* remove TO header if it's set to "undisclosed-recipients:;" more info on https://www.rfc-editor.org/rfc/rfc4356.txt * remove unnecessary indentation character in plain text email
2333 lines
78 KiB
Python
2333 lines
78 KiB
Python
"""
|
|
Handle the email *forward* and *reply*. phase. There are 3 actors:
|
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- contact: who sends emails to alias@sl.co address
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- SL email handler (this script)
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- user personal email: to be protected. Should never leak to contact.
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|
|
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This script makes sure that in the forward phase, the email that is forwarded to user personal email has the following
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envelope and header fields:
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Envelope:
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mail from: @contact
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rcpt to: @personal_email
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Header:
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From: @contact
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To: alias@sl.co # so user knows this email is sent to alias
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Reply-to: special@sl.co # magic HERE
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|
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And in the reply phase:
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Envelope:
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mail from: @contact
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rcpt to: @contact
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Header:
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From: alias@sl.co # so for contact the email comes from alias. magic HERE
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To: @contact
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The special@sl.co allows to hide user personal email when user clicks "Reply" to the forwarded email.
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It should contain the following info:
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- alias
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- @contact
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|
|
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"""
|
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import argparse
|
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import email
|
|
import time
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import uuid
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from email import encoders
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from email.encoders import encode_noop
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from email.message import Message
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from email.mime.application import MIMEApplication
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from email.mime.multipart import MIMEMultipart
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from email.utils import make_msgid, formatdate, getaddresses
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from io import BytesIO
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from smtplib import SMTPRecipientsRefused, SMTPServerDisconnected
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from typing import List, Tuple, Optional
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|
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import newrelic.agent
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from aiosmtpd.controller import Controller
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from aiosmtpd.smtp import Envelope
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from email_validator import validate_email, EmailNotValidError
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from flanker.addresslib import address
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from flanker.addresslib.address import EmailAddress
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from sqlalchemy.exc import IntegrityError
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from sqlalchemy.orm.exc import ObjectDeletedError
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|
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from app import pgp_utils, s3, config
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from app.alias_utils import try_auto_create
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from app.config import (
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EMAIL_DOMAIN,
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URL,
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UNSUBSCRIBER,
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LOAD_PGP_EMAIL_HANDLER,
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ENFORCE_SPF,
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ALERT_REVERSE_ALIAS_UNKNOWN_MAILBOX,
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ALERT_BOUNCE_EMAIL,
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ALERT_SPAM_EMAIL,
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|
SPAMASSASSIN_HOST,
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|
MAX_SPAM_SCORE,
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MAX_REPLY_PHASE_SPAM_SCORE,
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ALERT_SEND_EMAIL_CYCLE,
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ALERT_MAILBOX_IS_ALIAS,
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PGP_SENDER_PRIVATE_KEY,
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ALERT_BOUNCE_EMAIL_REPLY_PHASE,
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NOREPLY,
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BOUNCE_PREFIX,
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BOUNCE_SUFFIX,
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TRANSACTIONAL_BOUNCE_PREFIX,
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TRANSACTIONAL_BOUNCE_SUFFIX,
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ENABLE_SPAM_ASSASSIN,
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BOUNCE_PREFIX_FOR_REPLY_PHASE,
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POSTMASTER,
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OLD_UNSUBSCRIBER,
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ALERT_FROM_ADDRESS_IS_REVERSE_ALIAS,
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ALERT_TO_NOREPLY,
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)
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from app.db import Session
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from app.email import status, headers
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from app.email.rate_limit import rate_limited
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from app.email.spam import get_spam_score
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from app.email_utils import (
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send_email,
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add_dkim_signature,
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add_or_replace_header,
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delete_header,
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|
render,
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|
get_orig_message_from_bounce,
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|
delete_all_headers_except,
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|
get_spam_info,
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|
get_orig_message_from_spamassassin_report,
|
|
send_email_with_rate_control,
|
|
get_email_domain_part,
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|
copy,
|
|
send_email_at_most_times,
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|
is_valid_alias_address_domain,
|
|
should_add_dkim_signature,
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|
add_header,
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|
get_header_unicode,
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generate_reply_email,
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is_reverse_alias,
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normalize_reply_email,
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is_valid_email,
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replace,
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|
should_disable,
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|
parse_id_from_bounce,
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spf_pass,
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sanitize_header,
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get_queue_id,
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|
should_ignore_bounce,
|
|
parse_full_address,
|
|
get_mailbox_bounce_info,
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|
save_email_for_debugging,
|
|
save_envelope_for_debugging,
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get_verp_info_from_email,
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generate_verp_email,
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sl_formataddr,
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|
)
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from app.errors import (
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NonReverseAliasInReplyPhase,
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VERPTransactional,
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VERPForward,
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VERPReply,
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CannotCreateContactForReverseAlias,
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)
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from app.handler.dmarc import (
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apply_dmarc_policy_for_reply_phase,
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|
apply_dmarc_policy_for_forward_phase,
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)
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from app.handler.provider_complaint import (
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handle_hotmail_complaint,
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|
handle_yahoo_complaint,
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|
)
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|
from app.handler.spamd_result import (
|
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SpamdResult,
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|
SPFCheckResult,
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|
)
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from app.handler.unsubscribe_generator import UnsubscribeGenerator
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|
from app.handler.unsubscribe_handler import UnsubscribeHandler
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from app.log import LOG, set_message_id
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from app.mail_sender import sl_sendmail
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from app.message_utils import message_to_bytes
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from app.models import (
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Alias,
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Contact,
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BlockBehaviourEnum,
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EmailLog,
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User,
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RefusedEmail,
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|
Mailbox,
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|
Bounce,
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|
TransactionalEmail,
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|
IgnoredEmail,
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MessageIDMatching,
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Notification,
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VerpType,
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)
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from app.pgp_utils import (
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PGPException,
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|
sign_data_with_pgpy,
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sign_data,
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load_public_key_and_check,
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)
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from app.utils import sanitize_email
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from init_app import load_pgp_public_keys
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from server import create_light_app
|
|
|
|
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def get_or_create_contact(from_header: str, mail_from: str, alias: Alias) -> Contact:
|
|
"""
|
|
contact_from_header is the RFC 2047 format FROM header
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"""
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try:
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contact_name, contact_email = parse_full_address(from_header)
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except ValueError:
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contact_name, contact_email = "", ""
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if not is_valid_email(contact_email):
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# From header is wrongly formatted, try with mail_from
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if mail_from and mail_from != "<>":
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LOG.w(
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"Cannot parse email from from_header %s, use mail_from %s",
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from_header,
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mail_from,
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)
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contact_email = mail_from
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|
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if not is_valid_email(contact_email):
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LOG.w(
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"invalid contact email %s. Parse from %s %s",
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contact_email,
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from_header,
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mail_from,
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)
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# either reuse a contact with empty email or create a new contact with empty email
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contact_email = ""
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contact_email = sanitize_email(contact_email, not_lower=True)
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|
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if contact_name and "\x00" in contact_name:
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LOG.w("issue with contact name %s", contact_name)
