"""Network Authentication Helpers Contains interface (MultiDomainBasicAuth) and associated glue code for providing credentials in the context of network requests. """ import os import shutil import subprocess import urllib.parse from abc import ABC, abstractmethod from typing import Any, Dict, List, NamedTuple, Optional, Tuple from pip._vendor.requests.auth import AuthBase, HTTPBasicAuth from pip._vendor.requests.models import Request, Response from pip._vendor.requests.utils import get_netrc_auth from pip._internal.utils.logging import getLogger from pip._internal.utils.misc import ( ask, ask_input, ask_password, remove_auth_from_url, split_auth_netloc_from_url, ) from pip._internal.vcs.versioncontrol import AuthInfo logger = getLogger(__name__) KEYRING_DISABLED = False class Credentials(NamedTuple): url: str username: str password: str class KeyRingBaseProvider(ABC): """Keyring base provider interface""" @abstractmethod def get_auth_info(self, url: str, username: Optional[str]) -> Optional[AuthInfo]: ... @abstractmethod def save_auth_info(self, url: str, username: str, password: str) -> None: ... class KeyRingNullProvider(KeyRingBaseProvider): """Keyring null provider""" def get_auth_info(self, url: str, username: Optional[str]) -> Optional[AuthInfo]: return None def save_auth_info(self, url: str, username: str, password: str) -> None: return None class KeyRingPythonProvider(KeyRingBaseProvider): """Keyring interface which uses locally imported `keyring`""" def __init__(self) -> None: import keyring self.keyring = keyring def get_auth_info(self, url: str, username: Optional[str]) -> Optional[AuthInfo]: # Support keyring's get_credential interface which supports getting # credentials without a username. This is only available for # keyring>=15.2.0. if hasattr(self.keyring, "get_credential"): logger.debug("Getting credentials from keyring for %s", url) cred = self.keyring.get_credential(url, username) if cred is not None: return cred.username, cred.password return None if username is not None: logger.debug("Getting password from keyring for %s", url) password = self.keyring.get_password(url, username) if password: return username, password return None def save_auth_info(self, url: str, username: str, password: str) -> None: self.keyring.set_password(url, username, password) class KeyRingCliProvider(KeyRingBaseProvider): """Provider which uses `keyring` cli Instead of calling the keyring package installed alongside pip we call keyring on the command line which will enable pip to use which ever installation of keyring is available first in PATH. """ def __init__(self, cmd: str) -> None: self.keyring = cmd def get_auth_info(self, url: str, username: Optional[str]) -> Optional[AuthInfo]: # This is the default implementation of keyring.get_credential # https://github.com/jaraco/keyring/blob/97689324abcf01bd1793d49063e7ca01e03d7d07/keyring/backend.py#L134-L139 if username is not None: password = self._get_password(url, username) if password is not None: return username, password return None def save_auth_info(self, url: str, username: str, password: str) -> None: return self._set_password(url, username, password) def _get_password(self, service_name: str, username: str) -> Optional[str]: """Mirror the implementation of keyring.get_password using cli""" if self.keyring is None: return None cmd = [self.keyring, "get", service_name, username] env = os.environ.copy() env["PYTHONIOENCODING"] = "utf-8" res = subprocess.run( cmd, stdin=subprocess.DEVNULL, capture_output=True, env=env, ) if res.returncode: return None return res.stdout.decode("utf-8").strip(os.linesep) def _set_password(self, service_name: str, username: str, password: str) -> None: """Mirror the implementation of keyring.set_password using cli""" if self.keyring is None: return None cmd = [self.keyring, "set", service_name, username] input_ = (password + os.linesep).encode("utf-8") env = os.environ.copy() env["PYTHONIOENCODING"] = "utf-8" res = subprocess.run(cmd, input=input_, env=env) res.check_returncode() return None def get_keyring_provider() -> KeyRingBaseProvider: # keyring has previously failed and been disabled if not KEYRING_DISABLED: # Default to trying to use Python provider try: return KeyRingPythonProvider() except ImportError: pass except Exception as exc: # In the event of an unexpected exception # we should warn the user logger.warning( "Installed copy of keyring fails with exception %s, " "trying to find a keyring