mirror of
https://github.com/simple-login/app.git
synced 2024-09-04 09:31:30 +02:00
930 lines
27 KiB
Python
930 lines
27 KiB
Python
import base64
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import email
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import enum
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import os
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import quopri
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import random
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import re
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from email.header import decode_header
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from email.message import Message
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from email.mime.multipart import MIMEMultipart
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from email.mime.text import MIMEText
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from email.utils import make_msgid, formatdate, parseaddr
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from smtplib import SMTP
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import arrow
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import dkim
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from jinja2 import Environment, FileSystemLoader
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from validate_email import validate_email
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from app.config import (
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SUPPORT_EMAIL,
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ROOT_DIR,
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POSTFIX_SERVER,
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NOT_SEND_EMAIL,
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DKIM_SELECTOR,
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DKIM_PRIVATE_KEY,
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DKIM_HEADERS,
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ALIAS_DOMAINS,
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SUPPORT_NAME,
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POSTFIX_SUBMISSION_TLS,
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MAX_NB_EMAIL_FREE_PLAN,
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DISPOSABLE_EMAIL_DOMAINS,
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MAX_ALERT_24H,
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POSTFIX_PORT,
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SENDER,
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URL,
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LANDING_PAGE_URL,
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EMAIL_DOMAIN,
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ALERT_DIRECTORY_DISABLED_ALIAS_CREATION,
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)
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from app.dns_utils import get_mx_domains
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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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Mailbox,
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User,
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SentAlert,
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CustomDomain,
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SLDomain,
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Contact,
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Alias,
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EmailLog,
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)
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from app.utils import random_string, convert_to_id, convert_to_alphanumeric
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def render(template_name, **kwargs) -> str:
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templates_dir = os.path.join(ROOT_DIR, "templates", "emails")
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env = Environment(loader=FileSystemLoader(templates_dir))
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template = env.get_template(template_name)
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return template.render(
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MAX_NB_EMAIL_FREE_PLAN=MAX_NB_EMAIL_FREE_PLAN,
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URL=URL,
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LANDING_PAGE_URL=LANDING_PAGE_URL,
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**kwargs,
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)
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def send_welcome_email(user):
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to_email, unsubscribe_link, via_email = user.get_communication_email()
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if not to_email:
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return
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# whether this email is sent to an alias
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alias = to_email if to_email != user.email else None
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send_email(
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to_email,
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f"Welcome to SimpleLogin {user.name}",
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render("com/welcome.txt", name=user.name, user=user, alias=alias),
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render("com/welcome.html", name=user.name, user=user, alias=alias),
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unsubscribe_link,
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via_email,
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)
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def send_trial_end_soon_email(user):
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send_email(
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user.email,
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f"Your trial will end soon {user.name}",
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render("transactional/trial-end.txt", name=user.name, user=user),
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render("transactional/trial-end.html", name=user.name, user=user),
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)
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def send_activation_email(email, name, activation_link):
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send_email(
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email,
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f"Just one more step to join SimpleLogin {name}",
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render(
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"transactional/activation.txt",
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name=name,
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activation_link=activation_link,
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email=email,
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),
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render(
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"transactional/activation.html",
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name=name,
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activation_link=activation_link,
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email=email,
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),
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)
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def send_reset_password_email(email, name, reset_password_link):
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send_email(
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email,
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"Reset your password on SimpleLogin",
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render(
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"transactional/reset-password.txt",
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name=name,
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reset_password_link=reset_password_link,
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),
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render(
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"transactional/reset-password.html",
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name=name,
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reset_password_link=reset_password_link,
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),
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)
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def send_change_email(new_email, current_email, name, link):
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send_email(
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new_email,
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"Confirm email update on SimpleLogin",
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render(
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"transactional/change-email.txt",
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name=name,
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link=link,
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new_email=new_email,
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current_email=current_email,
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),
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render(
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"transactional/change-email.html",
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name=name,
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link=link,
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new_email=new_email,
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current_email=current_email,
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),
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)
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def send_test_email_alias(email, name):
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send_email(
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email,
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f"This email is sent to {email}",
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render("transactional/test-email.txt", name=name, alias=email),
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render("transactional/test-email.html", name=name, alias=email),
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)
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def send_cannot_create_directory_alias(user, alias_address, directory_name):
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"""when user cancels their subscription, they cannot create alias on the fly.
