From 21a212f8e50343e9b55944fa75ece7911fd2cb70 Mon Sep 17 00:00:00 2001 From: Dirk Klimpel <5740567+dklimpel@users.noreply.github.com> Date: Fri, 3 Jul 2020 15:03:13 +0200 Subject: [PATCH] Fix inconsistent handling of upper and lower cases of email addresses. (#7021) fixes #7016 --- changelog.d/7021.bugfix | 1 + synapse/handlers/auth.py | 5 +- synapse/rest/client/v1/login.py | 12 +- synapse/rest/client/v2_alpha/account.py | 40 ++++- synapse/rest/client/v2_alpha/register.py | 22 ++- synapse/util/threepids.py | 23 +++ tests/rest/client/v2_alpha/test_account.py | 181 +++++++++++++++++---- tests/util/test_threepids.py | 49 ++++++ 8 files changed, 282 insertions(+), 51 deletions(-) create mode 100644 changelog.d/7021.bugfix create mode 100644 tests/util/test_threepids.py diff --git a/changelog.d/7021.bugfix b/changelog.d/7021.bugfix new file mode 100644 index 000000000..140fe37b2 --- /dev/null +++ b/changelog.d/7021.bugfix @@ -0,0 +1 @@ +Fix inconsistent handling of upper and lower case in email addresses when used as identifiers for login, etc. Contributed by @dklimpel. diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py index c3f86e741..d713a06bf 100644 --- a/synapse/handlers/auth.py +++ b/synapse/handlers/auth.py @@ -45,6 +45,7 @@ from synapse.metrics.background_process_metrics import run_as_background_process from synapse.module_api import ModuleApi from synapse.push.mailer import load_jinja2_templates from synapse.types import Requester, UserID +from synapse.util.threepids import canonicalise_email from ._base import BaseHandler @@ -928,7 +929,7 @@ class AuthHandler(BaseHandler): # for the presence of an email address during password reset was # case sensitive). if medium == "email": - address = address.lower() + address = canonicalise_email(address) await self.store.user_add_threepid( user_id, medium, address, validated_at, self.hs.get_clock().time_msec() @@ -956,7 +957,7 @@ class AuthHandler(BaseHandler): # 'Canonicalise' email addresses as per above if medium == "email": - address = address.lower() + address = canonicalise_email(address) identity_handler = self.hs.get_handlers().identity_handler result = await identity_handler.try_unbind_threepid( diff --git a/synapse/rest/client/v1/login.py b/synapse/rest/client/v1/login.py index bf0f9bd07..f6eef7afe 100644 --- a/synapse/rest/client/v1/login.py +++ b/synapse/rest/client/v1/login.py @@ -28,6 +28,7 @@ from synapse.rest.client.v2_alpha._base import client_patterns from synapse.rest.well_known import WellKnownBuilder from synapse.types import UserID from synapse.util.msisdn import phone_number_to_msisdn +from synapse.util.threepids import canonicalise_email logger = logging.getLogger(__name__) @@ -206,11 +207,14 @@ class LoginRestServlet(RestServlet): if medium is None or address is None: raise SynapseError(400, "Invalid thirdparty identifier") + # For emails, canonicalise the address. + # We store all email addresses canonicalised in the DB. + # (See add_threepid in synapse/handlers/auth.py) if medium == "email": - # For emails, transform the address to lowercase. - # We store all email addreses as lowercase in the DB. - # (See add_threepid in synapse/handlers/auth.py) - address = address.lower() + try: + address = canonicalise_email(address) + except ValueError as e: + raise SynapseError(400, str(e)) # We also apply account rate limiting using the 3PID as a key, as # otherwise using 3PID bypasses the ratelimiting based on user ID. diff --git a/synapse/rest/client/v2_alpha/account.py b/synapse/rest/client/v2_alpha/account.py index 182a308ee..3767a809a 100644 --- a/synapse/rest/client/v2_alpha/account.py +++ b/synapse/rest/client/v2_alpha/account.py @@ -30,7 +30,7 @@ from synapse.http.servlet import ( from synapse.push.mailer import Mailer, load_jinja2_templates from synapse.util.msisdn import phone_number_to_msisdn from synapse.util.stringutils import assert_valid_client_secret, random_string -from synapse.util.threepids import check_3pid_allowed +from synapse.util.threepids import canonicalise_email, check_3pid_allowed from ._base import client_patterns, interactive_auth_handler @@ -83,7 +83,15 @@ class EmailPasswordRequestTokenRestServlet(RestServlet): client_secret = body["client_secret"] assert_valid_client_secret(client_secret) - email = body["email"] + # Canonicalise the email address. The addresses are all stored canonicalised + # in the database. This allows the user to reset his password without having to + # know the exact spelling (eg. upper and