synapse-product/synapse/util/threepids.py
Patrick Cloke d8cc86eff4
Remove redundant types from comments. ()
Remove type hints from comments which have been added
as Python type hints. This helps avoid drift between comments
and reality, as well as removing redundant information.

Also adds some missing type hints which were simple to fill in.
2022-11-16 15:25:24 +00:00

118 lines
3.6 KiB
Python

# Copyright 2018 New Vector Ltd
#
# 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.
import logging
import re
import typing
if typing.TYPE_CHECKING:
from synapse.server import HomeServer
logger = logging.getLogger(__name__)
# it's unclear what the maximum length of an email address is. RFC3696 (as corrected
# by errata) says:
# the upper limit on address lengths should normally be considered to be 254.
#
# In practice, mail servers appear to be more tolerant and allow 400 characters
# or so. Let's allow 500, which should be plenty for everyone.
#
MAX_EMAIL_ADDRESS_LENGTH = 500
async def check_3pid_allowed(
hs: "HomeServer",
medium: str,
address: str,
registration: bool = False,
) -> bool:
"""Checks whether a given format of 3PID is allowed to be used on this HS
Args:
hs: server
medium: 3pid medium - e.g. email, msisdn
address: address within that medium (e.g. "wotan@matrix.org")
msisdns need to first have been canonicalised
registration: whether we want to bind the 3PID as part of registering a new user.
Returns:
whether the 3PID medium/address is allowed to be added to this HS
"""
if not await hs.get_password_auth_provider().is_3pid_allowed(
medium, address, registration
):
return False
if hs.config.registration.allowed_local_3pids:
for constraint in hs.config.registration.allowed_local_3pids:
logger.debug(
"Checking 3PID %s (%s) against %s (%s)",
address,
medium,
constraint["pattern"],
constraint["medium"],
)
if medium == constraint["medium"] and re.match(
constraint["pattern"], address
):
return True
else:
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()
def validate_email(address: str) -> str:
"""Does some basic validation on an email address.
Returns the canonicalised email, as returned by `canonicalise_email`.
Raises a ValueError if the email is invalid.
"""
# First we try canonicalising in case that fails
address = canonicalise_email(address)
# Email addresses have to be at least 3 characters.
if len(address) < 3:
raise ValueError("Unable to parse email address")
if len(address) > MAX_EMAIL_ADDRESS_LENGTH:
raise ValueError("Unable to parse email address")
return address