963 lines
30 KiB
Python
963 lines
30 KiB
Python
"""
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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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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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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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import time
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import uuid
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from email import encoders
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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.parser import Parser
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from email.policy import SMTPUTF8
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from email.utils import parseaddr
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from io import BytesIO
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from smtplib import SMTP
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from typing import Optional
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from aiosmtpd.controller import Controller
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from app import pgp_utils, s3
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from app.config import (
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EMAIL_DOMAIN,
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POSTFIX_SERVER,
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URL,
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ALIAS_DOMAINS,
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POSTFIX_SUBMISSION_TLS,
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UNSUBSCRIBER,
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)
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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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get_email_domain_part,
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add_or_replace_header,
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delete_header,
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send_cannot_create_directory_alias,
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send_cannot_create_domain_alias,
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email_belongs_to_alias_domains,
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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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new_addr,
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get_addrs_from_header,
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get_spam_info,
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get_orig_message_from_spamassassin_report,
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)
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from app.extensions import db
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from app.log import LOG
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from app.models import (
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Alias,
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Contact,
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EmailLog,
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CustomDomain,
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Directory,
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User,
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DeletedAlias,
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RefusedEmail,
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)
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from app.utils import random_string
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from server import create_app
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# fix the database connection leak issue
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# use this method instead of create_app
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def new_app():
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app = create_app()
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@app.teardown_appcontext
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def shutdown_session(response_or_exc):
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# same as shutdown_session() in flask-sqlalchemy but this is not enough
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db.session.remove()
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# dispose the engine too
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db.engine.dispose()
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return app
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def try_auto_create(address: str) -> Optional[Alias]:
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"""Try to auto-create the alias using directory or catch-all domain
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"""
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alias = try_auto_create_catch_all_domain(address)
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if not alias:
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alias = try_auto_create_directory(address)
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return alias
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def try_auto_create_directory(address: str) -> Optional[Alias]:
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"""
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Try to create an alias with directory
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"""
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# check if alias belongs to a directory, ie having directory/anything@EMAIL_DOMAIN format
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if email_belongs_to_alias_domains(address):
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# if there's no directory separator in the alias, no way to auto-create it
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if "/" not in address and "+" not in address and "#" not in address:
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return None
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# alias contains one of the 3 special directory separator: "/", "+" or "#"
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if "/" in address:
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sep = "/"
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elif "+" in address:
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sep = "+"
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else:
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sep = "#"
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directory_name = address[: address.find(sep)]
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LOG.d("directory_name %s", directory_name)
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directory = Directory.get_by(name=directory_name)
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if not directory:
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return None
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dir_user: User = directory.user
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if not dir_user.can_create_new_alias():
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send_cannot_create_directory_alias(dir_user, address, directory_name)
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return None
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# if alias has been deleted before, do not auto-create it
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if DeletedAlias.get_by(email=address, user_id=directory.user_id):
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LOG.warning(
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"Alias %s was deleted before, cannot auto-create using directory %s, user %s",
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address,
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directory_name,
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dir_user,
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)
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return None
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LOG.d("create alias %s for directory %s", address, directory)
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alias = Alias.create(
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email=address,
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user_id=directory.user_id,
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directory_id=directory.id,
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mailbox_id=dir_user.default_mailbox_id,
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)
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db.session.commit()
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return alias
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def try_auto_create_catch_all_domain(address: str) -> Optional[Alias]:
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"""Try to create an alias with catch-all domain"""
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# try to create alias on-the-fly with custom-domain catch-all feature
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# check if alias is custom-domain alias and if the custom-domain has catch-all enabled
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alias_domain = get_email_domain_part(address)
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custom_domain = CustomDomain.get_by(domain=alias_domain)
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if not custom_domain:
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return None
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# custom_domain exists
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if not custom_domain.catch_all:
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return None
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# custom_domain has catch-all enabled
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domain_user: User = custom_domain.user
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if not domain_user.can_create_new_alias():