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If this happens, send them an email to notify
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"""
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send_email(
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user.email,
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f"Alias {alias_address} cannot be created",
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render(
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"transactional/cannot-create-alias-directory.txt",
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name=user.name,
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alias=alias_address,
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directory=directory_name,
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),
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render(
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"transactional/cannot-create-alias-directory.html",
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name=user.name,
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alias=alias_address,
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directory=directory_name,
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),
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)
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def send_cannot_create_directory_alias_disabled(user, alias_address, directory_name):
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"""when the directory is disabled, new alias can't be created on-the-fly.
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Send user an email to notify of an attempt
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"""
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send_email_with_rate_control(
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user,
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ALERT_DIRECTORY_DISABLED_ALIAS_CREATION,
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user.email,
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f"Alias {alias_address} cannot be created",
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render(
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"transactional/cannot-create-alias-directory-disabled.txt",
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name=user.name,
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alias=alias_address,
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directory=directory_name,
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),
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render(
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"transactional/cannot-create-alias-directory-disabled.html",
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name=user.name,
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alias=alias_address,
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directory=directory_name,
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),
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)
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def send_cannot_create_domain_alias(user, alias, domain):
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"""when user cancels their subscription, they cannot create alias on the fly with custom domain.
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If this happens, send them an email to notify
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"""
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send_email(
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user.email,
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f"Alias {alias} cannot be created",
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render(
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"transactional/cannot-create-alias-domain.txt",
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name=user.name,
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alias=alias,
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domain=domain,
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),
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render(
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"transactional/cannot-create-alias-domain.html",
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name=user.name,
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alias=alias,
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domain=domain,
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),
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)
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def send_email(
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to_email,
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subject,
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plaintext,
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html=None,
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unsubscribe_link=None,
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unsubscribe_via_email=False,
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):
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if NOT_SEND_EMAIL:
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LOG.d(
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"send email with subject '%s' to '%s', plaintext: %s",
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subject,
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to_email,
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plaintext,
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)
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return
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LOG.d("send email to %s, subject %s", to_email, subject)
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if POSTFIX_SUBMISSION_TLS:
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smtp = SMTP(POSTFIX_SERVER, 587)
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smtp.starttls()
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else:
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smtp = SMTP(POSTFIX_SERVER, POSTFIX_PORT or 25)
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msg = MIMEMultipart("alternative")
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msg.attach(MIMEText(plaintext, "text"))
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if not html:
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LOG.d("Use plaintext as html")
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html = plaintext.replace("\n", "<br>")
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msg.attach(MIMEText(html, "html"))
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msg["Subject"] = subject
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msg["From"] = f"{SUPPORT_NAME} <{SUPPORT_EMAIL}>"
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msg["To"] = to_email
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msg_id_header = make_msgid()
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msg["Message-ID"] = msg_id_header
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date_header = formatdate()
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msg["Date"] = date_header
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if unsubscribe_link:
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add_or_replace_header(msg, "List-Unsubscribe", f"<{unsubscribe_link}>")
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if not unsubscribe_via_email:
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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
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email_domain = SUPPORT_EMAIL[SUPPORT_EMAIL.find("@") + 1 :]
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add_dkim_signature(msg, email_domain)
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msg_raw = to_bytes(msg)
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if SENDER:
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smtp.sendmail(SENDER, to_email, msg_raw)
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else:
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smtp.sendmail(SUPPORT_EMAIL, to_email, msg_raw)
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def send_email_with_rate_control(
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user: User,
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alert_type: str,
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to_email: str,
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subject,
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plaintext,
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html=None,
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max_nb_alert=MAX_ALERT_24H,
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nb_day=1,
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) -> bool:
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"""Same as send_email with rate control over alert_type.