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contact_name = ""
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contact = Contact.get_by(alias_id=alias.id, website_email=contact_email)
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if contact:
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if contact.name != contact_name:
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LOG.d(
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"Update contact %s name %s to %s",
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contact,
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contact.name,
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contact_name,
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)
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contact.name = contact_name
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Session.commit()
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# contact created in the past does not have mail_from and from_header field
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if not contact.mail_from and mail_from:
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LOG.d(
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"Set contact mail_from %s: %s to %s",
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contact,
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contact.mail_from,
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mail_from,
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)
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contact.mail_from = mail_from
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Session.commit()
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|
else:
|
|
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try:
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contact = Contact.create(
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user_id=alias.user_id,
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alias_id=alias.id,
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website_email=contact_email,
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name=contact_name,
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mail_from=mail_from,
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reply_email=generate_reply_email(contact_email, alias.user)
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if is_valid_email(contact_email)
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else NOREPLY,
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automatic_created=True,
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)
|
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if not contact_email:
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LOG.d("Create a contact with invalid email for %s", alias)
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contact.invalid_email = True
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|
|
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LOG.d(
|
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"create contact %s for %s, reverse alias:%s",
|
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contact_email,
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alias,
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contact.reply_email,
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|
)
|
|
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Session.commit()
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|
except IntegrityError:
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|
LOG.w("Contact %s %s already exist", alias, contact_email)
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Session.rollback()
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|
contact = Contact.get_by(alias_id=alias.id, website_email=contact_email)
|
|
|
|
return contact
|
|
|
|
|
|
def get_or_create_reply_to_contact(
|
|
reply_to_header: str, alias: Alias, msg: Message
|
|
) -> Optional[Contact]:
|
|
"""
|
|
Get or create the contact for the Reply-To header
|
|
"""
|
|
try:
|
|
contact_name, contact_address = parse_full_address(reply_to_header)
|
|
except ValueError:
|
|
return
|
|
|
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if not is_valid_email(contact_address):
|
|
LOG.w(
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|
"invalid reply-to address %s. Parse from %s",
|
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contact_address,
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reply_to_header,
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)
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return None
|
|
|
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contact = Contact.get_by(alias_id=alias.id, website_email=contact_address)
|
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if contact:
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return contact
|
|
else:
|
|
LOG.d(
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"create contact %s for alias %s via reply-to header %s",
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contact_address,
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alias,
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reply_to_header,
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)
|
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try:
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contact = Contact.create(
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user_id=alias.user_id,
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alias_id=alias.id,
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website_email=contact_address,
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name=contact_name,
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reply_email=generate_reply_email(contact_address, alias.user),
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automatic_created=True,
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)
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Session.commit()
|
|
except IntegrityError:
|
|
LOG.w("Contact %s %s already exist", alias, contact_address)
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|
Session.rollback()
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|
contact = Contact.get_by(alias_id=alias.id, website_email=contact_address)
|
|
|
|
return contact
|
|
|
|
|
|
def replace_header_when_forward(msg: Message, alias: Alias, header: str):
|
|
"""
|
|
Replace CC or To header by Reply emails in forward phase
|
|
"""
|
|
new_addrs: [str] = []
|
|
headers = msg.get_all(header, [])
|
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# headers can be an array of Header, convert it to string here
|
|
headers = [get_header_unicode(h) for h in headers]
|
|
|
|
full_addresses: [EmailAddress] = []
|
|
for h in headers:
|
|
full_addresses += address.parse_list(h)
|
|
|
|
for full_address in full_addresses:
|
|
contact_email = sanitize_email(full_address.address, not_lower=True)
|
|
|
|
# no transformation when alias is already in the header
|
|
if contact_email.lower() == alias.email:
|
|
new_addrs.append(full_address.full_spec())
|
|
continue
|
|
|
|
try:
|
|
# NOT allow unicode for contact address
|
|
validate_email(
|
|
contact_email, check_deliverability=False, allow_smtputf8=False
|
|
)
|
|
except EmailNotValidError:
|
|
LOG.w("invalid contact email %s. %s. Skip", contact_email, headers)
|
|
continue
|
|
|
|
contact = Contact.get_by(alias_id=alias.id, website_email=contact_email)
|
|
if contact:
|
|
# update the contact name if needed
|
|
if contact.name != full_address.display_name:
|
|
LOG.d(
|
|
"Update contact %s name %s to %s",
|
|
contact,
|
|
contact.name,
|
|
full_address.display_name,
|
|
)
|
|
contact.name = full_address.display_name
|
|
Session.commit()
|
|
else:
|
|
LOG.d(
|
|
"create contact for alias %s and email %s, header %s",
|
|
alias,
|
|
contact_email,
|
|
header,
|
|
)
|
|
|
|
try:
|
|
contact = Contact.create(
|
|
user_id=alias.user_id,
|
|
alias_id=alias.id,
|
|
website_email=contact_email,
|
|
name=full_address.display_name,
|
|
reply_email=generate_reply_email(contact_email, alias.user),
|
|
is_cc=header.lower() == "cc",
|
|
automatic_created=True,
|
|
)
|
|
Session.commit()
|
|
except IntegrityError:
|
|
LOG.w("Contact %s %s already exist", alias, contact_email)
|
|
Session.rollback()
|
|
contact = Contact.get_by(alias_id=alias.id, website_email=contact_email)
|
|
|
|
new_addrs.append(contact.new_addr())
|
|
|
|
if new_addrs:
|
|
new_header = ",".join(new_addrs)
|
|
LOG.d("Replace %s header, old: %s, new: %s", header, msg[header], new_header)
|
|
add_or_replace_header(msg, header, new_header)
|
|
else:
|
|
LOG.d("Delete %s header, old value %s", header, msg[header])
|
|
delete_header(msg, header)
|
|
|
|
|
|
def add_alias_to_header_if_needed(msg, alias):
|
|
"""
|
|
During the forward phase, add alias to To: header if it isn't included in To and Cc header
|
|
It can happen that the alias isn't included in To: and CC: header, for example if this is a BCC email
|
|
:return:
|
|
"""
|
|
to_header = str(msg[headers.TO]) if msg[headers.TO] else None
|
|
cc_header = str(msg[headers.CC]) if msg[headers.CC] else None
|
|
|
|
# nothing to do
|
|
if to_header and alias.email in to_header:
|
|
return
|
|
|
|
# nothing to do
|
|
if cc_header and alias.email in cc_header:
|
|
return
|
|
|
|
LOG.d(f"add {alias} to To: header {to_header}")
|
|
|
|
if to_header:
|
|
add_or_replace_header(msg, headers.TO, f"{to_header},{alias.email}")
|
|
else:
|
|
add_or_replace_header(msg, headers.TO, alias.email)
|
|
|
|
|
|
def replace_header_when_reply(msg: Message, alias: Alias, header: str):
|
|
"""
|
|
Replace CC or To Reply emails by original emails
|
|
"""
|
|
new_addrs: [str] = []
|
|
headers = msg.get_all(header, [])
|
|
# headers can be an array of Header, convert it to string here
|
|
headers = [str(h) for h in headers]
|
|
|
|
# headers can contain \r or \n
|
|
headers = [h.replace("\r", "") for h in headers]
|
|
headers = [h.replace("\n", "") for h in headers]
|
|
|
|
for _, reply_email in getaddresses(headers):
|
|
# no transformation when alias is already in the header
|
|
# can happen when user clicks "Reply All"
|
|
if reply_email == alias.email:
|
|
continue
|
|
|
|
contact = Contact.get_by(reply_email=reply_email)
|
|
if not contact:
|
|
LOG.w(
|
|
"email %s contained in %s header in reply phase must be reply emails. headers:%s",
|
|
reply_email,
|
|
header,
|
|
headers,
|
|
)
|
|
raise NonReverseAliasInReplyPhase(reply_email)
|
|
# still keep this email in header
|
|
# new_addrs.append(reply_email)
|
|
else:
|
|
new_addrs.append(sl_formataddr((contact.name, contact.website_email)))
|
|
|
|
if new_addrs:
|
|
new_header = ",".join(new_addrs)
|
|
LOG.d("Replace %s header, old: %s, new: %s", header, msg[header], new_header)
|
|
add_or_replace_header(msg, header, new_header)
|
|
else:
|
|
LOG.d("delete the %s header. Old value %s", header, msg[header])
|
|
delete_header(msg, header)
|
|
|
|
|
|
def prepare_pgp_message(
|
|
orig_msg: Message, pgp_fingerprint: str, public_key: str, can_sign: bool = False
|
|
) -> Message:
|
|
msg = MIMEMultipart("encrypted", protocol="application/pgp-encrypted")
|
|
|
|
# clone orig message to avoid modifying it
|
|
clone_msg = copy(orig_msg)
|
|
|
|
# copy all headers from original message except all standard MIME headers
|
|
for i in reversed(range(len(clone_msg._headers))):
|
|
header_name = clone_msg._headers[i][0].lower()
|
|
if header_name.lower() not in headers.MIME_HEADERS:
|
|
msg[header_name] = clone_msg._headers[i][1]
|
|
|
|
# Delete unnecessary headers in clone_msg except _MIME_HEADERS to save space
|
|
delete_all_headers_except(
|
|
clone_msg,
|
|
headers.MIME_HEADERS,
|
|
)
|
|
|
|
if clone_msg[headers.CONTENT_TYPE] is None:
|
|
LOG.d("Content-Type missing")
|
|
clone_msg[headers.CONTENT_TYPE] = "text/plain"
|
|
|
|
if clone_msg[headers.MIME_VERSION] is None:
|
|
LOG.d("Mime-Version missing")
|
|
clone_msg[headers.MIME_VERSION] = "1.0"
|
|
|
|
first = MIMEApplication(
|
|
_subtype="pgp-encrypted", _encoder=encoders.encode_7or8bit, _data=""
|
|
)
|
|
first.set_payload("Version: 1")
|
|
msg.attach(first)
|
|
|
|
if can_sign and PGP_SENDER_PRIVATE_KEY:
|
|
LOG.d("Sign msg")
|
|
clone_msg = sign_msg(clone_msg)
|
|
|
|
# use pgpy as fallback
|
|
second = MIMEApplication(
|
|
"octet-stream", _encoder=encoders.encode_7or8bit, name="encrypted.asc"
|
|
)
|
|
second.add_header("Content-Disposition", 'inline; filename="encrypted.asc"')
|
|
|
|
# encrypt
|
|
# use pgpy as fallback
|
|
msg_bytes = message_to_bytes(clone_msg)
|
|
try:
|
|
encrypted_data = pgp_utils.encrypt_file(BytesIO(msg_bytes), pgp_fingerprint)
|
|
second.set_payload(encrypted_data)
|
|
except PGPException:
|
|
LOG.w(
|
|
"Cannot encrypt using python-gnupg, check if public key is valid and try with pgpy"
|
|
)
|
|
# check if the public key is valid
|
|
load_public_key_and_check(public_key)
|
|
|
|
encrypted = pgp_utils.encrypt_file_with_pgpy(msg_bytes, public_key)
|
|
second.set_payload(str(encrypted))
|
|
LOG.i(
|
|
f"encryption works with pgpy and not with python-gnupg, public key {public_key}"
|
|
)
|
|
|
|
msg.attach(second)
|
|
|
|
return msg
|
|
|
|
|
|
def sign_msg(msg: Message) -> Message:
|
|
container = MIMEMultipart(
|
|
"signed", protocol="application/pgp-signature", micalg="pgp-sha256"
|
|
)
|
|
container.attach(msg)
|
|
|
|
signature = MIMEApplication(
|
|
_subtype="pgp-signature", name="signature.asc", _data="", _encoder=encode_noop
|
|
)
|
|
signature.add_header("Content-Disposition", 'attachment; filename="signature.asc"')
|
|
|
|
try:
|
|
signature.set_payload(sign_data(message_to_bytes(msg).replace(b"\n", b"\r\n")))
|
|
except Exception:
|
|
LOG.e("Cannot sign, try using pgpy")
|
|
signature.set_payload(
|
|
sign_data_with_pgpy(message_to_bytes(msg).replace(b"\n", b"\r\n"))
|
|
)
|
|
|
|
container.attach(signature)
|
|
|
|
return container
|
|
|
|
|
|
def handle_email_sent_to_ourself(alias, from_addr: str, msg: Message, user):
|
|
# store the refused email
|
|
random_name = str(uuid.uuid4())
|
|
full_report_path = f"refused-emails/cycle-{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
full_report_path, BytesIO(message_to_bytes(msg)), random_name
|
|
)
|
|
refused_email = RefusedEmail.create(
|
|
path=None, full_report_path=full_report_path, user_id=alias.user_id
|
|
)
|
|
Session.commit()
|
|
LOG.d("Create refused email %s", refused_email)
|
|
# link available for 6 days as it gets deleted in 7 days
|
|
refused_email_url = refused_email.get_url(expires_in=518400)
|
|
|
|
Notification.create(
|
|
user_id=user.id,
|
|
title=f"Email sent to {alias.email} from its own mailbox {from_addr}",
|
|
message=Notification.render(
|
|
"notification/cycle-email.html",
|
|
alias=alias,
|
|
from_addr=from_addr,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
commit=True,
|
|
)
|
|
|
|
send_email_at_most_times(
|
|
user,
|
|
ALERT_SEND_EMAIL_CYCLE,
|
|
from_addr,
|
|
f"Email sent to {alias.email} from its own mailbox {from_addr}",
|
|
render(
|
|
"transactional/cycle-email.txt.jinja2",
|
|
alias=alias,
|
|
from_addr=from_addr,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
render(
|
|
"transactional/cycle-email.html",
|
|
alias=alias,
|
|
from_addr=from_addr,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
)
|
|
|
|
|
|
def handle_forward(envelope, msg: Message, rcpt_to: str) -> List[Tuple[bool, str]]:
|
|
"""return an array of SMTP status (is_success, smtp_status)
|
|
is_success indicates whether an email has been delivered and
|
|
smtp_status is the SMTP Status ("250 Message accepted", "550 Non-existent email address", etc.)