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send_cannot_create_domain_alias(domain_user, address, alias_domain)
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return None
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# if alias has been deleted before, do not auto-create it
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if DeletedAlias.get_by(email=address, user_id=custom_domain.user_id):
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LOG.warning(
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"Alias %s was deleted before, cannot auto-create using domain catch-all %s, user %s",
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address,
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custom_domain,
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domain_user,
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)
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return None
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LOG.d("create alias %s for domain %s", address, custom_domain)
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alias = Alias.create(
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email=address,
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user_id=custom_domain.user_id,
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custom_domain_id=custom_domain.id,
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automatic_creation=True,
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mailbox_id=domain_user.default_mailbox_id,
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)
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db.session.commit()
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return alias
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def get_or_create_contact(website_from_header: str, alias: Alias) -> Contact:
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"""
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website_from_header can be the full-form email, i.e. "First Last <email@example.com>"
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"""
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_, website_email = parseaddr(website_from_header)
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contact = Contact.get_by(alias_id=alias.id, website_email=website_email)
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if contact:
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# update the website_from if needed
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if contact.website_from != website_from_header:
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LOG.d("Update From header for %s", contact)
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contact.website_from = website_from_header
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db.session.commit()
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else:
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LOG.debug(
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"create forward email for alias %s and website email %s",
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alias,
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website_from_header,
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)
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reply_email = generate_reply_email()
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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=website_email,
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website_from=website_from_header,
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reply_email=reply_email,
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)
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db.session.commit()
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return contact
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def replace_header_when_forward(msg: Message, alias: Alias, header: str):
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"""
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Replace CC or To header by Reply emails in forward phase
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"""
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addrs = get_addrs_from_header(msg, header)
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# Nothing to do
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if not addrs:
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return
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new_addrs: [str] = []
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need_replace = False
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for addr in addrs:
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name, email = parseaddr(addr)
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# no transformation when alias is already in the header
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if email == alias.email:
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new_addrs.append(addr)
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continue
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contact = Contact.get_by(alias_id=alias.id, website_email=email)
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if contact:
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# update the website_from if needed
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if contact.website_from != addr:
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LOG.d("Update website_from for %s to %s", contact, addr)
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contact.website_from = addr
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db.session.commit()
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else:
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LOG.debug(
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"create contact for alias %s and email %s, header %s",
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alias,
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email,
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header,
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)
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reply_email = generate_reply_email()
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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=email,
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website_from=addr,
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reply_email=reply_email,
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is_cc=header.lower() == "cc",
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)
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db.session.commit()
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new_addrs.append(
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new_addr(contact.website_from, contact.reply_email, alias.user)
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)
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need_replace = True
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if need_replace:
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new_header = ",".join(new_addrs)
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LOG.d("Replace %s header, old: %s, new: %s", header, msg[header], new_header)
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add_or_replace_header(msg, header, new_header)
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else:
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LOG.d("No need to replace %s header", header)
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def replace_header_when_reply(msg: Message, alias: Alias, header: str):
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"""
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Replace CC or To Reply emails by original emails
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"""
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addrs = get_addrs_from_header(msg, header)
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# Nothing to do
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if not addrs:
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return
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new_addrs: [str] = []
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for addr in addrs:
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name, email = parseaddr(addr)
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# no transformation when alias is already in the header
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if email == alias.email:
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continue
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contact = Contact.get_by(reply_email=email)
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if not contact:
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LOG.warning(
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"%s email in reply phase %s must be reply emails", header, email
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)
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# still keep this email in header
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new_addrs.append(addr)
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continue
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new_addrs.append(contact.website_from or contact.website_email)
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new_header = ",".join(new_addrs)
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LOG.d("Replace %s header, old: %s, new: %s", header, msg[header], new_header)
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add_or_replace_header(msg, header, new_header)
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def generate_reply_email():
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# generate a reply_email, make sure it is unique
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# not use while loop to avoid infinite loop
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reply_email = f"reply+{random_string(30)}@{EMAIL_DOMAIN}"
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for _ in range(1000):
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if not Contact.get_by(reply_email=reply_email):
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# found!
