www: point link to e2ee FAQ from staging to production

Co-authored-by: Hocuri <hocuri@gmx.de>

.github/workflows/ci.yaml

@@ -0,0 +1,31 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+
+jobs:
+  tox:
+    name: chatmail tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: run chatmaild tests 
+        working-directory: chatmaild
+        run: pipx run tox
+      - name: run deploy-chatmail offline tests 
+        working-directory: deploy-chatmail
+        run: pipx run tox
+      - name: run deploy-chatmail offline tests 
+        working-directory: deploy-chatmail
+        run: pipx run tox
+
+  scripts:
+    name: chatmail script invocations 
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: run init.sh 
+        run: ./scripts/init.sh 
+      - name: run test.sh 
+        run: ./scripts/test.sh 

.gitignore

@@ -10,7 +10,6 @@ __pycache__/
 # Distribution / packaging
 .Python
 build/
-doveauth/dist/
 develop-eggs/
 dist/
 downloads/
@@ -160,3 +159,5 @@ cython_debug/
 #  and can be added to the global gitignore or merged into this file.  For a more nuclear
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
 #.idea/
+
+chatmail.zone

README.md

@@ -1,65 +1,96 @@
-# Chat Mail server configuration
+# Chatmail instances optimized for Delta Chat apps 
 
-This package deploys Postfix and Dovecot servers, including OpenDKIM for DKIM signing.
+This repository helps to setup a ready-to-use chatmail instance
+comprised of a minimal setup of the battle-tested 
+[postfix smtp](https://www.postfix.org) and [dovecot imap](https://www.dovecot.org) services. 
 
-Postfix uses Dovecot for authentication as described in <https://www.postfix.org/SASL_README.html#server_dovecot>
+The setup is designed and optimized for providing chatmail accounts 
+for use by [Delta Chat apps](https://delta.chat).
 
-## Getting started 
+Chatmail accounts are automatically created by a first login, 
+after which the initially specified password is required for using them. 
 
-prepare:
+## Getting Started deploying your own chatmail instance
 
-    pip install -e chatmail-infra
+1. Prepare your local (presumably Linux) system:
 
+    scripts/init.sh 
 
-then run with pyinfra command line tool: 
+2. Setup a domain with `A` and `AAAA` records for your chatmail server.
 
-    CHATMAIL_DOMAIN=c1.testrun.org pyinfra --ssh-user root c1.testrun.org deploy.py
+3. Set environment variable to the chatmail domain you want to setup:
 
+    export CHATMAIL_DOMAIN=c1.testrun.org   # replace with your host
 
-## Structure (wip)
-```
+4. Deploy the chat mail instance to your chatmail server: 
 
-# package doveauth tool and deploy chatmail server to a envvar-specified ssh-reachable host 
-deploy.py 
+    scripts/deploy.sh 
 
-# chatmail pyinfra deploy package 
-chatmail-pyinfra 
-    pyproject.toml
-    chatmail/__init__ ...
+   This script uses `pyinfra` and `ssh` to setup packages and configure
+   the chatmail instance on your remote server. 
 
-    # tests against the deployed system 
-    tests/test_online_test.py
+5. Run `scripts/generate-dns-zone.sh` and 
+   transfer the generated DNS records at your DNS provider
 
-# doveauth tool used by dovecot's auth mechanism on the host system 
-doveauth
-    README.md
-    pyproject.toml
-    doveauth.py
-    doveauth.lua
-    test_doveauth.py
+6. Start a Delta Chat app and create a new account 
+   by typing an e-mail address with an arbitrary username 
+   and `@<your-chatmail-domain>` appended. 
+   Use an at least 10-character random password. 
 
-# lmtp server to block (outgoing) unencrypted messages 
-filtermail 
-    README.md
-    pyproject.toml
-    .... 
-
-
-# scripts for setup/development/deployment 
-
-scripts/
-    init.sh  # create venv/other perequires
-    deploy.sh  # run pyinfra based deploy of everything
-
-```
-
-## Dovecot/Postfix configuration
 
 ### Ports
 
 Postfix listens on ports 25 (smtp) and 587 (submission) and 465 (submissions).
 Dovecot listens on ports 143(imap) and 993 (imaps).
 
-## DNS
+Delta Chat will, however, discover all ports and configurations 
+automatically by reading the `autoconfig.xml` file from the chatmail instance. 
+
+
+## Emergency Commands to disable automatic account creation 
+
+If you need to stop account creation,
+e.g. because some script is wildly creating accounts, run:
+
+    touch /etc/chatmail-nocreate
+
+While this file is present, account creation will be blocked. 
+
+
+## Running tests and benchmarks (offline and online) 
+
+1. Set `CHATMAIL_SSH` so that `ssh root@$CHATMAIL_SSH` allows 
+   to login to the chatmail instance server. 
+
+2. To run local and online tests: 
+
+    scripts/test.sh 
+
+3. To run benchmarks against your chatmail instance: 
+
+    scripts/bench.sh 
+
+
+## Development Background for chatmail instances 
+
+This repository drives the development of "chatmail instances", 
+comprised of minimal setups of 
+
+- [postfix smtp server](https://www.postfix.org) 
+- [dovecot imap server](https://www.dovecot.org) 
+
+as well as two custom services that are integrated with these two: 
+
+- `chatmaild/src/chatmaild/doveauth.py` implements
+  create-on-login account creation semantics and is used
+  by Dovecot during login authentication and by Postfix
+  which in turn uses [Dovecot SASL](https://doc.dovecot.org/configuration_manual/authentication/dict/#complete-example-for-authenticating-via-a-unix-socket)
+  to authenticate users
+  to send mails for them. 
+
+- `chatmaild/src/chatmaild/filtermail.py` prevents 
+  unencrypted e-mail from leaving the chatmail instance
+  and is integrated into postfix's outbound mail pipelines. 
+
+
 
-For DKIM you must add a DNS entry as in /etc/opendkim/selector.txt (where selector is the opendkim_selector configured in the chatmail inventory).

chatmail-pyinfra/src/chatmail/__init__.py

@@ -1,213 +0,0 @@
-"""
-Chat Mail pyinfra deploy.
-"""
-import importlib.resources
-from pathlib import Path
-
-from pyinfra import host, logger
-from pyinfra.operations import apt, files, server, systemd, python
-from pyinfra.facts.files import File
-from .acmetool import deploy_acmetool
-
-
-def _install_doveauth() -> None:
-    """Setup chatctl."""
-    doveauth_filename = "doveauth-0.1.tar.gz"
-    doveauth_path = importlib.resources.files(__package__).joinpath(
-        f"../../../doveauth/dist/{doveauth_filename}"
-    )
-    remote_path = f"/tmp/{doveauth_filename}"
-    if Path(str(doveauth_path)).exists():
-        files.put(
-            name="upload local doveauth build",
-            src=doveauth_path.open("rb"),
-            dest=remote_path,
-        )
-        apt.packages(
-            name="apt install python3-pip",
-            packages="python3-pip",
-        )
-        # Maybe if we introduce dependencies to the doveauth package at some point, we should not install doveauth
-        # system-wide anymore. For now it's fine though.
-        server.shell(
-            name="install local doveauth build with pip",
-            commands=[f"pip install --break-system-packages {remote_path}"],
-        )
-
-
-def _configure_opendkim(domain: str, dkim_selector: str) -> bool:
-    """Configures OpenDKIM"""
-    need_restart = False
-
-    main_config = files.template(
-        src=importlib.resources.files(__package__).joinpath("opendkim/opendkim.conf"),
-        dest="/etc/opendkim.conf",
-        user="root",
-        group="root",
-        mode="644",
-        config={"domain_name": domain, "opendkim_selector": dkim_selector},
-    )
-
-    files.directory(
-        name="Add opendkim socket directory to /var/spool/postfix",
-        path="/var/spool/postfix/opendkim",
-        user="opendkim",
-        group="opendkim",
-        mode="750",
-        present=True,
-    )
-
-    if not host.get_fact(File, f"/etc/dkimkeys/{dkim_selector}.private"):
-        server.shell(
-            name="Generate OpenDKIM domain keys",
-            commands=[
-                f"opendkim-genkey -D /etc/dkimkeys -d {domain} -s {dkim_selector}"
-            ],
-            _sudo=True,
-            _sudo_user="opendkim",
-        )
-
-    need_restart |= main_config.changed
-
-    return need_restart
-
-
-def _configure_postfix(domain: str) -> bool:
-    """Configures Postfix SMTP server."""
-    need_restart = False
-
-    main_config = files.template(
-        src=importlib.resources.files(__package__).joinpath("postfix/main.cf.j2"),
-        dest="/etc/postfix/main.cf",
-        user="root",
-        group="root",
-        mode="644",
-        config={"domain_name": domain},
-    )
-    need_restart |= main_config.changed
-
-    master_config = files.put(
-        src=importlib.resources.files(__package__)
-        .joinpath("postfix/master.cf")
-        .open("rb"),
-        dest="/etc/postfix/master.cf",
-        user="root",
-        group="root",
-        mode="644",
-    )
-    need_restart |= master_config.changed
-
-    return need_restart
-
-
-def _configure_dovecot(mail_server: str) -> bool:
-    """Configures Dovecot IMAP server."""
-    need_restart = False
-
-    main_config = files.template(
-        src=importlib.resources.files(__package__).joinpath("dovecot/dovecot.conf.j2"),
-        dest="/etc/dovecot/dovecot.conf",
-        user="root",
-        group="root",
-        mode="644",
-        config={"hostname": mail_server},
-    )
-    need_restart |= main_config.changed
-
-    # luarocks install http lpeg_patterns fifo
-    auth_script = files.put(
-        src=importlib.resources.files("doveauth").joinpath("doveauth.lua"),
-        dest="/etc/dovecot/doveauth.lua",
-        user="root",
-        group="root",
-        mode="644",
-    )
-    need_restart |= auth_script.changed
-
-    return need_restart
-
-
-def deploy_chatmail(mail_domain: str, mail_server: str, dkim_selector: str) -> None:
-    """Deploy a chat-mail instance.
-
-    :param mail_domain: domain part of your future email addresses
-    :param mail_server: the DNS name under which your mail server is reachable
-    :param dkim_selector:
-    """
-
-    apt.update(name="apt update")
-    server.group(name="Create vmail group", group="vmail", system=True)
-    server.user(name="Create vmail user", user="vmail", group="vmail", system=True)
-
-    server.group(name="Create opendkim group", group="opendkim", system=True)
-    server.user(
-        name="Add postfix user to opendkim group for socket access",
-        user="postfix",
-        groups=["opendkim"],
-        system=True,
-    )
-
-    # Deploy acmetool to have TLS certificates.
-    deploy_acmetool(domains=[mail_server])
-
-    apt.packages(
-        name="Install Postfix",
-        packages="postfix",
-    )
-
-    apt.packages(
-        name="Install Dovecot",
-        packages=[
-            "dovecot-imapd",
-            "dovecot-lmtpd",
-            "dovecot-auth-lua",
-        ],
-    )
-
-    apt.packages(
-        name="Install OpenDKIM",
-        packages=[
-            "opendkim",
-            "opendkim-tools",
-        ],
-    )
-
-    _install_doveauth()
-    dovecot_need_restart = _configure_dovecot(mail_server)
-    postfix_need_restart = _configure_postfix(mail_domain)
-    opendkim_need_restart = _configure_opendkim(mail_domain, dkim_selector)
-
-    systemd.service(
-        name="Start and enable OpenDKIM",
-        service="opendkim.service",
-        running=True,
-        enabled=True,
-        restarted=opendkim_need_restart,
-    )
-
-    systemd.service(
-        name="Start and enable Postfix",
-        service="postfix.service",
-        running=True,
-        enabled=True,
-        restarted=postfix_need_restart,
-    )
-
-    systemd.service(
-        name="Start and enable Dovecot",
-        service="dovecot.service",
-        running=True,
-        enabled=True,
-        restarted=dovecot_need_restart,
-    )
-
-    def callback():
-        result = server.shell(
-            commands=[
-                f"""sed 's/\tIN/ 600 IN/;s/\t(//;s/\"$//;s/^\t  \"//g; s/ ).*//' """
-                f"""/etc/dkimkeys/{dkim_selector}.txt | tr --delete '\n'"""
-            ]
-        )
-        logger.info(f"Add this TXT entry into DNS zone: {result.stdout}")
-
-    python.call(name="Print TXT entry for DKIM", function=callback)

chatmail-pyinfra/src/chatmail/acmetool/acmetool-redirector.service

@@ -1,11 +0,0 @@
-[Unit]
-Description=acmetool HTTP redirector
-
-[Service]
-Type=notify
-ExecStart=/usr/bin/acmetool redirector --service.uid=daemon
-Restart=always
-RestartSec=30
-
-[Install]
-WantedBy=multi-user.target

chatmail-pyinfra/tests/test_online_login.py

@@ -1,28 +0,0 @@
-import pytest
-import imaplib
-
-
-@pytest.fixture
-def conn():
-    return connect("c1.testrun.org")
-
-
-def login(conn, user, password):
-    print("trying to login", user, password)
-    conn.login(user, password)
-
-
-def connect(host):
-    print(f"connecting to {host}")
-    conn = imaplib.IMAP4_SSL(host)
-    return conn
-
-
-def test_login_ok(conn):
-    login(conn, "link2xt@c1.testrun.org", "Ahyei6ie")
-
-
-def test_login_fail(conn):
-    with pytest.raises(imaplib.IMAP4.error) as excinfo:
-        login(conn, "link2xt@c1.testrun.org", "qweqwe")
-    assert "AUTHENTICATIONFAILED" in str(excinfo)

chatmaild/README.md

@@ -0,0 +1,5 @@
+# chatmaild
+
+chatmaild provides dovecot autentication
+to create dovecot users on login
+and mail filtering.

