fix(github_copilot): disable shared device login on the proxy

litellm/llms/github_copilot/authenticator.py

@@ -1,6 +1,8 @@
 import json
 import os
+import threading
 import time
+from collections.abc import Callable
 from datetime import datetime
 from typing import Any, Final
 
@@ -25,6 +27,16 @@
 DEFAULT_GITHUB_DEVICE_CODE_URL: Final = "https://github.com/login/device/code"
 DEFAULT_GITHUB_ACCESS_TOKEN_URL: Final = "https://github.com/login/oauth/access_token"
 DEFAULT_GITHUB_API_KEY_URL: Final = "https://api.github.com/copilot_internal/v2/token"
+_SHARED_LOGIN_ALLOWED: Final = threading.Event()
+_SHARED_LOGIN_ALLOWED.set()
+_SHARED_LOGIN_DISABLED_MESSAGE: Final = (
+    "GitHub Copilot shared device login is disabled on the LiteLLM proxy. Create an LLM credential with Auth Type "
+    "'Per-user GitHub OAuth' and reference it from the deployment with litellm_credential_name"
+)
+
+
+def disable_github_copilot_shared_login() -> None:
+    _SHARED_LOGIN_ALLOWED.clear()
 
 
 @with_config(ConfigDict(extra="allow", strict=True))
@@ -62,8 +74,9 @@ def github_api_headers(
 
 
 class Authenticator:
-    def __init__(self) -> None:
+    def __init__(self, shared_login_allowed: Callable[[], bool] = _SHARED_LOGIN_ALLOWED.is_set) -> None:
         """Initialize the GitHub Copilot authenticator with configurable token paths."""
+        self._shared_login_allowed = shared_login_allowed
         # Token storage paths
         self.token_dir = os.getenv(
             "GITHUB_COPILOT_TOKEN_DIR",
@@ -74,7 +87,15 @@ def __init__(self) -> None:
             os.getenv("GITHUB_COPILOT_ACCESS_TOKEN_FILE", "access-token"),
         )
         self.api_key_file = os.path.join(self.token_dir, os.getenv("GITHUB_COPILOT_API_KEY_FILE", "api-key.json"))
-        self._ensure_token_dir()
+        if self._shared_login_allowed():
+            self._ensure_token_dir()
+
+    def _raise_if_shared_login_disabled(self) -> None:
+        if not self.is_shared_login_allowed():
+            raise GetAPIKeyError(message=_SHARED_LOGIN_DISABLED_MESSAGE, status_code=401)
+
+    def is_shared_login_allowed(self) -> bool:
+        return self._shared_login_allowed()
 
     def get_access_token(self) -> str:
         """
@@ -86,6 +107,7 @@ def get_access_token(self) -> str:
         Raises:
             GetAccessTokenError: If unable to obtain an access token after retries.
         """
+        self._raise_if_shared_login_disabled()
         try:
             with open(self.access_token_file, "r") as f:
                 access_token = f.read().strip()
@@ -100,8 +122,7 @@ def get_access_token(self) -> str:
                     "GitHub Copilot device-code login needs a human and cannot run inside a running event loop "
                     "or a worker thread (for example the LiteLLM proxy). Log in once outside the proxy with "
                     '`python -c "from litellm.llms.github_copilot.authenticator import Authenticator; '
-                    'Authenticator().get_access_token()"` and mount the resulting access-token file into '
-                    "the proxy, or set GITHUB_COPILOT_TOKEN_DIR to a directory that already holds it."
+                    'Authenticator().get_access_token()"`.'
                 ),
                 status_code=401,
             )
@@ -135,6 +156,7 @@ def get_api_key(self) -> str:
         Raises:
             GetAPIKeyError: If unable to obtain an API key.
         """
+        self._raise_if_shared_login_disabled()
         try:
             with open(self.api_key_file, "r") as f:
                 api_key_info = json.load(f)
@@ -184,6 +206,8 @@ def get_api_base(self) -> str | None:
         Returns:
             Optional[str]: The GitHub Copilot API endpoint, or None if not found.
         """
+        if not self._shared_login_allowed():
+            return None
         try:
             with open(self.api_key_file, "r") as f:
                 api_key_info: Final = json.load(f)

litellm/llms/github_copilot/chat/transformation.py

@@ -50,6 +50,8 @@ def _get_openai_compatible_provider_info(
         custom_llm_provider: str,
     ) -> tuple[str | None, str | None, str]:
         dynamic_api_base: Final = self.api_base_without_login(api_base)
+        if not self.authenticator.is_shared_login_allowed():
+            return dynamic_api_base, api_key, custom_llm_provider
         try:
             dynamic_api_key: Final = self.authenticator.get_api_key()
         except GetAPIKeyError as e:
@@ -95,13 +97,17 @@ def _transform_messages(
 
         return transformed_messages
 
-    def _copilot_headers(self, session_token: str | None) -> Mapping[str, str]:
+    def _copilot_headers(self, session_token: str | None, model: str) -> Mapping[str, str]:
         if session_token is not None:
             return get_copilot_default_headers(session_token)
         try:
             return get_copilot_default_headers(self.authenticator.get_api_key())
-        except GetAPIKeyError:
-            return {}
+        except GetAPIKeyError as exc:
+            raise AuthenticationError(
+                model=model,
+                llm_provider="github_copilot",
+                message=str(exc),
+            )
 
