fix(update): allow GitHub release asset redirects

Co-authored-by: Codex <noreply@openai.com>

backend/crates/gateway-host/src/system_update/mod.rs

@@ -39,6 +39,8 @@ use self::state::{
 };
 use self::swap::{replace_release_files, rollback_release};
 
+pub use self::release::validate_download_url;
+
 const APP_BINARY_NAME: &str = "codex-proxy-rs";
 const DEFAULT_WEB_DIST_DIR: &str = "/app/web/dist";
 const DEFAULT_GITHUB_API_BASE: &str = "https://api.github.com/repos";

backend/crates/gateway-host/src/system_update/release.rs

@@ -177,7 +177,8 @@ pub(crate) fn select_archive<'a>(
         })
 }
 
-pub(crate) fn validate_download_url(raw: &str, api_base: &str) -> Result<(), OperationError> {
+/// 校验 GitHub Release 资产 URL 及其重定向目标是否位于受信任边界内。
+pub fn validate_download_url(raw: &str, api_base: &str) -> Result<(), OperationError> {
     let url = reqwest::Url::parse(raw)
         .map_err(|error| invalid(format!("invalid download URL: {error}")))?;
     if local_download_allowed(&url, api_base) {
@@ -294,6 +295,7 @@ fn github_download_host_allowed(host: &str) -> bool {
         || host.ends_with(".github.com")
         || host == "objects.githubusercontent.com"
         || host.ends_with(".objects.githubusercontent.com")
+        || host == "release-assets.githubusercontent.com"
 }
 
 fn local_download_allowed(url: &reqwest::Url, api_base: &str) -> bool {

backend/crates/gateway-host/tests/system_update/mod.rs

@@ -10,7 +10,9 @@ use gateway_admin::model::system::{
 };
 use gateway_admin::ports::system::{SystemOperationErrorKind, SystemOperations};
 use gateway_core::engine::CancellationToken;
-use gateway_host::system_update::{ProcessSystemOperations, SystemUpdateConfig};
+use gateway_host::system_update::{
+    ProcessSystemOperations, SystemUpdateConfig, validate_download_url,
+};
 use sha2::{Digest as _, Sha256};
 use tar::{Builder, EntryType, Header};
 use wiremock::matchers::{method, path};
@@ -280,6 +282,17 @@ async fn update_should_reject_release_archive_from_untrusted_host() {
     );
 }
 
+#[test]
+fn update_should_trust_github_release_asset_redirect_host() {
+    assert!(
+        validate_download_url(
+            "https://release-assets.githubusercontent.com/github-production-release-asset/archive",
+            "https://api.github.com/repos",
+        )
+        .is_ok()
+    );
+}
+
 #[tokio::test]
 async fn update_should_reject_release_archive_with_unsafe_path() {
     let server = MockServer::start().await;