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Make sure no more than `max_nb_alert` emails are sent over the period of `nb_day` days
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Return true if the email is sent, otherwise False
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"""
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to_email = to_email.lower().strip()
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min_dt = arrow.now().shift(days=-1 * nb_day)
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nb_alert = (
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SentAlert.query.filter_by(alert_type=alert_type, to_email=to_email)
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.filter(SentAlert.created_at > min_dt)
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.count()
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)
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if nb_alert >= max_nb_alert:
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LOG.warning(
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"%s emails were sent to %s in the last %s days, alert type %s",
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nb_alert,
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to_email,
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nb_day,
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alert_type,
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)
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return False
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SentAlert.create(user_id=user.id, alert_type=alert_type, to_email=to_email)
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db.session.commit()
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send_email(to_email, subject, plaintext, html)
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return True
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def send_email_at_most_times(
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user: User,
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alert_type: str,
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to_email: str,
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subject,
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plaintext,
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html=None,
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max_times=1,
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) -> bool:
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"""Same as send_email with rate control over alert_type.
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Sent at most `max_times`
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This is used to inform users about a warning.
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Return true if the email is sent, otherwise False
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"""
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to_email = to_email.lower().strip()
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nb_alert = SentAlert.query.filter_by(
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alert_type=alert_type, to_email=to_email
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).count()
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if nb_alert >= max_times:
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LOG.warning(
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"%s emails were sent to %s alert type %s",
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nb_alert,
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to_email,
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alert_type,
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)
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return False
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SentAlert.create(user_id=user.id, alert_type=alert_type, to_email=to_email)
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db.session.commit()
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send_email(to_email, subject, plaintext, html)
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return True
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def get_email_local_part(address):
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"""
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Get the local part from email
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ab@cd.com -> ab
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"""
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return address[: address.find("@")]
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def get_email_domain_part(address):
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"""
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Get the domain part from email
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ab@cd.com -> cd.com
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"""
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return address[address.find("@") + 1 :].strip().lower()
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def add_dkim_signature(msg: Message, email_domain: str):
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delete_header(msg, "DKIM-Signature")
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# Specify headers in "byte" form
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# Generate message signature
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sig = dkim.sign(
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to_bytes(msg),
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DKIM_SELECTOR,
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email_domain.encode(),
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DKIM_PRIVATE_KEY.encode(),
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include_headers=DKIM_HEADERS,
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)
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sig = sig.decode()
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# remove linebreaks from sig
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sig = sig.replace("\n", " ").replace("\r", "")
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msg["DKIM-Signature"] = sig[len("DKIM-Signature: ") :]
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def add_or_replace_header(msg: Message, header: str, value: str):
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"""
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Remove all occurrences of `header` and add `header` with `value`.
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"""
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delete_header(msg, header)
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msg[header] = value
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def delete_header(msg: Message, header: str):
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"""a header can appear several times in message."""
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# inspired from https://stackoverflow.com/a/47903323/1428034
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for i in reversed(range(len(msg._headers))):
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header_name = msg._headers[i][0].lower()
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if header_name == header.lower():
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del msg._headers[i]
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def delete_all_headers_except(msg: Message, headers: [str]):
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headers = [h.lower() for h in headers]
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for i in reversed(range(len(msg._headers))):
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header_name = msg._headers[i][0].lower()
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if header_name not in headers:
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del msg._headers[i]
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def can_create_directory_for_address(address: str) -> bool:
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"""return True if an email ends with one of the alias domains provided by SimpleLogin"""
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# not allow creating directory with premium domain
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for domain in ALIAS_DOMAINS:
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if address.endswith("@" + domain):
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return True
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return False
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def is_valid_alias_address_domain(address) -> bool:
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"""Return whether an address domain might a domain handled by SimpleLogin"""
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domain = get_email_domain_part(address)
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if SLDomain.get_by(domain=domain):
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return True
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if CustomDomain.get_by(domain=domain, verified=True):
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return True
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return False
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def email_can_be_used_as_mailbox(email: str) -> bool:
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"""Return True if an email can be used as a personal email.
