Broker credential aliases in child environments (#40484)

## What changed

- Discover supported credentials inherited from the parent even when their canonical provider variable is filtered from the child environment.
- Replace matching values and credentials embedded in longer child environment values with broker dummies, then restore only aliases that the broker virtualized.
- Preserve provider and host bindings when selecting credentials for outbound requests, including GitHub Enterprise and custom OpenAI hosts.
- Expose helpers for identifying provider and binding variables, plus an API for virtualizing credential-bearing text before it is persisted.

## Testing

- Extend credential broker tests for filtered parent variables, exact and embedded aliases, text virtualization, user overrides, and host-bound GitHub and OpenAI credentials.

GitOrigin-RevId: 55d673911900470aab4e206d0f4f5e62ed3611ae

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

@@ -51,10 +51,13 @@ fn virtualize_child_env_replaces_supported_credentials() {
     let broker = CredentialBroker::new(/*enabled*/ true);
     let github_token = "github_pat_11AA0bbCC_abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGH";
     let openai_api_key = "sk-proj-abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_";
+    let authorization = format!("Bearer {github_token}");
     let mut env = env_map([
         ("GH_TOKEN", github_token),
+        ("HOMEBREW_GITHUB_API_TOKEN", github_token),
+        ("AUTH_HEADER", authorization.as_str()),
         ("OPENAI_API_KEY", openai_api_key),
-        ("GH_ENTERPRISE_TOKEN", "ghp-enterprise-real"),
+        ("GH_ENTERPRISE_TOKEN", github_token),
     ]);
 
     broker.virtualize_child_env(&mut env);
@@ -63,12 +66,37 @@ fn virtualize_child_env_replaces_supported_credentials() {
     let openai_dummy = env.get("OPENAI_API_KEY").expect("dummy OpenAI API key");
     assert_credential_shape(github_token, github_dummy, "github_pat_");
     assert_credential_shape(openai_api_key, openai_dummy, "sk-proj-");
+    assert_eq!(env.get("HOMEBREW_GITHUB_API_TOKEN"), Some(github_dummy));
+    assert_eq!(env.get("GH_ENTERPRISE_TOKEN"), Some(github_dummy));
+    assert_eq!(
+        env.get("AUTH_HEADER"),
+        Some(&format!("Bearer {github_dummy}"))
+    );
+    let mut persisted_credentials = format!("{github_token}\n{openai_api_key}");
+    assert!(broker.virtualize_text(&mut persisted_credentials, &env));
+    assert_eq!(
+        persisted_credentials,
+        format!("{github_dummy}\n{openai_dummy}")
+    );
+    let mut filtered_env = env.clone();
+    filtered_env.remove("OPENAI_API_KEY");
+    let mut excluded_credentials = format!("{github_token}\n{openai_api_key}");
+    assert!(!broker.virtualize_text(&mut excluded_credentials, &filtered_env));
+    assert_eq!(excluded_credentials, format!("{github_dummy}\n"));
+    let mut excluded_dummies = format!("{github_dummy}\n{openai_dummy}");
+    assert!(!broker.virtualize_text(&mut excluded_dummies, &filtered_env));
+    assert_eq!(excluded_dummies, format!("{github_dummy}\n"));
     let mut command = vec![
         format!("Authorization: Bearer {github_dummy}"),
         format!("Authorization: Bearer {openai_dummy}"),
     ];
+    let github_dummy = github_dummy.clone();
     let openai_dummy = openai_dummy.clone();
     env.insert("OPENAI_API_KEY".to_string(), "sk-user-override".to_string());
+    env.insert(
+        "GIT_CONFIG_VALUE_0".to_string(),
+        format!("Authorization: Bearer {github_dummy}"),
+    );
     assert_eq!(
         brokered_credential_dummy_env_keys(&env),
         vec!["GH_TOKEN".to_string()]
@@ -76,17 +104,36 @@ fn virtualize_child_env_replaces_supported_credentials() {
 