|
|
"""
|
|
alias_address = rcpt_to # alias@SL
|
|
|
|
alias = Alias.get_by(email=alias_address)
|
|
if not alias:
|
|
LOG.d(
|
|
"alias %s not exist. Try to see if it can be created on the fly",
|
|
alias_address,
|
|
)
|
|
alias = try_auto_create(alias_address)
|
|
if not alias:
|
|
LOG.d("alias %s cannot be created on-the-fly, return 550", alias_address)
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return [(True, status.E207)]
|
|
else:
|
|
return [(False, status.E515)]
|
|
|
|
user = alias.user
|
|
|
|
if user.disabled:
|
|
LOG.w("User %s disabled, disable forwarding emails for %s", user, alias)
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return [(True, status.E207)]
|
|
else:
|
|
return [(False, status.E504)]
|
|
|
|
# check if email is sent from alias's owning mailbox(es)
|
|
mail_from = envelope.mail_from
|
|
for addr in alias.authorized_addresses():
|
|
# email sent from a mailbox to its alias
|
|
if addr == mail_from:
|
|
LOG.i("cycle email sent from %s to %s", addr, alias)
|
|
handle_email_sent_to_ourself(alias, addr, msg, user)
|
|
return [(True, status.E209)]
|
|
|
|
from_header = get_header_unicode(msg[headers.FROM])
|
|
LOG.d("Create or get contact for from_header:%s", from_header)
|
|
try:
|
|
contact = get_or_create_contact(from_header, envelope.mail_from, alias)
|
|
except ObjectDeletedError:
|
|
LOG.d("maybe alias was deleted in the meantime")
|
|
alias = Alias.get_by(email=alias_address)
|
|
if not alias:
|
|
LOG.i("Alias %s was deleted in the meantime", alias_address)
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return [(True, status.E207)]
|
|
else:
|
|
return [(False, status.E515)]
|
|
|
|
reply_to_contact = None
|
|
if msg[headers.REPLY_TO]:
|
|
reply_to = get_header_unicode(msg[headers.REPLY_TO])
|
|
LOG.d("Create or get contact for reply_to_header:%s", reply_to)
|
|
# ignore when reply-to = alias
|
|
if reply_to == alias.email:
|
|
LOG.i("Reply-to same as alias %s", alias)
|
|
else:
|
|
reply_to_contact = get_or_create_reply_to_contact(reply_to, alias, msg)
|
|
|
|
if not alias.enabled or contact.block_forward:
|
|
LOG.d("%s is disabled, do not forward", alias)
|
|
EmailLog.create(
|
|
contact_id=contact.id,
|
|
user_id=contact.user_id,
|
|
blocked=True,
|
|
alias_id=contact.alias_id,
|
|
commit=True,
|
|
)
|
|
|
|
res_status = status.E200
|
|
if user.block_behaviour == BlockBehaviourEnum.return_5xx:
|
|
res_status = status.E502
|
|
|
|
# do not return 5** to allow user to receive emails later when alias is enabled or contact is unblocked
|
|
return [(True, res_status)]
|
|
|
|
# Check if we need to reject or quarantine based on dmarc
|
|
msg, dmarc_delivery_status = apply_dmarc_policy_for_forward_phase(
|
|
alias, contact, envelope, msg
|
|
)
|
|
if dmarc_delivery_status is not None:
|
|
return [(False, dmarc_delivery_status)]
|
|
|
|
ret = []
|
|
mailboxes = alias.mailboxes
|
|
|
|
# no valid mailbox
|
|
if not mailboxes:
|
|
LOG.w("no valid mailboxes for %s", alias)
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return [(True, status.E207)]
|
|
else:
|
|
return [(False, status.E516)]
|
|
|
|
for mailbox in mailboxes:
|
|
if not mailbox.verified:
|
|
LOG.d("%s unverified, do not forward", mailbox)
|
|
ret.append((False, status.E517))
|
|
else:
|
|
# create a copy of message for each forward
|
|
ret.append(
|
|
forward_email_to_mailbox(
|
|
alias, copy(msg), contact, envelope, mailbox, user, reply_to_contact
|
|
)
|
|
)
|
|
|
|
return ret
|
|
|
|
|
|
def forward_email_to_mailbox(
|
|
alias,
|
|
msg: Message,
|
|
contact: Contact,
|
|
envelope,
|
|
mailbox,
|
|
user,
|
|
reply_to_contact: Optional[Contact],
|
|
) -> (bool, str):
|
|
LOG.d("Forward %s -> %s -> %s", contact, alias, mailbox)
|
|
|
|
if mailbox.disabled:
|
|
LOG.d("%s disabled, do not forward")
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return True, status.E207
|
|
else:
|
|
return False, status.E518
|
|
|
|
# sanity check: make sure mailbox is not actually an alias
|
|
if get_email_domain_part(alias.email) == get_email_domain_part(mailbox.email):
|
|
LOG.w(
|
|
"Mailbox has the same domain as alias. %s -> %s -> %s",
|
|
contact,
|
|
alias,
|
|
mailbox,
|
|
)
|
|
mailbox_url = f"{URL}/dashboard/mailbox/{mailbox.id}/"
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_MAILBOX_IS_ALIAS,
|
|
user.email,
|
|
f"Your mailbox {mailbox.email} and alias {alias.email} use the same domain",
|
|
render(
|
|
"transactional/mailbox-invalid.txt.jinja2",
|
|
mailbox=mailbox,
|
|
mailbox_url=mailbox_url,
|
|
alias=alias,
|
|
),
|
|
render(
|
|
"transactional/mailbox-invalid.html",
|
|
mailbox=mailbox,
|
|
mailbox_url=mailbox_url,
|
|
alias=alias,
|
|
),
|
|
max_nb_alert=1,
|
|
)
|
|
|
|
# retry later
|
|
# so when user fixes the mailbox, the email can be delivered
|
|
return False, status.E405
|
|
|
|
email_log = EmailLog.create(
|
|
contact_id=contact.id,
|
|
user_id=user.id,
|
|
mailbox_id=mailbox.id,
|
|
alias_id=contact.alias_id,
|
|
message_id=str(msg[headers.MESSAGE_ID]),
|
|
commit=True,
|
|
)
|
|
LOG.d("Create %s for %s, %s, %s", email_log, contact, user, mailbox)
|
|
|
|
if ENABLE_SPAM_ASSASSIN:
|
|
# Spam check
|
|
spam_status = ""
|
|
is_spam = False
|
|
|
|
if SPAMASSASSIN_HOST:
|
|
start = time.time()
|
|
spam_score, spam_report = get_spam_score(msg, email_log)
|
|
LOG.d(
|
|
"%s -> %s - spam score:%s in %s seconds. Spam report %s",
|
|
contact,
|
|
alias,
|
|
spam_score,
|
|
time.time() - start,
|
|
spam_report,
|
|
)
|
|
email_log.spam_score = spam_score
|
|
Session.commit()
|
|
|
|
if (user.max_spam_score and spam_score > user.max_spam_score) or (
|
|
not user.max_spam_score and spam_score > MAX_SPAM_SCORE
|
|
):
|
|
is_spam = True
|
|
# only set the spam report for spam
|
|
email_log.spam_report = spam_report
|
|
else:
|
|
is_spam, spam_status = get_spam_info(msg, max_score=user.max_spam_score)
|
|
|
|
if is_spam:
|
|
LOG.w(
|
|
"Email detected as spam. %s -> %s. Spam Score: %s, Spam Report: %s",
|
|
contact,
|
|
alias,
|
|
email_log.spam_score,
|
|
email_log.spam_report,
|
|
)
|
|
email_log.is_spam = True
|
|
email_log.spam_status = spam_status
|
|
Session.commit()
|
|
|
|
handle_spam(contact, alias, msg, user, mailbox, email_log)
|
|
return False, status.E519
|
|
|
|
if contact.invalid_email:
|
|
LOG.d("add noreply information %s %s", alias, mailbox)
|
|
msg = add_header(
|
|
msg,
|
|
f"""Email sent to {alias.email} from an invalid address and cannot be replied""",
|
|
f"""Email sent to {alias.email} from an invalid address and cannot be replied""",
|
|
)
|
|
|
|
delete_all_headers_except(
|
|
msg,
|
|
[
|
|
headers.FROM,
|
|
headers.TO,
|
|
headers.CC,
|
|
headers.SUBJECT,
|
|
headers.DATE,
|
|
# do not delete original message id
|
|
headers.MESSAGE_ID,
|
|
# References and In-Reply-To are used for keeping the email thread
|
|
headers.REFERENCES,
|
|
headers.IN_REPLY_TO,
|
|
]
|
|
+ headers.MIME_HEADERS,
|
|
)
|
|
|
|
# create PGP email if needed
|
|
if mailbox.pgp_enabled() and user.is_premium() and not alias.disable_pgp:
|
|
LOG.d("Encrypt message using mailbox %s", mailbox)
|
|
if mailbox.generic_subject:
|
|
LOG.d("Use a generic subject for %s", mailbox)
|
|
orig_subject = msg[headers.SUBJECT]
|
|
orig_subject = get_header_unicode(orig_subject)
|
|
add_or_replace_header(msg, "Subject", mailbox.generic_subject)
|
|
msg = add_header(
|
|
msg,
|
|
f"""Forwarded by SimpleLogin to {alias.email} with "{orig_subject}" as subject""",
|
|
f"""Forwarded by SimpleLogin to {alias.email} with <b>{orig_subject}</b> as subject""",
|
|
)
|
|
|
|
try:
|
|
msg = prepare_pgp_message(
|
|
msg, mailbox.pgp_finger_print, mailbox.pgp_public_key, can_sign=True
|
|
)
|
|
except PGPException:
|
|
LOG.w(
|
|
"Cannot encrypt message %s -> %s. %s %s", contact, alias, mailbox, user
|
|
)
|
|
msg = add_header(
|
|
msg,
|
|
f"""PGP encryption fails with {mailbox.email}'s PGP key""",
|
|
)
|
|
|
|
# add custom header
|
|
add_or_replace_header(msg, headers.SL_DIRECTION, "Forward")
|
|
|
|
msg[headers.SL_EMAIL_LOG_ID] = str(email_log.id)
|
|
if user.include_header_email_header:
|
|
msg[headers.SL_ENVELOPE_FROM] = envelope.mail_from
|
|
# when an alias isn't in the To: header, there's no way for users to know what alias has received the email
|
|
msg[headers.SL_ENVELOPE_TO] = alias.email
|
|
|
|
if not msg[headers.DATE]:
|
|
LOG.w("missing date header, create one")
|
|
msg[headers.DATE] = formatdate()
|
|
|
|
replace_sl_message_id_by_original_message_id(msg)
|
|
|
|
# change the from_header so the email comes from a reverse-alias
|
|
# replace the email part in from: header
|
|
old_from_header = msg[headers.FROM]
|
|
new_from_header = contact.new_addr()
|
|
add_or_replace_header(msg, "From", new_from_header)
|
|
LOG.d("From header, new:%s, old:%s", new_from_header, old_from_header)