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Use the email domain as criteria. A domain can be used if it is not:
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- one of ALIAS_DOMAINS
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- one of PREMIUM_ALIAS_DOMAINS
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- one of custom domains
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- a disposable domain
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"""
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domain = get_email_domain_part(email)
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if not domain:
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return False
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if SLDomain.get_by(domain=domain):
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return False
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from app.models import CustomDomain
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if CustomDomain.get_by(domain=domain, verified=True):
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LOG.d("domain %s is a SimpleLogin custom domain", domain)
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return False
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if is_disposable_domain(domain):
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LOG.d("Domain %s is disposable", domain)
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return False
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# check if email MX domain is disposable
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mx_domains = get_mx_domain_list(domain)
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# if no MX record, email is not valid
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if not mx_domains:
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LOG.d("No MX record for domain %s", domain)
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return False
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for mx_domain in mx_domains:
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if is_disposable_domain(mx_domain):
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LOG.d("MX Domain %s %s is disposable", mx_domain, domain)
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return False
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return True
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def is_disposable_domain(domain):
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for d in DISPOSABLE_EMAIL_DOMAINS:
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if domain == d:
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return True
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# subdomain
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if domain.endswith("." + d):
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return True
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return False
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def get_mx_domain_list(domain) -> [str]:
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"""return list of MX domains for a given email.
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domain name ends *without* a dot (".") at the end.
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"""
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priority_domains = get_mx_domains(domain)
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return [d[:-1] for _, d in priority_domains]
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|
|
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def personal_email_already_used(email: str) -> bool:
|
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"""test if an email can be used as user email"""
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if User.get_by(email=email):
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return True
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return False
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|
|
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def mailbox_already_used(email: str, user) -> bool:
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if Mailbox.get_by(email=email, user_id=user.id):
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return True
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# support the case user wants to re-add their real email as mailbox
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# can happen when user changes their root email and wants to add this new email as mailbox
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if email == user.email:
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return False
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return False
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|
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def get_orig_message_from_bounce(msg: Message) -> Message:
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"""parse the original email from Bounce"""
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i = 0
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for part in msg.walk():
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i += 1
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# the original message is the 4th part
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# 1st part is the root part, multipart/report
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# 2nd is text/plain, Postfix log
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# ...
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# 7th is original message
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if i == 7:
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return part
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|
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def get_header_from_bounce(msg: Message, header: str) -> str:
|
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"""using regex to get header value from bounce message
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get_orig_message_from_bounce is better. This should be the last option
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"""
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msg_str = str(msg)
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exp = re.compile(f"{header}.*\n")
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r = re.search(exp, msg_str)
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if r:
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# substr should be something like 'HEADER: 1234'
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substr = msg_str[r.start() : r.end()].strip()
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parts = substr.split(":")
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return parts[1].strip()
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return None
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|
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def get_orig_message_from_spamassassin_report(msg: Message) -> Message:
|
|
"""parse the original email from Spamassassin report"""
|
|
i = 0
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for part in msg.walk():
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i += 1
|
|
|
|
# the original message is the 4th part
|
|
# 1st part is the root part, multipart/report
|
|
# 2nd is text/plain, SpamAssassin part
|
|
# 3rd is the original message in message/rfc822 content type
|
|
# 4th is original message
|
|
if i == 4:
|
|
return part
|
|
|
|
|
|
def get_spam_info(msg: Message, max_score=None) -> (bool, str):
|
|
"""parse SpamAssassin header to detect whether a message is classified as spam.
|
|
Return (is spam, spam status detail)
|
|
The header format is
|
|
```X-Spam-Status: No, score=-0.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID,
|
|
DKIM_VALID_AU,RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H2,SPF_PASS,
|
|
URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.2```
|
|
"""
|
|
spamassassin_status = msg["X-Spam-Status"]
|
|
if not spamassassin_status:
|
|
return False, ""
|
|
|
|
return get_spam_from_header(spamassassin_status, max_score=max_score)
|
|
|
|
|
|
def get_spam_from_header(spam_status_header, max_score=None) -> (bool, str):
|
|
"""get spam info from X-Spam-Status header
|
|
Return (is spam, spam status detail).
