Merge remote-tracking branch 'origin/hpk/tls-external' into j4n/docker-traefik

.github/workflows/test-tls-external.yaml

@@ -0,0 +1,37 @@
+name: test tls_external_cert_and_key on staging2.testrun.org
+
+on:
+  workflow_run:
+    workflows:
+      - "deploy on staging2.testrun.org, and run tests"
+    types:
+      - completed
+
+jobs:
+  test-tls-external:
+    name: test tls_external_cert_and_key
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    concurrency: staging2.testrun.org
+    environment:
+      name: staging2.testrun.org
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: prepare SSH
+        run: |
+          mkdir -p ~/.ssh
+          echo "${{ secrets.STAGING_SSH_KEY }}" >> ~/.ssh/id_ed25519
+          chmod 600 ~/.ssh/id_ed25519
+          ssh-keyscan staging2.testrun.org >> ~/.ssh/known_hosts 2>/dev/null
+
+      - run: scripts/initenv.sh
+
+      - name: append venv/bin to PATH
+        run: echo venv/bin >>$GITHUB_PATH
+
+      - name: run tls_external e2e test
+        run: |
+          python -m cmdeploy.tests.setup_tls_external \
+            staging2.testrun.org

chatmaild/src/chatmaild/config.py

@@ -61,10 +61,24 @@ class Config:
         self.privacy_pdo = params.get("privacy_pdo")
         self.privacy_supervisor = params.get("privacy_supervisor")
 
-        # TLS certificate management: derived from the domain name.
+        # TLS certificate management.
-        # Domains starting with "_" use self-signed certificates
+        # If tls_external_cert_and_key is set, use externally managed certs.
-        # All other domains use ACME.
+        # Otherwise derived from the domain name:
-        if self.mail_domain.startswith("_"):
+        # - Domains starting with "_" use self-signed certificates
+        # - All other domains use ACME.
+        external = params.get("tls_external_cert_and_key", "").strip()
+
+        if external:
+            parts = external.split()
+            if len(parts) != 2:
+                raise ValueError(
+                    "tls_external_cert_and_key must have two space-separated"
+                    " paths: CERT_PATH KEY_PATH"
+                )
+            self.tls_cert_mode = "external"
+            self.tls_cert_path = parts[0]
+            self.tls_key_path = parts[1]
+        elif self.mail_domain.startswith("_"):
             self.tls_cert_mode = "self"
             self.tls_cert_path = "/etc/ssl/certs/mailserver.pem"
             self.tls_key_path = "/etc/ssl/private/mailserver.key"

chatmaild/src/chatmaild/ini/chatmail.ini.f

@@ -48,6 +48,13 @@ passthrough_senders =
 # (space-separated, item may start with "@" to whitelist whole recipient domains)
 passthrough_recipients =
 
+# Use externally managed TLS certificates instead of built-in acmetool.
+# Paths refer to files on the deployment server (not the build machine).
+# Both files must already exist before running cmdeploy.
+# Certificate renewal is your responsibility; changed files are
+# picked up automatically by all relay services.
+# tls_external_cert_and_key = /path/to/fullchain.pem /path/to/privkey.pem
+
 # path to www directory - documented here: https://chatmail.at/doc/relay/getting_started.html#custom-web-pages
 #www_folder = www
 

chatmaild/src/chatmaild/tests/test_config.py

@@ -87,3 +87,36 @@ def test_config_tls_self(make_config):
     assert config.tls_cert_mode == "self"
     assert config.tls_cert_path == "/etc/ssl/certs/mailserver.pem"
     assert config.tls_key_path == "/etc/ssl/private/mailserver.key"
+
+
+def test_config_tls_external(make_config):
+    config = make_config(
+        "chat.example.org",
+        {
+            "tls_external_cert_and_key": "/custom/fullchain.pem /custom/privkey.pem",
+        },
+    )
+    assert config.tls_cert_mode == "external"
+    assert config.tls_cert_path == "/custom/fullchain.pem"
+    assert config.tls_key_path == "/custom/privkey.pem"
+
+
+def test_config_tls_external_overrides_underscore(make_config):
+    config = make_config(
+        "_test.example.org",
+        {
+            "tls_external_cert_and_key": "/certs/fullchain.pem /certs/privkey.pem",
+        },
+    )
+    assert config.tls_cert_mode == "external"
+    assert config.tls_cert_path == "/certs/fullchain.pem"
+
+
+def test_config_tls_external_bad_format(make_config):
+    with pytest.raises(ValueError, match="two space-separated"):
+        make_config(
+            "chat.example.org",
+            {
+                "tls_external_cert_and_key": "/only/one/path.pem",
+            },
+        )

cmdeploy/src/cmdeploy/deployers.py

@@ -20,7 +20,7 @@ from pyinfra.operations import apt, files, pip, server, systemd
 from cmdeploy.cmdeploy import Out
 
 from .acmetool import AcmetoolDeployer
-from .selfsigned.deployer import SelfSignedTlsDeployer
+from .external.deployer import ExternalTlsDeployer
 from .basedeploy import (
     Deployer,
     Deployment,
@@ -35,6 +35,7 @@ from .mtail.deployer import MtailDeployer
 from .nginx.deployer import NginxDeployer
 from .opendkim.deployer import OpendkimDeployer
 from .postfix.deployer import PostfixDeployer
+from .selfsigned.deployer import SelfSignedTlsDeployer
 from .www import build_webpages, find_merge_conflict, get_paths
 
