support CHATMAIL_SERVER in generate-dns-zone.sh

Revert "generate-dns-zone.sh doesn't need to support CHATMAIL_SERVER env var for now, let's assume A/AAAA point to the chatmail server, too"

This reverts commit 51ebd74e700eb65594c7b42dd2179141504cf666.

.gitignore

@@ -159,3 +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

@@ -1,23 +1,61 @@
-# Chat Mail server configuration
+# Chatmail instances optimized for Delta Chat apps 
 
-This repository setups a ready-to-go chatmail instance
+This repository helps to setup a ready-to-use chatmail instance
 comprised of a minimal setup of the battle-tested 
-[postfix smtp server](https://www.postfix.org) and [dovecot imap server](https://www.dovecot.org).
+[postfix smtp](https://www.postfix.org) and [dovecot imap](https://www.dovecot.org) services. 
 
-## Getting started 
+The setup is designed and optimized for providing chatmail accounts 
+for use by [Delta Chat apps](https://delta.chat).
 
-1. prepare your local system:
+Chatmail accounts are automatically created by a first login, 
+after which the initially specified password is required for using them. 
+
+## Getting Started deploying your own chatmail instance
+
+1. Prepare your local (presumably Linux) system:
 
     scripts/init.sh 
 
-2. set environment variable to the chatmail domain you want to setup:
+2. Setup a domain with `A` and `AAAA` records for your chatmail server.
+
+3. Set environment variable to the chatmail domain you want to setup:
 
     export CHATMAIL_DOMAIN=c1.testrun.org   # replace with your host
 
-3. run the deploy of the chat mail instance: 
+4. Deploy the chat mail instance to your chatmail server: 
 
     scripts/deploy.sh 
 
+   This script uses `pyinfra` and `ssh` to setup packages and configure
+   the chatmail instance on your remote server. 
+
+5. Run `scripts/generate-dns-zone.sh` and 
+   transfer the generated DNS records at your DNS provider
+
+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. 
+
+
+### Ports
+
+Postfix listens on ports 25 (smtp) and 587 (submission) and 465 (submissions).
+Dovecot listens on ports 143(imap) and 993 (imaps).
+
+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) 
 
@@ -32,28 +70,27 @@ comprised of a minimal setup of the battle-tested
 
     scripts/bench.sh 
 
-## Running tests (offline and online) 
 
-```
-## Dovecot/Postfix configuration
+## Development Background for chatmail instances 
 
-### Ports
+This repository drives the development of "chatmail instances", 
+comprised of minimal setups of 
 
-Postfix listens on ports 25 (smtp) and 587 (submission) and 465 (submissions).
-Dovecot listens on ports 143(imap) and 993 (imaps).
+- [postfix smtp server](https://www.postfix.org) 
+- [dovecot imap server](https://www.dovecot.org) 
 
-## DNS
+as well as two custom services that are integrated with these two: 
 
-For DKIM you must add a DNS entry as found in /etc/opendkim/selector.txt on your chatmail instance.
-The above `scripts/deploy.sh` prints out the DKIM selector and DNS entry you
-need to setup with your DNS provider. 
+- `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. 
 
-## Emergency Commands
 
-If you need to stop account creation,
-e.g. because some script is wildly creating accounts,
-just run `touch /tmp/nocreate`.
-You can remove the file
-as soon as the attacker was banned
-by different means.
 

chatmaild/pyproject.toml

@@ -10,11 +10,14 @@ dependencies = [
 ]
 
 [project.scripts]
-doveauth-dictproxy = "chatmaild.dictproxy:main"
+doveauth = "chatmaild.doveauth:main"
 filtermail = "chatmaild.filtermail:main"
 
 [tool.pytest.ini_options]
 addopts = "-v -ra --strict-markers"
+log_format = "%(asctime)s %(levelname)s %(message)s"
+log_date_format = "%Y-%m-%d %H:%M:%S"
+log_level = "INFO"
 
 [tool.tox]
 legacy_tox_ini = """

chatmaild/src/chatmaild/database.py

@@ -33,13 +33,6 @@ class Connection:
     def cursor(self):
         return self._sqlconn.cursor()
 
-    def create_user(self, addr: str, password: str):
-        """Create a row in the users table."""
-        self.execute("PRAGMA foreign_keys=on")
-        q = """INSERT INTO users (addr, password, last_login)
-               VALUES (?, ?, ?)"""
-        self.execute(q, (addr, password, int(time.time())))
-
     def get_user(self, addr: str) -> {}:
         """Get a row from the users table."""
         q = "SELECT addr, password, last_login from users WHERE addr = ?"