     broker.restore_child_env(&mut env, &mut command);
     assert_eq!(env.get("GH_TOKEN").map(String::as_str), Some(github_token));
+    assert_eq!(
+        env.get("HOMEBREW_GITHUB_API_TOKEN").map(String::as_str),
+        Some(github_token)
+    );
+    assert_eq!(
+        env.get("GH_ENTERPRISE_TOKEN").map(String::as_str),
+        Some(github_token)
+    );
+    assert_eq!(env.get("AUTH_HEADER"), Some(&authorization));
     assert_eq!(
         env.get("OPENAI_API_KEY").map(String::as_str),
         Some("sk-user-override")
     );
+    assert_eq!(
+        env.get("GIT_CONFIG_VALUE_0"),
+        Some(&format!("Authorization: Bearer {github_dummy}"))
+    );
     assert_eq!(
         command,
         vec![
-            format!("Authorization: Bearer {github_token}"),
+            format!("Authorization: Bearer {github_dummy}"),
             format!("Authorization: Bearer {openai_dummy}"),
         ]
     );
+
+    env.insert("GH_TOKEN".to_string(), openai_dummy.clone());
+    env.insert("OPENAI_API_KEY".to_string(), github_dummy.clone());
+    broker.restore_child_env(&mut env, &mut []);
+    assert_eq!(env.get("GH_TOKEN"), Some(&openai_dummy));
+    assert_eq!(env.get("OPENAI_API_KEY"), Some(&github_dummy));
 }
 
 #[cfg(windows)]
@@ -130,6 +177,119 @@ fn virtualize_child_env_preserves_live_dummy_mappings() {
 
     assert_eq!(authorization(&first_headers), Some("Bearer ghp-real-one"));
     assert_eq!(authorization(&second_headers), Some("Bearer ghp-real-two"));
+
+    let mut alias_only = env_map([("HOMEBREW_GITHUB_API_TOKEN", "ghp-real-one")]);
+    broker.virtualize_child_env(&mut alias_only);
+    assert_eq!(
+        alias_only.get("HOMEBREW_GITHUB_API_TOKEN"),
+        Some(first_dummy)
+    );
+    broker.restore_child_env(&mut alias_only, &mut []);
+    assert_eq!(alias_only["HOMEBREW_GITHUB_API_TOKEN"], "ghp-real-one");
+
+    let mut overridden = env_map([
+        ("GH_TOKEN", "ghp-real-two"),
+        ("HOMEBREW_GITHUB_API_TOKEN", "ghp-real-one"),
+    ]);
+    broker.virtualize_child_env(&mut overridden);
+    assert_eq!(overridden.get("GH_TOKEN"), Some(second_dummy));
+    assert_eq!(
+        overridden.get("HOMEBREW_GITHUB_API_TOKEN"),
+        Some(first_dummy)
+    );
+
+    let mut cloud_alias = env_map([
+        ("GH_TOKEN", "ghp-real-one"),
+        ("GITHUB_TOKEN", "ghp-real-one"),
+    ]);
+    broker.virtualize_child_env(&mut cloud_alias);
+    cloud_alias.insert("GITHUB_TOKEN".to_string(), first_dummy.clone());
+    broker.restore_child_env(&mut cloud_alias, &mut []);
+    assert_eq!(cloud_alias["GITHUB_TOKEN"], "ghp-real-one");
+
+    let mut distinct_credentials = env_map([
+        ("GH_TOKEN", "ghp-primary-secret"),
+        ("GITHUB_TOKEN", "ghp-secondary-secret"),
+    ]);
+    broker.virtualize_child_env(&mut distinct_credentials);
+    let secondary_dummy = distinct_credentials["GITHUB_TOKEN"].clone();
+    distinct_credentials.remove("GITHUB_TOKEN");
+    distinct_credentials.insert("GH_TOKEN".to_string(), secondary_dummy.clone());
+    broker.virtualize_child_env(&mut distinct_credentials);
+    broker.restore_child_env(&mut distinct_credentials, &mut []);
+    assert_eq!(distinct_credentials["GH_TOKEN"], secondary_dummy);
+}
+
+#[test]
+fn virtualize_child_env_replaces_aliases_of_filtered_parent_credentials() {
+    let broker = CredentialBroker::new(/*enabled*/ true);
+    let github_token = "ghp_abcdefghijklmnopqrstuvwxyz1234567890";
+    let authorization_header = format!("Bearer {github_token}");
+    let parent_env = env_map([
+        ("GH_TOKEN", github_token),
+        ("HOMEBREW_GITHUB_API_TOKEN", github_token),
+    ]);
+    let mut child_env = env_map([
+        ("HOMEBREW_GITHUB_API_TOKEN", github_token),
+        ("AUTH_HEADER", authorization_header.as_str()),
+    ]);
+
+    broker.discover_parent_credentials(&parent_env, &child_env);
+    broker.virtualize_child_env(&mut child_env);
+
+    let dummy = child_env["HOMEBREW_GITHUB_API_TOKEN"].clone();
+    assert_ne!(dummy, github_token);
+    assert_eq!(child_env["AUTH_HEADER"], format!("Bearer {dummy}"));
+    assert!(!child_env.contains_key("GH_TOKEN"));
+
+    let mut headers = headers_with_bearer(&dummy);
+    broker.inject_request_headers("api.github.com", &mut headers);
+    assert_eq!(authorization(&headers), Some(authorization_header.as_str()));
+
+    broker.restore_child_env(&mut child_env, &mut []);
+    assert_eq!(child_env["HOMEBREW_GITHUB_API_TOKEN"], github_token);
+    assert_eq!(child_env["AUTH_HEADER"], authorization_header);
+    assert!(!child_env.contains_key("GH_TOKEN"));
+}
+
+#[test]
+fn virtualize_child_env_binds_filtered_enterprise_credentials_to_child_host() {
+    let github_token = "ghp_abcdefghijklmnopqrstuvwxyz1234567890";
+    let authorization_header = format!("Bearer {github_token}");
+
+    for (parent_host, include_cloud_token) in [
+        (None, false),
+        (Some("github.previous.example"), false),
+        (None, true),
+    ] {
+        let broker = CredentialBroker::new(/*enabled*/ true);
+        let mut parent_env = env_map([("GH_ENTERPRISE_TOKEN", github_token)]);
+        if let Some(parent_host) = parent_host {
+            parent_env.insert("GH_HOST".to_string(), parent_host.to_string());
+        }
+        if include_cloud_token {
+            parent_env.insert("GH_TOKEN".to_string(), github_token.to_string());
+        }
+        let mut child_env = env_map([
+            ("GH_HOST", "github.current.example"),
+            ("AUTH_HEADER", authorization_header.as_str()),
+        ]);
+
+        broker.discover_parent_credentials(&parent_env, &child_env);
+        broker.virtualize_child_env(&mut child_env);
+
+        assert_ne!(child_env["AUTH_HEADER"], authorization_header);
+        let mut headers = headers_with_authorization(&child_env["AUTH_HEADER"]);
+        broker.inject_request_headers("github.current.example", &mut headers);
+        assert_eq!(authorization(&headers), Some(authorization_header.as_str()));
+
+        let mut previous_headers = headers_with_authorization(&child_env["AUTH_HEADER"]);
+        broker.inject_request_headers("github.previous.example", &mut previous_headers);
+        assert_eq!(
+            authorization(&previous_headers),
+            Some(child_env["AUTH_HEADER"].as_str())
+        );
+    }
 }
 