 
@@ -540,6 +541,20 @@ class GithashDeployer(Deployer):
         )
 
 
+def get_tls_deployer(config, mail_domain):
+    """Select the appropriate TLS deployer based on config."""
+    tls_domains = [mail_domain, f"mta-sts.{mail_domain}", f"www.{mail_domain}"]
+
+    if config.tls_cert_mode == "acme":
+        return AcmetoolDeployer(config.acme_email, tls_domains)
+    elif config.tls_cert_mode == "self":
+        return SelfSignedTlsDeployer(mail_domain)
+    elif config.tls_cert_mode == "external":
+        return ExternalTlsDeployer(config.tls_cert_path, config.tls_key_path)
+    else:
+        raise ValueError(f"Unknown tls_cert_mode: {config.tls_cert_mode}")
+
+
 def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -> None:
     """Deploy a chat-mail instance.
 
@@ -604,12 +619,7 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
                     )
                     exit(1)
 
-    tls_domains = [mail_domain, f"mta-sts.{mail_domain}", f"www.{mail_domain}"]
+    tls_deployer = get_tls_deployer(config, mail_domain)
-
-    if config.tls_cert_mode == "acme":
-        tls_deployer = AcmetoolDeployer(config.acme_email, tls_domains)
-    else:
-        tls_deployer = SelfSignedTlsDeployer(mail_domain)
 
     all_deployers = [
         ChatmailDeployer(mail_domain),

cmdeploy/src/cmdeploy/external/deployer.py

@@ -0,0 +1,69 @@
+from pyinfra.operations import files, server, systemd
+
+from cmdeploy.basedeploy import Deployer, get_resource
+
+
+class ExternalTlsDeployer(Deployer):
+    """Expects TLS certificates to be managed on the server.
+
+    Validates that the configured certificate and key files
+    exist on the remote host.  Installs a systemd path unit
+    that watches the certificate file and automatically
+    restarts/reloads affected services when it changes.
+    """
+
+    def __init__(self, cert_path, key_path):
+        self.cert_path = cert_path
+        self.key_path = key_path
+
+    def configure(self):
+        server.shell(
+            name="Verify external TLS certificate and key exist",
+            commands=[
+                f"test -f {self.cert_path} && test -f {self.key_path}",
+            ],
+        )
+
+        # Deploy the .path unit (templated with the cert path).
+        source = get_resource("tls-cert-reload.path.f", pkg=__package__)
+        content = source.read_text().format(cert_path=self.cert_path).encode()
+
+        import io
+
+        path_unit = files.put(
+            name="Upload tls-cert-reload.path",
+            src=io.BytesIO(content),
+            dest="/etc/systemd/system/tls-cert-reload.path",
+            user="root",
+            group="root",
+            mode="644",
+        )
+
+        service_unit = files.put(
+            name="Upload tls-cert-reload.service",
+            src=get_resource("tls-cert-reload.service", pkg=__package__),
+            dest="/etc/systemd/system/tls-cert-reload.service",
+            user="root",
+            group="root",
+            mode="644",
+        )
+
+        if path_unit.changed or service_unit.changed:
+            self.need_restart = True
+
+    def activate(self):
+        systemd.service(
+            name="Enable tls-cert-reload path watcher",
+            service="tls-cert-reload.path",
+            running=True,
+            enabled=True,
+            restarted=self.need_restart,
+            daemon_reload=self.need_restart,
+        )
+        # Always trigger a reload so services pick up the current cert.
+        # The path unit handles future changes via inotify.
+        server.shell(
+            name="Reload TLS services for current certificate",
+            commands=["systemctl start tls-cert-reload.service"],
+        )
+

cmdeploy/src/cmdeploy/external/tls-cert-reload.path.f

@@ -0,0 +1,11 @@
+# Watch the TLS certificate file for changes.
+# When the cert is updated (e.g. renewed by an external process),
+# this triggers tls-cert-reload.service to restart the affected services.
+[Unit]
+Description=Watch TLS certificate for changes
+
+[Path]
+PathChanged={cert_path}
+
+[Install]
+WantedBy=multi-user.target

