sandbox/src/linux_run_main.rs

@@ -167,7 +167,7 @@ pub fn run_main() -> ! {
     ensure_inner_stage_mode_is_valid(apply_seccomp_then_exec, use_legacy_landlock);
     let EffectivePermissions {
         permission_profile,
-        file_system_sandbox_policy,
+        mut file_system_sandbox_policy,
         network_sandbox_policy,
     } = resolve_permission_profile(permission_profile).unwrap_or_else(|err| panic!("{err}"));
     ensure_legacy_landlock_mode_supports_policy(
@@ -218,11 +218,14 @@ pub fn run_main() -> ! {
         // Outer stage: bubblewrap first, then re-enter this binary in the
         // sandboxed environment to apply seccomp. This path never falls back
         // to legacy Landlock on failure.
-        let proxy_route_spec =
+        let proxy_route_spec = if allow_network_for_proxy {
-            if allow_network_for_proxy {
+            let (proxy_route_spec, socket_dir) = prepare_host_proxy_route_spec()
-                Some(prepare_host_proxy_route_spec().unwrap_or_else(|err| {
+                .unwrap_or_else(|err| panic!("failed to prepare host proxy routing bridge: {err}"));
-                    panic!("failed to prepare host proxy routing bridge: {err}")
+            file_system_sandbox_policy = file_system_sandbox_policy.with_additional_readable_roots(
-                }))
+                &sandbox_policy_cwd,
+                std::slice::from_ref(&socket_dir),
+            );
+            Some(proxy_route_spec)
         } else {
             None
         };

codex-rs/linux-sandbox/src/proxy_routing.rs

@@ -1,5 +1,6 @@
 use codex_network_proxy::PROXY_ATTRIBUTION_TOKEN_ENV_KEY;
 use codex_network_proxy::write_attribution_frame;
+use codex_utils_absolute_path::AbsolutePathBuf;
 use serde::Deserialize;
 use serde::Serialize;
 use std::collections::BTreeMap;
@@ -29,6 +30,8 @@ use url::Url;
 const PROXY_ENV_KEYS: &[&str] = &[
     "HTTP_PROXY",
     "HTTPS_PROXY",
+    "WS_PROXY",
+    "WSS_PROXY",
     "ALL_PROXY",
     "FTP_PROXY",
     "YARN_HTTP_PROXY",
@@ -72,7 +75,7 @@ struct ProxyRoutePlan {
     has_proxy_config: bool,
 }
 
-pub(crate) fn prepare_host_proxy_route_spec() -> io::Result<String> {
+pub(crate) fn prepare_host_proxy_route_spec() -> io::Result<(String, AbsolutePathBuf)> {
     let (attribution_token, plan) = extract_attribution_token_and_plan(std::env::vars().collect());
     // SAFETY: the sandbox helper is single-threaded here, before it forks bridge workers or
     // executes the user command.
@@ -93,6 +96,7 @@ pub(crate) fn prepare_host_proxy_route_spec() -> io::Result<String> {
     let _ = cleanup_stale_proxy_socket_dirs_in(socket_parent_dir.as_path());
 
     let socket_dir = create_proxy_socket_dir()?;
+    let readable_socket_dir = AbsolutePathBuf::relative_to_current_dir(&socket_dir)?;
     let mut socket_by_endpoint: BTreeMap<SocketAddr, PathBuf> = BTreeMap::new();
     let mut next_index = 0usize;
     for route in &plan.routes {
@@ -128,7 +132,8 @@ pub(crate) fn prepare_host_proxy_route_spec() -> io::Result<String> {
         });
     }
 
-    serde_json::to_string(&ProxyRouteSpec { routes }).map_err(io::Error::other)
+    let spec = serde_json::to_string(&ProxyRouteSpec { routes }).map_err(io::Error::other)?;
+    Ok((spec, readable_socket_dir))
 }
 
 fn extract_attribution_token_and_plan(
@@ -732,6 +737,8 @@ mod tests {
     fn recognizes_proxy_env_keys_case_insensitively() {
         assert_eq!(is_proxy_env_key("HTTP_PROXY"), true);
         assert_eq!(is_proxy_env_key("http_proxy"), true);
+        assert_eq!(is_proxy_env_key("WS_PROXY"), true);
+        assert_eq!(is_proxy_env_key("wss_proxy"), true);
         assert_eq!(is_proxy_env_key("PATH"), false);
     }
 