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break
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reply_email = f"reply+{random_string(30)}@{EMAIL_DOMAIN}"
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return reply_email
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def should_append_alias(msg: Message, address: str):
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"""whether an alias should be appended to TO header in message"""
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if msg["To"] and address in msg["To"]:
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return False
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if msg["Cc"] and address in msg["Cc"]:
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return False
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return True
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def prepare_pgp_message(orig_msg: Message, pgp_fingerprint: str):
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msg = MIMEMultipart("encrypted", protocol="application/pgp-encrypted")
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# copy all headers from original message except the "Content-Type"
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for i in reversed(range(len(orig_msg._headers))):
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header_name = orig_msg._headers[i][0].lower()
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if header_name != "Content-Type".lower():
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msg[header_name] = orig_msg._headers[i][1]
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# Delete unnecessary headers in orig_msg except to save space
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delete_all_headers_except(
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orig_msg,
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[
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"MIME-Version",
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"Content-Type",
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"Content-Disposition",
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"Content-Transfer-Encoding",
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],
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)
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first = MIMEApplication(
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_subtype="pgp-encrypted", _encoder=encoders.encode_7or8bit, _data=""
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)
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first.set_payload("Version: 1")
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msg.attach(first)
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second = MIMEApplication("octet-stream", _encoder=encoders.encode_7or8bit)
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second.add_header("Content-Disposition", "inline")
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# encrypt original message
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encrypted_data = pgp_utils.encrypt(orig_msg.as_string(), pgp_fingerprint)
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second.set_payload(encrypted_data)
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msg.attach(second)
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return msg
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def handle_forward(envelope, smtp: SMTP, msg: Message, rcpt_to: str) -> (bool, str):
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"""return whether an email has been delivered and
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the smtp status ("250 Message accepted", "550 Non-existent email address", etc)
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"""
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address = rcpt_to.lower() # alias@SL
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alias = Alias.get_by(email=address)
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if not alias:
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LOG.d("alias %s not exist. Try to see if it can be created on the fly", address)
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alias = try_auto_create(address)
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if not alias:
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LOG.d("alias %s cannot be created on-the-fly, return 550", address)
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return False, "550 SL Email not exist"
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mailbox = alias.mailbox
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mailbox_email = mailbox.email
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user = alias.user
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# Sometimes when user clicks on "reply all"
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# an email is sent to the same alias that the previous message is destined to