|
|
The spam_status_header has the following format
|
|
```No, score=-0.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID,
|
|
DKIM_VALID_AU,RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H2,SPF_PASS,
|
|
URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.2```
|
|
"""
|
|
# yes or no
|
|
spamassassin_answer = spam_status_header[: spam_status_header.find(",")]
|
|
|
|
if max_score:
|
|
# spam score
|
|
# get the score section "score=-0.1"
|
|
score_section = (
|
|
spam_status_header[spam_status_header.find(",") + 1 :].strip().split(" ")[0]
|
|
)
|
|
score = float(score_section[len("score=") :])
|
|
if score >= max_score:
|
|
LOG.warning("Spam score %s exceeds %s", score, max_score)
|
|
return True, spam_status_header
|
|
|
|
return spamassassin_answer.lower() == "yes", spam_status_header
|
|
|
|
|
|
def get_header_unicode(header: str):
|
|
decoded_string, charset = decode_header(header)[0]
|
|
if charset is not None:
|
|
try:
|
|
return decoded_string.decode(charset)
|
|
except UnicodeDecodeError:
|
|
LOG.warning("Cannot decode header %s", header)
|
|
except LookupError: # charset is unknown
|
|
LOG.warning("Cannot decode %s with %s, use utf-8", decoded_string, charset)
|
|
return decoded_string.decode("utf-8")
|
|
|
|
return header
|
|
|
|
|
|
def parseaddr_unicode(addr) -> (str, str):
|
|
"""Like parseaddr() but return name in unicode instead of in RFC 2047 format
|
|
Should be used instead of parseaddr()
|
|
'=?UTF-8?B?TmjGoW4gTmd1eeG7hW4=?= <abcd@gmail.com>' -> ('Nhơn Nguyễn', "abcd@gmail.com")
|
|
"""
|
|
# sometimes linebreaks are present in addr
|
|
addr = addr.replace("\n", "").strip()
|
|
name, email = parseaddr(addr)
|
|
# email can have whitespace so we can't remove whitespace here
|
|
email = email.strip().lower()
|
|
if name:
|
|
name = name.strip()
|
|
decoded_string, charset = decode_header(name)[0]
|
|
if charset is not None:
|
|
try:
|
|
name = decoded_string.decode(charset)
|
|
except UnicodeDecodeError:
|
|
LOG.warning("Cannot decode addr name %s", name)
|
|
name = ""
|
|
except LookupError: # charset is unknown
|
|
LOG.warning(
|
|
"Cannot decode %s with %s, use utf-8", decoded_string, charset
|
|
)
|
|
name = decoded_string.decode("utf-8")
|
|
else:
|
|
name = decoded_string
|
|
|
|
if type(name) == bytes:
|
|
name = name.decode()
|
|
return name, email
|
|
|
|
|
|
def copy(msg: Message) -> Message:
|
|
"""return a copy of message"""
|
|
try:
|
|
# prefer the unicode way
|
|
return email.message_from_string(msg.as_string())
|
|
except (UnicodeEncodeError, KeyError, LookupError):
|
|
LOG.warning("as_string() fails, try to_bytes")
|
|
return email.message_from_bytes(to_bytes(msg))
|
|
|
|
|
|
def to_bytes(msg: Message):
|
|
"""replace Message.as_bytes() method by trying different policies"""
|
|
try:
|
|
return msg.as_bytes()
|
|
except UnicodeEncodeError:
|
|
LOG.warning("as_bytes fails with default policy, try SMTP policy")
|
|
try:
|
|
return msg.as_bytes(policy=email.policy.SMTP)
|
|
except UnicodeEncodeError:
|
|
LOG.warning("as_bytes fails with SMTP policy, try SMTPUTF8 policy")
|
|
try:
|
|
return msg.as_bytes(policy=email.policy.SMTPUTF8)
|
|
except UnicodeEncodeError:
|
|
LOG.warning(
|
|
"as_bytes fails with SMTPUTF8 policy, try converting to string"
|
|
)
|
|
return msg.as_string().encode()
|
|
|
|
|
|
def should_add_dkim_signature(domain: str) -> bool:
|
|
if SLDomain.get_by(domain=domain):
|
|
return True
|
|
|
|
custom_domain: CustomDomain = CustomDomain.get_by(domain=domain)
|
|
if custom_domain.dkim_verified:
|
|
return True
|
|
|
|
return False
|
|
|
|
|
|
def is_valid_email(email_address: str) -> bool:
|
|
"""Used to check whether an email address is valid"""
|
|
return validate_email(
|
|
email_address=email_address, check_mx=False, use_blacklist=False
|
|
)
|
|
|
|
|
|
class EmailEncoding(enum.Enum):
|
|
BASE64 = "base64"
|
|
QUOTED = "quoted-printable"
|
|
NO = "no-encoding"
|
|
|
|
|
|
def get_encoding(msg: Message) -> EmailEncoding:
|
|
"""
|
|
Return the message encoding, possible values:
|
|