chatmaild/pyproject.toml

@@ -3,11 +3,15 @@ requires = ["setuptools>=45"]
 build-backend = "setuptools.build_meta"
 
 [project]
-name = "doveauth"
+name = "chatmaild"
 version = "0.1"
+dependencies = [
+  "aiosmtpd"
+]
 
 [project.scripts]
-doveauth = "doveauth.doveauth:main"
+doveauth = "chatmaild.doveauth:main"
+filtermail = "chatmaild.filtermail:main"
 
 [tool.pytest.ini_options]
 addopts = "-v -ra --strict-markers"
@@ -16,7 +20,7 @@ addopts = "-v -ra --strict-markers"
 legacy_tox_ini = """
 [tox]
 isolated_build = true
-envlist = lint
+envlist = lint,py
 
 [testenv:lint]
 skipdist = True
@@ -27,4 +31,10 @@ deps =
 commands =
   black --quiet --check --diff src/
   ruff src/
+
+[testenv]
+passenv = CHATMAIL_DOMAIN
+deps = pytest 
+       pdbpp 
+commands = pytest -v -rsXx {posargs: ../tests/chatmaild}
 """

chatmaild/src/chatmaild/database.py

@@ -0,0 +1,133 @@
+import sqlite3
+import contextlib
+import time
+from pathlib import Path
+
+
+class DBError(Exception):
+    """error during an operation on the database."""
+
+
+class Connection:
+    def __init__(self, sqlconn, write):
+        self._sqlconn = sqlconn
+        self._write = write
+
+    def close(self):
+        self._sqlconn.close()
+
+    def commit(self):
+        self._sqlconn.commit()
+
+    def rollback(self):
+        self._sqlconn.rollback()
+
+    def execute(self, query, params=()):
+        cur = self.cursor()
+        try:
+            cur.execute(query, params)
+        except sqlite3.IntegrityError as e:
+            raise DBError(e)
+        return cur
+
+    def cursor(self):
+        return self._sqlconn.cursor()
+
+    def get_user(self, addr: str) -> {}:
+        """Get a row from the users table."""
+        q = "SELECT addr, password, last_login from users WHERE addr = ?"
+        row = self._sqlconn.execute(q, (addr,)).fetchone()
+        result = {}
+        if row:
+            result = dict(
+                user=row[0],
+                password=row[1],
+                last_login=row[2],
+            )
+        return result
+
+
+class Database:
+    def __init__(self, path: str):
+        self.path = Path(path)
+        self.ensure_tables()
+
+    def _get_connection(
+        self, write=False, transaction=False, closing=False
+    ) -> Connection:
+        # we let the database serialize all writers at connection time
+        # to play it very safe (we don't have massive amounts of writes).
+        mode = "ro"
+        if write:
+            mode = "rw"
+        if not self.path.exists():
+            mode = "rwc"
+        uri = "file:%s?mode=%s" % (self.path, mode)
+        sqlconn = sqlite3.connect(
+            uri,
+            timeout=60,
+            isolation_level=None if transaction else "DEFERRED",
+            uri=True,
+        )
+
+        # Enable Write-Ahead Logging to avoid readers blocking writers and vice versa.
+        if write:
+            sqlconn.execute("PRAGMA journal_mode=wal")
+
+        if transaction:
+            start_time = time.time()
+            while 1:
+                try:
+                    sqlconn.execute("begin immediate")
+                    break
+                except sqlite3.OperationalError:
+                    # another thread may be writing, give it a chance to finish
+                    time.sleep(0.1)
+                    if time.time() - start_time > 5:
+                        # if it takes this long, something is wrong
+                        raise
+        conn = Connection(sqlconn, write=write)
+        if closing:
+            conn = contextlib.closing(conn)
+        return conn
+
+    @contextlib.contextmanager
+    def write_transaction(self):
+        conn = self._get_connection(closing=False, write=True, transaction=True)
+        try:
+            yield conn
+        except Exception:
+            conn.rollback()
+            conn.close()
+            raise
+        else:
+            conn.commit()
+            conn.close()
+
+    def read_connection(self, closing=True) -> Connection:
+        return self._get_connection(closing=closing, write=False)
+
+    def get_schema_version(self) -> int:
+        with self.read_connection() as conn:
+            dbversion = conn.execute("PRAGMA user_version").fetchone()[0]
+        return dbversion
+
+    CURRENT_DBVERSION = 1
+
+    def ensure_tables(self):
+        with self.write_transaction() as conn:
+            if self.get_schema_version() > 1:
+                raise DBError(
+                    "version is %s; downgrading schema is not supported"
+                    % (self.get_schema_version(),)
+                )
+            conn.execute(
+                """
+                CREATE TABLE IF NOT EXISTS users (
+                    addr TEXT PRIMARY KEY,
+                    password TEXT,
+                    last_login INTEGER
+                )
+            """,
+            )
+            conn.execute("PRAGMA user_version=%s" % (self.CURRENT_DBVERSION,))

chatmaild/src/chatmaild/doveauth.py

@@ -0,0 +1,150 @@
+import logging
+import os
+import time
+import sys
+import json
+import crypt
+from socketserver import (
+    UnixStreamServer,
+    StreamRequestHandler,
+    ThreadingMixIn,
+)
+import pwd
+
+from .database import Database
+
+NOCREATE_FILE = "/etc/chatmail-nocreate"
+
+
+def encrypt_password(password: str):
+    # https://doc.dovecot.org/configuration_manual/authentication/password_schemes/
+    passhash = crypt.crypt(password, crypt.METHOD_SHA512)
+    return "{SHA512-CRYPT}" + passhash
+
+
+def is_allowed_to_create(user, cleartext_password) -> bool:
+    """Return True if user and password are admissable."""
+    if os.path.exists(NOCREATE_FILE):
+        logging.warning(f"blocked account creation because {NOCREATE_FILE!r} exists.")
+        return False
+
+    if len(cleartext_password) < 10:
+        logging.warning("Password needs to be at least 10 characters long")
+        return False
+
+    parts = user.split("@")
+    if len(parts) != 2:
+        logging.warning(f"user {user!r} is not a proper e-mail address")
+        return False
+    localpart, domain = parts
+
+    if domain == "nine.testrun.org":
+        # nine.testrun.org policy, username has to be exactly nine chars
+        if len(localpart) != 9:
+            logging.warning(f"localpart {localpart!r} has not exactly nine chars")
+            return False
+
+    return True
+
+
+def get_user_data(db, user):
+    with db.read_connection() as conn:
+        result = conn.get_user(user)
+    if result:
+        result["uid"] = "vmail"
+        result["gid"] = "vmail"
+    return result
+
+
+def lookup_userdb(db, user):
+    return get_user_data(db, user)
+
+
+def lookup_passdb(db, user, cleartext_password):
+    with db.write_transaction() as conn:
+        userdata = conn.get_user(user)
+        if userdata:
+            # Update last login time.
+            conn.execute(
+                "UPDATE users SET last_login=? WHERE addr=?", (int(time.time()), user)
+            )
+
+            userdata["uid"] = "vmail"
+            userdata["gid"] = "vmail"
+            return userdata
+        if not is_allowed_to_create(user, cleartext_password):
+            return
+
+        encrypted_password = encrypt_password(cleartext_password)
+        q = """INSERT INTO users (addr, password, last_login)
+               VALUES (?, ?, ?)"""
+        conn.execute(q, (user, encrypted_password, int(time.time())))
+        return dict(
+            home=f"/home/vmail/{user}",
+            uid="vmail",
+            gid="vmail",
+            password=encrypted_password,
+        )
+
+
+def handle_dovecot_request(msg, db, mail_domain):
+    short_command = msg[0]
+    if short_command == "L":  # LOOKUP
+        parts = msg[1:].split("\t")
+        keyname, user = parts[:2]
+        namespace, type, *args = keyname.split("/")
+        reply_command = "F"
+        res = ""
+        if namespace == "shared":
+            if type == "userdb":
+                if user.endswith(f"@{mail_domain}"):
+                    res = lookup_userdb(db, user)
+                if res:
+                    reply_command = "O"
+                else:
+                    reply_command = "N"
+            elif type == "passdb":
+                if user.endswith(f"@{mail_domain}"):
+                    res = lookup_passdb(db, user, cleartext_password=args[0])
+                if res:
+                    reply_command = "O"
+                else:
+                    reply_command = "N"
+        json_res = json.dumps(res) if res else ""
+        return f"{reply_command}{json_res}\n"
+    return None
+
+
+class ThreadedUnixStreamServer(ThreadingMixIn, UnixStreamServer):
+    pass
+
+
+def main():
+    socket = sys.argv[1]
+    passwd_entry = pwd.getpwnam(sys.argv[2])
+    db = Database(sys.argv[3])
+    with open("/etc/mailname", "r") as fp:
+        mail_domain = fp.read().strip()
+
+    class Handler(StreamRequestHandler):
+        def handle(self):
+            while True:
+                msg = self.rfile.readline().strip().decode()
+                if not msg:
+                    break
+                res = handle_dovecot_request(msg, db, mail_domain)
+                if res:
+                    self.wfile.write(res.encode("ascii"))
+                    self.wfile.flush()
+
+    try:
+        os.unlink(socket)
+    except FileNotFoundError:
+        pass
+
+    with ThreadedUnixStreamServer(socket, Handler) as server:
+        os.chown(socket, uid=passwd_entry.pw_uid, gid=passwd_entry.pw_gid)
+        try:
+            server.serve_forever()
+        except KeyboardInterrupt:
+            pass

chatmaild/src/chatmaild/doveauth.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Dict authentication proxy for dovecot
+
+[Service]
+ExecStart=/usr/local/bin/doveauth /run/dovecot/doveauth.socket vmail /home/vmail/passdb.sqlite
+Restart=always
+RestartSec=30
+
+[Install]
+WantedBy=multi-user.target

chatmaild/src/chatmaild/filtermail.py

@@ -0,0 +1,157 @@
+#!/usr/bin/env python3
+import asyncio
+import logging
+import time
+import sys
+from email.parser import BytesParser
+from email import policy
+from email.utils import parseaddr
+
+from aiosmtpd.smtp import SMTP
+from aiosmtpd.controller import Controller
+from smtplib import SMTP as SMTPClient
+
+
+def check_encrypted(message):
+    """Check that the message is an OpenPGP-encrypted message."""
+    if not message.is_multipart():
+        return False
+    if message.get("subject") != "...":
+        return False
+    if message.get_content_type() != "multipart/encrypted":
+        return False
+    parts_count = 0
+    for part in message.iter_parts():
+        if parts_count == 0:
+            if part.get_content_type() != "application/pgp-encrypted":
+                return False
+        elif parts_count == 1:
+            if part.get_content_type() != "application/octet-stream":
+                return False
+        else:
+            return False
+        parts_count += 1
+    return True
+
+
+def check_mdn(message, envelope):
+    if len(envelope.rcpt_tos) != 1:
+        return False
+
+    for name in ["auto-submitted", "chat-version"]:
+        if not message.get(name):
+            return False
+
+    if message.get_content_type() != "multipart/report":
+        return False
+
+    body = message.get_body()
+    if body.get_content_type() != "text/plain":
+        return False
+
+    if list(body.iter_attachments()) or list(body.iter_parts()):
+        return False
+
+    # even with all mime-structural checks an attacker
+    # could try to abuse the subject or body to contain links or other
+    # annoyance -- we skip on checking subject/body for now as Delta Chat
+    # should evolve to create E2E-encrypted read receipts anyway.
+    # and then MDNs are just encrypted mail and can pass the border
+    # to other instances.
+
+    return True
+
+
+class SMTPController(Controller):
+    def factory(self):
+        return SMTP(self.handler, **self.SMTP_kwargs)
+
+
+class BeforeQueueHandler:
+    def __init__(self):
+        self.send_rate_limiter = SendRateLimiter()
+
+    async def handle_MAIL(self, server, session, envelope, address, mail_options):
+        logging.info(f"handle_MAIL from {address}")
+        envelope.mail_from = address
+        if not self.send_rate_limiter.is_sending_allowed(address):
+            return f"450 4.7.1: Too much mail from {address}"
+
+        parts = envelope.mail_from.split("@")
+        if len(parts) != 2:
+            return f"500 Invalid from address <{envelope.mail_from!r}>"
+
+        return "250 OK"
+
+    async def handle_DATA(self, server, session, envelope):
+        logging.info("handle_DATA before-queue")
+        error = check_DATA(envelope)
+        if error:
+            return error
+        logging.info("re-injecting the mail that passed checks")
+        client = SMTPClient("localhost", "10025")
+        client.sendmail(envelope.mail_from, envelope.rcpt_tos, envelope.content)
+        return "250 OK"
+
+
+async def asyncmain_beforequeue(port):
+    Controller(BeforeQueueHandler(), hostname="127.0.0.1", port=port).start()
+
+
+def check_DATA(envelope):
+    """the central filtering function for e-mails."""
+    logging.info(f"Processing DATA message from {envelope.mail_from}")
+
+    message = BytesParser(policy=policy.default).parsebytes(envelope.content)
+    mail_encrypted = check_encrypted(message)
+
+    _, from_addr = parseaddr(message.get("from").strip())
+    logging.info(f"mime-from: {from_addr} envelope-from: {envelope.mail_from!r}")
+    if envelope.mail_from.lower() != from_addr.lower():
+        return f"500 Invalid FROM <{from_addr!r}> for <{envelope.mail_from!r}>"
+
+    if not mail_encrypted and check_mdn(message, envelope):
+        return
+
+    envelope_from_domain = from_addr.split("@").pop()
+    for recipient in envelope.rcpt_tos:
+        if envelope.mail_from == recipient:
+            # Always allow sending emails to self.
+            continue
+        res = recipient.split("@")
+        if len(res) != 2:
+            return f"500 Invalid address <{recipient}>"
+        _recipient_addr, recipient_domain = res
+
+        is_outgoing = recipient_domain != envelope_from_domain
+        if is_outgoing and not mail_encrypted:
+            is_securejoin = message.get("secure-join") in ["vc-request", "vg-request"]
+            if not is_securejoin:
+                return f"500 Invalid unencrypted mail to <{recipient}>"
+
+
+class SendRateLimiter:
+    MAX_USER_SEND_PER_MINUTE = 80
+
+    def __init__(self):
+        self.addr2timestamps = {}
+
+    def is_sending_allowed(self, mail_from):
+        last = self.addr2timestamps.setdefault(mail_from, [])
+        now = time.time()
+        last[:] = [ts for ts in last if ts >= (now - 60)]
+        if len(last) <= self.MAX_USER_SEND_PER_MINUTE:
+            last.append(now)
+            return True
+        return False
+
+
+def main():
+    args = sys.argv[1:]
+    assert len(args) == 1
+    logging.basicConfig(level=logging.INFO)
+    loop = asyncio.new_event_loop()
+    asyncio.set_event_loop(loop)
+    task = asyncmain_beforequeue(port=int(args[0]))
+    loop.create_task(task)
+    loop.run_forever()