|
|
|
|
if reply_to_contact:
|
|
reply_to_header = msg[headers.REPLY_TO]
|
|
new_reply_to_header = reply_to_contact.new_addr()
|
|
add_or_replace_header(msg, "Reply-To", new_reply_to_header)
|
|
LOG.d("Reply-To header, new:%s, old:%s", new_reply_to_header, reply_to_header)
|
|
|
|
# replace CC & To emails by reverse-alias for all emails that are not alias
|
|
try:
|
|
replace_header_when_forward(msg, alias, headers.CC)
|
|
replace_header_when_forward(msg, alias, headers.TO)
|
|
except CannotCreateContactForReverseAlias:
|
|
LOG.d("CannotCreateContactForReverseAlias error, delete %s", email_log)
|
|
EmailLog.delete(email_log.id)
|
|
Session.commit()
|
|
raise
|
|
|
|
# add alias to To: header if it isn't included in To and Cc header
|
|
add_alias_to_header_if_needed(msg, alias)
|
|
|
|
# add List-Unsubscribe header
|
|
msg = UnsubscribeGenerator().add_header_to_message(alias, contact, msg)
|
|
|
|
add_dkim_signature(msg, EMAIL_DOMAIN)
|
|
|
|
LOG.d(
|
|
"Forward mail from %s to %s, mail_options:%s, rcpt_options:%s ",
|
|
contact.website_email,
|
|
mailbox.email,
|
|
envelope.mail_options,
|
|
envelope.rcpt_options,
|
|
)
|
|
|
|
try:
|
|
sl_sendmail(
|
|
# use a different envelope sender for each forward (aka VERP)
|
|
generate_verp_email(VerpType.bounce_forward, email_log.id),
|
|
mailbox.email,
|
|
msg,
|
|
envelope.mail_options,
|
|
envelope.rcpt_options,
|
|
is_forward=True,
|
|
)
|
|
except (SMTPServerDisconnected, SMTPRecipientsRefused, TimeoutError):
|
|
LOG.w(
|
|
"Postfix error during forward phase %s -> %s -> %s",
|
|
contact,
|
|
alias,
|
|
mailbox,
|
|
exc_info=True,
|
|
)
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return True, status.E207
|
|
else:
|
|
EmailLog.delete(email_log.id, commit=True)
|
|
# so Postfix can retry
|
|
return False, status.E407
|
|
else:
|
|
Session.commit()
|
|
return True, status.E200
|
|
|
|
|
|
def replace_sl_message_id_by_original_message_id(msg):
|
|
# Replace SL Message-ID by original one in In-Reply-To header
|
|
if msg[headers.IN_REPLY_TO]:
|
|
matching: MessageIDMatching = MessageIDMatching.get_by(
|
|
sl_message_id=str(msg[headers.IN_REPLY_TO])
|
|
)
|
|
if matching:
|
|
LOG.d(
|
|
"replace SL message id by original one in in-reply-to header, %s -> %s",
|
|
msg[headers.IN_REPLY_TO],
|
|
matching.original_message_id,
|
|
)
|
|
del msg[headers.IN_REPLY_TO]
|
|
msg[headers.IN_REPLY_TO] = matching.original_message_id
|
|
|
|
# Replace SL Message-ID by original Message-ID in References header
|
|
if msg[headers.REFERENCES]:
|
|
message_ids = str(msg[headers.REFERENCES]).split()
|
|
new_message_ids = []
|
|
for message_id in message_ids:
|
|
matching = MessageIDMatching.get_by(sl_message_id=message_id)
|
|
if matching:
|
|
LOG.d(
|
|
"replace SL message id by original one in references header, %s -> %s",
|
|
message_id,
|
|
matching.original_message_id,
|
|
)
|
|
new_message_ids.append(matching.original_message_id)
|
|
else:
|
|
new_message_ids.append(message_id)
|
|
|
|
del msg[headers.REFERENCES]
|
|
msg[headers.REFERENCES] = " ".join(new_message_ids)
|
|
|
|
|
|
def handle_reply(envelope, msg: Message, rcpt_to: str) -> (bool, str):
|
|
"""
|
|
Return whether an email has been delivered and
|
|
the smtp status ("250 Message accepted", "550 Non-existent email address", etc)
|
|
"""
|
|
|
|
reply_email = rcpt_to
|
|
|
|
# reply_email must end with EMAIL_DOMAIN
|
|
if not reply_email.endswith(EMAIL_DOMAIN):
|
|
LOG.w(f"Reply email {reply_email} has wrong domain")
|
|
return False, status.E501
|
|
|
|
# handle case where reply email is generated with non-allowed char
|
|
reply_email = normalize_reply_email(reply_email)
|
|
|
|
contact = Contact.get_by(reply_email=reply_email)
|
|
if not contact:
|
|
LOG.w(f"No contact with {reply_email} as reverse alias")
|
|
return False, status.E502
|
|
|
|
alias = contact.alias
|
|
alias_address: str = contact.alias.email
|
|
alias_domain = alias_address[alias_address.find("@") + 1 :]
|
|
|
|
# Sanity check: verify alias domain is managed by SimpleLogin
|
|
# scenario: a user have removed a domain but due to a bug, the aliases are still there
|
|
if not is_valid_alias_address_domain(alias.email):
|
|
LOG.e("%s domain isn't known", alias)
|
|
return False, status.E503
|
|
|
|
user = alias.user
|
|
mail_from = envelope.mail_from
|
|
|
|
if user.disabled:
|
|
LOG.e(
|
|
"User %s disabled, disable sending emails from %s to %s",
|
|
user,
|
|
alias,
|
|
contact,
|
|
)
|
|
return False, status.E504
|
|
|
|
# Check if we need to reject or quarantine based on dmarc
|
|
dmarc_delivery_status = apply_dmarc_policy_for_reply_phase(
|
|
alias, contact, envelope, msg
|
|
)
|
|
if dmarc_delivery_status is not None:
|
|
return False, dmarc_delivery_status
|
|
|
|
# Anti-spoofing
|
|
mailbox = get_mailbox_from_mail_from(mail_from, alias)
|
|
if not mailbox:
|
|
if alias.disable_email_spoofing_check:
|
|
# ignore this error, use default alias mailbox
|
|
LOG.w(
|
|
"ignore unknown sender to reverse-alias %s: %s -> %s",
|
|
mail_from,
|
|
alias,
|
|
contact,
|
|
)
|
|
mailbox = alias.mailbox
|
|
else:
|
|
# only mailbox can send email to the reply-email
|
|
handle_unknown_mailbox(envelope, msg, reply_email, user, alias, contact)
|
|
# return 2** to avoid Postfix sending out bounces and avoid backscatter issue
|
|
return False, status.E214
|
|
|
|
if ENFORCE_SPF and mailbox.force_spf and not alias.disable_email_spoofing_check:
|
|
if not spf_pass(envelope, mailbox, user, alias, contact.website_email, msg):
|
|
# cannot use 4** here as sender will retry.
|
|
# cannot use 5** because that generates bounce report
|
|
return True, status.E201
|
|
|
|
email_log = EmailLog.create(
|
|
contact_id=contact.id,
|
|
alias_id=contact.alias_id,
|
|
is_reply=True,
|
|
user_id=contact.user_id,
|
|
mailbox_id=mailbox.id,
|
|
message_id=msg[headers.MESSAGE_ID],
|
|
commit=True,
|
|
)
|
|
LOG.d("Create %s for %s, %s, %s", email_log, contact, user, mailbox)
|
|
|
|
# Spam check
|
|
if ENABLE_SPAM_ASSASSIN:
|
|
spam_status = ""
|
|
is_spam = False
|
|
|
|
# do not use user.max_spam_score here
|
|
if SPAMASSASSIN_HOST:
|
|
start = time.time()
|
|
spam_score, spam_report = get_spam_score(msg, email_log)
|
|
LOG.d(
|
|
"%s -> %s - spam score %s in %s seconds. Spam report %s",
|
|
alias,
|
|
contact,
|
|
spam_score,
|
|
time.time() - start,
|
|
spam_report,
|
|
)
|
|
email_log.spam_score = spam_score
|
|
if spam_score > MAX_REPLY_PHASE_SPAM_SCORE:
|
|
is_spam = True
|
|
# only set the spam report for spam
|
|
email_log.spam_report = spam_report
|
|
else:
|
|
is_spam, spam_status = get_spam_info(
|
|
msg, max_score=MAX_REPLY_PHASE_SPAM_SCORE
|
|
)
|
|
|
|
if is_spam:
|
|
LOG.w(
|
|
"Email detected as spam. Reply phase. %s -> %s. Spam Score: %s, Spam Report: %s",
|
|
alias,
|
|
contact,
|
|
email_log.spam_score,
|
|
email_log.spam_report,
|
|
)
|
|
|
|
email_log.is_spam = True
|
|
email_log.spam_status = spam_status
|
|
Session.commit()
|
|
|
|
handle_spam(contact, alias, msg, user, mailbox, email_log, is_reply=True)
|
|
return False, status.E506
|
|
|
|
delete_all_headers_except(
|
|
msg,
|
|
[
|
|
headers.FROM,
|
|
headers.TO,
|
|
headers.CC,
|
|
headers.SUBJECT,
|
|
headers.DATE,
|
|
# do not delete original message id
|
|
headers.MESSAGE_ID,
|
|
# References and In-Reply-To are used for keeping the email thread
|
|
headers.REFERENCES,
|
|
headers.IN_REPLY_TO,
|
|
]
|
|
+ headers.MIME_HEADERS,
|
|
)
|
|
|
|
# replace the reverse-alias by the contact email in the email body
|
|
# as this is usually included when replying
|
|
if user.replace_reverse_alias:
|
|
LOG.d("Replace reverse-alias %s by contact email %s", reply_email, contact)
|
|
msg = replace(msg, reply_email, contact.website_email)
|
|
|
|
# create PGP email if needed
|
|
if contact.pgp_finger_print and user.is_premium():
|
|
LOG.d("Encrypt message for contact %s", contact)
|
|
try:
|
|
msg = prepare_pgp_message(
|
|
msg, contact.pgp_finger_print, contact.pgp_public_key
|
|
)
|
|
except PGPException:
|
|
LOG.e(
|
|
"Cannot encrypt message %s -> %s. %s %s", alias, contact, mailbox, user
|
|
)
|
|
# programming error, user shouldn't see a new email log
|
|
EmailLog.delete(email_log.id, commit=True)
|
|
# return 421 so the client can retry later
|
|
return False, status.E402
|
|
|
|
Session.commit()
|
|
|
|
# make the email comes from alias
|
|
from_header = alias.email
|
|
# add alias name from alias
|
|
if alias.name:
|
|
LOG.d("Put alias name %s in from header", alias.name)
|
|
from_header = sl_formataddr((alias.name, alias.email))
|
|
elif alias.custom_domain:
|
|
# add alias name from domain
|
|
if alias.custom_domain.name:
|
|
LOG.d(
|
|
"Put domain default alias name %s in from header",
|
|
alias.custom_domain.name,
|
|
)
|
|
from_header = sl_formataddr((alias.custom_domain.name, alias.email))
