fix: redact a data field in Action secret responses; test: secret echo suite

src/aegis_gitea_mcp/gitea/executor.py

@@ -14,7 +14,8 @@ Security properties (all covered by tests):
   OAuth client secret, ``extra_secrets`` and secret values submitted in a
   request body are replaced with ``[REDACTED]`` in every result, always;
 * secret-bearing response fields (:data:`~.encoding.SENSITIVE_RESPONSE_KEYS`, for example a
-  webhook's stored ``authorization_header``) are redacted by key name in every result except
+  webhook's stored ``authorization_header``, and ``data`` on Action secret operations) are
+  redacted by key name in every result except
   those of :data:`CREDENTIAL_ISSUING_OPERATIONS`, whatever ``SECRET_DETECTION_MODE`` says;
 * secret-pattern masking/blocking follows ``SECRET_DETECTION_MODE``, except for
   :data:`CREDENTIAL_ISSUING_OPERATIONS` whose purpose is to return a freshly
@@ -26,6 +27,7 @@ Security properties (all covered by tests):
 from __future__ import annotations
 
 import base64
+import itertools
 import json
 from collections.abc import Iterable, Mapping
 from dataclasses import dataclass, field
@@ -171,6 +173,8 @@ class _Call:
     sudo: str | None = None
     paginated: bool = False
     credential_issuing: bool = False
+    #: Action secret operations: a ``data`` field in the response is a secret value.
+    action_secret: bool = False
     header_data: str | None = None
     call_secrets: tuple[str, ...] = ()
 
@@ -183,6 +187,13 @@ class _Call:
         return next((value for key, value in self.query if key == name), None)
 
 
+def _is_action_secret_path(segments: list[str]) -> bool:
+    """True for ``.../actions/secrets[/...]`` raw paths (an Action secrets endpoint)."""
+    return any(
+        first == "actions" and second == "secrets" for first, second in itertools.pairwise(segments)
+    )
+
+
 def _classify(media_type: str) -> str:
     """Return ``json``, ``text`` or ``binary`` for a response media type."""
     if not media_type or media_type == "application/json" or media_type.endswith("+json"):
@@ -358,6 +369,7 @@ class GiteaExecutor:
             sudo=sudo,
             paginated=operation.paginated,
             credential_issuing=credential_issuing,
+            action_secret="Secret" in operation.operation_id,
             header_data=HEADER_DATA_OPERATIONS.get(operation.operation_id),
             call_secrets=tuple(
                 sensitive_body_values(submitted, secret_data="Secret" in operation.operation_id)
@@ -415,6 +427,7 @@ class GiteaExecutor:
             call.body = RequestBody(json=body, has_json=True)
         segments = call.display_path.split("/")
         call.call_secrets = tuple(sensitive_body_values(body, secret_data="secrets" in segments))
+        call.action_secret = _is_action_secret_path(segments)
         call.paginated = any(key in {"page", "limit"} for key, _ in call.query)
         return await self._send(call, identity)
 
@@ -624,8 +637,15 @@ class GiteaExecutor:
         payload = redact_exact(payload, secrets)
         if not exempt and "data" in payload:
             # Stored secrets (webhook authorization headers, ...) by field name: pattern
-            # masking cannot recognise them and SECRET_DETECTION_MODE may be off.
+            # masking cannot recognise them and SECRET_DETECTION_MODE may be off. Gitea
-            payload = {**payload, "data": redact_fields(payload["data"], SENSITIVE_RESPONSE_KEYS)}
+            # never returns an Action secret's value; should a response carry a ``data``
+            # field on a secret operation, it is the value and is redacted too.
+            keys = (
+                SENSITIVE_RESPONSE_KEYS | {"data"}
+                if call.action_secret
+                else SENSITIVE_RESPONSE_KEYS
+            )
+            payload = {**payload, "data": redact_fields(payload["data"], keys)}
         mode = self._settings.secret_detection_mode
         if mode != "off" and not exempt:
             if mode == "block":