chatmaild/src/chatmaild/filtermail.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Chatmail Postfix BeforeQeue filter 
+
+[Service]
+ExecStart=/usr/local/bin/filtermail 10080
+Restart=always
+RestartSec=30
+
+[Install]
+WantedBy=multi-user.target

deploy-chatmail/pyproject.toml

@@ -3,7 +3,7 @@ requires = ["setuptools>=45"]
 build-backend = "setuptools.build_meta"
 
 [project]
-name = "chatmail"
+name = "deploy-chatmail"
 version = "0.1"
 dependencies = [
   "pyinfra",

deploy-chatmail/src/deploy_chatmail/__init__.py

@@ -0,0 +1,349 @@
+"""
+Chat Mail pyinfra deploy.
+"""
+import importlib.resources
+from pathlib import Path
+
+from pyinfra import host
+from pyinfra.operations import apt, files, server, systemd
+from pyinfra.facts.files import File
+from pyinfra.facts.systemd import SystemdEnabled
+from .acmetool import deploy_acmetool
+
+
+def _install_chatmaild() -> None:
+    chatmaild_filename = "chatmaild-0.1.tar.gz"
+    chatmaild_path = importlib.resources.files(__package__).joinpath(
+        f"../../../dist/{chatmaild_filename}"
+    )
+    remote_path = f"/tmp/{chatmaild_filename}"
+    if Path(str(chatmaild_path)).exists():
+        files.put(
+            name="Upload chatmaild source package",
+            src=chatmaild_path.open("rb"),
+            dest=remote_path,
+        )
+
+        apt.packages(
+            name="apt install python3-aiosmtpd",
+            packages=["python3-aiosmtpd", "python3-pip"],
+        )
+
+        # --no-deps because aiosmtplib is installed with `apt`.
+        server.shell(
+            name="install chatmaild with pip",
+            commands=[f"pip install --break-system-packages {remote_path}"],
+        )
+
+        # disable legacy doveauth-dictproxy.service
+        if host.get_fact(SystemdEnabled).get("doveauth-dictproxy.service"):
+            systemd.service(
+                name="Disable legacy doveauth-dictproxy.service",
+                service="doveauth-dictproxy.service",
+                running=False,
+                enabled=False,
+            )
+
+        for fn in (
+            "doveauth",
+            "filtermail",
+        ):
+            files.put(
+                name=f"Upload {fn}.service",
+                src=importlib.resources.files("chatmaild")
+                .joinpath(f"{fn}.service")
+                .open("rb"),
+                dest=f"/etc/systemd/system/{fn}.service",
+                user="root",
+                group="root",
+                mode="644",
+            )
+            systemd.service(
+                name=f"Setup {fn} service",
+                service=f"{fn}.service",
+                running=True,
+                enabled=True,
+                restarted=True,
+                daemon_reload=True,
+            )
+
+
+def _configure_opendkim(domain: str, dkim_selector: str) -> bool:
+    """Configures OpenDKIM"""
+    need_restart = False
+
+    main_config = files.template(
+        src=importlib.resources.files(__package__).joinpath("opendkim/opendkim.conf"),
+        dest="/etc/opendkim.conf",
+        user="root",
+        group="root",
+        mode="644",
+        config={"domain_name": domain, "opendkim_selector": dkim_selector},
+    )
+    need_restart |= main_config.changed
+
+    files.directory(
+        name="Add opendkim directory to /etc",
+        path="/etc/opendkim",
+        user="opendkim",
+        group="opendkim",
+        mode="750",
+        present=True,
+    )
+
+    keytable = files.template(
+        src=importlib.resources.files(__package__).joinpath("opendkim/KeyTable"),
+        dest="/etc/dkimkeys/KeyTable",
+        user="opendkim",
+        group="opendkim",
+        mode="644",
+        config={"domain_name": domain, "opendkim_selector": dkim_selector},
+    )
+    need_restart |= keytable.changed
+
+    signing_table = files.template(
+        src=importlib.resources.files(__package__).joinpath("opendkim/SigningTable"),
+        dest="/etc/dkimkeys/SigningTable",
+        user="opendkim",
+        group="opendkim",
+        mode="644",
+        config={"domain_name": domain, "opendkim_selector": dkim_selector},
+    )
+    need_restart |= signing_table.changed
+
+    files.directory(
+        name="Add opendkim socket directory to /var/spool/postfix",
+        path="/var/spool/postfix/opendkim",
+        user="opendkim",
+        group="opendkim",
+        mode="750",
+        present=True,
+    )
+
+    if not host.get_fact(File, f"/etc/dkimkeys/{dkim_selector}.private"):
+        server.shell(
+            name="Generate OpenDKIM domain keys",
+            commands=[
+                f"opendkim-genkey -D /etc/dkimkeys -d {domain} -s {dkim_selector}"
+            ],
+            _sudo=True,
+            _sudo_user="opendkim",
+        )
+
+    return need_restart
+
+
+def _configure_postfix(domain: str, debug: bool = False) -> bool:
+    """Configures Postfix SMTP server."""
+    need_restart = False
+
+    main_config = files.template(
+        src=importlib.resources.files(__package__).joinpath("postfix/main.cf.j2"),
+        dest="/etc/postfix/main.cf",
+        user="root",
+        group="root",
+        mode="644",
+        config={"domain_name": domain},
+    )
+    need_restart |= main_config.changed
+
+    master_config = files.template(
+        src=importlib.resources.files(__package__).joinpath("postfix/master.cf.j2"),
+        dest="/etc/postfix/master.cf",
+        user="root",
+        group="root",
+        mode="644",
+        debug=debug,
+    )
+    need_restart |= master_config.changed
+
+    return need_restart
+
+
+def _configure_dovecot(mail_server: str, debug: bool = False) -> bool:
+    """Configures Dovecot IMAP server."""
+    need_restart = False
+
+    main_config = files.template(
+        src=importlib.resources.files(__package__).joinpath("dovecot/dovecot.conf.j2"),
+        dest="/etc/dovecot/dovecot.conf",
+        user="root",
+        group="root",
+        mode="644",
+        config={"hostname": mail_server},
+        debug=debug,
+    )
+    need_restart |= main_config.changed
+    auth_config = files.put(
+        src=importlib.resources.files(__package__).joinpath("dovecot/auth.conf"),
+        dest="/etc/dovecot/auth.conf",
+        user="root",
+        group="root",
+        mode="644",
+    )
+    need_restart |= auth_config.changed
+
+    files.put(
+        src=importlib.resources.files(__package__)
+        .joinpath("dovecot/expunge.cron")
+        .open("rb"),
+        dest="/etc/cron.d/expunge",
+        user="root",
+        group="root",
+        mode="644",
+    )
+
+    # as per https://doc.dovecot.org/configuration_manual/os/
+    # it is recommended to set the following inotify limits
+    for name in ("max_user_instances", "max_user_watches"):
+        key = f"fs.inotify.{name}"
+        server.sysctl(
+            name=f"Change {key}",
+            key=key,
+            value=65535,
+            persist=True,
+        )
+
+    return need_restart
+
+
+def _configure_nginx(domain: str, debug: bool = False) -> bool:
+    """Configures nginx HTTP server."""
+    need_restart = False
+
+    main_config = files.template(
+        src=importlib.resources.files(__package__).joinpath("nginx/nginx.conf.j2"),
+        dest="/etc/nginx/nginx.conf",
+        user="root",
+        group="root",
+        mode="644",
+        config={"domain_name": domain},
+    )
+    need_restart |= main_config.changed
+
+    autoconfig = files.template(
+        src=importlib.resources.files(__package__).joinpath("nginx/autoconfig.xml.j2"),
+        dest="/var/www/html/.well-known/autoconfig/mail/config-v1.1.xml",
+        user="root",
+        group="root",
+        mode="644",
+        config={"domain_name": domain},
+    )
+    need_restart |= autoconfig.changed
+
+    return need_restart
+
+
+def deploy_chatmail(mail_domain: str, mail_server: str, dkim_selector: str) -> None:
+    """Deploy a chat-mail instance.
+
+    :param mail_domain: domain part of your future email addresses
+    :param mail_server: the DNS name under which your mail server is reachable
+    :param dkim_selector:
+    """
+
+    apt.update(name="apt update", cache_time=24 * 3600)
+    server.group(name="Create vmail group", group="vmail", system=True)
+    server.user(name="Create vmail user", user="vmail", group="vmail", system=True)
+
+    server.group(name="Create opendkim group", group="opendkim", system=True)
+    server.user(
+        name="Add postfix user to opendkim group for socket access",
+        user="postfix",
+        groups=["opendkim"],
+        system=True,
+    )
+
+    # Deploy acmetool to have TLS certificates.
+    deploy_acmetool(nginx_hook=True, domains=[mail_server])
+
+    apt.packages(
+        name="Install Postfix",
+        packages="postfix",
+    )
+
+    apt.packages(
+        name="Install Dovecot",
+        packages=["dovecot-imapd", "dovecot-lmtpd"],
+    )
+
+    apt.packages(
+        name="Install OpenDKIM",
+        packages=[
+            "opendkim",
+            "opendkim-tools",
+        ],
+    )
+
+    apt.packages(
+        name="Install nginx",
+        packages=["nginx"],
+    )
+
+    _install_chatmaild()
+    debug = False
+    dovecot_need_restart = _configure_dovecot(mail_server, debug=debug)
+    postfix_need_restart = _configure_postfix(mail_domain, debug=debug)
+    opendkim_need_restart = _configure_opendkim(mail_domain, dkim_selector)
+    nginx_need_restart = _configure_nginx(mail_domain)
+
+    # deploy web pages and info if we have them
+    pkg_root = importlib.resources.files(__package__)
+    www_path = pkg_root.joinpath(f"../../../www/{mail_domain}").resolve()
+    if www_path.is_dir():
+        files.rsync(f"{www_path}/", "/var/www/html", flags=["-avz"])
+
+    systemd.service(
+        name="Start and enable OpenDKIM",
+        service="opendkim.service",
+        running=True,
+        enabled=True,
+        restarted=opendkim_need_restart,
+    )
+
+    systemd.service(
+        name="Start and enable Postfix",
+        service="postfix.service",
+        running=True,
+        enabled=True,
+        restarted=postfix_need_restart,
+    )
+
+    systemd.service(
+        name="Start and enable Dovecot",
+        service="dovecot.service",
+        running=True,
+        enabled=True,
+        restarted=dovecot_need_restart,
+    )
+
+    systemd.service(
+        name="Start and enable nginx",
+        service="nginx.service",
+        running=True,
+        enabled=True,
+        restarted=nginx_need_restart,
+    )
+
+    # This file is used by auth proxy.
+    # https://wiki.debian.org/EtcMailName
+    server.shell(
+        name="Setup /etc/mailname",
+        commands=[f"echo {mail_domain} >/etc/mailname; chmod 644 /etc/mailname"],
+    )
+
+    journald_conf = files.put(
+        name="Configure journald",
+        src=importlib.resources.files(__package__).joinpath("journald.conf"),
+        dest="/etc/systemd/journald.conf",
+        user="root",
+        group="root",
+        mode="644",
+    )
+    systemd.service(
+        name="Start and enable journald",
+        service="systemd-journald.service",
+        running=True,
+        enabled=True,
+        restarted=journald_conf,
+    )

deploy-chatmail/src/deploy_chatmail/acmetool/__init__.py

@@ -1,6 +1,6 @@
 import importlib.resources
 
-from pyinfra.operations import apt, files, systemd, server
+from pyinfra.operations import apt, files, server
 
 
 def deploy_acmetool(nginx_hook=False, email="", domains=[]):
@@ -38,22 +38,13 @@ def deploy_acmetool(nginx_hook=False, email="", domains=[]):
         email=email,
     )
 