|
|
|
|
LOG.d("From header is %s", from_header)
|
|
add_or_replace_header(msg, headers.FROM, from_header)
|
|
|
|
try:
|
|
if str(msg[headers.TO]).lower() == "undisclosed-recipients:;":
|
|
# no need to replace TO header
|
|
LOG.d("email is sent in BCC mode")
|
|
del msg[headers.TO]
|
|
else:
|
|
replace_header_when_reply(msg, alias, headers.TO)
|
|
|
|
replace_header_when_reply(msg, alias, headers.CC)
|
|
except NonReverseAliasInReplyPhase as e:
|
|
LOG.w("non reverse-alias in reply %s %s %s", e, contact, alias)
|
|
|
|
# the email is ignored, delete the email log
|
|
EmailLog.delete(email_log.id, commit=True)
|
|
|
|
send_email(
|
|
mailbox.email,
|
|
f"Email sent to {contact.email} contains non reverse-alias addresses",
|
|
render(
|
|
"transactional/non-reverse-alias-reply-phase.txt.jinja2",
|
|
destination=contact.email,
|
|
alias=alias.email,
|
|
subject=msg[headers.SUBJECT],
|
|
),
|
|
)
|
|
# user is informed and will retry
|
|
return True, status.E200
|
|
|
|
replace_original_message_id(alias, email_log, msg)
|
|
|
|
if not msg[headers.DATE]:
|
|
date_header = formatdate()
|
|
LOG.w("missing date header, add one")
|
|
msg[headers.DATE] = date_header
|
|
|
|
msg[headers.SL_DIRECTION] = "Reply"
|
|
msg[headers.SL_EMAIL_LOG_ID] = str(email_log.id)
|
|
|
|
LOG.d(
|
|
"send email from %s to %s, mail_options:%s,rcpt_options:%s",
|
|
alias.email,
|
|
contact.website_email,
|
|
envelope.mail_options,
|
|
envelope.rcpt_options,
|
|
)
|
|
|
|
if should_add_dkim_signature(alias_domain):
|
|
add_dkim_signature(msg, alias_domain)
|
|
|
|
try:
|
|
sl_sendmail(
|
|
generate_verp_email(VerpType.bounce_reply, email_log.id, alias_domain),
|
|
contact.website_email,
|
|
msg,
|
|
envelope.mail_options,
|
|
envelope.rcpt_options,
|
|
is_forward=False,
|
|
)
|
|
except Exception:
|
|
LOG.w("Cannot send email from %s to %s", alias, contact)
|
|
EmailLog.delete(email_log.id, commit=True)
|
|
send_email(
|
|
mailbox.email,
|
|
f"Email cannot be sent to {contact.email} from {alias.email}",
|
|
render(
|
|
"transactional/reply-error.txt.jinja2",
|
|
user=user,
|
|
alias=alias,
|
|
contact=contact,
|
|
contact_domain=get_email_domain_part(contact.email),
|
|
),
|
|
render(
|
|
"transactional/reply-error.html",
|
|
user=user,
|
|
alias=alias,
|
|
contact=contact,
|
|
contact_domain=get_email_domain_part(contact.email),
|
|
),
|
|
)
|
|
|
|
# return 250 even if error as user is already informed of the incident and can retry sending the email
|
|
return True, status.E200
|
|
|
|
|
|
def replace_original_message_id(alias: Alias, email_log: EmailLog, msg: Message):
|
|
"""
|
|
Replace original Message-ID by SL-Message-ID during the reply phase
|
|
for "message-id" and "References" headers
|
|
"""
|
|
original_message_id = msg[headers.MESSAGE_ID]
|
|
if original_message_id:
|
|
matching = MessageIDMatching.get_by(original_message_id=original_message_id)
|
|
# can happen when a user replies to multiple recipient from their alias
|
|
# a SL Message_id will be created for the first recipient
|
|
# it should be reused for other recipients
|
|
if matching:
|
|
sl_message_id = matching.sl_message_id
|
|
LOG.d("reuse the sl_message_id %s", sl_message_id)
|
|
else:
|
|
sl_message_id = make_msgid(
|
|
str(email_log.id), get_email_domain_part(alias.email)
|
|
)
|
|
LOG.d("create a new sl_message_id %s", sl_message_id)
|
|
try:
|
|
MessageIDMatching.create(
|
|
sl_message_id=sl_message_id,
|
|
original_message_id=original_message_id,
|
|
email_log_id=email_log.id,
|
|
commit=True,
|
|
)
|
|
except IntegrityError:
|
|
LOG.w(
|
|
"another matching with original_message_id %s was created in the mean time",
|
|
original_message_id,
|
|
)
|
|
Session.rollback()
|
|
matching = MessageIDMatching.get_by(
|
|
original_message_id=original_message_id
|
|
)
|
|
sl_message_id = matching.sl_message_id
|
|
else:
|
|
sl_message_id = make_msgid(
|
|
str(email_log.id), get_email_domain_part(alias.email)
|
|
)
|
|
LOG.d("no original_message_id, create a new sl_message_id %s", sl_message_id)
|
|
|
|
del msg[headers.MESSAGE_ID]
|
|
msg[headers.MESSAGE_ID] = sl_message_id
|
|
|
|
email_log.sl_message_id = sl_message_id
|
|
Session.commit()
|
|
|
|
# Replace all original headers in References header by SL Message ID header if needed
|
|
if msg[headers.REFERENCES]:
|
|
message_ids = str(msg[headers.REFERENCES]).split()
|
|
new_message_ids = []
|
|
for message_id in message_ids:
|
|
matching = MessageIDMatching.get_by(original_message_id=message_id)
|
|
if matching:
|
|
LOG.d(
|
|
"replace original message id by SL one, %s -> %s",
|
|
message_id,
|
|
matching.sl_message_id,
|
|
)
|
|
new_message_ids.append(matching.sl_message_id)
|
|
else:
|
|
new_message_ids.append(message_id)
|
|
|
|
del msg[headers.REFERENCES]
|
|
msg[headers.REFERENCES] = " ".join(new_message_ids)
|
|
|
|
|
|
def get_mailbox_from_mail_from(mail_from: str, alias) -> Optional[Mailbox]:
|
|
"""return the corresponding mailbox given the mail_from and alias
|
|
Usually the mail_from=mailbox.email but it can also be one of the authorized address
|
|
"""
|
|
for mailbox in alias.mailboxes:
|
|
if mailbox.email == mail_from:
|
|
return mailbox
|
|
|
|
for authorized_address in mailbox.authorized_addresses:
|
|
if authorized_address.email == mail_from:
|
|
LOG.d(
|
|
"Found an authorized address for %s %s %s",
|
|
alias,
|
|
mailbox,
|
|
authorized_address,
|
|
)
|
|
return mailbox
|
|
|
|
return None
|
|
|
|
|
|
def handle_unknown_mailbox(
|
|
envelope, msg, reply_email: str, user: User, alias: Alias, contact: Contact
|
|
):
|
|
LOG.w(
|
|
"Reply email can only be used by mailbox. "
|
|
"Actual mail_from: %s. msg from header: %s, reverse-alias %s, %s %s %s",
|
|
envelope.mail_from,
|
|
msg[headers.FROM],
|
|
reply_email,
|
|
alias,
|
|
user,
|
|
contact,
|
|
)
|
|
|
|
authorize_address_link = (
|
|
f"{URL}/dashboard/mailbox/{alias.mailbox_id}/#authorized-address"
|
|
)
|
|
mailbox_emails = [mailbox.email for mailbox in alias.mailboxes]
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_REVERSE_ALIAS_UNKNOWN_MAILBOX,
|
|
user.email,
|
|
f"Attempt to use your alias {alias.email} from {envelope.mail_from}",
|
|
render(
|
|
"transactional/reply-must-use-personal-email.txt",
|
|
alias=alias,
|
|
sender=envelope.mail_from,
|
|
authorize_address_link=authorize_address_link,
|
|
mailbox_emails=mailbox_emails,
|
|
),
|
|
render(
|
|
"transactional/reply-must-use-personal-email.html",
|
|
alias=alias,
|
|
sender=envelope.mail_from,
|
|
authorize_address_link=authorize_address_link,
|
|
mailbox_emails=mailbox_emails,
|
|
),
|
|
)
|
|
|
|
|
|
def handle_bounce_forward_phase(msg: Message, email_log: EmailLog):
|
|
"""
|
|
Handle forward phase bounce
|
|
Happens when an email cannot be sent to a mailbox
|
|
"""
|
|
contact = email_log.contact
|
|
alias = contact.alias
|
|
user = alias.user
|
|
mailbox = email_log.mailbox
|
|
|
|
# email_log.mailbox should be set during the forward phase
|
|
if not mailbox:
|
|
LOG.e("Use %s default mailbox %s", alias, alias.mailbox)
|
|
mailbox = alias.mailbox
|
|
|
|
bounce_info = get_mailbox_bounce_info(msg)
|
|
if bounce_info:
|
|
Bounce.create(
|
|
email=mailbox.email, info=bounce_info.as_bytes().decode(), commit=True
|
|
)
|
|
else:
|
|
LOG.w("cannot get bounce info, debug at %s", save_email_for_debugging(msg))
|
|
Bounce.create(email=mailbox.email, commit=True)
|
|
|
|
LOG.d(
|
|
"Handle forward bounce %s -> %s -> %s. %s", contact, alias, mailbox, email_log
|
|
)
|
|
|
|
# Store the bounced email, generate a name for the email
|
|
random_name = str(uuid.uuid4())
|
|
|
|
full_report_path = f"refused-emails/full-{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
full_report_path, BytesIO(message_to_bytes(msg)), f"full-{random_name}"
|
|
)
|
|
|
|
file_path = None
|
|
|
|
orig_msg = get_orig_message_from_bounce(msg)
|
|
if not orig_msg:
|
|
# Some MTA does not return the original message in bounce message
|
|
# nothing we can do here
|
|
LOG.w(
|
|
"Cannot parse original message from bounce message %s %s %s %s",
|
|
alias,
|
|
user,
|
|
contact,
|
|
full_report_path,
|
|
)
|
|
else:
|
|
file_path = f"refused-emails/{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
file_path, BytesIO(message_to_bytes(orig_msg)), random_name
|
|
)
|
|
|
|
refused_email = RefusedEmail.create(
|
|
path=file_path, full_report_path=full_report_path, user_id=user.id
|
|
)
|
|
Session.flush()
|
|
LOG.d("Create refused email %s", refused_email)
|
|
|
|
email_log.bounced = True
|
|
email_log.refused_email_id = refused_email.id
|
|
email_log.bounced_mailbox_id = mailbox.id
|
|
Session.commit()
|
|
|
|
refused_email_url = f"{URL}/dashboard/refused_email?highlight_id={email_log.id}"
|
|
|
|
alias_will_be_disabled, reason = should_disable(alias)