tests/security/test_secret_echo.py

@@ -143,3 +143,268 @@ async def test_credential_issuing_operations_still_return_their_credential(
     assert minted in text
     # ... but the audit file never contains it.
     assert minted not in json.dumps(audit_entries())
+
+
+# Action secrets: names and metadata only, never values
+
+VALUE = "Sup3r-Secret-Action-Value!"
+SHORT_VALUE = "pw"
+
+
+def listing_with_values() -> list[dict[str, Any]]:
+    """What Gitea sends (names and creation times), plus a hostile ``data`` field."""
+    return [
+        {"name": "DEPLOY_KEY", "created": "2026-01-01T00:00:00Z", "data": VALUE},
+        {"name": "NPM_TOKEN", "created": "2026-01-02T00:00:00Z", "description": "ci"},
+    ]
+
+
+SECRET_LISTINGS = [
+    ("gitea_actions_repo_list_secrets", {"owner": "o", "repo": "r"}, "/repos/o/r/actions/secrets"),
+    ("gitea_actions_org_list_secrets", {"org": "acme"}, "/orgs/acme/actions/secrets"),
+    (
+        "gitea_api_request",
+        {"method": "GET", "path": "/repos/o/r/actions/secrets"},
+        "/repos/o/r/actions/secrets",
+    ),
+    (
+        "gitea_api_request",
+        {"method": "GET", "path": "/user/actions/secrets"},
+        "/user/actions/secrets",
+    ),
+]
+
+
+@pytest.mark.parametrize("mode", MODES)
+@pytest.mark.parametrize(("tool", "arguments", "path"), SECRET_LISTINGS)
+async def test_listing_secrets_returns_names_and_metadata_never_values(
+    httpx_mock: HTTPXMock, mode: str, tool: str, arguments: dict[str, Any], path: str
+) -> None:
+    mock_user(httpx_mock)
+    httpx_mock.add_response(url=f"{API}{path}", json=listing_with_values())
+    async with connected(server_settings(secret_detection_mode=mode)) as client:
+        text, structured = await call(client, tool, arguments)
+
+    assert VALUE not in text and VALUE not in json.dumps(structured)
+    names = [item["name"] for item in structured["data"]]
+    assert names == ["DEPLOY_KEY", "NPM_TOKEN"]
+    assert structured["data"][0]["created"] == "2026-01-01T00:00:00Z"
+    assert structured["data"][1]["description"] == "ci"
+
+
+async def test_a_secret_path_in_a_repository_is_not_mistaken_for_action_secrets(
+    httpx_mock: HTTPXMock,
+) -> None:
+    mock_user(httpx_mock)
+    httpx_mock.add_response(
+        url=f"{API}/repos/o/r/contents/secrets", json=[{"name": "a", "data": "kept"}]
+    )
+    async with connected() as client:
+        _, structured = await call(
+            client, "gitea_api_request", {"method": "GET", "path": "/repos/o/r/contents/secrets"}
+        )
+
+    assert structured["data"][0]["data"] == "kept"
+
+
+SECRET_WRITES = [
+    (
+        "gitea_actions_update_repo_secret",
+        {"owner": "o", "repo": "r", "secretname": "DEPLOY_KEY"},
+        "/repos/o/r/actions/secrets/DEPLOY_KEY",
+    ),
+    (
+        "gitea_actions_update_org_secret",
+        {"org": "acme", "secretname": "DEPLOY_KEY"},
+        "/orgs/acme/actions/secrets/DEPLOY_KEY",
+    ),
+    (
+        "gitea_actions_update_user_secret",
+        {"secretname": "DEPLOY_KEY"},
+        "/user/actions/secrets/DEPLOY_KEY",
+    ),
+]
+
+
+@pytest.mark.parametrize("mode", MODES)
+@pytest.mark.parametrize("value", [VALUE, SHORT_VALUE])
+@pytest.mark.parametrize(("tool", "arguments", "path"), SECRET_WRITES)
+async def test_updating_a_secret_never_echoes_the_submitted_value(
+    httpx_mock: HTTPXMock,
+    caplog: pytest.LogCaptureFixture,
+    mode: str,
+    value: str,
+    tool: str,
+    arguments: dict[str, Any],
+    path: str,
+) -> None:
+    caplog.set_level("DEBUG")
+    mock_user(httpx_mock)
+    # Success echoing the value, then a validation error repeating it (as Gitea 422s do).
+    httpx_mock.add_response(
+        method="PUT",
+        url=f"{API}{path}",
+        status_code=201,
+        json={"echo": value, "name": "DEPLOY_KEY"},
+    )
+    httpx_mock.add_response(
+        method="PUT",
+        url=f"{API}{path}",
+        status_code=422,
+        json={"message": f"invalid secret data: {value}", "errors": [f"data {value} too long"]},
+    )
+    async with connected(server_settings(secret_detection_mode=mode)) as client:
+        ok = await call(client, tool, {**arguments, "body": {"data": value}})
+        failed = await call(client, tool, {**arguments, "body": {"data": value}})
+
+    for text, structured in (ok, failed):
+        assert value not in text
+        assert value not in json.dumps(structured)
+    assert "[REDACTED]" in ok[0] and "[REDACTED]" in failed[0]
+    assert value not in json.dumps(audit_entries()) and value not in caplog.text
+
+
+async def test_the_raw_tool_also_hides_a_submitted_secret_value(httpx_mock: HTTPXMock) -> None:
+    mock_user(httpx_mock)
+    httpx_mock.add_response(
+        method="PUT",
+        url=f"{API}/repos/o/r/actions/secrets/K",
+        status_code=422,
+        json={"message": f"bad {VALUE}"},
+    )
+    async with connected() as client:
+        text, _ = await call(
+            client,
+            "gitea_api_request",
+            {
+                "method": "PUT",
+                "path": "/repos/o/r/actions/secrets/K",
+                "body": {"data": VALUE},
+            },
+        )
+
+    assert VALUE not in text and "[REDACTED]" in text
+
+
+# Other submitted credential fields
+
+CREDENTIAL_BODIES = [
+    (
+        "gitea_admin_create_user",
+        {},
+        "POST",
+        "/admin/users",
+        {"username": "bob", "email": "bob@example.com", "password": "Pa55word-Of-Bob"},
+    ),
+    (
+        "gitea_hook_repo_create_hook",
+        {"owner": "o", "repo": "r"},
+        "POST",
+        "/repos/o/r/hooks",
+        {"type": "gitea", "authorization_header": "Bearer hook-target-token-123", "config": {}},
+    ),
+    (
+        "gitea_repo_migrate",
+        {},
+        "POST",
+        "/repos/migrate",
+        {
+            "clone_addr": "https://example.org/x.git",
+            "repo_name": "x",
+            "auth_token": "migration-source-token-123",
+            "auth_password": "migration-source-pass-123",
+            "aws_secret_access_key": "aws-secret-access-key-value-123",
+        },
+    ),
+    (
+        "gitea_api_request",
+        {},
+        "POST",
+        "/orgs/acme/hooks",
+        {"config": {"secret": "shared-hook-secret-123", "url": "https://x.example"}},
+    ),
+]
+
+
+def secret_values(body: Any) -> list[str]:
+    found: list[str] = []
+    if isinstance(body, dict):
+        for key, item in body.items():
+            if isinstance(item, str) and key in {
+                "password",
+                "authorization_header",
+                "auth_token",
+                "auth_password",
+                "aws_secret_access_key",
+                "secret",
+            }:
+                found.append(item)
+            else:
+                found.extend(secret_values(item))
+    return found
+
+
+@pytest.mark.parametrize("mode", MODES)
+@pytest.mark.parametrize(("tool", "arguments", "method", "path", "body"), CREDENTIAL_BODIES)
+async def test_submitted_credentials_are_redacted_from_results(
+    httpx_mock: HTTPXMock,
+    mode: str,
+    tool: str,
+    arguments: dict[str, Any],
+    method: str,
+    path: str,
+    body: dict[str, Any],
+) -> None:
+    mock_user(httpx_mock)
+    secrets = secret_values(body)
+    assert secrets
+    httpx_mock.add_response(
+        method=method,
+        url=f"{API}{path}",
+        status_code=422,
+        json={"message": "rejected: " + " ".join(secrets), "errors": secrets},
+    )
+    request = (
+        {"method": method, "path": path, "body": body}
+        if tool == "gitea_api_request"
+        else {**arguments, "body": body}
+    )
+    async with connected(server_settings(secret_detection_mode=mode)) as client:
+        text, structured = await call(client, tool, request)
+
+    for secret in secrets:
+        assert secret not in text and secret not in json.dumps(structured)
+        assert secret not in json.dumps(audit_entries())
+    assert "[REDACTED]" in text
+
+
+# Credential-issuing operations: the credential goes to the caller, nowhere else
+
+
+async def test_issued_credentials_reach_the_caller_but_not_the_audit_file_or_the_logs(
+    httpx_mock: HTTPXMock, caplog: pytest.LogCaptureFixture
+) -> None:
+    caplog.set_level("DEBUG")
+    mock_user(httpx_mock)
+    token = "9f8e7d6c5b4a39281706f5e4d3c2b1a099887766"
+    registration = "runner-registration-token-0123456789ABCDEF"
+    httpx_mock.add_response(
+        method="POST", url=f"{API}/users/alice/tokens", json={"id": 1, "name": "ci", "sha1": token}
+    )
+    httpx_mock.add_response(
+        method="POST",
+        url=f"{API}/admin/actions/runners/registration-token",
+        headers={"token": registration},
+        status_code=200,
+    )
+    async with connected(server_settings(secret_detection_mode="block")) as client:
+        created, _ = await call(
+            client, "gitea_user_create_token", {"username": "alice", "body": {"name": "ci"}}
+        )
+        runner, _ = await call(client, "gitea_admin_create_runner_registration_token", {})
+
+    assert token in created and registration in runner  # the documented exemption (W-07)
+    audit_text = json.dumps(audit_entries())
+    for secret in (token, registration):
+        assert secret not in audit_text
+        assert secret not in caplog.text