     def validate_environment(
         self,
@@ -121,7 +127,7 @@ def validate_environment(
             cast("dict[str, object]", litellm_params)  # cast-ok: litellm_params arrives as an untyped request dict
         )
         session_token: Final = user_session.token if user_session is not None else None
-        validated_headers: Final = {**self._copilot_headers(session_token), **parent_headers}
+        validated_headers: Final = {**self._copilot_headers(session_token, model), **parent_headers}
         if session_token is not None:
             # the caller's stored session token wins unconditionally, even over a
             # caller-supplied api_key or the parent's placeholder Authorization

litellm/main.py

@@ -69,7 +69,7 @@
     NADIR_DEFAULT_API_BASE,
     OPENAI_AUDIO_TRANSCRIPTION_PROVIDERS,
 )
-from litellm.exceptions import LiteLLMUnknownProvider
+from litellm.exceptions import AuthenticationError, LiteLLMUnknownProvider
 from litellm.integrations.custom_logger import CustomLogger
 from litellm.litellm_core_utils.asyncify import asyncify, run_async_function
 from litellm.litellm_core_utils.audio_utils.utils import (
@@ -2602,6 +2602,23 @@ def _complete_hosted_vllm(ctx: CompletionDispatchContext) -> _CompletionDispatch
     return response
 
 
+def _get_github_copilot_shared_api_key(
+    get_api_key: Callable[[], str],
+    model: str,
+    custom_llm_provider: str,
+) -> str:
+    from litellm.llms.github_copilot.common_utils import GetAPIKeyError
+
+    try:
+        return get_api_key()
+    except GetAPIKeyError as exc:
+        raise AuthenticationError(
+            model=model,
+            llm_provider=custom_llm_provider,
+            message=str(exc),
+        )
+
+
 def _complete_custom_openai(
     ctx: CompletionDispatchContext,
 ) -> _CompletionDispatchResult:
@@ -2654,18 +2671,22 @@ def _complete_custom_openai(
     # Add GitHub Copilot headers (same as /responses endpoint does)
     if custom_llm_provider == "github_copilot":
         from litellm.llms.github_copilot.authenticator import Authenticator
-        from litellm.llms.github_copilot.common_utils import (
-            get_copilot_default_headers,
-            pin_session_authorization,
-        )
+        from litellm.llms.github_copilot.common_utils import get_copilot_default_headers, pin_session_authorization
         from litellm.llms.github_copilot.per_user_auth import (
             require_github_copilot_user_session,
         )
 
         user_session: Final = require_github_copilot_user_session(litellm_params)
-        copilot_headers: Final = get_copilot_default_headers(
-            user_session.token if user_session is not None else Authenticator().get_api_key()
+        copilot_token: Final = (
+            user_session.token
+            if user_session is not None
+            else _get_github_copilot_shared_api_key(
+                get_api_key=Authenticator().get_api_key,
+                model=model,
+                custom_llm_provider=custom_llm_provider,
+            )
         )
+        copilot_headers: Final = get_copilot_default_headers(copilot_token)
         if extra_headers:
             copilot_headers.update(
                 cast("dict[str, str]", extra_headers)  # cast-ok: extra_headers is a str-valued request dict

litellm/proxy/proxy_server.py

@@ -1337,6 +1337,9 @@ async def proxy_startup_event(app: FastAPI) -> AsyncGenerator[ProxyLifespanState
         shared_aiohttp_session
     import json
 
+    from litellm.llms.github_copilot.authenticator import disable_github_copilot_shared_login
+
+    disable_github_copilot_shared_login()
     init_verbose_loggers()
 
     prometheus_multiproc_dir: Final = os.environ.get("PROMETHEUS_MULTIPROC_DIR")

tests/unit/llms/github_copilot/embedding/test_github_copilot_embedding_transformation.py

@@ -6,6 +6,7 @@
 
 
 from litellm.exceptions import AuthenticationError
+from litellm.llms.github_copilot.authenticator import Authenticator
 from litellm.llms.github_copilot.embedding.transformation import (
     GithubCopilotEmbeddingConfig,
 )
@@ -264,8 +265,7 @@ def test_validate_environment_uses_per_user_session_and_skips_authenticator():
     from litellm.llms.github_copilot.per_user_auth import GithubCopilotUserSession
 
     config = GithubCopilotEmbeddingConfig()
-    config.authenticator = MagicMock()
-    config.authenticator.get_api_key.side_effect = AssertionError("shared authenticator must not run")
+    config.authenticator = Authenticator(shared_login_allowed=lambda: False)
 