chatmaild/src/chatmaild/doveauth.py

@@ -1,5 +1,6 @@
 import logging
 import os
+import time
 import sys
 import json
 import crypt
@@ -21,15 +22,29 @@ def encrypt_password(password: str):
     return "{SHA512-CRYPT}" + passhash
 
 
-def create_user(db, user, password):
+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"Didn't create account: {NOCREATE_FILE} exists. Delete the file to enable account creation."
-        )
-        return
-    with db.write_transaction() as conn:
-        conn.create_user(user, password)
-    return dict(home=f"/home/vmail/{user}", uid="vmail", gid="vmail", password=password)
+        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):
@@ -45,16 +60,34 @@ def lookup_userdb(db, user):
     return get_user_data(db, user)
 
 
-def lookup_passdb(db, user, password):
-    userdata = get_user_data(db, user)
-    if not userdata:
-        return create_user(db, user, encrypt_password(password))
-    userdata["password"] = userdata["password"].strip()
-    return userdata
+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):
-    print(f"received msg: {msg!r}", file=sys.stderr)
     short_command = msg[0]
     if short_command == "L":  # LOOKUP
         parts = msg[1:].split("\t")
@@ -72,19 +105,18 @@ def handle_dovecot_request(msg, db, mail_domain):
                     reply_command = "N"
             elif type == "passdb":
                 if user.endswith(f"@{mail_domain}"):
-                    res = lookup_passdb(db, user, password=args[0])
+                    res = lookup_passdb(db, user, cleartext_password=args[0])
                 if res:
                     reply_command = "O"
                 else:
                     reply_command = "N"
-        print(f"res: {res!r}", file=sys.stderr)
         json_res = json.dumps(res) if res else ""
         return f"{reply_command}{json_res}\n"
     return None
 
 
 class ThreadedUnixStreamServer(ThreadingMixIn, UnixStreamServer):
-    pass
+    request_queue_size = 100
 
 
 def main():
@@ -96,15 +128,20 @@ def main():
 
     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:
-                    print(f"sending result: {res!r}", file=sys.stderr)
-                    self.wfile.write(res.encode("ascii"))
-                    self.wfile.flush()
+            try:
+                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()
+                    else:
+                        logging.warn("request had no answer: %r", msg)
+            except Exception:
+                logging.exception("Exception in the handler")
+                raise
 
     try:
         os.unlink(socket)

chatmaild/src/chatmaild/doveauth.service

@@ -2,7 +2,7 @@
 Description=Dict authentication proxy for dovecot
 
 [Service]
-ExecStart=/usr/local/bin/doveauth-dictproxy /run/dovecot/doveauth.socket vmail /home/vmail/passdb.sqlite
+ExecStart=/usr/local/bin/doveauth /run/dovecot/doveauth.socket vmail /home/vmail/passdb.sqlite
 Restart=always
 RestartSec=30
 

chatmaild/src/chatmaild/filtermail.py

@@ -149,7 +149,7 @@ class SendRateLimiter:
 def main():
     args = sys.argv[1:]
     assert len(args) == 1
-    logging.basicConfig(level=logging.INFO)
+    logging.basicConfig(level=logging.WARN)
     loop = asyncio.new_event_loop()
     asyncio.set_event_loop(loop)
     task = asyncmain_beforequeue(port=int(args[0]))

deploy-chatmail/src/deploy_chatmail/__init__.py

@@ -4,9 +4,10 @@ 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 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
 
 
@@ -24,8 +25,8 @@ def _install_chatmaild() -> None:
         )
 
         apt.packages(
-            name="apt install python3-aiosmtpd",
-            packages=["python3-aiosmtpd", "python3-pip"],
+            name="apt install python3-aiosmtpd python3-pip python3-venv",
+            packages=["python3-aiosmtpd", "python3-pip", "python3-venv"],
         )
 
         # --no-deps because aiosmtplib is installed with `apt`.
@@ -34,8 +35,17 @@ def _install_chatmaild() -> None:
             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-dictproxy",
+            "doveauth",
             "filtermail",
         ):
             files.put(
@@ -70,6 +80,36 @@ def _configure_opendkim(domain: str, dkim_selector: str) -> bool:
         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",
@@ -90,7 +130,43 @@ def _configure_opendkim(domain: str, dkim_selector: str) -> bool:
             _sudo_user="opendkim",
         )
 