 #[test]
@@ -192,6 +352,12 @@ fn virtualize_child_env_preserves_unbound_enterprise_token() {
     assert_eq!(env["GH_ENTERPRISE_TOKEN"], "ghp-enterprise-real");
     assert_eq!(headers, headers_with_bearer(inert_token));
     assert!(!broker.host_requires_mitm("attacker.example"));
+
+    env.insert("GH_HOST".to_string(), "github.example.com".to_string());
+    broker.virtualize_child_env(&mut env);
+    let mut headers = headers_with_bearer(&env["GH_ENTERPRISE_TOKEN"]);
+    broker.inject_request_headers("github.example.com", &mut headers);
+    assert_eq!(authorization(&headers), Some("Bearer ghp-enterprise-real"));
 }
 
 #[test]
@@ -294,6 +460,7 @@ fn openai_credentials_bind_only_to_default_and_configured_trusted_hosts() {
     ]);
     broker.virtualize_child_env(&mut env);
     assert!(brokered_credential_env_keys(&env).any(|key| key == "OPENAI_BASE_URL"));
+    assert!(brokered_credential_binding_env_keys(&env).any(|key| key == "OPENAI_BASE_URL"));
     let dummy = &env["OPENAI_API_KEY"];
 
     for (host, expected_credential) in [
@@ -330,6 +497,7 @@ fn github_cloud_credentials_match_ghe_com_host_hint() {
     let broker = CredentialBroker::new(/*enabled*/ true);
     let mut env = env_map([("GH_HOST", "astemu.ghe.com"), ("GH_TOKEN", "ghp-real")]);
     broker.virtualize_child_env(&mut env);
+    assert!(!brokered_credential_binding_env_keys(&env).any(|key| key == "GH_HOST"));
     let github_token = env.get("GH_TOKEN").expect("dummy GitHub token");
     let mut headers = headers_with_bearer(github_token);
 