cmdeploy/src/cmdeploy/external/tls-cert-reload.service

@@ -0,0 +1,15 @@
+# Reload services that cache the TLS certificate.
+#
+# dovecot: caches the cert at startup; reload re-reads SSL certs
+#          without dropping existing connections.
+# nginx:   caches the cert at startup; reload gracefully picks up
+#          the new cert for new connections.
+# postfix: reads the cert fresh on each TLS handshake,
+#          does NOT need a reload/restart.
+[Unit]
+Description=Reload TLS services after certificate change
+
+[Service]
+Type=oneshot
+ExecStart=/bin/systemctl reload dovecot
+ExecStart=/bin/systemctl reload nginx

cmdeploy/src/cmdeploy/nginx/nginx.conf.j2

@@ -84,7 +84,7 @@ http {
 		}
 
 		location /new {
-{% if config.tls_cert_mode == "acme" %}
+{% if config.tls_cert_mode != "self" %}
 			if ($request_method = GET) {
 				# Redirect to Delta Chat,
 				# which will in turn do a POST request.
@@ -106,7 +106,7 @@ http {
 		#
 		# Redirects are only for browsers.
 		location /cgi-bin/newemail.py {
-{% if config.tls_cert_mode == "acme" %}
+{% if config.tls_cert_mode != "self" %}
 			if ($request_method = GET) {
 				return 301 dcaccount:https://{{ config.mail_domain }}/new;
 			}

cmdeploy/src/cmdeploy/selfsigned/deployer.py

@@ -1,8 +1,29 @@
-from pyinfra.operations import apt, files, server
+import shlex
+
+from pyinfra.operations import apt, server
 
 from cmdeploy.basedeploy import Deployer
 
 
+def openssl_selfsigned_args(domain, cert_path, key_path, days=36500):
+    """Return the openssl argument list for a self-signed certificate.
+
+    The certificate uses an EC P-256 key with SAN entries for *domain*,
+    ``www.<domain>`` and ``mta-sts.<domain>``.
+    """
+    return [
+        "openssl", "req", "-x509",
+        "-newkey", "ec", "-pkeyopt", "ec_paramgen_curve:P-256",
+        "-noenc", "-days", str(days),
+        "-keyout", str(key_path),
+        "-out", str(cert_path),
+        "-subj", f"/CN={domain}",
+        "-addext", "extendedKeyUsage=serverAuth,clientAuth",
+        "-addext",
+        f"subjectAltName=DNS:{domain},DNS:www.{domain},DNS:mta-sts.{domain}",
+    ]
+
+
 class SelfSignedTlsDeployer(Deployer):
     """Generates a self-signed TLS certificate for all chatmail endpoints."""
 
@@ -18,18 +39,13 @@ class SelfSignedTlsDeployer(Deployer):
         )
 
     def configure(self):
+        args = openssl_selfsigned_args(
+            self.mail_domain, self.cert_path, self.key_path,
+        )
+        cmd = shlex.join(args)
         server.shell(
             name="Generate self-signed TLS certificate if not present",
-            commands=[
+            commands=[f"[ -f {self.cert_path} ] || {cmd}"],
-                f"[ -f {self.cert_path} ] || openssl req -x509"
-                f" -newkey ec -pkeyopt ec_paramgen_curve:P-256"
-                f" -noenc -days 36500"
-                f" -keyout {self.key_path}"
-                f" -out {self.cert_path}"
-                f' -subj "/CN={self.mail_domain}"'
-                f' -addext "extendedKeyUsage=serverAuth,clientAuth"'
-                f' -addext "subjectAltName=DNS:{self.mail_domain},DNS:www.{self.mail_domain},DNS:mta-sts.{self.mail_domain}"',
-            ],
         )
 
     def activate(self):