lower case) of address in the database. + # Stored in the database "foo@bar.com" + # User requests with "FOO@bar.com" would raise a Not Found error + try: + email = canonicalise_email(body["email"]) + except ValueError as e: + raise SynapseError(400, str(e)) send_attempt = body["send_attempt"] next_link = body.get("next_link") # Optional param @@ -94,6 +102,10 @@ class EmailPasswordRequestTokenRestServlet(RestServlet): Codes.THREEPID_DENIED, ) + # The email will be sent to the stored address. + # This avoids a potential account hijack by requesting a password reset to + # an email address which is controlled by the attacker but which, after + # canonicalisation, matches the one in our database. existing_user_id = await self.hs.get_datastore().get_user_id_by_threepid( "email", email ) @@ -274,10 +286,13 @@ class PasswordRestServlet(RestServlet): if "medium" not in threepid or "address" not in threepid: raise SynapseError(500, "Malformed threepid") if threepid["medium"] == "email": - # For emails, transform the address to lowercase. - # We store all email addreses as lowercase in the DB. + # For emails, canonicalise the address. + # We store all email addresses canonicalised in the DB. # (See add_threepid in synapse/handlers/auth.py) - threepid["address"] = threepid["address"].lower() + try: + threepid["address"] = canonicalise_email(threepid["address"]) + except ValueError as e: + raise SynapseError(400, str(e)) # if using email, we must know about the email they're authing with! threepid_user_id = await self.datastore.get_user_id_by_threepid( threepid["medium"], threepid["address"] @@ -392,7 +407,16 @@ class EmailThreepidRequestTokenRestServlet(RestServlet): client_secret = body["client_secret"] assert_valid_client_secret(client_secret) - email = body["email"] + # Canonicalise the email address. The addresses are all stored canonicalised + # in the database. + # This ensures that the validation email is sent to the canonicalised address + # as it will later be entered into the database. + # Otherwise the email will be sent to "FOO@bar.com" and stored as + # "foo@bar.com" in database. + try: + email = canonicalise_email(body["email"]) + except ValueError as e: + raise SynapseError(400, str(e)) send_attempt = body["send_attempt"] next_link = body.get("next_link") # Optional param @@ -403,9 +427,7 @@ class EmailThreepidRequestTokenRestServlet(RestServlet): Codes.THREEPID_DENIED, ) - existing_user_id = await self.store.get_user_id_by_threepid( - "email", body["email"] - ) + existing_user_id = await self.store.get_user_id_by_threepid("email", email) if existing_user_id is not None: if self.config.request_token_inhibit_3pid_errors: diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py index 56a451c42..370742ce5 100644 --- a/synapse/rest/client/v2_alpha/register.py +++ b/synapse/rest/client/v2_alpha/register.py @@ -47,7 +47,7 @@ from synapse.push.mailer import load_jinja2_templates from synapse.util.msisdn import phone_number_to_msisdn from synapse.util.ratelimitutils import FederationRateLimiter from synapse.util.stringutils import assert_valid_client_secret, random_string -from synapse.util.threepids import check_3pid_allowed +from synapse.util.threepids import canonicalise_email, check_3pid_allowed from ._base import client_patterns, interactive_auth_handler @@ -116,7 +116,14 @@ class EmailRegisterRequestTokenRestServlet(RestServlet): client_secret = body["client_secret"] assert_valid_client_secret(client_secret) - email = body["email"] + # For emails, canonicalise the address. + # We store all email addresses canonicalised in the DB. + # (See on_POST in EmailThreepidRequestTokenRestServlet + # in synapse/rest/client/v2_alpha/account.py) + try: + email = canonicalise_email(body["email"]) + except ValueError as e: + raise SynapseError(400, str(e)) send_attempt = body["send_attempt"] next_link = body.get("next_link") # Optional param @@ -128,7 +135,7 @@ class EmailRegisterRequestTokenRestServlet(RestServlet): ) existing_user_id = await self.hs.get_datastore().get_user_id_by_threepid( - "email", body["email"] + "email", email ) if existing_user_id is not None: @@ -552,6 +559,15 @@ class RegisterRestServlet(RestServlet): if login_type in auth_result: medium = auth_result[login_type]["medium"] address = auth_result[login_type]["address"] + # For emails, canonicalise the address. + # We store all email addresses canonicalised in the DB. + # (See on_POST in EmailThreepidRequestTokenRestServlet + # in