- quoted-printable
|
|
- base64
|
|
- 7bit: default if unknown or empty
|
|
"""
|
|
cte = str(msg.get("content-transfer-encoding", "")).lower()
|
|
if cte in ("", "7bit", "8bit", "binary"):
|
|
return EmailEncoding.NO
|
|
|
|
if cte == "base64":
|
|
return EmailEncoding.BASE64
|
|
|
|
if cte == "quoted-printable":
|
|
return EmailEncoding.QUOTED
|
|
|
|
LOG.exception("Unknown encoding %s", cte)
|
|
|
|
return EmailEncoding.NO
|
|
|
|
|
|
def encode_text(text: str, encoding: EmailEncoding = EmailEncoding.NO) -> str:
|
|
if encoding == EmailEncoding.QUOTED:
|
|
encoded = quopri.encodestring(text.encode("utf-8"))
|
|
return str(encoded, "utf-8")
|
|
elif encoding == EmailEncoding.BASE64:
|
|
encoded = base64.b64encode(text.encode("utf-8"))
|
|
return str(encoded, "utf-8")
|
|
else: # 7bit - no encoding
|
|
return text
|
|
|
|
|
|
def decode_text(text: str, encoding: EmailEncoding = EmailEncoding.NO) -> str:
|
|
if encoding == EmailEncoding.QUOTED:
|
|
decoded = quopri.decodestring(text.encode("utf-8"))
|
|
return decoded.decode(errors="ignore")
|
|
elif encoding == EmailEncoding.BASE64:
|
|
decoded = base64.b64decode(text.encode("utf-8"))
|
|
return decoded.decode(errors="ignore")
|
|
else: # 7bit - no encoding
|
|
return text
|
|
|
|
|
|
def add_header(msg: Message, text_header, html_header) -> Message:
|
|
if msg.get_content_type() == "text/plain":
|
|
encoding = get_encoding(msg)
|
|
payload = msg.get_payload()
|
|
if type(payload) is str:
|
|
clone_msg = copy(msg)
|
|
new_payload = f"""{text_header}
|
|
---
|
|
{decode_text(payload, encoding)}"""
|
|
clone_msg.set_payload(encode_text(new_payload, encoding))
|
|
return clone_msg
|
|
elif msg.get_content_type() == "text/html":
|
|
encoding = get_encoding(msg)
|
|
payload = msg.get_payload()
|
|
if type(payload) is str:
|
|
new_payload = f"""<table width="100%" style="width: 100%; -premailer-width: 100%; -premailer-cellpadding: 0;
|
|
-premailer-cellspacing: 0; margin: 0; padding: 0;">
|
|
<tr>
|
|
<td style="border-bottom:1px dashed #5675E2; padding: 10px 0px">{html_header}</td>
|
|
</tr>
|
|
<tr>
|
|
<td>
|
|
{decode_text(payload, encoding)}
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
"""
|
|
|
|
clone_msg = copy(msg)
|
|
clone_msg.set_payload(encode_text(new_payload, encoding))
|
|
return clone_msg
|
|
elif msg.get_content_type() in ("multipart/alternative", "multipart/related"):
|
|
new_parts = []
|
|
for part in msg.get_payload():
|
|
new_parts.append(add_header(part, text_header, html_header))
|
|
clone_msg = copy(msg)
|
|
clone_msg.set_payload(new_parts)
|
|
return clone_msg
|
|
|
|
LOG.d("No header added for %s", msg.get_content_type())
|
|
return msg
|
|
|
|
|
|
def replace(msg: Message, old, new) -> Message:
|
|
content_type = msg.get_content_type()
|
|
|
|
if (
|
|
content_type.startswith("image/")
|
|
or content_type.startswith("video/")
|
|
or content_type.startswith("audio/")
|
|
or content_type == "multipart/signed"
|
|
or content_type.startswith("application/")
|
|
or content_type == "text/calendar"
|
|
or content_type == "text/directory"
|
|
):
|
|
LOG.d("not applicable for %s", content_type)
|
|
return msg
|
|
|
|
if content_type in ("text/plain", "text/html"):
|
|
encoding = get_encoding(msg)
|
|
payload = msg.get_payload()
|
|
if type(payload) is str:
|
|
clone_msg = copy(msg)
|
|
new_payload = payload.replace(
|
|
encode_text(old, encoding), encode_text(new, encoding)
|
|
)
|
|
clone_msg.set_payload(new_payload)
|
|
return clone_msg
|
|
|
|
elif content_type in (
|
|
"multipart/alternative",
|
|
"multipart/related",
|
|
"multipart/mixed",
|
|
):
|
|
new_parts = []
|
|
for part in msg.get_payload():
|
|
new_parts.append(replace(part, old, new))
|
|
clone_msg = copy(msg)
|
|
clone_msg.set_payload(new_parts)
|
|
return clone_msg
|
|
|
|
LOG.exception("Cannot replace text for %s", msg.get_content_type())
|
|
return msg
|
|
|
|
|
|
def generate_reply_email(contact_email: str, user: User) -> str:
|
|
"""
|
|
generate a reply_email (aka reverse-alias), make sure it isn't used by any contact
|
|
"""