codex-rs/linux-sandbox/tests/suite/managed_proxy.rs

@@ -4,6 +4,13 @@
 use codex_core::exec_env::create_env;
 use codex_protocol::config_types::ShellEnvironmentPolicy;
 use codex_protocol::models::PermissionProfile;
+use codex_protocol::permissions::FileSystemAccessMode;
+use codex_protocol::permissions::FileSystemPath;
+use codex_protocol::permissions::FileSystemSandboxEntry;
+use codex_protocol::permissions::FileSystemSandboxPolicy;
+use codex_protocol::permissions::FileSystemSpecialPath;
+use codex_protocol::permissions::NetworkSandboxPolicy;
+use codex_utils_absolute_path::AbsolutePathBuf;
 use pretty_assertions::assert_eq;
 use std::collections::HashMap;
 use std::io::Read;
@@ -28,6 +35,8 @@ const MANAGED_PROXY_PERMISSION_ERR_SNIPPETS: &[&str] = &[
 const PROXY_ENV_KEYS: &[&str] = &[
     "HTTP_PROXY",
     "HTTPS_PROXY",
+    "WS_PROXY",
+    "WSS_PROXY",
     "ALL_PROXY",
     "FTP_PROXY",
     "YARN_HTTP_PROXY",
@@ -209,14 +218,40 @@ async fn managed_proxy_mode_routes_through_bridge_and_blocks_direct_egress() {
         "HTTP_PROXY".to_string(),
         format!("http://127.0.0.1:{proxy_port}"),
     );
+    env.insert(
+        "WSS_PROXY".to_string(),
+        format!("http://127.0.0.1:{proxy_port}"),
+    );
+
+    let sandbox_helper_dir = std::path::Path::new(env!("CARGO_BIN_EXE_codex-linux-sandbox"))
+        .parent()
+        .expect("sandbox helper should have a parent");
+    let file_system_sandbox_policy =
+        FileSystemSandboxPolicy::restricted(vec![FileSystemSandboxEntry {
+            path: FileSystemPath::Special {
+                value: FileSystemSpecialPath::Minimal,
+            },
+            access: FileSystemAccessMode::Read,
+            missing_path_behavior: None,
+        }])
+        .with_additional_readable_roots(
+            std::env::current_dir()
+                .expect("current directory should exist")
+                .as_path(),
+            &[AbsolutePathBuf::try_from(sandbox_helper_dir).expect("absolute helper dir")],
+        );
+    let permission_profile = PermissionProfile::from_runtime_permissions(
+        &file_system_sandbox_policy,
+        NetworkSandboxPolicy::Restricted,
+    );
 
     let routed_output = run_linux_sandbox_direct(
         &[
             "bash",
             "-c",
-            "proxy=\"${HTTP_PROXY#*://}\"; host=\"${proxy%%:*}\"; port=\"${proxy##*:}\"; exec 3<>/dev/tcp/${host}/${port}; printf 'GET http://example.com/ HTTP/1.1\\r\\nHost: example.com\\r\\n\\r\\n' >&3; IFS= read -r line <&3; printf '%s\\n' \"$line\"",
+            "proxy=\"${WSS_PROXY#*://}\"; host=\"${proxy%%:*}\"; port=\"${proxy##*:}\"; exec 3<>/dev/tcp/${host}/${port}; printf 'GET http://example.com/ HTTP/1.1\\r\\nHost: example.com\\r\\n\\r\\n' >&3; IFS= read -r line <&3; printf '%s\\n' \"$line\"",
         ],
-        &PermissionProfile::Disabled,
+        &permission_profile,
         /*allow_network_for_proxy*/ true,
         env.clone(),
         NETWORK_TIMEOUT_MS,

codex-rs/network-proxy/src/proxy.rs

@@ -902,6 +902,8 @@ impl NetworkProxy {
                 PROXY_ATTRIBUTION_TOKEN_ENV_KEY.to_string(),
                 execution_scope.attribution_token.clone(),
             );
+        } else {
+            env.remove(PROXY_ATTRIBUTION_TOKEN_ENV_KEY);
         }
         let expose_socks_port = self.socks_enabled;
         #[cfg(target_os = "windows")]
@@ -1712,9 +1714,23 @@ mod tests {
 
         let scoped = proxy.for_execution("remote-env", "execution-1", "token-1".to_string())?;
         let launch = scoped.remote_launch_config().await?;
+        let prepared = scoped.prepare_for_optional_environment(
+            HashMap::from([(
+                PROXY_ATTRIBUTION_TOKEN_ENV_KEY.to_string(),
+                "foreign-token".to_string(),
+            )]),
+            /*environment_id*/ None,
+        )?;
 
         assert_eq!(launch.environment_id.as_deref(), Some("remote-env"));
         assert_eq!(launch.execution_id.as_deref(), Some("execution-1"));
+        assert_eq!(
+            prepared
+                .env
+                .get(PROXY_ATTRIBUTION_TOKEN_ENV_KEY)
+                .map(String::as_str),
+            Some("token-1")
+        );
         Ok(())
     }