-    service_file = files.put(
-        src=importlib.resources.files(__package__)
-        .joinpath("acmetool-redirector.service")
-        .open("rb"),
-        dest="/etc/systemd/system/acmetool-redirector.service",
+    files.template(
+        src=importlib.resources.files(__package__).joinpath("target.yaml.j2"),
+        dest="/var/lib/acme/conf/target",
         user="root",
         group="root",
         mode="644",
     )
-    systemd.service(
-        name="Setup acmetool-redirector service",
-        service="acmetool-redirector.service",
-        running=True,
-        enabled=True,
-        restarted=service_file.changed,
-    )
 
     for domain in domains:
         server.shell(

deploy-chatmail/src/deploy_chatmail/acmetool/target.yaml.j2

@@ -0,0 +1,7 @@
+request:
+  provider: https://acme-v02.api.letsencrypt.org/directory
+  key:
+    type: rsa
+  challenge:
+    webroot-paths:
+    - /var/www/html/.well-known/acme-challenge

deploy-chatmail/src/deploy_chatmail/deploy.py

@@ -1,12 +1,12 @@
 import os
 import pyinfra
-from chatmail import deploy_chatmail
+from deploy_chatmail import deploy_chatmail
 
 
 def main():
     mail_domain = os.getenv("CHATMAIL_DOMAIN")
     mail_server = os.getenv("CHATMAIL_SERVER", mail_domain)
-    dkim_selector = os.getenv("CHATMAIL_DKIM_SELECTOR", "2023")
+    dkim_selector = os.getenv("CHATMAIL_DKIM_SELECTOR", "dkim")
 
     assert mail_domain
     assert mail_server

deploy-chatmail/src/deploy_chatmail/dovecot/auth.conf

@@ -0,0 +1,5 @@
+uri = proxy:/run/dovecot/doveauth.socket:auth
+iterate_disable = yes
+default_pass_scheme = plain
+password_key = passdb/%w/%u
+user_key = userdb/%u

deploy-chatmail/src/deploy_chatmail/dovecot/dovecot.conf.j2

@@ -4,21 +4,33 @@ protocols = imap lmtp
 
 auth_mechanisms = plain
 
+{% if debug == true %}
 auth_verbose = yes
 auth_debug = yes
 auth_debug_passwords = yes
 auth_verbose_passwords = plain
+auth_cache_size = 100M
+mail_debug = yes
+{% endif %}
+
+
+mail_plugins = quota
+
+# these are the capabilities Delta Chat cares about actually 
+# so let's keep the network overhead per login small
+# https://github.com/deltachat/deltachat-core-rust/blob/master/src/imap/capabilities.rs
+imap_capability = IMAP4rev1 IDLE MOVE QUOTA CONDSTORE NOTIFY
+
 
 # Authentication for system users.
 passdb {
-  driver = lua
-  args = file=/etc/dovecot/doveauth.lua
+  driver = dict
+  args = /etc/dovecot/auth.conf
 }
 userdb {
-  driver = lua
-  args = file=/etc/dovecot/doveauth.lua
+  driver = dict
+  args = /etc/dovecot/auth.conf
 }
-
 ##
 ## Mailbox locations and namespaces
 ##
@@ -60,13 +72,28 @@ mail_privileged_group = vmail
 # Enable IMAP COMPRESS (RFC 4978).
 # <https://datatracker.ietf.org/doc/html/rfc4978.html>
 protocol imap {
-  mail_plugins = $mail_plugins imap_zlib
+  mail_plugins = $mail_plugins imap_zlib imap_quota
+}
+
+protocol lmtp {
+  mail_plugins = $mail_plugins quota
 }
 
 plugin {
   imap_compress_deflate_level = 6
 }
 
+plugin {
+  # for now we define static quota-rules for all users 
+  quota = maildir:User quota
+  quota_rule = *:storage=100M
+  quota_max_mail_size=30M
+  quota_grace = 0
+  # quota_over_flag_value = TRUE
+}
+
+
+
 service lmtp {
   user=vmail
 
@@ -88,7 +115,25 @@ service auth {
 service auth-worker {
   # Default is root.
   # Drop privileges we don't need.
-  user = $default_internal_user
+  user = vmail
+}
+
+service imap-login {
+    # High-security mode.
+    # Each process serves a single connection and exits afterwards.
+    # This is the default, but we set it explicitly to be sure.
+    # See <https://doc.dovecot.org/admin_manual/login_processes/#high-security-mode> for details.
+    service_count = 1
+
+    # Inrease the number of simultaneous connections.
+    #
+    # As of Dovecot 2.3.19.1 the default is 100 processes.
+    # Combined with `service_count = 1` it means only 100 connections
+    # can be handled simultaneously.
+    process_limit = 10000
+
+    # Avoid startup latency for new connections.
+    process_min_avail = 10
 }
 
 ssl = required

deploy-chatmail/src/deploy_chatmail/dovecot/expunge.cron

@@ -0,0 +1,4 @@
+2 0 * * * dovecot doveadm expunge -A SEEN BEFORE 40d INBOX
+2 0 * * * dovecot doveadm expunge -A SEEN BEFORE 40d Deltachat
+2 0 * * * dovecot doveadm expunge -A SEEN BEFORE 40d Trash
+2 30 * * * dovecot doveadm purge -A

deploy-chatmail/src/deploy_chatmail/journald.conf

@@ -0,0 +1,2 @@
+[Journal]
+MaxRetentionSec=3d

deploy-chatmail/src/deploy_chatmail/nginx/autoconfig.xml.j2

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<clientConfig version="1.1">
+  <emailProvider id="{{ config.domain_name }}">
+    <domain>{{ config.domain_name }}</domain>
+    <displayName>{{ config.domain_name }} chatmail</displayName>
+    <displayShortName>{{ config.domain_name }}</displayShortName>
+    <incomingServer type="imap">
+      <hostname>{{ config.domain_name }}</hostname>
+      <port>993</port>
+      <socketType>SSL</socketType>
+      <authentication>password-cleartext</authentication>
+      <username>%EMAILADDRESS%</username>
+    </incomingServer>
+    <incomingServer type="imap">
+      <hostname>{{ config.domain_name }}</hostname>
+      <port>143</port>
+      <socketType>STARTTLS</socketType>
+      <authentication>password-cleartext</authentication>
+      <username>%EMAILADDRESS%</username>
+    </incomingServer>
+    <outgoingServer type="smtp">
+      <hostname>{{ config.domain_name }}</hostname>
+      <port>465</port>
+      <socketType>SSL</socketType>
+      <authentication>password-cleartext</authentication>
+      <username>%EMAILADDRESS%</username>
+    </outgoingServer>
+    <outgoingServer type="smtp">
+      <hostname>{{ config.domain_name }}</hostname>
+      <port>587</port>
+      <socketType>STARTTLS</socketType>
+      <authentication>password-cleartext</authentication>
+      <username>%EMAILADDRESS%</username>
+    </outgoingServer>
+  </emailProvider>
+</clientConfig>

deploy-chatmail/src/deploy_chatmail/nginx/nginx.conf.j2

@@ -0,0 +1,47 @@
+user www-data;
+worker_processes auto;
+pid /run/nginx.pid;
+error_log /var/log/nginx/error.log;
+
+events {
+	worker_connections 768;
+	# multi_accept on;
+}
+
+http {
+	sendfile on;
+	tcp_nopush on;
+
+	# Do not emit nginx version on error pages.
+	server_tokens off;
+
+	include /etc/nginx/mime.types;
+	default_type application/octet-stream;
+
+	ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
+	ssl_prefer_server_ciphers on;
+	ssl_certificate /var/lib/acme/live/{{ config.domain_name }}/fullchain;
+	ssl_certificate_key /var/lib/acme/live/{{ config.domain_name }}/privkey;
+
+	gzip on;
+
+	server {
+		listen 80 default_server;
+		listen [::]:80 default_server;
+		listen 443 ssl default_server;
+		listen [::]:443 ssl default_server;
+
+		root /var/www/html;
+
+		index index.html index.htm;
+
+		server_name _;
+
+		location / {
+			# First attempt to serve request as file, then
+			# as directory, then fall back to displaying a 404.
+			try_files $uri $uri/ =404;
+		}
+	}
+}
+

deploy-chatmail/src/deploy_chatmail/opendkim/KeyTable

@@ -0,0 +1 @@
+dkim._domainkey.{{ config.domain_name }} {{ config.domain_name }}:{{ config.opendkim_selector }}:/etc/dkimkeys/dkim.private

deploy-chatmail/src/deploy_chatmail/opendkim/SigningTable

@@ -0,0 +1 @@
+*@{{ config.domain_name }} {{ config.opendkim_selector }}._domainkey.{{ config.domain_name }}

deploy-chatmail/src/deploy_chatmail/opendkim/opendkim.conf

@@ -1,7 +1,4 @@
-# This is a basic configuration for signing and verifying. It can easily be
-# adapted to suit a basic installation. See opendkim.conf(5) and
-# /usr/share/doc/opendkim/examples/opendkim.conf.sample for complete
-# documentation of available configuration parameters.
+# OpenDKIM configuration.
 
 Syslog			yes
 SyslogSuccess		yes
@@ -21,7 +18,9 @@ OversignHeaders		From
 # setup options can be found in /usr/share/doc/opendkim/README.opendkim.
 Domain			{{ config.domain_name }}
 Selector		{{ config.opendkim_selector }}
-KeyFile		/etc/dkimkeys/{{ config.opendkim_selector }}.private
+KeyFile		  /etc/dkimkeys/{{ config.opendkim_selector }}.private
+KeyTable          /etc/dkimkeys/KeyTable
+SigningTable      /etc/dkimkeys/SigningTable
 
 # In Debian, opendkim runs as user "opendkim". A umask of 007 is required when
 # using a local socket with MTAs that access the socket as a non-privileged

deploy-chatmail/src/deploy_chatmail/postfix/main.cf.j2

@@ -37,6 +37,8 @@ mydestination =
 relayhost = 
 mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
 mailbox_size_limit = 0
+# maximum 30MB sized messages
+message_size_limit = 31457280
 recipient_delimiter = +
 inet_interfaces = all
 inet_protocols = all

deploy-chatmail/src/deploy_chatmail/postfix/master.cf.j2

@@ -9,7 +9,11 @@
 # service type  private unpriv  chroot  wakeup  maxproc command + args
 #               (yes)   (yes)   (no)    (never) (100)
 # ==========================================================================
-smtp      inet  n       -       y       -       -       smtpd
+{% if debug == true %}
+smtp      inet  n       -       y       -       -       smtpd -v
+{% else %}
+smtp      inet  n       -       y       -       -       smtpd 
+{% endif %}
 #smtp      inet  n       -       y       -       1       postscreen
 #smtpd     pass  -       -       y       -       -       smtpd
 #dnsblog   unix  -       -       y       -       0       dnsblog
@@ -28,6 +32,7 @@ submission inet n       -       y       -       -       smtpd
   -o smtpd_recipient_restrictions=
   -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
   -o milter_macro_daemon_name=ORIGINATING
+  -o smtpd_proxy_filter=127.0.0.1:10080
 smtps     inet  n       -       y       -       -       smtpd
   -o syslog_name=postfix/smtps
   -o smtpd_tls_wrappermode=yes
@@ -42,6 +47,7 @@ smtps     inet  n       -       y       -       -       smtpd
   -o smtpd_recipient_restrictions=
   -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
   -o milter_macro_daemon_name=ORIGINATING
+  -o smtpd_proxy_filter=127.0.0.1:10080
 #628       inet  n       -       y       -       -       qmqpd
 pickup    unix  n       -       y       60      1       pickup
 cleanup   unix  n       -       y       -       0       cleanup
@@ -64,9 +70,11 @@ showq     unix  n       -       y       -       -       showq
 error     unix  -       -       y       -       -       error
 retry     unix  -       -       y       -       -       error
 discard   unix  -       -       y       -       -       discard
-local     unix  -       n       n       -       -       local
-virtual   unix  -       n       n       -       -       virtual
 lmtp      unix  -       -       y       -       -       lmtp
 anvil     unix  -       -       y       -       1       anvil
 scache    unix  -       -       y       -       1       scache
 postlog   unix-dgram n  -       n       -       1       postlogd
+filter    unix -        n       n       -       -       lmtp
+# Local SMTP server for reinjecting filered mail.
+localhost:10025 inet  n       -       n       -       10      smtpd
+  -o syslog_name=postfix/reinject

doveauth/README.md

@@ -1,7 +0,0 @@
-# doveauth
-
-doveauth is a python tool
-to create dovecot users on login.
-It is called by the
-[dovecot lua authentication module](https://doc.dovecot.org/configuration_manual/authentication/lua_based_authentication/)
-