-    need_restart |= main_config.changed
+    return need_restart
+
+
+def _install_mta_sts_daemon() -> bool:
+    need_restart = False
+
+    config = files.put(
+        name="upload postfix-mta-sts-resolver config",
+        src=importlib.resources.files(__package__).joinpath(
+            "postfix/mta-sts-daemon.yml"
+        ),
+        dest="/etc/mta-sts-daemon.yml",
+        user="root",
+        group="root",
+        mode="644",
+    )
+    need_restart |= config.changed
+
+    server.shell(
+        name="install postfix-mta-sts-resolver with pip",
+        commands=[
+            "python3 -m venv /usr/local/lib/postfix-mta-sts-resolver",
+            "/usr/local/lib/postfix-mta-sts-resolver/bin/pip install postfix-mta-sts-resolver",
+        ],
+    )
+
+    systemd_unit = files.put(
+        name="upload mta-sts-daemon systemd unit",
+        src=importlib.resources.files(__package__).joinpath(
+            "postfix/mta-sts-daemon.service"
+        ),
+        dest="/etc/systemd/system/mta-sts-daemon.service",
+        user="root",
+        group="root",
+        mode="644",
+    )
+    need_restart |= systemd_unit.changed
 
     return need_restart
 
@@ -155,15 +231,26 @@ def _configure_dovecot(mail_server: str, debug: bool = False) -> bool:
         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:
+def _configure_nginx(domain: str, mail_server: str) -> bool:
     """Configures nginx HTTP server."""
     need_restart = False
 
     main_config = files.template(
-        src=importlib.resources.files(__package__).joinpath("nginx.conf.j2"),
+        src=importlib.resources.files(__package__).joinpath("nginx/nginx.conf.j2"),
         dest="/etc/nginx/nginx.conf",
         user="root",
         group="root",
@@ -173,7 +260,7 @@ def _configure_nginx(domain: str, debug: bool = False) -> bool:
     need_restart |= main_config.changed
 
     autoconfig = files.template(
-        src=importlib.resources.files(__package__).joinpath("autoconfig.xml.j2"),
+        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",
@@ -182,6 +269,16 @@ def _configure_nginx(domain: str, debug: bool = False) -> bool:
     )
     need_restart |= autoconfig.changed
 
+    mta_sts_config = files.template(
+        src=importlib.resources.files(__package__).joinpath("nginx/mta-sts.txt.j2"),
+        dest="/var/www/html/.well-known/mta-sts.txt",
+        user="root",
+        group="root",
+        mode="644",
+        config={"mail_server": mail_server},
+    )
+    need_restart |= mta_sts_config.changed
+
     return need_restart
 
 
@@ -206,7 +303,7 @@ def deploy_chatmail(mail_domain: str, mail_server: str, dkim_selector: str) -> N
     )
 
     # Deploy acmetool to have TLS certificates.
-    deploy_acmetool(nginx_hook=True, domains=[mail_server])
+    deploy_acmetool(nginx_hook=True, domains=[mail_server, f"mta-sts.{mail_server}"])
 
     apt.packages(
         name="Install Postfix",
@@ -236,7 +333,14 @@ def deploy_chatmail(mail_domain: str, mail_server: str, dkim_selector: str) -> N
     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)
+    nginx_need_restart = _configure_nginx(mail_domain, mail_server)
+    mta_sts_need_restart = _install_mta_sts_daemon()
+
+    # 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",
@@ -246,6 +350,15 @@ def deploy_chatmail(mail_domain: str, mail_server: str, dkim_selector: str) -> N
         restarted=opendkim_need_restart,
     )
 
+    systemd.service(
+        name="Start and enable MTA-STS daemon",
+        service="mta-sts-daemon.service",
+        daemon_reload=True,
+        running=True,
+        enabled=True,
+        restarted=mta_sts_need_restart,
+    )
+
     systemd.service(
         name="Start and enable Postfix",
         service="postfix.service",
@@ -292,14 +405,3 @@ def deploy_chatmail(mail_domain: str, mail_server: str, dkim_selector: str) -> N
         enabled=True,
         restarted=journald_conf,
     )
-
-    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)

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

@@ -46,8 +46,7 @@ def deploy_acmetool(nginx_hook=False, email="", domains=[]):
         mode="644",
     )
 