|
|
if alias_will_be_disabled:
|
|
LOG.w(
|
|
f"Disable alias {alias} because {reason}. {alias.mailboxes} {alias.user}. Last contact {contact}"
|
|
)
|
|
alias.enabled = False
|
|
|
|
Notification.create(
|
|
user_id=user.id,
|
|
title=f"{alias.email} has been disabled due to multiple bounces",
|
|
message=Notification.render(
|
|
"notification/alias-disable.html", alias=alias, mailbox=mailbox
|
|
),
|
|
)
|
|
|
|
Session.commit()
|
|
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_BOUNCE_EMAIL,
|
|
user.email,
|
|
f"Alias {alias.email} has been disabled due to multiple bounces",
|
|
render(
|
|
"transactional/bounce/automatic-disable-alias.txt",
|
|
alias=alias,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox.email,
|
|
),
|
|
render(
|
|
"transactional/bounce/automatic-disable-alias.html",
|
|
alias=alias,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox.email,
|
|
),
|
|
max_nb_alert=10,
|
|
ignore_smtp_error=True,
|
|
)
|
|
else:
|
|
LOG.d(
|
|
"Inform user %s about a bounce from contact %s to alias %s",
|
|
user,
|
|
contact,
|
|
alias,
|
|
)
|
|
disable_alias_link = f"{URL}/dashboard/unsubscribe/{alias.id}"
|
|
block_sender_link = f"{URL}/dashboard/alias_contact_manager/{alias.id}?highlight_contact_id={contact.id}"
|
|
|
|
Notification.create(
|
|
user_id=user.id,
|
|
title=f"Email from {contact.website_email} to {alias.email} cannot be delivered to {mailbox.email}",
|
|
message=Notification.render(
|
|
"notification/bounce-forward-phase.html",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email.get_url(),
|
|
mailbox_email=mailbox.email,
|
|
block_sender_link=block_sender_link,
|
|
),
|
|
commit=True,
|
|
)
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_BOUNCE_EMAIL,
|
|
user.email,
|
|
f"An email sent to {alias.email} cannot be delivered to your mailbox",
|
|
render(
|
|
"transactional/bounce/bounced-email.txt.jinja2",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
block_sender_link=block_sender_link,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox.email,
|
|
),
|
|
render(
|
|
"transactional/bounce/bounced-email.html",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox.email,
|
|
),
|
|
max_nb_alert=10,
|
|
# smtp error can happen if user mailbox is unreachable, that might explain the bounce
|
|
ignore_smtp_error=True,
|
|
)
|
|
|
|
|
|
def handle_bounce_reply_phase(envelope, msg: Message, email_log: EmailLog):
|
|
"""
|
|
Handle reply phase bounce
|
|
Happens when an email cannot be sent from an alias to a contact
|
|
"""
|
|
contact: Contact = email_log.contact
|
|
alias = contact.alias
|
|
user = alias.user
|
|
mailbox = email_log.mailbox or alias.mailbox
|
|
|
|
LOG.d("Handle reply bounce %s -> %s -> %s.%s", mailbox, alias, contact, email_log)
|
|
|
|
bounce_info = get_mailbox_bounce_info(msg)
|
|
if bounce_info:
|
|
Bounce.create(
|
|
email=sanitize_email(contact.website_email, not_lower=True),
|
|
info=bounce_info.as_bytes().decode(),
|
|
commit=True,
|
|
)
|
|
else:
|
|
LOG.w("cannot get bounce info, debug at %s", save_email_for_debugging(msg))
|
|
Bounce.create(
|
|
email=sanitize_email(contact.website_email, not_lower=True), commit=True
|
|
)
|
|
|
|
# Store the bounced email
|
|
# generate a name for the email
|
|
random_name = str(uuid.uuid4())
|
|
|
|
full_report_path = f"refused-emails/full-{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
full_report_path, BytesIO(message_to_bytes(msg)), random_name
|
|
)
|
|
|
|
orig_msg = get_orig_message_from_bounce(msg)
|
|
file_path = None
|
|
if orig_msg:
|
|
file_path = f"refused-emails/{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
file_path, BytesIO(message_to_bytes(orig_msg)), random_name
|
|
)
|
|
|
|
refused_email = RefusedEmail.create(
|
|
path=file_path, full_report_path=full_report_path, user_id=user.id, commit=True
|
|
)
|
|
LOG.d("Create refused email %s", refused_email)
|
|
|
|
email_log.bounced = True
|
|
email_log.refused_email_id = refused_email.id
|
|
|
|
email_log.bounced_mailbox_id = mailbox.id
|
|
|
|
Session.commit()
|
|
|
|
refused_email_url = f"{URL}/dashboard/refused_email?highlight_id={email_log.id}"
|
|
|
|
LOG.d(
|
|
"Inform user %s about bounced email sent by %s to %s",
|
|
user,
|
|
alias,
|
|
contact,
|
|
)
|
|
Notification.create(
|
|
user_id=user.id,
|
|
title=f"Email cannot be sent to { contact.email } from your alias { alias.email }",
|
|
message=Notification.render(
|
|
"notification/bounce-reply-phase.html",
|
|
alias=alias,
|
|
contact=contact,
|
|
refused_email_url=refused_email.get_url(),
|
|
),
|
|
commit=True,
|
|
)
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_BOUNCE_EMAIL_REPLY_PHASE,
|
|
mailbox.email,
|
|
f"Email cannot be sent to { contact.email } from your alias { alias.email }",
|
|
render(
|
|
"transactional/bounce/bounce-email-reply-phase.txt",
|
|
alias=alias,
|
|
contact=contact,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
render(
|
|
"transactional/bounce/bounce-email-reply-phase.html",
|
|
alias=alias,
|
|
contact=contact,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
)
|
|
|
|
|
|
def handle_spam(
|
|
contact: Contact,
|
|
alias: Alias,
|
|
msg: Message,
|
|
user: User,
|
|
mailbox: Mailbox,
|
|
email_log: EmailLog,
|
|
is_reply=False, # whether the email is in forward or reply phase
|
|
):
|
|
# Store the report & original email
|
|
orig_msg = get_orig_message_from_spamassassin_report(msg)
|
|
# generate a name for the email
|
|
random_name = str(uuid.uuid4())
|
|
|
|
full_report_path = f"spams/full-{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
full_report_path, BytesIO(message_to_bytes(msg)), random_name
|
|
)
|
|
|
|
file_path = None
|
|
if orig_msg:
|
|
file_path = f"spams/{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
file_path, BytesIO(message_to_bytes(orig_msg)), random_name
|
|
)
|
|
|
|
refused_email = RefusedEmail.create(
|
|
path=file_path, full_report_path=full_report_path, user_id=user.id
|
|
)
|
|
Session.flush()
|
|
|
|
email_log.refused_email_id = refused_email.id
|
|
Session.commit()
|
|
|
|
LOG.d("Create spam email %s", refused_email)
|
|
|
|
refused_email_url = f"{URL}/dashboard/refused_email?highlight_id={email_log.id}"
|
|
disable_alias_link = f"{URL}/dashboard/unsubscribe/{alias.id}"
|
|
|
|
if is_reply:
|
|
LOG.d(
|
|
"Inform %s (%s) about spam email sent from alias %s to %s. %s",
|
|
mailbox,
|
|
user,
|
|
alias,
|
|
contact,
|
|
refused_email,
|
|
)
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_SPAM_EMAIL,
|
|
mailbox.email,
|
|
f"Email from {alias.email} to {contact.website_email} is detected as spam",
|
|
render(
|
|
"transactional/spam-email-reply-phase.txt",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
render(
|
|
"transactional/spam-email-reply-phase.html",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
)
|
|
else:
|
|
# inform user
|
|
LOG.d(
|
|
"Inform %s (%s) about spam email sent by %s to alias %s",
|
|
mailbox,
|
|
user,
|
|
contact,
|
|
alias,
|
|
)
|
|
send_email_with_rate_control(
|
|
user,
|
|
ALERT_SPAM_EMAIL,
|
|
mailbox.email,
|
|
f"Email from {contact.website_email} to {alias.email} is detected as spam",
|
|
render(
|
|
"transactional/spam-email.txt",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
render(
|
|
"transactional/spam-email.html",
|
|
alias=alias,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
)
|
|
|
|
|
|
def is_automatic_out_of_office(msg: Message) -> bool:
|
|
"""
|
|
Return whether an email is out-of-office
|
|
For info, out-of-office is sent to the envelope mail_from and not the From: header
|
|
More info on https://datatracker.ietf.org/doc/html/rfc3834#section-4 and https://support.google.com/mail/thread/21246740/my-auto-reply-filter-isn-t-replying-to-original-sender-address?hl=en&msgid=21261237
|
|
"""
|
|
if msg[headers.AUTO_SUBMITTED] is None:
|
|
return False
|
|
|
|
if msg[headers.AUTO_SUBMITTED].lower() in ("auto-replied", "auto-generated"):
|
|
LOG.d(
|
|
"out-of-office email %s:%s",
|
|
headers.AUTO_SUBMITTED,
|
|
msg[headers.AUTO_SUBMITTED],
|
|
)
|
|
return True
|
|
|
|
return False
|
|
|
|
|
|
def is_bounce(envelope: Envelope, msg: Message):
|
|
"""Detect whether an email is a Delivery Status Notification"""
|
|
return (
|
|
envelope.mail_from == "<>"
|
|
and msg.get_content_type().lower() == "multipart/report"
|
|
)
|
|
|
|
|
|
def handle_transactional_bounce(
|
|
envelope: Envelope, msg, rcpt_to, transactional_id=None
|
|
):
|
|
LOG.d("handle transactional bounce sent to %s", rcpt_to)
|
|
|
|
# parse the TransactionalEmail
|
|
transactional_id = transactional_id or parse_id_from_bounce(rcpt_to)
|
|
transactional = TransactionalEmail.get(transactional_id)
|
|
|
|
# a transaction might have been deleted in delete_logs()
|
|
if transactional:
|
|