doveauth/src/doveauth/doveauth.lua

@@ -1,59 +0,0 @@
-
--- Escape shell argument by hex encoding it and wrapping in quotes.
-function escape(data)
-   b16 = data:gsub(".", function(char) return string.format("%2X", char:byte()) end)
-   return ("'"..b16.."'")
-end
-
--- call out to python program to actually manage authentication for dovecot
-
-function chatctl_verify(user, password)
-    local cmd = "doveauth hexauth "..escape(user).." "..escape(password)
-    print("executing: "..cmd)
-    local handle = io.popen(cmd)
-    local result = handle:read("*a")
-    handle:close()
-    return split_chatctl(result)
-end
-
-function chatctl_lookup(user) 
-    local cmd = "doveauth hexlookup "..escape(user)
-    assert(user)
-    print("executing: "..cmd)
-    local handle = io.popen(cmd)
-    local result = handle:read("*a")
-    handle:close()
-    return split_chatctl(result)
-end
-
-function get_extra_dovecot_output(res)
-    return {home=res.home, uid=res.uid, gid=res.gid}
-end
-
-
-function auth_password_verify(request, password)
-    local res = chatctl_verify(request.user, password)
-    -- request:log_error("auth_password_verify "..request.user.." "..password)
-    if res.status == "ok" then 
-        local extra = get_extra_dovecot_output(res)
-        return dovecot.auth.PASSDB_RESULT_OK, get_extra_dovecot_output(res)
-    end
-    return dovecot.auth.PASSDB_RESULT_PASSWORD_MISMATCH, ""
-end
-
-
-function auth_userdb_lookup(request)
-    local res = chatctl_lookup(request.user) 
-    if res.status == "ok" then
-        return dovecot.auth.USERDB_RESULT_OK, get_extra_dovecot_output(res)
-    end
-    return dovecot.auth.USERDB_RESULT_USER_UNKNOWN, "no such user"
-end
-
-function split_chatctl(output) 
-    local ret = {}
-    for key, value in output:gmatch "(%w+)%s*=%s*(%w+)" do
-        ret[key] = value
-    end
-    return ret
-end

doveauth/src/doveauth/doveauth.py

@@ -1,61 +0,0 @@
-#!/usr/bin/env python3
-import base64
-import sys
-
-
-def get_user_data(user):
-    if user.startswith("link2xt@"):
-        return dict(
-            uid="vmail",
-            gid="vmail",
-            password="Ahyei6ie",
-        )
-    return {}
-
-
-def create_user(user, password):
-    return dict(home=f"/home/vmail/{user}", uid="vmail", gid="vmail", password=password)
-
-
-def verify_user(user, password):
-    userdata = get_user_data(user)
-    if userdata:
-        if userdata.get("password") == password:
-            userdata["status"] = "ok"
-        else:
-            userdata["status"] = "fail"
-    else:
-        userdata = create_user(user, password)
-        userdata["status"] = "ok"
-
-    return userdata
-
-
-def lookup_user(user):
-    userdata = get_user_data(user)
-    if userdata:
-        userdata["status"] = "ok"
-    else:
-        userdata["status"] = "fail"
-    return userdata
-
-
-def dump_result(res):
-    for key, value in res.items():
-        print(f"{key}={value}")
-
-
-def main():
-    if sys.argv[1] == "hexauth":
-        login = base64.b16decode(sys.argv[2]).decode()
-        password = base64.b16decode(sys.argv[3]).decode()
-        res = verify_user(login, password)
-        dump_result(res)
-    elif sys.argv[1] == "hexlookup":
-        login = base64.b16decode(sys.argv[2]).decode()
-        res = lookup_user(login)
-        dump_result(res)
-
-
-if __name__ == "__main__":
-    main()

doveauth/src/doveauth/test_doveauth.lua

@@ -1,78 +0,0 @@
-
-require "doveauth"
-
--- simulate dovecot defined result codes 
-
-dovecot = {
-    auth = {
-        PASSDB_RESULT_OK="PASSWORD-OK",
-        PASSDB_RESULT_PASSWORD_MISMATCH="PASSWORD-MISMATCH",
-        USERDB_RESULT_OK="USERDB-OK",
-        USERDB_RESULT_USER_UNKNOWN="USERDB-UNKNOWN"
-    }
-}
-
-
--- Tests for testing the lua<->python interaction 
-
-function test_password_verify_ok(user, password) 
-    local res, extra = auth_password_verify({user=user}, password)
-    assert(res==dovecot.auth.PASSDB_RESULT_OK)
-    assert(extra.uid == "vmail")
-    assert(extra.gid == "vmail")
-    -- assert(extra.homedir == "/home/vmail/link2xt")
-    print("OK test_password_verify_ok "..user.." "..password)
-end
-
-function test_password_verify_mismatch(user, password) 
-    local res = auth_password_verify({user=user}, password)
-    assert(res == dovecot.auth.PASSDB_RESULT_PASSWORD_MISMATCH)
-    print("OK test_password_verify_mismatch "..user.." "..password)
-end
-
-function test_userdb_lookup_ok(user)
-    local res, extra = auth_userdb_lookup({user=user})
-    assert(extra.uid == "vmail")
-    assert(extra.gid == "vmail")
-    assert(res == dovecot.auth.USERDB_RESULT_OK)
-    print("OK test_userdb_lookup_ok "..user)
-end
-
-function test_userdb_lookup_mismatch(user)
-    local res, extra = auth_userdb_lookup({user=user})
-    assert(res == dovecot.auth.USERDB_RESULT_USER_UNKNOWN)
-    print("OK test_userdb_lookup_mismatch "..user)
-end
-
-function test_passdb_lookup_ok(user)
-    local res, extra = auth_passdb_lookup({user=user})
-    assert(extra.uid == "vmail")
-    assert(extra.gid == "vmail")
-    assert(res == dovecot.auth.PASSDB_RESULT_OK)
-    print("OK test_passdb_lookup_ok "..user)
-end
-
-function test_passdb_lookup_mismatch(user)
-    local res, extra = auth_passdb_lookup({user=user})
-    assert(res == dovecot.auth.PASSDB_RESULT_USER_UNKNOWN)
-    print("OK test_passdb_lookup_mismatch "..user)
-end
-
-function test_split_chatctl()
-    local res = split_chatctl("a=3 b=4\nc=5")
-    assert(res["a"] == "3")
-    assert(res["b"] == "4")
-    assert(res["c"] == "5")
-    print("OK test_split_chatctl")
-end 
-
-test_split_chatctl()
-test_password_verify_ok("link2xt@c1.testrun.org", "Ahyei6ie")
-test_password_verify_mismatch("link2xt@c1.testrun.org", "Aqwlek")
-test_userdb_lookup_ok("link2xt@c1.testrun.org")
-test_userdb_lookup_mismatch("wlekqjlew@xyz.org")
-
--- probably not needed by dovecot? 
--- test_passdb_lookup_ok("link2xt@c1.testrun.org")
--- test_passdb_lookup_mismatch("llqkwjelqwe@xyz.org")
-

doveauth/src/doveauth/test_doveauth.py

@@ -1,23 +0,0 @@
-import subprocess
-import pytest
-
-from doveauth.doveauth import get_user_data, verify_user
-
-
-def test_basic():
-    data = get_user_data("link2xt@c1.testrun.org")
-    assert data
-
-
-@pytest.mark.xfail(reason="no persistence yet")
-def test_verify_or_create():
-    res = verify_user("newuser1@something.org", "kajdlkajsldk12l3kj1983")
-    assert res["status"] == "ok"
-    res = verify_user("newuser1@something.org", "kajdlqweqwe")
-    assert res["status"] == "fail"
-
-
-def test_lua_integration(request):
-    p = request.fspath.dirpath("test_doveauth.lua")
-    proc = subprocess.run(["lua", str(p)])
-    assert proc.returncode == 0

plan.txt

@@ -2,31 +2,58 @@
 
 ## Dovecot goals/steps
 
-1. create-user-on-login ("doveauth")
-  - persistence of accounts
+- automatic expiry of messages older than M days
+   - also expunge unread messages
 
-2. per-user quota (adaptive)
-
-3. automatic expiry of messages older than M days
-
-4. automatic expiry of users that haven't logged in for N days
+- limit: configure max-connections per account
 
 
-## Postfix goals/steps
+## nami: send out rate limit / rspamd
 
-1. block all outgoing mails with our own LMTP program
+- basic outgoing send rate/limits (depending on "account-rating")
+  use rspamd in a minimal way, check support dkim-signing
+  (including an online test exceeding rate limit)
 
-2. only allow (outgoing) mails if secure-join or autocrypt-pgp-encrypted format
-   (probably via an lmtp service)
 
-3. basic outgoing send rate/limits (depending on "account-rating")
+## doveauth questions/futures
+
+- bcrypt-password scheme is slow: require long passwords, use faster hashing
+
+- define user-name and password policies, and implement them
+  (be very restrictive at the beginning, we can relax later)
+
+- password is part of the dictproxy-lookup key, is it safe to use auth-caching?
+
+
+## How to limit creation of accounts?
+
+attack: a 3-line bash script to fill the chatmail db with millions of unused accouts
+
+- make it computationally expensive (somehow try to except our tests from it)
+  1st pass instant onboarding: create userid + cheap password -- if it fails then
+  2nd pass instant onboarding: create userdid + comput. expensive password
+
+- probably also do firewall: limit number of new tcp-connections per IP address per duration
+
+
+## Open/deferred questions
+
+- automatic expiry of users that haven't logged in for N days
+  Is it neccessary?  If all messages are gone, does the existence of
+  an e-mail address bother anybody?
+
+
+## web page for chat-mail servers?
+
+- documentation for users, privacy policy etc.
+  (probably also with provider-messages ...)
 
 
 ## online tests (first with plain python/pytest)
 
 - write tests for dovecot login (exists)
-- write tests for postfix logins
-- write A<>B send/receive tests
+- write tests for postfix logins (exists)
+- write A<>B send/receive tests (exists)
 
 
 ## Delta Chat

scripts/bench.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+set -e
+
+venv/bin/pytest tests/online/benchmark.py -vrx

scripts/deploy.sh

@@ -1,7 +1,15 @@
 #!/usr/bin/env bash
-: ${CHATMAIL_DOMAIN:=c1.testrun.org}
-export CHATMAIL_DOMAIN
-cd doveauth
-venv/bin/python3 -m build
-../chatmail-pyinfra/venv/bin/pyinfra --ssh-user root "$CHATMAIL_DOMAIN" ../deploy.py
+
+echo -----------------------------------------
+echo deploying to $CHATMAIL_DOMAIN 
+echo -----------------------------------------
+
+echo WARNING: in five seconds deploy to $CHATMAIL_DOMAIN starts
+sleep 5
+
+venv/bin/python3 -m build -n --sdist chatmaild --outdir dist
+
+venv/bin/pyinfra --ssh-user root "$CHATMAIL_DOMAIN" \
+    deploy-chatmail/src/deploy_chatmail/deploy.py
+
 rm -r dist/

scripts/generate-dns-zone.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+: ${CHATMAIL_DOMAIN:=c1.testrun.org}
+: ${CHATMAIL_SSH:=$CHATMAIL_DOMAIN}
+
+set -e
+SSH="ssh root@$CHATMAIL_SSH"
+EMAIL="root@$CHATMAIL_DOMAIN"
+ACME_ACCOUNT_URL="$($SSH -- acmetool account-url)"
+
+cat <<EOF
+$CHATMAIL_DOMAIN. MX 10 $CHATMAIL_DOMAIN.
+$CHATMAIL_DOMAIN. TXT "v=spf1 a:$CHATMAIL_DOMAIN -all"
+_dmarc.$CHATMAIL_DOMAIN. TXT "v=DMARC1;p=reject;rua=mailto:$EMAIL;ruf=mailto:$EMAIL;fo=1;adkim=r;aspf=r"
+_submission._tcp.$CHATMAIL_DOMAIN.  SRV 0 1 587 $CHATMAIL_DOMAIN.
+_submissions._tcp.$CHATMAIL_DOMAIN. SRV 0 1 465 $CHATMAIL_DOMAIN.
+_imap._tcp.$CHATMAIL_DOMAIN.        SRV 0 1 143 $CHATMAIL_DOMAIN.
+_imaps._tcp.$CHATMAIL_DOMAIN.       SRV 0 1 993 $CHATMAIL_DOMAIN.
+$CHATMAIL_DOMAIN. IN CAA 128 issue "letsencrypt.org; accounturi=$ACME_ACCOUNT_URL"
+EOF
+$SSH opendkim-genzone -F | sed 's/^;.*$//;/^$/d'

scripts/get_imap_capabilities.py

@@ -0,0 +1,14 @@
+import os
+import time
+import imaplib
+
+domain = os.environ.get("CHATMAIL_DOMAIN", "c3.testrun.org")
+
+print("connecting")
+conn = imaplib.IMAP4_SSL(domain)
+print("logging in")
+conn.login(f"imapcapa", "pass")
+status, res = conn.capability()
+for capa in sorted(res[0].decode().split()):
+    print(capa)
+

scripts/init.sh

@@ -1,8 +1,8 @@
 #!/bin/sh
-python3 -m venv chatmail-pyinfra/venv
-chatmail-pyinfra/venv/bin/pip install pyinfra pytest
-chatmail-pyinfra/venv/bin/pip install -e chatmail-pyinfra
-chatmail-pyinfra/venv/bin/pip install -e doveauth
-python3 -m venv doveauth/venv
-doveauth/venv/bin/pip install pytest build
-doveauth/venv/bin/pip install -e doveauth
+set -e
+python3 -m venv venv
+pip=venv/bin/pip
+
+$pip install pyinfra pytest build 'setuptools>=68' tox deltachat
+$pip install -e deploy-chatmail 
+$pip install -e chatmaild 

scripts/measure_tls_and_logins.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+import os
+import time
+import imaplib
+
+domain = os.environ.get("CHATMAIL_DOMAIN", "c3.testrun.org")
+
+NUM_CONNECTIONS=10
+
+conns = []
+
+start = time.time()
+for i in range(NUM_CONNECTIONS):
+    print(f"opening connection {i} to {domain}")
+    conn = imaplib.IMAP4_SSL(domain)
+    conns.append(conn)
+
+tlsdone = time.time()
+duration = tlsdone-start
+print(f"{duration}: TLS connections opening TLS connections")
+
+for i, conn in enumerate(conns):
+    print(f"logging into connection {i}")
+    conn.login(f"measure{i}", "pass")
+
+logindone = time.time()
+duration = logindone - tlsdone
+print(f"{duration}: LOGINS done")