executable as a fallback", str(exc), ) # Fallback to Cli Provider if `keyring` isn't installed cli = shutil.which("keyring") if cli: return KeyRingCliProvider(cli) return KeyRingNullProvider() def get_keyring_auth(url: Optional[str], username: Optional[str]) -> Optional[AuthInfo]: """Return the tuple auth for a given url from keyring.""" # Do nothing if no url was provided if not url: return None keyring = get_keyring_provider() try: return keyring.get_auth_info(url, username) except Exception as exc: logger.warning( "Keyring is skipped due to an exception: %s", str(exc), ) global KEYRING_DISABLED KEYRING_DISABLED = True return None class MultiDomainBasicAuth(AuthBase): def __init__( self, prompting: bool = True, index_urls: Optional[List[str]] = None ) -> None: self.prompting = prompting self.index_urls = index_urls self.passwords: Dict[str, AuthInfo] = {} # When the user is prompted to enter credentials and keyring is # available, we will offer to save them. If the user accepts, # this value is set to the credentials they entered. After the # request authenticates, the caller should call # ``save_credentials`` to save these. self._credentials_to_save: Optional[Credentials] = None def _get_index_url(self, url: str) -> Optional[str]: """Return the original index URL matching the requested URL. Cached or dynamically generated credentials may work against the original index URL rather than just the netloc. The provided url should have had its username and password removed already. If the original index url had credentials then they will be included in the return value. Returns None if no matching index was found, or if --no-index was specified by the user. """ if not url or not self.index_urls: return None for u in self.index_urls: prefix = remove_auth_from_url(u).rstrip("/") + "/" if url.startswith(prefix): return u return None def _get_new_credentials( self, original_url: str, allow_netrc: bool = True, allow_keyring: bool = False, ) -> AuthInfo: """Find and return credentials for the specified URL.""" # Split the credentials and netloc from the url. url, netloc, url_user_password = split_auth_netloc_from_url( original_url, ) # Start with the credentials embedded in the url username, password = url_user_password if username is not None and password is not None: logger.debug("Found credentials in url for %s", netloc) return url_user_password # Find a matching index url for this request index_url = self._get_index_url(url) if index_url: # Split the credentials from the url. index_info = split_auth_netloc_from_url(index_url) if index_info: index_url, _, index_url_user_password = index_info logger.debug("Found index url %s", index_url) # If an index URL was found, try its embedded credentials if index_url and index_url_user_password[0] is not None: username, password = index_url_user_password if username is not None and password is not None: logger.debug("Found credentials in index url for %s", netloc) return index_url_user_password # Get creds from netrc if we still don't have them if allow_netrc: netrc_auth = get_netrc_auth(original_url) if netrc_auth: logger.debug("Found credentials in netrc for %s", netloc) return netrc_auth # If we don't have a password and keyring is available, use it. if allow_keyring: # The index url is more specific than the netloc, so try it first # fmt: off kr_auth = ( get_keyring_auth(index_url, username) or get_keyring_auth(netloc, username) ) # fmt: on if kr_auth: logger.debug("Found credentials in keyring for %s", netloc) return kr_auth return username, password def _get_url_and_credentials( self, original_url: str ) -> Tuple[str, Optional[str], Optional[str]]: """Return the credentials to use for the provided URL. If allowed, netrc and keyring may be used to obtain the correct credentials. Returns (url_without_credentials, username, password). Note that even if the original URL contains credentials, this function may return a different username and password. """ url, netloc, _ = split_auth_netloc_from_url(original_url) # Try to get credentials from original url username, password = self._get_new_credentials(original_url) # If credentials not found, use any stored credentials for this netloc. # Do this if either the username or the password is missing. # This accounts for the situation in which the user has specified # the username in the index url, but the password comes from keyring. if (username is None or password is None) and netloc in self.passwords: un, pw = self.passwords[netloc] # It is possible that the cached credentials are for a different username, # in which case the cache should be ignored. if username is None or username == un: username, password = un, pw if username is not None or password is not None: # Convert the username and password if they're None, so that # this netloc will show up as "cached" in the conditional above. # Further, HTTPBasicAuth doesn't accept None, so it makes sense to # cache the value that is going to be used. username = username or "" password = password or "" # Store any acquired credentials. self.passwords[netloc] = (username, password) assert ( # Credentials were found (username is not None and password is not None) # Credentials were not found or (username is None and password is None) ), f"Could not load credentials from url: {original_url}" return url, username, password def __call__(self, req: Request) -> Request: # Get credentials for this request url, username, password = self._get_url_and_credentials(req.url) # Set the url of the request to the url without any credentials req.url = url if username is not None and password is not None: # Send the basic auth with this request req = HTTPBasicAuth(username, password)(req) # Attach a hook to handle 401 responses req.register_hook("response", self.handle_401) return req # Factored out to allow for easy patching in tests def _prompt_for_password( self, netloc: str ) -> Tuple[Optional[str], Optional[str], bool]: username = ask_input(f"User for {netloc}: ") if not username: return None, None, False auth = get_keyring_auth(netloc, username) if auth and auth[0] is not None and auth[1] is not None: return auth[0], auth[1], False password = ask_password("Password: ") return username, password, True # Factored out to allow for easy patching in tests def _should_save_password_to_keyring(self) -> bool: if get_keyring_provider() is None: return False return ask("Save credentials to keyring [y/N]: ", ["y", "n"]) == "y" def handle_401(self, resp: Response, **kwargs: Any) -> Response: # We only care about 401 responses, anything else we want to just # pass through the actual response if resp.status_code != 401: return resp # We are not able to prompt the user so simply return the response if not self.prompting: return resp parsed = urllib.parse.urlparse(resp.url) # Query the keyring for credentials: username, password = self._get_new_credentials( resp.url, allow_netrc=False, allow_keyring=True, ) # Prompt the user for a new username and password save = False if not username and not password: username, password, save = self._prompt_for_password(parsed.netloc) # Store the new username and password to use for future requests self._credentials_to_save = None if username is not None and password is not None: self.passwords[parsed.netloc] = (username, password) # Prompt to save the password to keyring if save and self._should_save_password_to_keyring(): self._credentials_to_save = Credentials( url=parsed.netloc, username=username, password=password, ) # Consume content and release the original connection to allow our new # request to reuse the same one. resp.content resp.raw.release_conn() # Add our new username and password to the request req = HTTPBasicAuth(username or "", password or "")(resp.request) req.register_hook("response", self.warn_on_401) # On successful request, save the credentials that were used to # keyring. (Note that if the user responded "no" above, this member # is not set and nothing will be saved.) if self._credentials_to_save: req.register_hook("response", self.save_credentials) # Send our new request new_resp = resp.connection.send(req, **kwargs) new_resp.history.append(resp) return new_resp def warn_on_401(self, resp: Response, **kwargs: Any) -> None: """Response callback to warn about incorrect credentials.""" if resp.status_code == 401: logger.warning( "401 Error, Credentials not correct for %s", resp.request.url, ) def save_credentials(self, resp: Response, **kwargs: Any) -> None: """Response callback to save credentials on success.""" keyring = get_keyring_provider() assert not isinstance( keyring, KeyRingNullProvider ), "should never reach here without keyring" creds = self._credentials_to_save self._credentials_to_save = None if creds and resp.status_code < 400: try: logger.info("Saving credentials to keyring") keyring.save_auth_info(creds.url, creds.username, creds.password) except Exception: logger.exception("Failed to save credentials")