|
|
# shorten email to avoid exceeding the 64 characters
|
|
# from https://tools.ietf.org/html/rfc5321#section-4.5.3
|
|
# "The maximum total length of a user name or other local-part is 64
|
|
# octets."
|
|
|
|
include_sender_in_reverse_alias = False
|
|
|
|
# user has chosen an option explicitly
|
|
if user.include_sender_in_reverse_alias is not None:
|
|
include_sender_in_reverse_alias = user.include_sender_in_reverse_alias
|
|
|
|
if include_sender_in_reverse_alias and contact_email:
|
|
# control char: 4 chars (ra+, +)
|
|
# random suffix: max 10 chars
|
|
# maximum: 64
|
|
|
|
# make sure contact_email can be ascii-encoded
|
|
contact_email = convert_to_id(contact_email)
|
|
contact_email = contact_email.lower().strip().replace(" ", "")
|
|
contact_email = contact_email[:45]
|
|
contact_email = contact_email.replace("@", ".at.")
|
|
contact_email = convert_to_alphanumeric(contact_email)
|
|
|
|
# not use while to avoid infinite loop
|
|
for _ in range(1000):
|
|
if include_sender_in_reverse_alias and contact_email:
|
|
random_length = random.randint(5, 10)
|
|
reply_email = (
|
|
f"ra+{contact_email}+{random_string(random_length)}@{EMAIL_DOMAIN}"
|
|
)
|
|
else:
|
|
random_length = random.randint(20, 50)
|
|
reply_email = f"ra+{random_string(random_length)}@{EMAIL_DOMAIN}"
|
|
|
|
if not Contact.get_by(reply_email=reply_email):
|
|
return reply_email
|
|
|
|
raise Exception("Cannot generate reply email")
|
|
|
|
|
|
def is_reply_email(address: str) -> bool:
|
|
return address.startswith("reply+") or address.startswith("ra+")
|
|
|
|
|
|
# allow also + and @ that are present in a reply address
|
|
_ALLOWED_CHARS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_-.+@"
|
|
|
|
|
|
def normalize_reply_email(reply_email: str) -> str:
|
|
"""Handle the case where reply email contains *strange* char that was wrongly generated in the past"""
|
|
if not reply_email.isascii():
|
|
reply_email = convert_to_id(reply_email)
|
|
|
|
ret = []
|
|
# drop all control characters like shift, separator, etc
|
|
for c in reply_email:
|
|
if c not in _ALLOWED_CHARS:
|
|
ret.append("_")
|
|
else:
|
|
ret.append(c)
|
|
|
|
return "".join(ret)
|
|
|
|
|
|
def should_disable(alias: Alias) -> bool:
|
|
"""Disable an alias if it has more than 5 bounces in the last 24h"""
|
|
yesterday = arrow.now().shift(days=-1)
|
|
nb_bounced_last_24h = (
|
|
db.session.query(EmailLog)
|
|
.join(Contact, EmailLog.contact_id == Contact.id)
|
|
.filter(
|
|
EmailLog.bounced.is_(True),
|
|
EmailLog.is_reply.is_(False),
|
|
EmailLog.created_at > yesterday,
|
|
)
|
|
.filter(Contact.alias_id == alias.id)
|
|
.count()
|
|
)
|
|
if nb_bounced_last_24h > 5:
|
|
return True
|
|
return False
|