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if envelope.mail_from == mailbox_email:
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# nothing to do
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LOG.d("Forward from %s to %s, nothing to do", envelope.mail_from, mailbox_email)
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return False, "550 SL ignored"
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contact = get_or_create_contact(msg["From"], alias)
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spam_check = True
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# create PGP email if needed
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if mailbox.pgp_finger_print and user.is_premium():
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LOG.d("Encrypt message using mailbox %s", mailbox)
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msg = prepare_pgp_message(msg, mailbox.pgp_finger_print)
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# no need to spam check for encrypted message
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spam_check = False
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if spam_check:
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is_spam, spam_status = get_spam_info(msg)
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if is_spam:
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LOG.warning("Email detected as spam. Alias: %s, from: %s", alias, contact)
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handle_spam(contact, alias, msg, user, mailbox_email, spam_status)
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return False, "550 SL ignored"
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forward_log = EmailLog.create(contact_id=contact.id, user_id=contact.user_id)
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if alias.enabled:
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# add custom header
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add_or_replace_header(msg, "X-SimpleLogin-Type", "Forward")
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# remove reply-to & sender header if present
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delete_header(msg, "Reply-To")
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delete_header(msg, "Sender")
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# change the from header so the sender comes from @SL
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# so it can pass DMARC check
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# replace the email part in from: header
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contact_from_header = msg["From"]
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contact_name, contact_email = parseaddr(contact_from_header)
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new_from_header = new_addr(contact_from_header, contact.reply_email, user)
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add_or_replace_header(msg, "From", new_from_header)
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LOG.d("new_from_header:%s, old header %s", new_from_header, contact_from_header)
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# replace CC & To emails by reply-email for all emails that are not alias
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replace_header_when_forward(msg, alias, "Cc")
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replace_header_when_forward(msg, alias, "To")
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# append alias into the TO header if it's not present in To or CC
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if should_append_alias(msg, alias.email):
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LOG.d("append alias %s to TO header %s", alias, msg["To"])
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if msg["To"]:
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to_header = msg["To"] + "," + alias.email
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else:
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to_header = alias.email
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add_or_replace_header(msg, "To", to_header.strip())
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# add List-Unsubscribe header
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if UNSUBSCRIBER:
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unsubscribe_link = f"mailto:{UNSUBSCRIBER}?subject={alias.id}="
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add_or_replace_header(msg, "List-Unsubscribe", f"<{unsubscribe_link}>")
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else:
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unsubscribe_link = f"{URL}/dashboard/unsubscribe/{alias.id}"
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add_or_replace_header(msg, "List-Unsubscribe", f"<{unsubscribe_link}>")
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add_or_replace_header(