synapse/rest/client/v2_alpha/account.py) + if medium == "email": + try: + address = canonicalise_email(address) + except ValueError as e: + raise SynapseError(400, str(e)) existing_user_id = await self.store.get_user_id_by_threepid( medium, address diff --git a/synapse/util/threepids.py b/synapse/util/threepids.py index 3ec1dfb0c..43c2e0ac2 100644 --- a/synapse/util/threepids.py +++ b/synapse/util/threepids.py @@ -48,3 +48,26 @@ def check_3pid_allowed(hs, medium, address): return True return False + + +def canonicalise_email(address: str) -> str: + """'Canonicalise' email address + Case folding of local part of email address and lowercase domain part + See MSC2265, https://github.com/matrix-org/matrix-doc/pull/2265 + + Args: + address: email address to be canonicalised + Returns: + The canonical form of the email address + Raises: + ValueError if the address could not be parsed. + """ + + address = address.strip() + + parts = address.split("@") + if len(parts) != 2: + logger.debug("Couldn't parse email address %s", address) + raise ValueError("Unable to parse email address") + + return parts[0].casefold() + "@" + parts[1].lower() diff --git a/tests/rest/client/v2_alpha/test_account.py b/tests/rest/client/v2_alpha/test_account.py index 3ab611f61..152a5182f 100644 --- a/tests/rest/client/v2_alpha/test_account.py +++ b/tests/rest/client/v2_alpha/test_account.py @@ -108,6 +108,46 @@ class PasswordResetTestCase(unittest.HomeserverTestCase): # Assert we can't log in with the old password self.attempt_wrong_password_login("kermit", old_password) + def test_basic_password_reset_canonicalise_email(self): + """Test basic password reset flow + Request password reset with different spelling + """ + old_password = "monkey" + new_password = "kangeroo" + + user_id = self.register_user("kermit", old_password) + self.login("kermit", old_password) + + email_profile = "test@example.com" + email_passwort_reset = "TEST@EXAMPLE.COM" + + # Add a threepid + self.get_success( + self.store.user_add_threepid( + user_id=user_id, + medium="email", + address=email_profile, + validated_at=0, + added_at=0, + ) + ) + + client_secret = "foobar" + session_id = self._request_token(email_passwort_reset, client_secret) + + self.assertEquals(len(self.email_attempts), 1) + link = self._get_link_from_email() + + self._validate_token(link) + + self._reset_password(new_password, session_id, client_secret) + + # Assert we can log in with the new password + self.login("kermit", new_password) + + # Assert we can't log in with the old password + self.attempt_wrong_password_login("kermit", old_password) + def test_cant_reset_password_without_clicking_link(self): """Test that we do actually need to click the link in the email """ @@ -386,44 +426,67 @@ class ThreepidEmailRestTestCase(unittest.HomeserverTestCase): self.email = "test@example.com" self.url_3pid = b"account/3pid" - def test_add_email(self): - """Test adding an email to profile - """ - client_secret = "foobar" - session_id = self._request_token(self.email, client_secret) + def test_add_valid_email(self): + self.get_success(self._add_email(self.email, self.email)) - self.assertEquals(len(self.email_attempts), 1) - link = self._get_link_from_email() - - self._validate_token(link) - - request, channel = self.make_request( - "POST", - b"/_matrix/client/unstable/account/3pid/add", - { - "client_secret": client_secret, - "sid": session_id, - "auth": { - "type": "m.login.password", - "user": self.user_id, - "password": "test", - }, - }, - access_token=self.user_id_tok, + def test_add_valid_email_second_time(self): + self.get_success(self._add_email(self.email, self.email)) + self.get_success( + self._request_token_invalid_email( + self.email, + expected_errcode=Codes.THREEPID_IN_USE, + expected_error="Email is already in use", + ) ) - self.render(request) - self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"]) - - # Get user - request, channel = self.make_request( - "GET", self.url_3pid, access_token=self.user_id_tok, + def test_add_valid_email_second_time_canonicalise(self): + self.get_success(self._add_email(self.email, self.email)) + self.get_success( + self._request_token_invalid_email( + "TEST@EXAMPLE.COM", + expected_errcode=Codes.THREEPID_IN_USE, + expected_error="Email is already in use", + ) ) - self.render(request) - self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"]) - self.assertEqual("email", channel.json_body["threepids"][0]["medium"]) - self.assertEqual(self.email, channel.json_body["threepids"][0]["address"]) + def