LOG.i("Create bounce for %s", transactional.email)
|
|
bounce_info = get_mailbox_bounce_info(msg)
|
|
if bounce_info:
|
|
Bounce.create(
|
|
email=transactional.email,
|
|
info=bounce_info.as_bytes().decode(),
|
|
commit=True,
|
|
)
|
|
else:
|
|
LOG.w("cannot get bounce info, debug at %s", save_email_for_debugging(msg))
|
|
Bounce.create(email=transactional.email, commit=True)
|
|
|
|
|
|
def handle_bounce(envelope, email_log: EmailLog, msg: Message) -> str:
|
|
"""
|
|
Return SMTP status, e.g. "500 Error"
|
|
"""
|
|
|
|
if not email_log:
|
|
LOG.w("No such email log")
|
|
return status.E512
|
|
|
|
contact: Contact = email_log.contact
|
|
alias = contact.alias
|
|
LOG.d(
|
|
"handle bounce for %s, phase=%s, contact=%s, alias=%s",
|
|
email_log,
|
|
email_log.get_phase(),
|
|
contact,
|
|
alias,
|
|
)
|
|
|
|
if email_log.is_reply:
|
|
content_type = msg.get_content_type().lower()
|
|
|
|
if content_type != "multipart/report" or envelope.mail_from != "<>":
|
|
# forward the email again to the alias
|
|
LOG.i(
|
|
"Handle auto reply %s %s",
|
|
content_type,
|
|
envelope.mail_from,
|
|
)
|
|
|
|
contact: Contact = email_log.contact
|
|
alias = contact.alias
|
|
|
|
email_log.auto_replied = True
|
|
Session.commit()
|
|
|
|
# replace the BOUNCE_EMAIL by alias in To field
|
|
add_or_replace_header(msg, "To", alias.email)
|
|
envelope.rcpt_tos = [alias.email]
|
|
|
|
# same as handle()
|
|
# result of all deliveries
|
|
# each element is a couple of whether the delivery is successful and the smtp status
|
|
res: [(bool, str)] = []
|
|
|
|
for is_delivered, smtp_status in handle_forward(envelope, msg, alias.email):
|
|
res.append((is_delivered, smtp_status))
|
|
|
|
for (is_success, smtp_status) in res:
|
|
# Consider all deliveries successful if 1 delivery is successful
|
|
if is_success:
|
|
return smtp_status
|
|
|
|
# Failed delivery for all, return the first failure
|
|
return res[0][1]
|
|
|
|
handle_bounce_reply_phase(envelope, msg, email_log)
|
|
return status.E212
|
|
else: # forward phase
|
|
handle_bounce_forward_phase(msg, email_log)
|
|
return status.E211
|
|
|
|
|
|
def should_ignore(mail_from: str, rcpt_tos: List[str]) -> bool:
|
|
if len(rcpt_tos) != 1:
|
|
return False
|
|
|
|
rcpt_to = rcpt_tos[0]
|
|
if IgnoredEmail.get_by(mail_from=mail_from, rcpt_to=rcpt_to):
|
|
return True
|
|
|
|
return False
|
|
|
|
|
|
def send_no_reply_response(mail_from: str, msg: Message):
|
|
mailbox = Mailbox.get_by(email=mail_from)
|
|
if not mailbox:
|
|
LOG.d("Unknown sender. Skipping reply from {}".format(NOREPLY))
|
|
return
|
|
send_email_at_most_times(
|
|
mailbox.user,
|
|
ALERT_TO_NOREPLY,
|
|
mailbox.user.email,
|
|
"Auto: {}".format(msg[headers.SUBJECT] or "No subject"),
|
|
render("transactional/noreply.text.jinja2"),
|
|
)
|
|
|
|
|
|
def handle(envelope: Envelope, msg: Message) -> str:
|
|
"""Return SMTP status"""
|
|
|
|
# sanitize mail_from, rcpt_tos
|
|
mail_from = sanitize_email(envelope.mail_from)
|
|
rcpt_tos = [sanitize_email(rcpt_to) for rcpt_to in envelope.rcpt_tos]
|
|
envelope.mail_from = mail_from
|
|
envelope.rcpt_tos = rcpt_tos
|
|
|
|
# some emails don't have this header, set the default value (7bit) in this case
|
|
if headers.CONTENT_TRANSFER_ENCODING not in msg:
|
|
LOG.i("Set CONTENT_TRANSFER_ENCODING")
|
|
msg[headers.CONTENT_TRANSFER_ENCODING] = "7bit"
|
|
|
|
postfix_queue_id = get_queue_id(msg)
|
|
if postfix_queue_id:
|
|
set_message_id(postfix_queue_id)
|
|
else:
|
|
LOG.d(
|
|
"Cannot parse Postfix queue ID from %s %s",
|
|
msg.get_all(headers.RECEIVED),
|
|
msg[headers.RECEIVED],
|
|
)
|
|
|
|
if should_ignore(mail_from, rcpt_tos):
|
|
LOG.w("Ignore email mail_from=%s rcpt_to=%s", mail_from, rcpt_tos)
|
|
return status.E204
|
|
|
|
# sanitize email headers
|
|
sanitize_header(msg, "from")
|
|
sanitize_header(msg, "to")
|
|
sanitize_header(msg, "cc")
|
|
sanitize_header(msg, "reply-to")
|
|
|
|
LOG.d(
|
|
"==>> Handle mail_from:%s, rcpt_tos:%s, header_from:%s, header_to:%s, "
|
|
"cc:%s, reply-to:%s, message_id:%s, client_ip:%s, headers:%s, mail_options:%s, rcpt_options:%s",
|
|
mail_from,
|
|
rcpt_tos,
|
|
msg[headers.FROM],
|
|
msg[headers.TO],
|
|
msg[headers.CC],
|
|
msg[headers.REPLY_TO],
|
|
msg[headers.MESSAGE_ID],
|
|
msg[headers.SL_CLIENT_IP],
|
|
msg._headers,
|
|
envelope.mail_options,
|
|
envelope.rcpt_options,
|
|
)
|
|
|
|
# region mail_from or from_header is a reverse alias which should never happen
|
|
email_sent_from_reverse_alias = False
|
|
contact = Contact.get_by(reply_email=mail_from)
|
|
if contact:
|
|
email_sent_from_reverse_alias = True
|
|
|
|
from_header = get_header_unicode(msg[headers.FROM])
|
|
if from_header:
|
|
try:
|
|
_, from_header_address = parse_full_address(from_header)
|
|
except ValueError:
|
|
LOG.w("cannot parse the From header %s", from_header)
|
|
else:
|
|
contact = Contact.get_by(reply_email=from_header_address)
|
|
if contact:
|
|
email_sent_from_reverse_alias = True
|
|
|
|
if email_sent_from_reverse_alias:
|
|
LOG.w(f"email sent from reverse alias {contact} {contact.alias} {contact.user}")
|
|
user = contact.user
|
|
send_email_at_most_times(
|
|
user,
|
|
ALERT_FROM_ADDRESS_IS_REVERSE_ALIAS,
|
|
user.email,
|
|
"SimpleLogin shouldn't be used with another email forwarding system",
|
|
render(
|
|
"transactional/email-sent-from-reverse-alias.txt.jinja2",
|
|
),
|
|
)
|
|
|
|
# endregion
|
|
|
|
# unsubscribe request
|
|
if UNSUBSCRIBER and (rcpt_tos == [UNSUBSCRIBER] or rcpt_tos == [OLD_UNSUBSCRIBER]):
|
|
LOG.d("Handle unsubscribe request from %s", mail_from)
|
|
return UnsubscribeHandler().handle_unsubscribe_from_message(envelope, msg)
|
|
|
|
# region mail sent to VERP
|
|
verp_info = get_verp_info_from_email(rcpt_tos[0])
|
|
|
|
# sent to transactional VERP. Either bounce emails or out-of-office
|
|
if (
|
|
len(rcpt_tos) == 1
|
|
and rcpt_tos[0].startswith(TRANSACTIONAL_BOUNCE_PREFIX)
|
|
and rcpt_tos[0].endswith(TRANSACTIONAL_BOUNCE_SUFFIX)
|
|
) or (verp_info and verp_info[0] == VerpType.transactional):
|
|
if is_bounce(envelope, msg):
|
|
handle_transactional_bounce(
|
|
envelope, msg, rcpt_tos[0], verp_info and verp_info[1]
|
|
)
|
|
return status.E205
|
|
elif is_automatic_out_of_office(msg):
|
|
LOG.d(
|
|
"Ignore out-of-office for transactional emails. Headers: %s", msg.items
|
|
)
|
|
return status.E206
|
|
else:
|
|
raise VERPTransactional
|
|
|
|
# sent to forward VERP, can be either bounce or out-of-office
|
|
if (
|
|
len(rcpt_tos) == 1
|
|
and rcpt_tos[0].startswith(BOUNCE_PREFIX)
|
|
and rcpt_tos[0].endswith(BOUNCE_SUFFIX)
|
|
) or (verp_info and verp_info[0] == VerpType.bounce_forward):
|
|
email_log_id = (verp_info and verp_info[1]) or parse_id_from_bounce(rcpt_tos[0])
|
|
email_log = EmailLog.get(email_log_id)
|
|
|
|
if not email_log:
|
|
LOG.w("No such email log")
|
|
return status.E512
|
|
|
|
if is_bounce(envelope, msg):
|
|
return handle_bounce(envelope, email_log, msg)
|
|
elif is_automatic_out_of_office(msg):
|
|
handle_out_of_office_forward_phase(email_log, envelope, msg, rcpt_tos)
|
|
else:
|
|
raise VERPForward
|
|
|
|
# sent to reply VERP, can be either bounce or out-of-office
|
|
if (
|
|
len(rcpt_tos) == 1
|
|
and rcpt_tos[0].startswith(f"{BOUNCE_PREFIX_FOR_REPLY_PHASE}+")
|
|
or (verp_info and verp_info[0] == VerpType.bounce_reply)
|
|
):
|
|
email_log_id = (verp_info and verp_info[1]) or parse_id_from_bounce(rcpt_tos[0])
|
|
email_log = EmailLog.get(email_log_id)
|
|
|
|
if not email_log:
|
|
LOG.w("No such email log")
|
|
return status.E512
|
|
|
|
# bounce by contact
|
|
if is_bounce(envelope, msg):
|
|
return handle_bounce(envelope, email_log, msg)
|
|
elif is_automatic_out_of_office(msg):
|
|
handle_out_of_office_reply_phase(email_log, envelope, msg, rcpt_tos)
|
|
else:
|
|
raise VERPReply(
|
|
f"cannot handle email sent to reply VERP, "
|
|
f"{email_log.alias} -> {email_log.contact} ({email_log}, {email_log.user}"
|
|
)
|
|
|
|
# iCloud returns the bounce with mail_from=bounce+{email_log_id}+@simplelogin.co, rcpt_to=alias
|
|
verp_info = get_verp_info_from_email(mail_from[0])
|
|
if (
|
|
len(rcpt_tos) == 1
|
|
and mail_from.startswith(BOUNCE_PREFIX)
|
|
and mail_from.endswith(BOUNCE_SUFFIX)
|
|
) or (verp_info and verp_info[0] == VerpType.bounce_forward):
|
|
email_log_id = (verp_info and verp_info[1]) or parse_id_from_bounce(mail_from)
|
|
email_log = EmailLog.get(email_log_id)
|
|
alias = Alias.get_by(email=rcpt_tos[0])
|
|
LOG.w(
|
|
"iCloud bounces %s %s, saved to%s",
|
|
email_log,
|
|
alias,
|
|
save_email_for_debugging(msg, file_name_prefix="icloud_bounce_"),
|
|
)
|
|
return handle_bounce(envelope, email_log, msg)
|
|
|
|
# endregion
|
|
|
|
# region hotmail, yahoo complaints
|
|
if (
|
|
len(rcpt_tos) == 1
|
|
and mail_from == "staff@hotmail.com"
|
|
