diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index 71a955b281..df788230fa 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -23,6 +23,7 @@ from synapse.util.logutils import log_function
from synapse.types import UserID, EventID
import logging
+import pymacaroons
logger = logging.getLogger(__name__)
@@ -40,6 +41,12 @@ class Auth(object):
self.store = hs.get_datastore()
self.state = hs.get_state_handler()
self.TOKEN_NOT_FOUND_HTTP_STATUS = 401
+ self._KNOWN_CAVEAT_PREFIXES = set([
+ "gen = ",
+ "type = ",
+ "time < ",
+ "user_id = ",
+ ])
def check(self, event, auth_events):
""" Checks if this event is correctly authed.
@@ -367,7 +374,7 @@ class Auth(object):
except KeyError:
pass # normal users won't have the user_id query parameter set.
- user_info = yield self.get_user_by_access_token(access_token)
+ user_info = yield self._get_user_by_access_token(access_token)
user = user_info["user"]
token_id = user_info["token_id"]
@@ -394,7 +401,7 @@ class Auth(object):
)
@defer.inlineCallbacks
- def get_user_by_access_token(self, token):
+ def _get_user_by_access_token(self, token):
""" Get a registered user's ID.
Args:
@@ -404,6 +411,86 @@ class Auth(object):
Raises:
AuthError if no user by that token exists or the token is invalid.
"""
+ try:
+ ret = yield self._get_user_from_macaroon(token)
+ except AuthError:
+ # TODO(daniel): Remove this fallback when all existing access tokens
+ # have been re-issued as macaroons.
+ ret = yield self._look_up_user_by_access_token(token)
+ defer.returnValue(ret)
+
+ @defer.inlineCallbacks
+ def _get_user_from_macaroon(self, macaroon_str):
+ try:
+ macaroon = pymacaroons.Macaroon.deserialize(macaroon_str)
+ self._validate_macaroon(macaroon)
+
+ user_prefix = "user_id = "
+ for caveat in macaroon.caveats:
+ if caveat.caveat_id.startswith(user_prefix):
+ user = UserID.from_string(caveat.caveat_id[len(user_prefix):])
+ # This codepath exists so that we can actually return a
+ # token ID, because we use token IDs in place of device
+ # identifiers throughout the codebase.
+ # TODO(daniel): Remove this fallback when device IDs are
+ # properly implemented.
+ ret = yield self._look_up_user_by_access_token(macaroon_str)
+ if ret["user"] != user:
+ logger.error(
+ "Macaroon user (%s) != DB user (%s)",
+ user,
+ ret["user"]
+ )
+ raise AuthError(
+ self.TOKEN_NOT_FOUND_HTTP_STATUS,
+ "User mismatch in macaroon",
+ errcode=Codes.UNKNOWN_TOKEN
+ )
+ defer.returnValue(ret)
+ raise AuthError(
+ self.TOKEN_NOT_FOUND_HTTP_STATUS, "No user caveat in macaroon",
+ errcode=Codes.UNKNOWN_TOKEN
+ )
+ except (pymacaroons.exceptions.MacaroonException, TypeError, ValueError):
+ raise AuthError(
+ self.TOKEN_NOT_FOUND_HTTP_STATUS, "Invalid macaroon passed.",
+ errcode=Codes.UNKNOWN_TOKEN
+ )
+
+ def _validate_macaroon(self, macaroon):
+ v = pymacaroons.Verifier()
+ v.satisfy_exact("gen = 1")
+ v.satisfy_exact("type = access")
+ v.satisfy_general(lambda c: c.startswith("user_id = "))
+ v.satisfy_general(self._verify_expiry)
+ v.verify(macaroon, self.hs.config.macaroon_secret_key)
+
+ v = pymacaroons.Verifier()
+ v.satisfy_general(self._verify_recognizes_caveats)
+ v.verify(macaroon, self.hs.config.macaroon_secret_key)
+
+ def _verify_expiry(self, caveat):
+ prefix = "time < "
+ if not caveat.startswith(prefix):
+ return False
+ # TODO(daniel): Enable expiry check when clients actually know how to
+ # refresh tokens. (And remember to enable the tests)
+ return True
+ expiry = int(caveat[len(prefix):])
+ now = self.hs.get_clock().time_msec()
+ return now < expiry
+
+ def _verify_recognizes_caveats(self, caveat):
+ first_space = caveat.find(" ")
+ if first_space < 0:
+ return False
+ second_space = caveat.find(" ", first_space + 1)
+ if second_space < 0:
+ return False
+ return caveat[:second_space + 1] in self._KNOWN_CAVEAT_PREFIXES
+
+ @defer.inlineCallbacks
+ def _look_up_user_by_access_token(self, token):
ret = yield self.store.get_user_by_access_token(token)
if not ret:
raise AuthError(
@@ -414,7 +501,6 @@ class Auth(object):
"user": UserID.from_string(ret.get("name")),
"token_id": ret.get("token_id", None),
}
-
defer.returnValue(user_info)
@defer.inlineCallbacks
|