test_add_email_no_at(self): + self.get_success( + self._request_token_invalid_email( + "address-without-at.bar", + expected_errcode=Codes.UNKNOWN, + expected_error="Unable to parse email address", + ) + ) + + def test_add_email_two_at(self): + self.get_success( + self._request_token_invalid_email( + "foo@foo@test.bar", + expected_errcode=Codes.UNKNOWN, + expected_error="Unable to parse email address", + ) + ) + + def test_add_email_bad_format(self): + self.get_success( + self._request_token_invalid_email( + "user@bad.example.net@good.example.com", + expected_errcode=Codes.UNKNOWN, + expected_error="Unable to parse email address", + ) + ) + + def test_add_email_domain_to_lower(self): + self.get_success(self._add_email("foo@TEST.BAR", "foo@test.bar")) + + def test_add_email_domain_with_umlaut(self): + self.get_success(self._add_email("foo@Öumlaut.com", "foo@öumlaut.com")) + + def test_add_email_address_casefold(self): + self.get_success(self._add_email("Strauß@Example.com", "strauss@example.com")) + + def test_address_trim(self): + self.get_success(self._add_email(" foo@test.bar ", "foo@test.bar")) def test_add_email_if_disabled(self): """Test adding email to profile when doing so is disallowed @@ -616,6 +679,19 @@ class ThreepidEmailRestTestCase(unittest.HomeserverTestCase): return channel.json_body["sid"] + def _request_token_invalid_email( + self, email, expected_errcode, expected_error, client_secret="foobar", + ): + request, channel = self.make_request( + "POST", + b"account/3pid/email/requestToken", + {"client_secret": client_secret, "email": email, "send_attempt": 1}, + ) + self.render(request) + self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"]) + self.assertEqual(expected_errcode, channel.json_body["errcode"]) + self.assertEqual(expected_error, channel.json_body["error"]) + def _validate_token(self, link): # Remove the host path = link.replace("https://example.com", "") @@ -643,3 +719,42 @@ class ThreepidEmailRestTestCase(unittest.HomeserverTestCase): assert match, "Could not find link in email" return match.group(0) + + def _add_email(self, request_email, expected_email): + """Test adding an email to profile + """ + client_secret = "foobar" + session_id = self._request_token(request_email, client_secret) + + self.assertEquals(len(self.email_attempts), 1) + link = self._get_link_from_email() + + self._validate_token(link) + + request, channel = self.make_request( + "POST", + b"/_matrix/client/unstable/account/3pid/add", + { + "client_secret": client_secret, + "sid": session_id, + "auth": { + "type": "m.login.password", + "user": self.user_id, + "password": "test", + }, + }, + access_token=self.user_id_tok, + ) + + self.render(request) + self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"]) + + # Get user + request, channel = self.make_request( + "GET", self.url_3pid, access_token=self.user_id_tok, + ) + self.render(request) + + self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"]) + self.assertEqual("email", channel.json_body["threepids"][0]["medium"]) + self.assertEqual(expected_email, channel.json_body["threepids"][0]["address"]) diff --git a/tests/util/test_threepids.py b/tests/util/test_threepids.py new file mode 100644 index 000000000..5513724d8 --- /dev/null +++ b/tests/util/test_threepids.py @@ -0,0 +1,49 @@ +# -*- coding: utf-8 -*- +# Copyright 2020 Dirk Klimpel +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +from synapse.util.threepids import canonicalise_email + +from tests.unittest import HomeserverTestCase + + +class CanonicaliseEmailTests(HomeserverTestCase): + def test_no_at(self): + with self.assertRaises(ValueError): + canonicalise_email("address-without-at.bar") + + def test_two_at(self): + with self.assertRaises(ValueError): + canonicalise_email("foo@foo@test.bar") + + def test_bad_format(self): + with self.assertRaises(ValueError): + canonicalise_email("user@bad.example.net@good.example.com") + + def test_valid_format(self): + self.assertEqual(canonicalise_email("foo@test.bar"), "foo@test.bar") + + def test_domain_to_lower(self): + self.assertEqual(canonicalise_email("foo@TEST.BAR"), "foo@test.bar") + + def test_domain_with_umlaut(self): + self.assertEqual(canonicalise_email("foo@Öumlaut.com"), "foo@öumlaut.com") + + def test_address_casefold(self): + self.assertEqual( + canonicalise_email("Strauß@Example.com"), "strauss@example.com" + ) + + def test_address_trim(self): + self.assertEqual(canonicalise_email(" foo@test.bar "), "foo@test.bar")