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msg, "List-Unsubscribe-Post", "List-Unsubscribe=One-Click"
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)
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add_dkim_signature(msg, EMAIL_DOMAIN)
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LOG.d(
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"Forward mail from %s to %s, mail_options %s, rcpt_options %s ",
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contact_email,
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mailbox_email,
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envelope.mail_options,
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envelope.rcpt_options,
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)
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# smtp.send_message has UnicodeEncodeErroremail issue
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# encode message raw directly instead
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msg_raw = msg.as_string().encode()
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smtp.sendmail(
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contact.reply_email,
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mailbox_email,
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msg_raw,
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envelope.mail_options,
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envelope.rcpt_options,
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)
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else:
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LOG.d("%s is disabled, do not forward", alias)
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forward_log.blocked = True
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db.session.commit()
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return True, "250 Message accepted for delivery"
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|
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def handle_reply(envelope, smtp: SMTP, msg: Message, rcpt_to: str) -> (bool, str):
|
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"""
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return whether an email has been delivered and
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the smtp status ("250 Message accepted", "550 Non-existent email address", etc)
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"""
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reply_email = rcpt_to.lower()
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# reply_email must end with EMAIL_DOMAIN
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if not reply_email.endswith(EMAIL_DOMAIN):
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LOG.warning(f"Reply email {reply_email} has wrong domain")
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return False, "550 SL wrong reply email"
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contact = Contact.get_by(reply_email=reply_email)
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if not contact:
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LOG.warning(f"No such forward-email with {reply_email} as reply-email")
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return False, "550 SL wrong reply email"
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|
|
|
alias = contact.alias
|
|
address: str = contact.alias.email
|
|
alias_domain = address[address.find("@") + 1 :]
|
|
|
|
# alias must end with one of the ALIAS_DOMAINS or custom-domain
|
|
if not email_belongs_to_alias_domains(alias.email):
|
|
if not CustomDomain.get_by(domain=alias_domain):
|
|
return False, "550 SL alias unknown by SimpleLogin"
|
|
|
|
user = alias.user
|
|
mailbox_email = alias.mailbox_email()
|
|
|
|
# bounce email initiated by Postfix
|
|
# can happen in case emails cannot be delivered to user-email
|
|
# in this case Postfix will try to send a bounce report to original sender, which is
|
|
# the "reply email"
|
|
if envelope.mail_from == "<>":
|
|
LOG.warning(
|
|
"Bounce when sending to alias %s from %s, user %s",
|
|
alias,
|
|
contact.website_from,
|
|
alias.user,
|
|
)
|
|
|
|
handle_bounce(contact, alias, msg, user, mailbox_email)
|
|
return False, "550 SL ignored"
|
|
|
|
# only mailbox can send email to the reply-email
|
|
if envelope.mail_from.lower() != mailbox_email.lower():
|
|
LOG.warning(
|
|
f"Reply email can only be used by mailbox. "
|
|
f"Actual mail_from: %s. msg from header: %s, Mailbox %s. reply_email %s",
|
|
envelope.mail_from,
|
|
msg["From"],
|
|
mailbox_email,
|
|
reply_email,
|
|
)
|
|
|
|
send_email(
|
|
mailbox_email,
|
|
f"Reply from your alias {alias.email} only works from your mailbox",
|
|
render(
|
|
"transactional/reply-must-use-personal-email.txt",
|
|
name=user.name,
|
|
alias=alias.email,
|
|
sender=envelope.mail_from,
|
|
mailbox_email=mailbox_email,
|
|
),
|
|
render(
|
|
"transactional/reply-must-use-personal-email.html",
|
|
name=user.name,
|
|
alias=alias.email,