-    for domain in domains:
-        server.shell(
-            name=f"Request certificate for {domain}",
-            commands=[f"acmetool want {domain}"],
-        )
+    server.shell(
+        name=f"Request certificate for: { ', '.join(domains) }",
+        commands=[f"acmetool want { ' '.join(domains)}"],
+    )

deploy-chatmail/src/deploy_chatmail/deploy.py

@@ -6,7 +6,7 @@ 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/dovecot.conf.j2

@@ -19,7 +19,7 @@ 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
+imap_capability = IMAP4rev1 IDLE MOVE QUOTA CONDSTORE NOTIFY
 
 
 # Authentication for system users.
@@ -118,6 +118,24 @@ service auth-worker {
   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
 ssl_cert = </var/lib/acme/live/{{ config.hostname }}/fullchain
 ssl_key = </var/lib/acme/live/{{ config.hostname }}/privkey

deploy-chatmail/src/deploy_chatmail/nginx/mta-sts.txt.j2

@@ -0,0 +1,4 @@
+version: STSv1
+mode: enforce
+mx: {{ config.mail_server }}
+max_age: 2419200

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

@@ -20,8 +20,6 @@ http {
 
 	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;
 
@@ -30,6 +28,8 @@ http {
 		listen [::]:80 default_server;
 		listen 443 ssl default_server;
 		listen [::]:443 ssl default_server;
+        ssl_certificate /var/lib/acme/live/{{ config.domain_name }}/fullchain;
+        ssl_certificate_key /var/lib/acme/live/{{ config.domain_name }}/privkey;
 
 		root /var/www/html;
 
@@ -37,6 +37,28 @@ http {
 
 		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;
+		}
+	}
+	server {
+		listen 80;
+		listen [::]:80;
+		listen 443 ssl;
+		listen [::]:443 ssl;
+
+		root /var/www/html;
+
+		index index.html index.htm;
+
+		server_name mta-sts.{{ config.domain_name }};
+
+        ssl_certificate /var/lib/acme/live/mta-sts.{{ config.domain_name }}/fullchain;
+    	ssl_certificate_key /var/lib/acme/live/mta-sts.{{ config.domain_name }}/privkey;
+
+
 		location / {
 			# First attempt to serve request as file, then
 			# as directory, then fall back to displaying a 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

@@ -23,6 +23,7 @@ smtpd_tls_security_level=may
 smtp_tls_CApath=/etc/ssl/certs
 smtp_tls_security_level=may
 smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
+smtp_tls_policy_maps = socketmap:inet:127.0.0.1:8461:postfix
 
 smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
 myhostname = {{ config.domain_name }}

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

@@ -32,6 +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_client_connection_count_limit=1000
   -o smtpd_proxy_filter=127.0.0.1:10080
 smtps     inet  n       -       y       -       -       smtpd
   -o syslog_name=postfix/smtps
@@ -46,6 +47,7 @@ smtps     inet  n       -       y       -       -       smtpd
   -o smtpd_sender_restrictions=$mua_sender_restrictions
   -o smtpd_recipient_restrictions=
   -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
+  -o smtpd_client_connection_count_limit=1000
   -o milter_macro_daemon_name=ORIGINATING
   -o smtpd_proxy_filter=127.0.0.1:10080
 #628       inet  n       -       y       -       -       qmqpd

deploy-chatmail/src/deploy_chatmail/postfix/mta-sts-daemon.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Postfix MTA-STS resolver daemon
+
+[Service]
+ExecStart=/usr/local/lib/postfix-mta-sts-resolver/bin/mta-sts-daemon
+Restart=always
+RestartSec=30
+
+[Install]
+WantedBy=multi-user.target

deploy-chatmail/src/deploy_chatmail/postfix/mta-sts-daemon.yml

@@ -0,0 +1,13 @@
+host: 127.0.0.1
+port: 8461
+reuse_port: true
+shutdown_timeout: 20
+cache:
+  type: internal
+  options:
+    cache_size: 10000
+proactive_policy_fetching:
+  enabled: true
+default_zone:
+  strict_testing: false
+  timeout: 4