@@ -362,18 +530,77 @@ fn github_enterprise_credentials_bind_to_gh_host() {
     let broker = CredentialBroker::new(/*enabled*/ true);
     let mut env = env_map([
         ("GH_HOST", "github.example.com"),
+        ("GH_TOKEN", "ghp-enterprise-real"),
         ("GH_ENTERPRISE_TOKEN", "ghp-enterprise-real"),
+        ("AUTH_HEADER", "Bearer ghp-enterprise-real"),
     ]);
     broker.virtualize_child_env(&mut env);
+    let github_dummy = env["GH_TOKEN"].clone();
     assert!(brokered_credential_env_keys(&env).any(|key| key == "GH_HOST"));
+    assert!(brokered_credential_binding_env_keys(&env).any(|key| key == "GH_HOST"));
     let github_token = env
         .get("GH_ENTERPRISE_TOKEN")
         .expect("dummy GitHub enterprise token");
+    assert_ne!(github_token, &github_dummy);
     let mut headers = headers_with_bearer(github_token);
 
     broker.inject_request_headers("github.example.com", &mut headers);
 
     assert_eq!(authorization(&headers), Some("Bearer ghp-enterprise-real"));
+    assert_eq!(env["AUTH_HEADER"], format!("Bearer {github_token}"));
+    let mut alias_headers = headers_with_authorization(&env["AUTH_HEADER"]);
+    broker.inject_request_headers("github.example.com", &mut alias_headers);
+    assert_eq!(
+        authorization(&alias_headers),
+        Some("Bearer ghp-enterprise-real")
+    );
+    let mut persisted_alias = "Bearer ghp-enterprise-real".to_string();
+    assert!(broker.virtualize_text(&mut persisted_alias, &env));
+    assert_eq!(persisted_alias, format!("Bearer {github_token}"));
+    assert_eq!(
+        brokered_credential_dummy_env_keys(&env).first(),
+        Some(&"GH_ENTERPRISE_TOKEN".to_string())
+    );
+    let mut cloud_headers = headers_with_bearer(&github_dummy);
+    broker.inject_request_headers("github.example.com", &mut cloud_headers);
+    assert_eq!(cloud_headers, headers_with_bearer(&github_dummy));
+    let mut enterprise_headers = headers_with_bearer(github_token);
+    broker.inject_request_headers("api.github.com", &mut enterprise_headers);
+    assert_eq!(enterprise_headers, headers_with_bearer(github_token));
+    let mut cloud_only = env_map([
+        ("GH_HOST", "github.example.com"),
+        ("GH_TOKEN", "ghp-enterprise-real"),
+        ("AUTH_HEADER", "Bearer ghp-enterprise-real"),
+    ]);
+    broker.virtualize_child_env(&mut cloud_only);
+    assert_eq!(cloud_only["AUTH_HEADER"], format!("Bearer {github_dummy}"));
     assert!(broker.host_requires_mitm("github.example.com"));
-    assert!(!broker.host_requires_mitm("api.github.com"));
+    assert!(broker.host_requires_mitm("api.github.com"));
+
+    env.insert("GH_HOST".to_string(), "attacker.example".to_string());
+    env.insert("GH_ENTERPRISE_TOKEN".to_string(), github_dummy.clone());
+    broker.virtualize_child_env(&mut env);
+    let mut attacker_headers = headers_with_bearer(&github_dummy);
+    broker.inject_request_headers("attacker.example", &mut attacker_headers);
+    assert_eq!(attacker_headers, headers_with_bearer(&github_dummy));
+    assert!(!broker.host_requires_mitm("attacker.example"));
+
+    let mut alternate_enterprise_key = env_map([
+        ("GH_HOST", "github.alternate.example"),
+        ("GH_TOKEN", "ghp-alternate-real"),
+        ("GITHUB_ENTERPRISE_TOKEN", "ghp-alternate-real"),
+        ("AUTH_HEADER", "Bearer ghp-alternate-real"),
+    ]);
+    broker.virtualize_child_env(&mut alternate_enterprise_key);
+    assert_eq!(
+        alternate_enterprise_key["AUTH_HEADER"],
+        format!(
+            "Bearer {}",
+            alternate_enterprise_key["GITHUB_ENTERPRISE_TOKEN"]
+        )
+    );
+    assert_eq!(
+        brokered_credential_dummy_env_keys(&alternate_enterprise_key).first(),
+        Some(&"GITHUB_ENTERPRISE_TOKEN".to_string())
+    );
 }