|
|
sender=envelope.mail_from,
|
|
mailbox_email=mailbox_email,
|
|
),
|
|
)
|
|
|
|
# Notify sender that they cannot send emails to this address
|
|
send_email(
|
|
envelope.mail_from,
|
|
f"Your email ({envelope.mail_from}) is not allowed to send emails to {reply_email}",
|
|
render(
|
|
"transactional/send-from-alias-from-unknown-sender.txt",
|
|
sender=envelope.mail_from,
|
|
reply_email=reply_email,
|
|
),
|
|
"",
|
|
)
|
|
|
|
return False, "550 SL ignored"
|
|
|
|
delete_header(msg, "DKIM-Signature")
|
|
|
|
delete_header(msg, "Received")
|
|
|
|
# make the email comes from alias
|
|
add_or_replace_header(msg, "From", alias.email)
|
|
|
|
# some email providers like ProtonMail adds automatically the Reply-To field
|
|
# make sure to delete it
|
|
delete_header(msg, "Reply-To")
|
|
|
|
# remove sender header if present as this could reveal user real email
|
|
delete_header(msg, "Sender")
|
|
|
|
replace_header_when_reply(msg, alias, "To")
|
|
replace_header_when_reply(msg, alias, "Cc")
|
|
|
|
# Received-SPF is injected by postfix-policyd-spf-python can reveal user original email
|
|
delete_header(msg, "Received-SPF")
|
|
|
|
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 alias_domain in ALIAS_DOMAINS:
|
|
add_dkim_signature(msg, alias_domain)
|
|
# add DKIM-Signature for custom-domain alias
|
|
else:
|
|
custom_domain: CustomDomain = CustomDomain.get_by(domain=alias_domain)
|
|
if custom_domain.dkim_verified:
|
|
add_dkim_signature(msg, alias_domain)
|
|
|
|
msg_raw = msg.as_string().encode()
|
|
smtp.sendmail(
|
|
alias.email,
|
|
contact.website_email,
|
|
msg_raw,
|
|
envelope.mail_options,
|
|
envelope.rcpt_options,
|
|
)
|
|
|
|
EmailLog.create(contact_id=contact.id, is_reply=True, user_id=contact.user_id)
|
|
db.session.commit()
|
|
|
|
return True, "250 Message accepted for delivery"
|
|
|
|
|
|
def handle_bounce(
|
|
contact: Contact, alias: Alias, msg: Message, user: User, mailbox_email: str
|
|
):
|
|
address = alias.email
|
|
fel: EmailLog = EmailLog.create(
|
|
contact_id=contact.id, bounced=True, user_id=contact.user_id
|
|
)
|
|
db.session.commit()
|
|
|
|
nb_bounced = EmailLog.filter_by(contact_id=contact.id, bounced=True).count()
|
|
disable_alias_link = f"{URL}/dashboard/unsubscribe/{alias.id}"
|
|
|
|
# Store the bounced email
|
|
orig_msg = get_orig_message_from_bounce(msg)
|
|
# 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(msg.as_bytes()), random_name)
|
|
|
|
file_path = None
|
|
if orig_msg:
|
|
file_path = f"refused-emails/{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
file_path, BytesIO(orig_msg.as_bytes()), random_name
|
|
)
|
|
|
|
refused_email = RefusedEmail.create(
|
|
path=file_path, full_report_path=full_report_path, user_id=user.id
|
|
)
|
|
db.session.flush()
|
|
|
|
fel.refused_email_id = refused_email.id
|
|
db.session.commit()
|
|
|
|
LOG.d("Create refused email %s", refused_email)
|
|
|
|
refused_email_url = URL + f"/dashboard/refused_email?highlight_id=" + str(fel.id)
|
|
|
|
# inform user if this is the first bounced email
|
|
if nb_bounced == 1:
|
|
LOG.d(
|
|
"Inform user %s about bounced email sent by %s to alias %s",
|
|
user,
|
|
contact.website_from,
|
|
address,
|
|
)
|
|
send_email(
|
|
# use user mail here as only user is authenticated to see the refused email
|
|
user.email,
|
|
f"Email from {contact.website_from} to {address} cannot be delivered to your inbox",
|
|
render(
|
|
"transactional/bounced-email.txt",
|
|
name=user.name,
|
|
alias=alias,
|
|
website_from=contact.website_from,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox_email,
|
|
),
|
|
render(
|
|
"transactional/bounced-email.html",
|
|
name=user.name,
|
|
alias=alias,
|
|
website_from=contact.website_from,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox_email,
|
|
),
|
|
# cannot include bounce email as it can contain spammy text
|
|
# bounced_email=msg,
|
|
)
|
|
# disable the alias the second time email is bounced
|
|
elif nb_bounced >= 2:
|
|
LOG.d(
|
|
"Bounce happens again with alias %s from %s. Disable alias now ",
|
|
address,
|
|
contact.website_from,
|
|
)
|
|
alias.enabled = False
|
|
db.session.commit()
|
|
|
|
send_email(
|
|
# use user mail here as only user is authenticated to see the refused email
|
|
user.email,
|
|
f"Alias {address} has been disabled due to second undelivered email from {contact.website_from}",
|
|
render(
|
|
"transactional/automatic-disable-alias.txt",
|
|
name=user.name,
|
|
alias=alias,
|
|
website_from=contact.website_from,
|
|
website_email=contact.website_email,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox_email,
|
|
),
|
|
render(
|
|
"transactional/automatic-disable-alias.html",
|
|
name=user.name,
|
|
alias=alias,
|
|
website_from=contact.website_from,
|
|
website_email=contact.website_email,
|
|
refused_email_url=refused_email_url,
|
|
mailbox_email=mailbox_email,
|
|
),
|
|
# cannot include bounce email as it can contain spammy text
|
|
# bounced_email=msg,
|
|
)
|
|
|
|
|
|
def handle_spam(
|
|
contact: Contact,
|
|
alias: Alias,