scripts/bench.sh

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

scripts/generate-dns-zone.sh

@@ -0,0 +1,30 @@
+#!/bin/sh
+: ${CHATMAIL_DOMAIN:=c1.testrun.org}
+: ${CHATMAIL_SERVER:=$CHATMAIL_DOMAIN}
+: ${CHATMAIL_SSH:=$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 $CHATMAIL_SERVER.
+$CHATMAIL_DOMAIN. TXT "v=spf1 a:$CHATMAIL_SERVER -all"
+_dmarc.$CHATMAIL_DOMAIN. TXT "v=DMARC1;p=reject;rua=mailto:$EMAIL;ruf=mailto:$EMAIL;fo=1;adkim=r;aspf=r"
+_submission._tcp.$CHATMAIL_SERVER.  SRV 0 1 587 $CHATMAIL_SERVER.
+_submissions._tcp.$CHATMAIL_SERVER. SRV 0 1 465 $CHATMAIL_SERVER.
+_imap._tcp.$CHATMAIL_SERVER.        SRV 0 1 143 $CHATMAIL_SERVER.
+_imaps._tcp.$CHATMAIL_SERVER.       SRV 0 1 993 $CHATMAIL_SERVER.
+$CHATMAIL_DOMAIN. IN CAA 128 issue "letsencrypt.org;accounturi=$ACME_ACCOUNT_URL"
+_mta-sts.$CHATMAIL_DOMAIN. IN TXT "v=STSv1; id=$(date -u '+%Y%m%d%H%M')"
+mta-sts.$CHATMAIL_SERVER. IN CNAME $CHATMAIL_SERVER.
+_smtp._tls.$CHATMAIL_SERVER. IN TXT "v=TLSRPTv1;rua=mailto:$EMAIL"
+EOF
+if [ "$CHATMAIL_DOMAIN" != "$CHATMAIL_SERVER" ]; then
+cat <<EOF
+mta-sts.$CHATMAIL_DOMAIN. IN CNAME mta-sts.$CHATMAIL_SERVER.
+_smtp._tls.$CHATMAIL_DOMAIN. IN CNAME _smtp._tls.$CHATMAIL_SERVER.
+EOF
+fi
+$SSH opendkim-genzone -F | sed 's/^;.*$//;/^$/d'

scripts/test.sh

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

tests/chatmaild/test_dictproxy.py

@@ -1,53 +0,0 @@
-import os
-
-import pytest
-
-import chatmaild.dictproxy
-from chatmaild.dictproxy import get_user_data, lookup_passdb
-from chatmaild.database import Database, DBError
-
-
-@pytest.fixture()
-def db(tmpdir):
-    db_path = tmpdir / "passdb.sqlite"
-    print("database path:", db_path)
-    return Database(db_path)
-
-
-def test_basic(db):
-    chatmaild.dictproxy.NOCREATE_FILE = "/tmp/nocreate"
-    if os.path.exists(chatmaild.dictproxy.NOCREATE_FILE):
-        os.remove(chatmaild.dictproxy.NOCREATE_FILE)
-    lookup_passdb(db, "link2xt@c1.testrun.org", "asdf")
-    data = get_user_data(db, "link2xt@c1.testrun.org")
-    assert data
-
-
-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):
-    chatmaild.dictproxy.NOCREATE_FILE = "/tmp/nocreate"
-    with open(chatmaild.dictproxy.NOCREATE_FILE, "w+") as f:
-        f.write("")
-    assert os.path.exists(chatmaild.dictproxy.NOCREATE_FILE)
-    lookup_passdb(db, "newuser1@something.org", "kajdlqweqwe")
-    assert not get_user_data(db, "newuser1@something.org")
-    os.remove(chatmaild.dictproxy.NOCREATE_FILE)
-
-
-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()

tests/chatmaild/test_doveauth.py

@@ -0,0 +1,90 @@
+import json
+import sys
+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_different_accounts(db, gencreds):
+    num_threads = 100
+    req_per_thread = 5
+    results = queue.Queue()
+
+    def lookup(db):
+        for i in range(req_per_thread):
+            addr, password = gencreds()
+            try:
+                lookup_passdb(db, addr, password)
+            except Exception:
+                results.put(traceback.format_exc())
+            else:
+                results.put(None)
+
+    threads = []
+    for i in range(num_threads):
+        thread = threading.Thread(target=lookup, args=(db,), daemon=True)
+        threads.append(thread)
+
+    print(f"created {num_threads} threads, starting them and waiting for results")
+    for thread in threads:
+        thread.start()
+
+    for i in range(num_threads * req_per_thread):
+        res = results.get()
+        if res is not None:
+            pytest.fail(f"concurrent lookup failed\n{res}")

tests/conftest.py

@@ -9,9 +9,10 @@ import itertools
 from email.parser import BytesParser
 from email import policy
 from pathlib import Path
-from math import ceil
 import pytest
 