and rcpt_tos[0] == POSTMASTER
|
|
):
|
|
LOG.w("Handle hotmail complaint")
|
|
|
|
# if the complaint cannot be handled, forward it normally
|
|
if handle_hotmail_complaint(msg):
|
|
return status.E208
|
|
|
|
if (
|
|
len(rcpt_tos) == 1
|
|
and mail_from == "feedback@arf.mail.yahoo.com"
|
|
and rcpt_tos[0] == POSTMASTER
|
|
):
|
|
LOG.w("Handle yahoo complaint")
|
|
|
|
# if the complaint cannot be handled, forward it normally
|
|
if handle_yahoo_complaint(msg):
|
|
return status.E210
|
|
|
|
# endregion
|
|
|
|
if rate_limited(mail_from, rcpt_tos):
|
|
LOG.w("Rate Limiting applied for mail_from:%s rcpt_tos:%s", mail_from, rcpt_tos)
|
|
|
|
# add more logging info. TODO: remove
|
|
if len(rcpt_tos) == 1:
|
|
alias = Alias.get_by(email=rcpt_tos[0])
|
|
if alias:
|
|
LOG.w(
|
|
"total number email log on %s, %s is %s, %s",
|
|
alias,
|
|
alias.user,
|
|
EmailLog.filter(EmailLog.alias_id == alias.id).count(),
|
|
EmailLog.filter(EmailLog.user_id == alias.user_id).count(),
|
|
)
|
|
|
|
if should_ignore_bounce(envelope.mail_from):
|
|
return status.E207
|
|
else:
|
|
return status.E522
|
|
|
|
# Handle "out-of-office" auto notice, i.e. an automatic response is sent for every forwarded email
|
|
if len(rcpt_tos) == 1 and is_reverse_alias(rcpt_tos[0]) and mail_from == "<>":
|
|
contact = Contact.get_by(reply_email=rcpt_tos[0])
|
|
LOG.w(
|
|
"out-of-office email to reverse alias %s. Saved to %s",
|
|
contact,
|
|
save_email_for_debugging(msg), # todo: remove
|
|
)
|
|
return status.E206
|
|
|
|
# result of all deliveries
|
|
# each element is a couple of whether the delivery is successful and the smtp status
|
|
res: [(bool, str)] = []
|
|
|
|
nb_rcpt_tos = len(rcpt_tos)
|
|
for rcpt_index, rcpt_to in enumerate(rcpt_tos):
|
|
if rcpt_to in config.NOREPLIES:
|
|
LOG.i("email sent to {} address from {}".format(NOREPLY, mail_from))
|
|
send_no_reply_response(mail_from, msg)
|
|
return status.E200
|
|
|
|
# create a copy of msg for each recipient except the last one
|
|
# as copy() is a slow function
|
|
if rcpt_index < nb_rcpt_tos - 1:
|
|
LOG.d("copy message for rcpt %s", rcpt_to)
|
|
copy_msg = copy(msg)
|
|
else:
|
|
copy_msg = msg
|
|
|
|
# Reply case: the recipient is a reverse alias. Used to start with "reply+" or "ra+"
|
|
if is_reverse_alias(rcpt_to):
|
|
LOG.d(
|
|
"Reply phase %s(%s) -> %s", mail_from, copy_msg[headers.FROM], rcpt_to
|
|
)
|
|
is_delivered, smtp_status = handle_reply(envelope, copy_msg, rcpt_to)
|
|
res.append((is_delivered, smtp_status))
|
|
else: # Forward case
|
|
LOG.d(
|
|
"Forward phase %s(%s) -> %s",
|
|
mail_from,
|
|
copy_msg[headers.FROM],
|
|
rcpt_to,
|
|
)
|
|
for is_delivered, smtp_status in handle_forward(
|
|
envelope, copy_msg, rcpt_to
|
|
):
|
|
res.append((is_delivered, smtp_status))
|
|
|
|
# to know whether both successful and unsuccessful deliveries can happen at the same time
|
|
nb_success = len([is_success for (is_success, smtp_status) in res if is_success])
|
|
# ignore E518 which is a normal condition
|
|
nb_non_success = len(
|
|
[
|
|
is_success
|
|
for (is_success, smtp_status) in res
|
|
if not is_success and smtp_status != status.E518
|
|
]
|
|
)
|
|
|
|
if nb_success > 0 and nb_non_success > 0:
|
|
LOG.e(f"some deliveries fail and some success, {mail_from}, {rcpt_tos}, {res}")
|
|
|
|
for (is_success, smtp_status) in res:
|
|
# Consider all deliveries successful if 1 delivery is successful
|
|
if is_success:
|
|
return smtp_status
|
|
|
|
# Failed delivery for all, return the first failure
|
|
return res[0][1]
|
|
|
|
|
|
def handle_out_of_office_reply_phase(email_log, envelope, msg, rcpt_tos):
|
|
"""convert the email into a normal email sent to the alias, so it can be forwarded to mailbox"""
|
|
LOG.d(
|
|
"send the out-of-office email to the alias %s, old to_header:%s rcpt_tos:%s, %s",
|
|
email_log.alias,
|
|
msg[headers.TO],
|
|
rcpt_tos,
|
|
email_log,
|
|
)
|
|
alias_address = email_log.alias.email
|
|
|
|
rcpt_tos[0] = alias_address
|
|
envelope.rcpt_tos = [alias_address]
|
|
|
|
add_or_replace_header(msg, headers.TO, alias_address)
|
|
# delete reply-to header that can affect email delivery
|
|
delete_header(msg, headers.REPLY_TO)
|
|
|
|
LOG.d(
|
|
"after out-of-office transformation to_header:%s reply_to:%s rcpt_tos:%s",
|
|
msg.get_all(headers.TO),
|
|
msg.get_all(headers.REPLY_TO),
|
|
rcpt_tos,
|
|
)
|
|
|
|
|
|
def handle_out_of_office_forward_phase(email_log, envelope, msg, rcpt_tos):
|
|
"""convert the email into a normal email sent to the reverse alias, so it can be forwarded to contact"""
|
|
LOG.d(
|
|
"send the out-of-office email to the contact %s, old to_header:%s rcpt_tos:%s %s",
|
|
email_log.contact,
|
|
msg[headers.TO],
|
|
rcpt_tos,
|
|
email_log,
|
|
)
|
|
reverse_alias = email_log.contact.reply_email
|
|
|
|
rcpt_tos[0] = reverse_alias
|
|
envelope.rcpt_tos = [reverse_alias]
|
|
|
|
add_or_replace_header(msg, headers.TO, reverse_alias)
|
|
# delete reply-to header that can affect email delivery
|
|
delete_header(msg, headers.REPLY_TO)
|
|
|
|
LOG.d(
|
|
"after out-of-office transformation to_header:%s reply_to:%s rcpt_tos:%s",
|
|
msg.get_all(headers.TO),
|
|
msg.get_all(headers.REPLY_TO),
|
|
rcpt_tos,
|
|
)
|
|
|
|
|
|
class MailHandler:
|
|
async def handle_DATA(self, server, session, envelope: Envelope):
|
|
msg = email.message_from_bytes(envelope.original_content)
|
|
try:
|
|
ret = self._handle(envelope, msg)
|
|
return ret
|
|
|
|
# happen if reverse-alias is used during the forward phase
|
|
# as in this case, a new reverse-alias needs to be created for this reverse-alias -> chaos
|
|
except CannotCreateContactForReverseAlias as e:
|
|
LOG.w(
|
|
"Probably due to reverse-alias used in the forward phase, "
|
|
"error:%s mail_from:%s, rcpt_tos:%s, header_from:%s, header_to:%s",
|
|
e,
|
|
envelope.mail_from,
|
|
envelope.rcpt_tos,
|
|
msg[headers.FROM],
|
|
msg[headers.TO],
|
|
)
|
|
return status.E524
|
|
except (VERPReply, VERPForward, VERPTransactional) as e:
|
|
LOG.w(
|
|
"email handling fail with error:%s "
|
|
"mail_from:%s, rcpt_tos:%s, header_from:%s, header_to:%s",
|
|
e,
|
|
envelope.mail_from,
|
|
envelope.rcpt_tos,
|
|
msg[headers.FROM],
|
|
msg[headers.TO],
|
|
)
|
|
return status.E213
|
|
except Exception as e:
|
|
LOG.e(
|
|
"email handling fail with error:%s "
|
|
"mail_from:%s, rcpt_tos:%s, header_from:%s, header_to:%s, saved to %s",
|
|
e,
|
|
envelope.mail_from,
|
|
envelope.rcpt_tos,
|
|
msg[headers.FROM],
|
|
msg[headers.TO],
|
|
save_envelope_for_debugging(
|
|
envelope, file_name_prefix=e.__class__.__name__
|
|
), # todo: remove
|
|
)
|
|
return status.E404
|
|
|
|
@newrelic.agent.background_task()
|
|
def _handle(self, envelope: Envelope, msg: Message):
|
|
start = time.time()
|
|
|
|
# generate a different message_id to keep track of an email lifecycle
|
|
message_id = str(uuid.uuid4())
|
|
set_message_id(message_id)
|
|
|
|
LOG.d("====>=====>====>====>====>====>====>====>")
|
|
LOG.i(
|
|
"New message, mail from %s, rctp tos %s ",
|
|
envelope.mail_from,
|
|
envelope.rcpt_tos,
|
|
)
|
|
newrelic.agent.record_custom_metric(
|
|
"Custom/nb_rcpt_tos", len(envelope.rcpt_tos)
|
|
)
|
|
|
|
with create_light_app().app_context():
|
|
return_status = handle(envelope, msg)
|
|
elapsed = time.time() - start
|
|
# Only bounce messages if the return-path passes the spf check. Otherwise black-hole it.
|
|
spamd_result = SpamdResult.extract_from_headers(msg)
|
|
if return_status[0] == "5":
|
|
if spamd_result and spamd_result.spf in (
|
|
SPFCheckResult.fail,
|
|
SPFCheckResult.soft_fail,
|
|
):
|
|
LOG.i(
|
|
"Replacing 5XX to 216 status because the return-path failed the spf check"
|
|
)
|
|
return_status = status.E216
|
|
|
|
LOG.i(
|
|
"Finish mail_from %s, rcpt_tos %s, takes %s seconds with return code '%s'<<===",
|
|
envelope.mail_from,
|
|
envelope.rcpt_tos,
|
|
elapsed,
|
|
return_status,
|
|
)
|
|
|
|
SpamdResult.send_to_new_relic(msg)
|
|
newrelic.agent.record_custom_metric("Custom/email_handler_time", elapsed)
|
|
newrelic.agent.record_custom_metric("Custom/number_incoming_email", 1)
|
|
return return_status
|
|
|
|
|
|
def main(port: int):
|
|
"""Use aiosmtpd Controller"""
|
|
controller = Controller(MailHandler(), hostname="0.0.0.0", port=port)
|
|
|
|
controller.start()
|
|
LOG.d("Start mail controller %s %s", controller.hostname, controller.port)
|
|
|
|
if LOAD_PGP_EMAIL_HANDLER:
|
|
LOG.w("LOAD PGP keys")
|
|
load_pgp_public_keys()
|
|
|
|
while True:
|
|
time.sleep(2)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
parser = argparse.ArgumentParser()
|
|
parser.add_argument(
|
|
"-p", "--port", help="SMTP port to listen for", type=int, default=20381
|
|
)
|
|
args = parser.parse_args()
|
|
|
|
LOG.i("Listen for port %s", args.port)
|
|
main(port=args.port)
|