     session = GithubCopilotUserSession(token="user-copilot-token", api_base="https://api.githubcopilot.com")
     headers = config.validate_environment(
@@ -276,7 +276,23 @@ def test_validate_environment_uses_per_user_session_and_skips_authenticator():
         litellm_params={"github_copilot_user_session": session},
     )
     assert headers["Authorization"] == "Bearer user-copilot-token"
-    config.authenticator.get_api_key.assert_not_called()
+
+
+def test_shared_authentication_error_is_raised_when_login_is_disabled():
+    config = GithubCopilotEmbeddingConfig()
+    config.authenticator = Authenticator(shared_login_allowed=lambda: False)
+
+    with pytest.raises(AuthenticationError) as exc_info:
+        config.validate_environment(
+            headers={},
+            model="github_copilot/text-embedding-3-small",
+            messages=[],
+            optional_params={},
+            litellm_params={},
+        )
+
+    assert "GitHub Copilot shared device login is disabled on the LiteLLM proxy" in str(exc_info.value)
+    assert exc_info.value.status_code == 401
 
 
 def test_per_user_session_token_wins_over_caller_authorization():

tests/unit/llms/github_copilot/messages/test_github_copilot_messages_transformation.py

@@ -5,6 +5,7 @@
 
 
 from litellm.exceptions import AuthenticationError
+from litellm.llms.github_copilot.authenticator import Authenticator
 from litellm.llms.github_copilot.common_utils import GetAPIKeyError
 from litellm.llms.github_copilot.messages.transformation import (
     GithubCopilotAnthropicMessagesConfig,
@@ -329,9 +330,7 @@ def test_validate_environment_uses_per_user_session_and_skips_authenticator():
     from litellm.llms.github_copilot.per_user_auth import GithubCopilotUserSession
 
     config = GithubCopilotAnthropicMessagesConfig()
-    config.authenticator = MagicMock()
-    config.authenticator.get_api_key.side_effect = AssertionError("shared authenticator must not run")
-    config.authenticator.get_api_base.side_effect = AssertionError("shared authenticator must not run")
+    config.authenticator = Authenticator(shared_login_allowed=lambda: False)
 
     session = GithubCopilotUserSession(token="user-copilot-token", api_base="https://tenant.githubcopilot.com/")
     headers, api_base = config.validate_anthropic_messages_environment(
@@ -343,7 +342,23 @@ def test_validate_environment_uses_per_user_session_and_skips_authenticator():
     )
     assert headers["Authorization"] == "Bearer user-copilot-token"
     assert api_base == "https://tenant.githubcopilot.com"
-    config.authenticator.get_api_key.assert_not_called()
+
+
+def test_shared_authentication_error_is_raised_when_login_is_disabled():
+    config = GithubCopilotAnthropicMessagesConfig()
+    config.authenticator = Authenticator(shared_login_allowed=lambda: False)
+
+    with pytest.raises(AuthenticationError) as exc_info:
+        config.validate_anthropic_messages_environment(
+            headers={},
+            model="github_copilot/claude-sonnet-5.5",
+            messages=[],
+            optional_params={},
+            litellm_params={},
+        )
+
+    assert "GitHub Copilot shared device login is disabled on the LiteLLM proxy" in str(exc_info.value)
+    assert exc_info.value.status_code == 401
 
 
 def test_per_user_session_token_wins_over_caller_authorization():

tests/unit/llms/github_copilot/responses/test_github_copilot_responses_transformation.py

@@ -12,6 +12,8 @@
 import httpx
 import pytest
 import litellm
+from litellm.exceptions import AuthenticationError
+from litellm.llms.github_copilot.authenticator import Authenticator
 from litellm.litellm_core_utils.get_model_cost_map import get_model_cost_map
 from litellm.types.utils import LlmProviders
 from litellm.utils import ProviderConfigManager
@@ -759,8 +761,7 @@ def test_validate_environment_uses_per_user_session_and_skips_authenticator():
     from litellm.llms.github_copilot.per_user_auth import GithubCopilotUserSession
 
     config = GithubCopilotResponsesAPIConfig()
-    config.authenticator = MagicMock()
-    config.authenticator.get_api_key.side_effect = AssertionError("shared authenticator must not run")
+    config.authenticator = Authenticator(shared_login_allowed=lambda: False)
 
     session = GithubCopilotUserSession(token="user-copilot-token", api_base="https://api.githubcopilot.com")
     headers = config.validate_environment(
@@ -769,7 +770,21 @@ def test_validate_environment_uses_per_user_session_and_skips_authenticator():
         litellm_params={"github_copilot_user_session": session},
     )
     assert headers["Authorization"] == "Bearer user-copilot-token"
-    config.authenticator.get_api_key.assert_not_called()
+
+
+def test_shared_authentication_error_is_raised_when_login_is_disabled():
+    config = GithubCopilotResponsesAPIConfig()
+    config.authenticator = Authenticator(shared_login_allowed=lambda: False)
+
+    with pytest.raises(AuthenticationError) as exc_info:
+        config.validate_environment(
+            headers={},
+            model="github_copilot/gpt-5.4",
+            litellm_params={},
+        )
+
+    assert "GitHub Copilot shared device login is disabled on the LiteLLM proxy" in str(exc_info.value)
+    assert exc_info.value.status_code == 401
 
 
 def test_per_user_session_token_wins_over_caller_authorization():