|
|
msg: Message,
|
|
user: User,
|
|
mailbox_email: str,
|
|
spam_status: str,
|
|
):
|
|
email_log: EmailLog = EmailLog.create(
|
|
contact_id=contact.id,
|
|
user_id=contact.user_id,
|
|
is_spam=True,
|
|
spam_status=spam_status,
|
|
)
|
|
db.session.commit()
|
|
|
|
# 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"refused-emails/full-{random_name}.eml"
|
|
s3.upload_email_from_bytesio(full_report_path, BytesIO(msg.as_bytes()), random_name)
|
|
|
|
file_path = None
|
|
if orig_msg:
|
|
file_path = f"refused-emails/{random_name}.eml"
|
|
s3.upload_email_from_bytesio(
|
|
file_path, BytesIO(orig_msg.as_bytes()), random_name
|
|
)
|
|
|
|
refused_email = RefusedEmail.create(
|
|
path=file_path, full_report_path=full_report_path, user_id=user.id
|
|
)
|
|
db.session.flush()
|
|
|
|
email_log.refused_email_id = refused_email.id
|
|
db.session.commit()
|
|
|
|
LOG.d("Create spam email %s", refused_email)
|
|
|
|
refused_email_url = (
|
|
URL + f"/dashboard/refused_email?highlight_id=" + str(email_log.id)
|
|
)
|
|
disable_alias_link = f"{URL}/dashboard/unsubscribe/{alias.id}"
|
|
|
|
# inform user
|
|
LOG.d(
|
|
"Inform user %s about spam email sent by %s to alias %s",
|
|
user,
|
|
contact.website_from,
|
|
alias.email,
|
|
)
|
|
send_email(
|
|
mailbox_email,
|
|
f"Email from {contact.website_from} to {alias.email} is detected as spam",
|
|
render(
|
|
"transactional/spam-email.txt",
|
|
name=user.name,
|
|
alias=alias,
|
|
website_from=contact.website_from,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
render(
|
|
"transactional/spam-email.html",
|
|
name=user.name,
|
|
alias=alias,
|
|
website_from=contact.website_from,
|
|
website_email=contact.website_email,
|
|
disable_alias_link=disable_alias_link,
|
|
refused_email_url=refused_email_url,
|
|
),
|
|
)
|
|
|
|
|
|
def handle_unsubscribe(envelope):
|
|
message_data = envelope.content.decode("utf8", errors="replace")
|
|
msg = Parser(policy=SMTPUTF8).parsestr(message_data)
|
|
|
|
# format: alias_id:
|
|
subject = msg["Subject"]
|
|
try:
|
|
alias_id = int(subject[:-1])
|
|
alias = Alias.get(alias_id)
|
|
except Exception:
|
|
LOG.warning("Cannot parse alias from subject %s", msg["Subject"])
|
|
return "550 SL ignored"
|
|
|
|
if not alias:
|
|
LOG.warning("No such alias %s", alias_id)
|
|
return "550 SL ignored"
|
|
|
|
# This sender cannot unsubscribe
|
|
if alias.mailbox_email() != envelope.mail_from:
|
|
LOG.d("%s cannot disable alias %s", envelope.mail_from, alias)
|
|
return "550 SL ignored"
|
|
|
|
# Sender is owner of this alias
|
|
alias.enabled = False
|
|
db.session.commit()
|
|
user = alias.user
|
|
|
|
enable_alias_url = URL + f"/dashboard/?highlight_alias_id={alias.id}"
|
|
send_email(
|
|
envelope.mail_from,
|
|
f"Alias {alias.email} has been disabled successfully",
|
|
render(
|
|
"transactional/unsubscribe-disable-alias.txt",
|
|
user=user,
|
|
alias=alias.email,
|
|
enable_alias_url=enable_alias_url,
|
|
),
|
|
render(
|
|
"transactional/unsubscribe-disable-alias.html",
|
|
user=user,
|
|
alias=alias.email,
|
|
enable_alias_url=enable_alias_url,
|
|
),
|
|
)
|
|
|
|
return "250 Unsubscribe request accepted"
|
|
|
|
|
|
class MailHandler:
|
|
async def handle_DATA(self, server, session, envelope):
|
|
LOG.debug(
|
|
"===>> New message, mail from %s, rctp tos %s ",
|
|
envelope.mail_from,
|
|
envelope.rcpt_tos,
|
|
)
|
|
|
|
if POSTFIX_SUBMISSION_TLS:
|
|
smtp = SMTP(POSTFIX_SERVER, 587)
|
|
smtp.starttls()
|
|
else:
|
|
smtp = SMTP(POSTFIX_SERVER, 25)
|
|
|
|
# unsubscribe request
|
|
if UNSUBSCRIBER and envelope.rcpt_tos == [UNSUBSCRIBER]:
|
|
LOG.d("Handle unsubscribe request from %s", envelope.mail_from)
|
|
app = new_app()
|
|
|
|
with app.app_context():
|
|
return handle_unsubscribe(envelope)
|
|
|
|
# result of all deliveries
|
|
# each element is a couple of whether the delivery is successful and the smtp status
|
|
res: [(bool, str)] = []
|
|
|
|
for rcpt_to in envelope.rcpt_tos:
|
|
message_data = envelope.content.decode("utf8", errors="replace")
|
|
msg = Parser(policy=SMTPUTF8).parsestr(message_data)
|
|
|
|
# Reply case
|
|
# recipient starts with "reply+" or "ra+" (ra=reverse-alias) prefix
|
|
if rcpt_to.startswith("reply+") or rcpt_to.startswith("ra+"):
|
|
LOG.debug(">>> Reply phase %s -> %s", envelope.mail_from, rcpt_to)
|
|
app = new_app()
|
|
|
|
with app.app_context():
|
|
is_delivered, smtp_status = handle_reply(
|
|
envelope, smtp, msg, rcpt_to
|
|
)
|
|
res.append((is_delivered, smtp_status))
|
|
else: # Forward case
|
|
LOG.debug(">>> Forward phase %s -> %s", envelope.mail_from, rcpt_to)
|
|
app = new_app()
|
|
|
|
with app.app_context():
|
|
is_delivered, smtp_status = handle_forward(
|
|
envelope, smtp, msg, rcpt_to
|
|
)
|
|
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]
|
|
|
|
|
|
if __name__ == "__main__":
|
|
controller = Controller(MailHandler(), hostname="0.0.0.0", port=20381)
|
|
|
|
controller.start()
|
|
LOG.d("Start mail controller %s %s", controller.hostname, controller.port)
|
|
|
|
while True:
|
|
time.sleep(2)
|