scripts/remote-deploy.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+set -e
+
+: ${CHATMAIL_DOMAIN:=c1.testrun.org}
+: ${CHATMAIL_SSH:=$CHATMAIL_DOMAIN}
+
+rsync -avz . "root@$CHATMAIL_SSH:/root/chatmail" --exclude='/.git' --filter="dir-merge,- .gitignore"
+ssh "root@$CHATMAIL_SSH" "cd /root/chatmail; apt install -y python3-venv; python3 -m venv venv; venv/bin/pip install pyinfra build; venv/bin/python3 -m build -n --sdist chatmaild --outdir dist; venv/bin/pip install -e ./deploy-chatmail -e ./chatmaild; export CHATMAIL_DOMAIN=$CHATMAIL_DOMAIN; venv/bin/pyinfra @local deploy.py"

scripts/test.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
-chatmail-pyinfra/venv/bin/pytest chatmail-pyinfra/tests
-cd doveauth/src/doveauth
-../../venv/bin/pytest
+#!/bin/bash
+venv/bin/tox -c chatmaild
+venv/bin/tox -c deploy-chatmail
+venv/bin/pytest tests/online -rs -vrx --durations=5 $@

tests/chatmaild/test_doveauth.py

@@ -0,0 +1,86 @@
+import json
+
+import pytest
+import threading
+import queue
+import traceback
+
+import chatmaild.doveauth
+from chatmaild.doveauth import get_user_data, lookup_passdb, handle_dovecot_request
+from chatmaild.database import Database, DBError
+
+
+def test_basic(db):
+    lookup_passdb(db, "link2xt@c1.testrun.org", "Pieg9aeToe3eghuthe5u")
+    data = get_user_data(db, "link2xt@c1.testrun.org")
+    assert data
+    data2 = lookup_passdb(db, "link2xt@c1.testrun.org", "Pieg9aeToe3eghuthe5u")
+    assert data == data2
+
+
+def test_dont_overwrite_password_on_wrong_login(db):
+    """Test that logging in with a different password doesn't create a new user"""
+    res = lookup_passdb(db, "newuser1@something.org", "kajdlkajsldk12l3kj1983")
+    assert res["password"]
+    res2 = lookup_passdb(db, "newuser1@something.org", "kajdlqweqwe")
+    # this function always returns a password hash, which is actually compared by dovecot.
+    assert res["password"] == res2["password"]
+
+
+def test_nocreate_file(db, monkeypatch, tmpdir):
+    p = tmpdir.join("nocreate")
+    p.write("")
+    monkeypatch.setattr(chatmaild.doveauth, "NOCREATE_FILE", str(p))
+    lookup_passdb(db, "newuser1@something.org", "zequ0Aimuchoodaechik")
+    assert not get_user_data(db, "newuser1@something.org")
+
+
+def test_db_version(db):
+    assert db.get_schema_version() == 1
+
+
+def test_too_high_db_version(db):
+    with db.write_transaction() as conn:
+        conn.execute("PRAGMA user_version=%s;" % (999,))
+    with pytest.raises(DBError):
+        db.ensure_tables()
+
+
+def test_handle_dovecot_request(db):
+    msg = (
+        "Lshared/passdb/laksjdlaksjdlaksjdlk12j3l1k2j3123/"
+        "some42@c3.testrun.org\tsome42@c3.testrun.org"
+    )
+    res = handle_dovecot_request(msg, db, "c3.testrun.org")
+    assert res
+    assert res[0] == "O" and res.endswith("\n")
+    userdata = json.loads(res[1:].strip())
+    assert userdata["home"] == "/home/vmail/some42@c3.testrun.org"
+    assert userdata["uid"] == userdata["gid"] == "vmail"
+    assert userdata["password"].startswith("{SHA512-CRYPT}")
+
+
+def test_100_concurrent_lookups(db):
+    num = 100
+    dbs = [Database(db.path) for i in range(num)]
+    print(f"created {num} databases")
+    results = queue.Queue()
+
+    def lookup(db):
+        try:
+            lookup_passdb(db, "something@c1.testrun.org", "Pieg9aeToe3eghuthe5u")
+        except Exception:
+            results.put(traceback.format_exc())
+        else:
+            results.put(None)
+
+    threads = [threading.Thread(target=lookup, args=(db,), daemon=True) for db in dbs]
+
+    print(f"created {num} threads, starting them and waiting for results")
+    for thread in threads:
+        thread.start()
+
+    for _ in dbs:
+        res = results.get()
+        if res is not None:
+            pytest.fail(f"concurrent lookup failed\n{res}")

tests/chatmaild/test_filtermail.py

@@ -0,0 +1,82 @@
+from chatmaild.filtermail import check_encrypted, check_DATA, SendRateLimiter, check_mdn
+import pytest
+
+
+@pytest.fixture
+def maildomain():
+    # let's not depend on a real chatmail instance for the offline tests below
+    return "chatmail.example.org"
+
+
+def test_reject_forged_from(maildata, gencreds):
+    class env:
+        mail_from = gencreds()[0]
+        rcpt_tos = [gencreds()[0]]
+
+    # test that the filter lets good mail through
+    env.content = maildata("plain.eml", from_addr=env.mail_from).as_bytes()
+    assert not check_DATA(envelope=env)
+
+    # test that the filter rejects forged mail
+    env.content = maildata("plain.eml", from_addr="forged@c3.testrun.org").as_bytes()
+    error = check_DATA(envelope=env)
+    assert "500" in error
+
+
+def test_filtermail_no_encryption_detection(maildata):
+    msg = maildata("plain.eml")
+    assert not check_encrypted(msg)
+
+    # https://xkcd.com/1181/
+    msg = maildata("fake-encrypted.eml")
+    assert not check_encrypted(msg)
+
+
+def test_filtermail_encryption_detection(maildata):
+    msg = maildata("encrypted.eml")
+    assert check_encrypted(msg)
+
+    # if the subject is not "..." it is not considered ac-encrypted
+    msg.replace_header("Subject", "Click this link")
+    assert not check_encrypted(msg)
+
+
+def test_filtermail_is_mdn(maildata, gencreds):
+    from_addr = gencreds()[0]
+    to_addr = gencreds()[0] + ".other"
+    msg = maildata("mdn.eml", from_addr, to_addr)
+
+    class env:
+        mail_from = from_addr
+        rcpt_tos = [to_addr]
+        content = msg.as_bytes()
+
+    assert check_mdn(msg, env)
+    print(msg.as_string())
+    assert not check_DATA(env)
+
+
+def test_filtermail_to_multiple_recipients_no_mdn(maildata, gencreds):
+    from_addr = gencreds()[0]
+    to_addr = gencreds()[0] + ".other"
+    thirdaddr = gencreds()[0]
+    msg = maildata("mdn.eml", from_addr, to_addr)
+
+    class env:
+        mail_from = from_addr
+        rcpt_tos = [to_addr, thirdaddr]
+        content = msg.as_bytes()
+
+    assert not check_mdn(msg, env)
+
+
+def test_send_rate_limiter():
+    limiter = SendRateLimiter()
+    for i in range(100):
+        if limiter.is_sending_allowed("some@example.org"):
+            if i <= SendRateLimiter.MAX_USER_SEND_PER_MINUTE:
+                continue
+            pytest.fail("limiter didn't work")
+        else:
+            assert i == SendRateLimiter.MAX_USER_SEND_PER_MINUTE + 1
+            break

tests/conftest.py

@@ -0,0 +1,390 @@
+import os
+import io
+import time
+import random
+import subprocess
+import imaplib
+import smtplib
+import itertools
+from email.parser import BytesParser
+from email import policy
+from pathlib import Path
+import pytest
+
+from chatmaild.database import Database
+
+
+conftestdir = Path(__file__).parent
+
+
+def pytest_addoption(parser):
+    parser.addoption(
+        "--slow", action="store_true", default=False, help="also run slow tests"
+    )
+
+
+def pytest_configure(config):
+    config._benchresults = {}
+    config.addinivalue_line(
+        "markers", "slow: mark test to require --slow option to run"
+    )
+
+
+def pytest_runtest_setup(item):
+    markers = list(item.iter_markers(name="slow"))
+    if markers:
+        if not item.config.getoption("--slow"):
+            pytest.skip("skipping slow test, use --slow to run")
+
+
+@pytest.fixture
+def maildomain():
+    domain = os.environ.get("CHATMAIL_DOMAIN")
+    if not domain:
+        pytest.skip("set CHATMAIL_DOMAIN to a ssh-reachable chatmail instance")
+    return domain
+
+
+@pytest.fixture
+def sshdomain(maildomain):
+    return os.environ.get("CHATMAIL_SSH", maildomain)
+
+
+@pytest.fixture
+def maildomain2():
+    domain = os.environ.get("CHATMAIL_DOMAIN2")
+    if not domain:
+        pytest.skip("set CHATMAIL_DOMAIN2 to a ssh-reachable chatmail instance")
+    return domain
+
+
+@pytest.fixture
+def sshdomain2(maildomain2):
+    return os.environ.get("CHATMAIL_SSH2", maildomain2)
+
+
+def pytest_report_header():
+    domain = os.environ.get("CHATMAIL_DOMAIN")
+    if domain:
+        text = f"chatmail test instance: {domain}"
+        return ["-" * len(text), text, "-" * len(text)]
+
+
+@pytest.fixture
+def benchmark(request):
+    def bench(func, num, name=None, reportfunc=None):
+        if name is None:
+            name = func.__name__
+        durations = []
+        for i in range(num):
+            now = time.time()
+            func()
+            durations.append(time.time() - now)
+        durations.sort()
+        request.config._benchresults[name] = (reportfunc, durations)
+
+    return bench
+
+
+def pytest_terminal_summary(terminalreporter):
+    tr = terminalreporter
+    results = tr.config._benchresults
+    if not results:
+        return
+
+    tr.section("benchmark results")
+    float_names = "median min max".split()
+    width = max(map(len, float_names))
+
+    def fcol(parts):
+        return " ".join(part.rjust(width) for part in parts)
+
+    headers = f"{'benchmark name': <30} " + fcol(float_names)
+    tr.write_line(headers)
+    tr.write_line("-" * len(headers))
+    summary_lines = []
+
+    for name, (reportfunc, durations) in results.items():
+        measures = [
+            sorted(durations)[len(durations) // 2],
+            min(durations),
+            max(durations),
+        ]
+        line = f"{name: <30} "
+        line += fcol(f"{float: 2.2f}" for float in measures)
+        tr.write_line(line)
+        vmedian, vmin, vmax = measures
+        if reportfunc:
+            for line in reportfunc(vmin=vmin, vmedian=vmedian, vmax=vmax):
+                summary_lines.append(line)
+
+    if summary_lines:
+        tr.write_line("")
+        tr.section("benchmark summary measures")
+        for line in summary_lines:
+            tr.write_line(line)
+
+
+@pytest.fixture
+def imap(maildomain):
+    return ImapConn(maildomain)
+
+
+@pytest.fixture
+def make_imap_connection(maildomain):
+    def make_imap_connection():
+        conn = ImapConn(maildomain)
+        conn.connect()
+        return conn
+
+    return make_imap_connection
+
+
+class ImapConn:
+    AuthError = imaplib.IMAP4.error
+    logcmd = "journalctl -f -u dovecot"
+    name = "dovecot"
+
+    def __init__(self, host):
+        self.host = host
+
+    def connect(self):
+        print(f"imap-connect {self.host}")
+        self.conn = imaplib.IMAP4_SSL(self.host)
+
+    def login(self, user, password):
+        print(f"imap-login {user!r} {password!r}")
+        self.conn.login(user, password)
+
+    def fetch_all(self):
+        print("imap-fetch all")
+        status, res = self.conn.select()
+        if int(res[0]) == 0:
+            raise ValueError("no messages in imap folder")
+        status, results = self.conn.fetch("1:*", "(RFC822)")
+        assert status == "OK"
+        return results
+
+    def fetch_all_messages(self):
+        print("imap-fetch all messages")
+        results = self.fetch_all()
+        messages = []
+        for item in results:
+            if len(item) == 2:
+                messages.append(item[1].decode())
+        return messages
+
+
+@pytest.fixture
+def smtp(maildomain):
+    return SmtpConn(maildomain)
+
+
+@pytest.fixture
+def make_smtp_connection(maildomain):
+    def make_smtp_connection():
+        conn = SmtpConn(maildomain)
+        conn.connect()
+        return conn
+
+    return make_smtp_connection
+
+
+class SmtpConn:
+    AuthError = smtplib.SMTPAuthenticationError
+    logcmd = "journalctl -f -t postfix/smtpd -t postfix/smtp -t postfix/lmtp"
+    name = "postfix"
+
+    def __init__(self, host):
+        self.host = host
+
+    def connect(self):
+        print(f"smtp-connect {self.host}")
+        self.conn = smtplib.SMTP_SSL(self.host)
+
+    def login(self, user, password):
+        print(f"smtp-login {user!r} {password!r}")
+        self.conn.login(user, password)
+
+    def sendmail(self, from_addr, to_addrs, msg):
+        print(f"smtp-sendmail from={from_addr!r} to_addrs={to_addrs!r}")
+        print(f"smtp-sendmail message size: {len(msg)}")
+        return self.conn.sendmail(from_addr=from_addr, to_addrs=to_addrs, msg=msg)
+
+
+@pytest.fixture(params=["imap", "smtp"])
+def imap_or_smtp(request):
+    return request.getfixturevalue(request.param)
+
+
+@pytest.fixture
+def gencreds(maildomain):
+    count = itertools.count()
+    next(count)
+
+    def gen(domain=None):
+        domain = domain if domain else maildomain
+        while 1:
+            num = next(count)
+            alphanumeric = "abcdefghijklmnopqrstuvwxyz1234567890"
+            user = "".join(random.choices(alphanumeric, k=10))
+            user = f"ac{num}_{user}"[:9]
+            password = "".join(random.choices(alphanumeric, k=12))
+            yield f"{user}@{domain}", f"{password}"
+
+    return lambda domain=None: next(gen(domain))
+
+
+@pytest.fixture()
+def db(tmpdir):
+    db_path = tmpdir / "passdb.sqlite"
+    print("database path:", db_path)
+    return Database(db_path)
+
+
+#
+# Delta Chat testplugin re-use
+# use the cmfactory fixture to get chatmail instance accounts
+#
+
+
+class ChatmailTestProcess:
+    """Provider for chatmail instance accounts as used by deltachat.testplugin.acfactory"""
+
+    def __init__(self, pytestconfig, maildomain, gencreds):
+        self.pytestconfig = pytestconfig
+        self.maildomain = maildomain
+        assert "." in self.maildomain, maildomain
+        self.gencreds = gencreds
+        self._addr2files = {}
+
+    def get_liveconfig_producer(self):
+        while 1:
+            user, password = self.gencreds(self.maildomain)
+            config = {
+                "addr": user,
+                "mail_pw": password,
+            }
+            # speed up account configuration
+            config["mail_server"] = self.maildomain
+            config["send_server"] = self.maildomain
+            yield config
+
+    def cache_maybe_retrieve_configured_db_files(self, cache_addr, db_target_path):
+        pass
+
+    def cache_maybe_store_configured_db_files(self, acc):
+        pass
+
+
+@pytest.fixture
+def cmfactory(request, gencreds, tmpdir, data, maildomain):
+    # cloned from deltachat.testplugin.amfactory
+    pytest.importorskip("deltachat")
+    from deltachat.testplugin import ACFactory
+
+    testproc = ChatmailTestProcess(request.config, maildomain, gencreds)
+    am = ACFactory(request=request, tmpdir=tmpdir, testprocess=testproc, data=data)
+
+    # nb. a bit hacky
+    # would probably be better if deltachat's test machinery grows native support
+    def switch_maildomain(maildomain2):
+        am.testprocess.maildomain = maildomain2
+
+    am.switch_maildomain = switch_maildomain
+
+    yield am
+    if hasattr(request.node, "rep_call") and request.node.rep_call.failed:
+        if testproc.pytestconfig.getoption("--extra-info"):
+            logfile = io.StringIO()
+            am.dump_imap_summary(logfile=logfile)
+            print(logfile.getvalue())
+            # request.node.add_report_section("call", "imap-server-state", s)
+
+
+@pytest.fixture
+def remote(sshdomain):
+    return Remote(sshdomain)
+
+
+class Remote:
+    def __init__(self, sshdomain):
+        self.sshdomain = sshdomain
+
+    def iter_output(self, logcmd=""):
+        getjournal = "journalctl -f" if not logcmd else logcmd
+        self.popen = subprocess.Popen(
+            ["ssh", f"root@{self.sshdomain}", getjournal],
+            stdout=subprocess.PIPE,
+        )
+        while 1:
+            line = self.popen.stdout.readline()
+            res = line.decode().strip().lower()
+            if res:
+                yield res
+            else:
+                break
+
+
+@pytest.fixture
+def maildata(request, gencreds):
+    datadir = conftestdir.joinpath("mail-data")
+
+    def maildata(name, from_addr=None, to_addr=None):
+        if from_addr is None:
+            from_addr = gencreds()[0]
+        if to_addr is None:
+            to_addr = gencreds()[0]
+        data = datadir.joinpath(name).read_text()
+        text = data.format(from_addr=from_addr, to_addr=to_addr)
+        return BytesParser(policy=policy.default).parsebytes(text.encode())
+
+    return maildata
+
+
+@pytest.fixture
+def cmsetup(maildomain, gencreds):
+    return CMSetup(maildomain, gencreds)
+
+
+class CMSetup:
+    def __init__(self, maildomain, gencreds):
+        self.maildomain = maildomain
+        self.gencreds = gencreds
+
+    def gen_users(self, num):
+        print(f"Creating {num} online users")
+        users = []
+        for i in range(num):
+            addr, password = self.gencreds()
+            user = CMUser(self.maildomain, addr, password)
+            assert user.smtp
+            users.append(user)
+        return users
+
+
+class CMUser:
+    def __init__(self, maildomain, addr, password):
+        self.maildomain = maildomain
+        self.addr = addr
+        self.password = password
+        self._smtp = None
+        self._imap = None
+
+    @property
+    def smtp(self):
+        if not self._smtp:
+            handle = SmtpConn(self.maildomain)
+            handle.connect()
+            handle.login(self.addr, self.password)
+            self._smtp = handle
+        return self._smtp
+
+    @property
+    def imap(self):
+        if not self._imap:
+            imap = ImapConn(self.maildomain)
+            imap.connect()
+            imap.login(self.addr, self.password)
+            self._imap = imap
+        return self._imap