+from chatmaild.database import Database
+
 
 conftestdir = Path(__file__).parent
 
@@ -71,7 +72,7 @@ def pytest_report_header():
 
 @pytest.fixture
 def benchmark(request):
-    def bench(func, num, name=None):
+    def bench(func, num, name=None, reportfunc=None):
         if name is None:
             name = func.__name__
         durations = []
@@ -80,7 +81,7 @@ def benchmark(request):
             func()
             durations.append(time.time() - now)
         durations.sort()
-        request.config._benchresults[name] = durations
+        request.config._benchresults[name] = (reportfunc, durations)
 
     return bench
 
@@ -101,7 +102,9 @@ def pytest_terminal_summary(terminalreporter):
     headers = f"{'benchmark name': <30} " + fcol(float_names)
     tr.write_line(headers)
     tr.write_line("-" * len(headers))
-    for name, durations in results.items():
+    summary_lines = []
+
+    for name, (reportfunc, durations) in results.items():
         measures = [
             sorted(durations)[len(durations) // 2],
             min(durations),
@@ -110,6 +113,16 @@ def pytest_terminal_summary(terminalreporter):
         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
@@ -117,6 +130,16 @@ 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"
@@ -157,6 +180,16 @@ 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"
@@ -195,13 +228,20 @@ def gencreds(maildomain):
             num = next(count)
             alphanumeric = "abcdefghijklmnopqrstuvwxyz1234567890"
             user = "".join(random.choices(alphanumeric, k=10))
-            user = f"ac{num}_{user}"
-            password = "".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
@@ -272,7 +312,7 @@ class Remote:
         self.sshdomain = sshdomain
 
     def iter_output(self, logcmd=""):
-        getjournal = f"journalctl -f" if not logcmd else logcmd
+        getjournal = "journalctl -f" if not logcmd else logcmd
         self.popen = subprocess.Popen(
             ["ssh", f"root@{self.sshdomain}", getjournal],
             stdout=subprocess.PIPE,

tests/online/test_0_login.py

@@ -1,5 +1,6 @@
 import pytest
-import smtplib
+import threading
+import queue
 
 
 def test_login_basic_functioning(imap_or_smtp, gencreds, lp):
@@ -23,6 +24,11 @@ def test_login_basic_functioning(imap_or_smtp, gencreds, lp):
     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
@@ -35,3 +41,30 @@ def test_login_same_password(imap_or_smtp, gencreds):
     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_2_deltachat.py

@@ -91,7 +91,7 @@ class TestEndToEndDeltaChat:
 
         lp.sec("setup encrypted comms between ac1 and ac2 on different instances")
         qr = ac1.get_setup_contact_qr()
-        ch = ac2.qr_setup_contact(qr)
+        ac2.qr_setup_contact(qr)
         msg = ac2.wait_next_incoming_message()
         assert "verified" in msg.text
 

www/nine.testrun.org/index.html

@@ -0,0 +1,75 @@
+<!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: "Swansea", "Helvetica", sans-serif;
+            color: black;
+        }
+        a {
+            color: black;
+        }
+        h1, h2, h3 {
+            font-size: 18px;
+            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 and newcomers,</h1>
+            <p>
+                welcome to the first public "chat-mail instance",
+                a small and lean e-mail provider for smooth chatting.
+                Install Delta Chat or add an account:
+            <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>
+            <p>
+            <img class="section" src="collage-down.png" />
+
+            <h2>What's behind it, how does it operate?</h2>
+            <p>nine.testrun.org is run
+                by a small group of devs and sysadmins, reachable via root@.
+                They want to keep this instance running at least until end 2024.
+                Current limits:
+            <ul>
+            <li>Un-encrypted mails can not leave the chat-mail instance.</li>
+            <li>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.
+            </li>
+            <li>You may send up to 60 messages per minute.</li>
+            <li>Messages are unconditionally removed 40 days after arrival.</li>
+            <li>Max storage per user is 100MB.</li>
+            </ul>
+            <h2>Why are other email providers 1000 times more complicated?</h2>
+            <p>¯\_(ツ)_/¯</p>
+        </div>
+    </div>
+</body>
+</html>