tests/mail-data/encrypted.eml

@@ -0,0 +1,66 @@
+From: {from_addr}
+To: {to_addr}
+Subject: ...
+Date: Sun, 15 Oct 2023 16:43:21 +0000
+Message-ID: <Mr.UVyJWZmkCKM.hGzNc6glBE_@c2.testrun.org>
+In-Reply-To: <Mr.MvmCz-GQbi_.6FGRkhDf05c@c2.testrun.org>
+References: <Mr.3gckbNy5bch.uK3Hd2Ws6-w@c2.testrun.org>
+	<Mr.MvmCz-GQbi_.6FGRkhDf05c@c2.testrun.org>
+Chat-Version: 1.0
+Autocrypt: addr={from_addr}; prefer-encrypt=mutual;
+	keydata=xjMEZSwWjhYJKwYBBAHaRw8BAQdAQBEhqeJh0GueHB6kF/DUQqYCxARNBVokg/AzT+7LqH
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+	IXnYw4CKd55UAwl8Zcy+M2diAbkA/0fHHcGV4r78hpbbL1Os52DPOdqYQRauIeJUeG+G6bQO
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+Content-Type: multipart/encrypted; protocol="application/pgp-encrypted";
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+
+

tests/mail-data/fake-encrypted.eml

@@ -0,0 +1,25 @@
+Subject: =?utf-8?q?Message_from_foobar=40c2=2Etestrun=2Eorg?=
+Chat-Disposition-Notification-To: foobar@c2.testrun.org
+Chat-User-Avatar: 0
+From: <{from_addr}>
+To: <{to_addr}>
+Date: Sun, 15 Oct 2023 16:41:44 +0000
+Message-ID: <Mr.3gckbNy5bch.uK3Hd2Ws6-w@c2.testrun.org>
+References: <Mr.3gckbNy5bch.uK3Hd2Ws6-w@c2.testrun.org>
+Chat-Version: 1.0
+Autocrypt: addr={from_addr}; prefer-encrypt=mutual;
+	keydata=xjMEZSrw3hYJKwYBBAHaRw8BAQdAiEKNQFU28c6qsx4vo/JHdt73RXdjMOmByf/XsGiJ7m
+	nNFzxmb29iYXJAYzIudGVzdHJ1bi5vcmc+wosEEBYIADMCGQEFAmUq8N4CGwMECwkIBwYVCAkKCwID
+	FgIBFiEEGil0OvTIa6RngmCLUYNnEa9leJAACgkQUYNnEa9leJCX3gEAhm0MehE5byBBU1avPczr/I
+	HjNLht7Qf6++mAhlJmtDcA/0C8VYJhsUpmiDjuZaMDWNv4FO2BJG6LH7gSm6n7ClMJzjgEZSrw3hIK
+	KwYBBAGXVQEFAQEHQAxGG/QW0owCfMp1A+vXEMwgzWcBpNFr58kX2eXuPpM6AwEIB8J4BBgWCAAgBQ
+	JlKvDeAhsMFiEEGil0OvTIa6RngmCLUYNnEa9leJAACgkQUYNnEa9leJDg1gEAwLf8KDoAAKyYgjyI
+	vYvO9VEgBni1C4Xx1VjcaEmlDK8BALoFuUCK+enw76TtDcAUKhlhUiM6SDRExkS4Nskp/BcK
+MIME-Version: 1.0
+Content-Type: text/plain; charset=utf-8; format=flowed; delsp=no
+
+-----BEGIN PGP MESSAGE-----
+Hi!
+-----END PGP MESSAGE-----
+
+

tests/mail-data/mdn.eml

@@ -0,0 +1,33 @@
+Subject: Message opened
+From: <{from_addr}>
+To: <{to_addr}>
+Date: Sun, 15 Oct 2023 16:43:25 +0000
+Message-ID: <Mr.78MWtlV7RAi.goCFzBhCYfy@c2.testrun.org>
+Auto-Submitted: auto-replied
+Chat-Version: 1.0
+MIME-Version: 1.0
+Content-Type: multipart/report; report-type=disposition-notification;
+	boundary="Gl92xgZjOShJ5PGHntqYkoo2OK2Dvi"
+
+
+--Gl92xgZjOShJ5PGHntqYkoo2OK2Dvi
+Content-Type: text/plain; charset=utf-8; format=flowed; delsp=no
+
+The "Hi!" message you sent was displayed on the screen of the recipient.
+
+This is no guarantee the content was read.
+
+
+--Gl92xgZjOShJ5PGHntqYkoo2OK2Dvi
+Content-Type: message/disposition-notification
+
+Reporting-UA: Delta Chat 1.124.1
+Original-Recipient: rfc822;barbaz@c2.testrun.org
+Final-Recipient: rfc822;barbaz@c2.testrun.org
+Original-Message-ID: <Mr.MvmCz-GQbi_.6FGRkhDf05c@c2.testrun.org>
+Disposition: manual-action/MDN-sent-automatically; displayed
+
+
+--Gl92xgZjOShJ5PGHntqYkoo2OK2Dvi--
+
+

tests/mail-data/plain.eml

@@ -0,0 +1,23 @@
+Subject: =?utf-8?q?Message_from_foobar=40c2=2Etestrun=2Eorg?=
+Chat-Disposition-Notification-To: foobar@c2.testrun.org
+Chat-User-Avatar: 0
+From: <{from_addr}>
+To: <{to_addr}>
+Date: Sun, 15 Oct 2023 16:41:44 +0000
+Message-ID: <Mr.3gckbNy5bch.uK3Hd2Ws6-w@c2.testrun.org>
+References: <Mr.3gckbNy5bch.uK3Hd2Ws6-w@c2.testrun.org>
+Chat-Version: 1.0
+Autocrypt: addr=foobar@c2.testrun.org; prefer-encrypt=mutual;
+	keydata=xjMEZSrw3hYJKwYBBAHaRw8BAQdAiEKNQFU28c6qsx4vo/JHdt73RXdjMOmByf/XsGiJ7m
+	nNFzxmb29iYXJAYzIudGVzdHJ1bi5vcmc+wosEEBYIADMCGQEFAmUq8N4CGwMECwkIBwYVCAkKCwID
+	FgIBFiEEGil0OvTIa6RngmCLUYNnEa9leJAACgkQUYNnEa9leJCX3gEAhm0MehE5byBBU1avPczr/I
+	HjNLht7Qf6++mAhlJmtDcA/0C8VYJhsUpmiDjuZaMDWNv4FO2BJG6LH7gSm6n7ClMJzjgEZSrw3hIK
+	KwYBBAGXVQEFAQEHQAxGG/QW0owCfMp1A+vXEMwgzWcBpNFr58kX2eXuPpM6AwEIB8J4BBgWCAAgBQ
+	JlKvDeAhsMFiEEGil0OvTIa6RngmCLUYNnEa9leJAACgkQUYNnEa9leJDg1gEAwLf8KDoAAKyYgjyI
+	vYvO9VEgBni1C4Xx1VjcaEmlDK8BALoFuUCK+enw76TtDcAUKhlhUiM6SDRExkS4Nskp/BcK
+MIME-Version: 1.0
+Content-Type: text/plain; charset=utf-8; format=flowed; delsp=no
+
+Hi!
+
+

tests/online/benchmark.py

@@ -0,0 +1,60 @@
+def test_tls_imap(benchmark, imap):
+    def imap_connect():
+        imap.connect()
+
+    benchmark(imap_connect, 10)
+
+
+def test_login_imap(benchmark, imap, gencreds):
+    def imap_connect_and_login():
+        imap.connect()
+        imap.login(*gencreds())
+
+    benchmark(imap_connect_and_login, 10)
+
+
+def test_tls_smtp(benchmark, smtp):
+    def smtp_connect():
+        smtp.connect()
+
+    benchmark(smtp_connect, 10)
+
+
+def test_login_smtp(benchmark, smtp, gencreds):
+    def smtp_connect_and_login():
+        smtp.connect()
+        smtp.login(*gencreds())
+
+    benchmark(smtp_connect_and_login, 10)
+
+
+class TestDC:
+    def test_autoconfigure(self, benchmark, cmfactory):
+        def autoconfig_and_idle_ready():
+            cmfactory.get_online_accounts(1)
+
+        benchmark(autoconfig_and_idle_ready, 5)
+
+    def test_ping_pong(self, benchmark, cmfactory):
+        ac1, ac2 = cmfactory.get_online_accounts(2)
+        chat = cmfactory.get_accepted_chat(ac1, ac2)
+
+        def ping_pong():
+            chat.send_text("ping")
+            msg = ac2.wait_next_incoming_message()
+            msg.chat.send_text("pong")
+            ac1.wait_next_incoming_message()
+
+        benchmark(ping_pong, 5)
+
+    def test_send_10_receive_10(self, benchmark, cmfactory, lp):
+        ac1, ac2 = cmfactory.get_online_accounts(2)
+        chat = cmfactory.get_accepted_chat(ac1, ac2)
+
+        def send_10_receive_10():
+            for i in range(10):
+                chat.send_text(f"hello {i}")
+            for i in range(10):
+                ac2.wait_next_incoming_message()
+
+        benchmark(send_10_receive_10, 5)

tests/online/test_0_login.py

@@ -0,0 +1,70 @@
+import pytest
+import threading
+import queue
+
+
+def test_login_basic_functioning(imap_or_smtp, gencreds, lp):
+    """Test a) that an initial login creates a user automatically
+    and b) verify we can also login a second time with the same password
+    and c) that using a different password fails the login."""
+    user, password = gencreds()
+    lp.sec(f"login first time with {user} {password}")
+    imap_or_smtp.connect()
+    imap_or_smtp.login(user, password)
+    lp.indent("success")
+
+    lp.sec(f"reconnect and login second time {user} {password}")
+    imap_or_smtp.connect()
+    imap_or_smtp.login(user, password)
+    imap_or_smtp.connect()
+    lp.sec("success")
+
+    lp.sec(f"reconnect and verify wrong password fails {user} ")
+    imap_or_smtp.connect()
+    with pytest.raises(imap_or_smtp.AuthError):
+        imap_or_smtp.login(user, password + "wrong")
+
+    lp.sec("creating users with a short password is not allowed")
+    user, _password = gencreds()
+    with pytest.raises(imap_or_smtp.AuthError):
+        imap_or_smtp.login(user, "admin")
+
+
+def test_login_same_password(imap_or_smtp, gencreds):
+    """Test two different users logging in with the same password
+    to ensure that authentication process does not confuse the users
+    by using only the password hash as a key.
+    """
+    user1, password1 = gencreds()
+    user2, _ = gencreds()
+    imap_or_smtp.connect()
+    imap_or_smtp.login(user1, password1)
+    imap_or_smtp.connect()
+    imap_or_smtp.login(user2, password1)
+
+
+def test_concurrent_logins_same_account(
+    make_imap_connection, make_smtp_connection, gencreds
+):
+    """Test concurrent smtp and imap logins
+    and check remote server succeeds on each connection.
+    """
+    user1, password1 = gencreds()
+    login_results = queue.Queue()
+
+    def login_smtp_imap(smtp, imap):
+        try:
+            imap.login(user1, password1)
+        except Exception:
+            login_results.put(False)
+        else:
+            login_results.put(True)
+
+    conns = [(make_smtp_connection(), make_imap_connection()) for i in range(10)]
+
+    for args in conns:
+        thread = threading.Thread(target=login_smtp_imap, args=args, daemon=True)
+        thread.start()
+
+    for _ in conns:
+        assert login_results.get()

tests/online/test_1_basic.py

@@ -0,0 +1,63 @@
+import smtplib
+import pytest
+
+
+def test_remote(remote, imap_or_smtp):
+    lineproducer = remote.iter_output(imap_or_smtp.logcmd)
+    imap_or_smtp.connect()
+    assert imap_or_smtp.name in next(lineproducer)
+
+
+def test_use_two_chatmailservers(cmfactory, maildomain2):
+    ac1 = cmfactory.new_online_configuring_account(cache=False)
+    cmfactory.switch_maildomain(maildomain2)
+    ac2 = cmfactory.new_online_configuring_account(cache=False)
+    cmfactory.bring_accounts_online()
+    cmfactory.get_accepted_chat(ac1, ac2)
+    domain1 = ac1.get_config("addr").split("@")[1]
+    domain2 = ac2.get_config("addr").split("@")[1]
+    assert domain1 != domain2
+
+
+@pytest.mark.parametrize("forgeaddr", ["internal", "someone@example.org"])
+def test_reject_forged_from(cmsetup, maildata, lp, forgeaddr):
+    user1, user3 = cmsetup.gen_users(2)
+
+    lp.sec("send encrypted message with forged from")
+    print("envelope_from", user1.addr)
+    if forgeaddr == "internal":
+        addr_to_forge = cmsetup.gen_users(1)[0].addr
+    else:
+        addr_to_forge = "someone@example.org"
+
+    print("message to inject:")
+    msg = maildata("encrypted.eml", from_addr=addr_to_forge, to_addr=user3.addr)
+    msg = msg.as_string()
+    for line in msg.split("\n")[:4]:
+        print(f"   {line}")
+
+    lp.sec("Send forged mail and check remote postfix lmtp processing result")
+    with pytest.raises(smtplib.SMTPException) as e:
+        user1.smtp.sendmail(from_addr=user1.addr, to_addrs=[user3.addr], msg=msg)
+    assert "500" in str(e.value)
+
+
+@pytest.mark.slow
+def test_exceed_rate_limit(cmsetup, gencreds, maildata):
+    """Test that the per-account send-mail limit is exceeded."""
+    user1, user2 = cmsetup.gen_users(2)
+    mail = maildata(
+        "encrypted.eml", from_addr=user1.addr, to_addr=user2.addr
+    ).as_string()
+    for i in range(100):
+        print("Sending mail", str(i))
+        try:
+            user1.smtp.sendmail(user1.addr, [user2.addr], mail)
+        except smtplib.SMTPException as e:
+            if i < 80:
+                pytest.fail(f"rate limit was exceeded too early with msg {i}")
+            outcome = e.recipients[user2.addr]
+            assert outcome[0] == 450
+            assert b"4.7.1: Too much mail from" in outcome[1]
+            return
+    pytest.fail("Rate limit was not exceeded")

tests/online/test_2_deltachat.py

@@ -0,0 +1,110 @@
+import time
+import random
+import pytest
+
+
+class TestEndToEndDeltaChat:
+    "Tests that use Delta Chat accounts on the chat mail instance."
+
+    def test_one_on_one(self, cmfactory, lp):
+        """Test that a DC account can send a message to a second DC account
+        on the same chat-mail instance."""
+        ac1, ac2 = cmfactory.get_online_accounts(2)
+        chat = cmfactory.get_accepted_chat(ac1, ac2)
+
+        lp.sec("ac1: prepare and send text message to ac2")
+        chat.send_text("message0")
+
+        lp.sec("wait for ac2 to receive message")
+        msg2 = ac2._evtracker.wait_next_incoming_message()
+        assert msg2.text == "message0"
+
+    @pytest.mark.slow
+    def test_exceed_quota(self, cmfactory, lp, tmpdir, remote):
+        """This is a very slow test as it needs to upload >100MB of mail data
+        before quota is exceeded, and thus depends on the speed of the upload.
+        """
+        ac1, ac2 = cmfactory.get_online_accounts(2)
+        chat = cmfactory.get_accepted_chat(ac1, ac2)
+
+        quota = 1024 * 1024 * 100
+        attachsize = 1 * 1024 * 1024
+        num_to_send = quota // attachsize + 2
+        lp.sec(f"ac1: send {num_to_send} large files to ac2")
+        lp.indent(f"per-user quota is assumed to be: {quota/(1024*1024)}MB")
+        alphanumeric = "abcdefghijklmnopqrstuvwxyz1234567890"
+        msgs = []
+        for i in range(num_to_send):
+            attachment = tmpdir / f"attachment{i}"
+            data = "".join(random.choice(alphanumeric) for i in range(1024))
+            with open(attachment, "w+") as f:
+                for j in range(attachsize // len(data)):
+                    f.write(data)
+
+            msg = chat.send_file(str(attachment))
+            msgs.append(msg)
+            lp.indent(f"Sent out msg {i}, size {attachsize/(1024*1024)}MB")
+
+        lp.sec("ac2: check messages are arriving until quota is reached")
+
+        addr = ac2.get_config("addr").lower()
+        saved_ok = 0
+        for line in remote.iter_output("journalctl -f -u dovecot"):
+            if addr not in line:
+                # print(line)
+                continue
+            if "quota" in line:
+                if "quota exceeded" in line:
+                    if saved_ok < num_to_send // 2:
+                        pytest.fail(
+                            f"quota exceeded too early: after {saved_ok} messages already"
+                        )
+                    lp.indent("good, message sending failed because quota was exceeded")
+                    return
+            if "saved mail to inbox" in line:
+                saved_ok += 1
+                print(f"{saved_ok}: {line}")
+                if saved_ok >= num_to_send:
+                    break
+
+        pytest.fail("sending succeeded although messages should exceed quota")
+
+    def test_securejoin(self, cmfactory, lp, maildomain2):
+        ac1 = cmfactory.new_online_configuring_account(cache=False)
+        cmfactory.switch_maildomain(maildomain2)
+        ac2 = cmfactory.new_online_configuring_account(cache=False)
+        cmfactory.bring_accounts_online()
+
+        lp.sec("ac1: create QR code and let ac2 scan it, starting the securejoin")
+        qr = ac1.get_setup_contact_qr()
+
+        lp.sec("ac2: start QR-code based setup contact protocol")
+        ch = ac2.qr_setup_contact(qr)
+        assert ch.id >= 10
+        ac1._evtracker.wait_securejoin_inviter_progress(1000)
+
+    def test_read_receipts_between_instances(self, cmfactory, lp, maildomain2):
+        ac1 = cmfactory.new_online_configuring_account(cache=False)
+        cmfactory.switch_maildomain(maildomain2)
+        ac2 = cmfactory.new_online_configuring_account(cache=False)
+        cmfactory.bring_accounts_online()
+
+        lp.sec("setup encrypted comms between ac1 and ac2 on different instances")
+        qr = ac1.get_setup_contact_qr()
+        ac2.qr_setup_contact(qr)
+        msg = ac2.wait_next_incoming_message()
+        assert "verified" in msg.text
+
+        lp.sec("ac1 sends a message and ac2 marks it as seen")
+        chat = ac1.create_chat(ac2)
+        msg = chat.send_text("hi")
+        m = ac2.wait_next_incoming_message()
+        m.mark_seen()
+        # we can only indirectly wait for mark-seen to cause an smtp-error
+        lp.sec("try to wait for markseen to complete and check error states")
+        deadline = time.time() + 3.1
+        while time.time() < deadline:
+            msgs = m.chat.get_messages()
+            for msg in msgs:
+                assert "error" not in m.get_message_info()
+            time.sleep(1)

tests/pytest.ini

@@ -0,0 +1,2 @@
+[pytest]
+addopts = -vrsx --strict-markers

www/nine.testrun.org/index.html

@@ -0,0 +1,79 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <meta charset="utf-8" />
+    <title>nine.testrun.org - Experimenting with the Future of Email</title>
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <style>
+        .wrapper {
+            width: 100%;
+            max-width: 596px;
+            margin: 0 auto;
+        }
+
+        .section {
+            width: 100%;
+            max-width: 596px;
+        }
+
+        .text {
+            box-sizing: border-box;
+            padding: 9px;
+            font-size: 18px;
+            font-family: "Courier New", monospace;
+            color: white;
+            background-position: left top;
+            background-image: url(collage-bg.png);
+            background-repeat: no-repeat;
+            background-size: 100% 100%;
+        }
+        a {
+            color: white;
+        }
+        h1, h2, h3 {
+            font-size: 16px;
+            font-weight: bold;
+        }
+    </style>
+</head>
+<body>
+    <div class="wrapper">
+        <img class="section" src="collage-top.png" />
+        <div class="section text">
+            <h1>Dear Delta Chat users,</h1>
+            <p>
+                welcome to the first public "chat-mail instance",
+                a small and lean e-mail server optimized for Delta Chat.
+            </p>
+            <ul>
+                <li>Tap "LOG INTO YOUR E-MAIL ACCOUNT". </li>
+                <li>Address: invent a word with <i>exactly</i> nine characters
+                and append @nine.testrun.org to it.</li>
+                <li>Password: invent at least 10 characters. The first login sets your password.</li>
+            </ul>
+                If the e-mail address is not yet taken, you'll get that account.
+            </p>
+        </div>
+        <img class="section" src="collage-down.png" />
+        <div class="section text">
+            <h1>faq</h1>
+            <h2>Can i chat with someone outside the chat-mail instance?</h2>
+            <p>Yes, if your messages are encrypted.
+            Use <a href="https://delta.chat/en/help#howtoe2ee">
+                guaranteed end-to-end encryption via QR code scans</a>
+            to setup contact with users outside of the chat-mail instance.</p>
+            <h2>What about current rate limits?</h2>
+            <ul>
+              <li>Sending limit: 60 messages per minute.</li>
+              <li>Message autoremoval: after 40 days.</li>
+            </ul>
+            <h2>Do you intend to keep this chat-mail instance up?</h2>
+            <p>Yes, nine.testrun.org is to run for longer, on a best-effort basis.</p>
+            <h2>Who is running this chat-mail instance?</h2>
+            <p>A small group of devs and sysadmins, reachable via root@.
+            <h2>Why are other email providers 1000 times more complicated?</h2>
+            <p>¯\_(ツ)_/¯</p>
+        </div>
+    </div>
+</body>
+</html>