cmdeploy/src/cmdeploy/tests/setup_tls_external.py

@@ -0,0 +1,362 @@
+"""Setup and verify external TLS certificates for a chatmail server.
+
+Generates a self-signed TLS certificate, uploads it to the chatmail
+server via SCP, runs ``cmdeploy run``, and then probes all TLS-enabled
+ports (nginx, postfix, dovecot) to verify the certificate is actually
+served.  After probing, checks remote service logs for errors.
+
+Prerequisites
+~~~~~~~~~~~~~
+- SSH root access to the target server (same as ``cmdeploy run``)
+- ``cmdeploy`` in PATH (activate the venv first)
+
+How to run
+~~~~~~~~~~
+From the repository root::
+
+    # Full run: generate cert, deploy, probe ports, check services
+    python -m cmdeploy.tests.setup_tls_external DOMAIN
+
+    # Re-probe only (after a previous deploy)
+    python -m cmdeploy.tests.setup_tls_external DOMAIN \\
+        --skip-deploy --skip-certgen
+
+    # Override SSH host (e.g. when domain doesn't resolve to the server)
+    python -m cmdeploy.tests.setup_tls_external DOMAIN \\
+        --ssh-host staging-ipv4.testrun.org
+
+Arguments
+~~~~~~~~~
+DOMAIN            mail domain for the chatmail server (SSH root login must work)
+
+Options
+~~~~~~~
+--skip-deploy     skip ``cmdeploy run``, only probe ports
+--skip-certgen    skip cert generation/upload, use certs already on server
+--ssh-host HOST   SSH host override (defaults to DOMAIN)
+"""
+
+import argparse
+import shutil
+import smtplib
+import socket
+import ssl
+import subprocess
+import sys
+import tempfile
+import time
+from pathlib import Path
+
+# Cert paths on the remote server
+REMOTE_CERT = "/etc/ssl/certs/tmp_fullchain.pem"
+REMOTE_KEY = "/etc/ssl/private/tmp_privkey.pem"
+
+
+# ---------------------------------------------------------------------------
+# Config generation
+# ---------------------------------------------------------------------------
+
+
+def generate_config(domain: str, config_dir: Path) -> Path:
+    """Generate a chatmail.ini with tls_external_cert_and_key for *domain*."""
+    from chatmaild.config import write_initial_config
+
+    ini_path = config_dir / "chatmail.ini"
+    write_initial_config(
+        ini_path,
+        domain,
+        overrides={
+            "tls_external_cert_and_key": f"{REMOTE_CERT} {REMOTE_KEY}",
+        },
+    )
+    print(f"[+] Generated chatmail.ini for {domain} in {config_dir}")
+    return ini_path
+
+
+# ---------------------------------------------------------------------------
+# Certificate generation
+# ---------------------------------------------------------------------------
+
+
+def generate_cert(domain: str, cert_dir: Path) -> tuple:
+    """Generate a self-signed TLS cert+key for *domain* with proper SANs."""
+    from cmdeploy.selfsigned.deployer import openssl_selfsigned_args
+
+    cert_path = cert_dir / "fullchain.pem"
+    key_path = cert_dir / "privkey.pem"
+    subprocess.check_call(openssl_selfsigned_args(domain, cert_path, key_path, days=30))
+    print(f"[+] Generated cert for {domain} in {cert_dir}")
+    return cert_path, key_path
+
+
+# ---------------------------------------------------------------------------
+# Upload certs to remote server
+# ---------------------------------------------------------------------------
+
+
+def upload_certs(
+    ssh_host: str,
+    cert_path: Path,
+    key_path: Path,
+) -> None:
+    """SCP cert and key to the remote server."""
+    subprocess.check_call([
+        "scp", str(cert_path), f"root@{ssh_host}:{REMOTE_CERT}",
+    ])
+    subprocess.check_call([
+        "scp", str(key_path), f"root@{ssh_host}:{REMOTE_KEY}",
+    ])
+    # Ensure cert is world-readable and key is readable by ssl-cert group
+    # (dovecot/postfix/nginx need to read these files)
+    subprocess.check_call([
+        "ssh", f"root@{ssh_host}",
+        f"chmod 644 {REMOTE_CERT} && chmod 640 {REMOTE_KEY}"
+        f" && chgrp ssl-cert {REMOTE_KEY}",
+    ])
+    print(f"[+] Uploaded cert/key to {ssh_host}")
+
+
+# ---------------------------------------------------------------------------
+# Deploy
+# ---------------------------------------------------------------------------
+
+
+def run_deploy(ini_path: str) -> None:
+    """Run ``cmdeploy run --skip-dns-check --config <ini>``."""
+    cmd = ["cmdeploy", "run", "--config", str(ini_path), "--skip-dns-check"]
+    print(f"[+] Running: {' '.join(cmd)}")
+    subprocess.check_call(cmd)
+    print("[+] Deploy completed successfully")
+
+
+# ---------------------------------------------------------------------------
+# TLS port probing
+# ---------------------------------------------------------------------------
+
+
+def get_peer_cert_binary(host: str, port: int) -> bytes:
+    """Connect to host:port with TLS and return the DER-encoded peer cert."""
+    ctx = ssl.create_default_context()
+    ctx.check_hostname = False
+    ctx.verify_mode = ssl.CERT_NONE
+    with socket.create_connection((host, port), timeout=15) as sock:
+        with ctx.wrap_socket(sock, server_hostname=host) as ssock:
+            return ssock.getpeercert(binary_form=True)
+
+
+def get_smtp_starttls_cert_binary(host: str, port: int = 587) -> bytes:
+    """Connect via SMTP STARTTLS and return the DER cert."""
+    ctx = ssl.create_default_context()
+    ctx.check_hostname = False
+    ctx.verify_mode = ssl.CERT_NONE
+    with smtplib.SMTP(host, port, timeout=15) as smtp:
+        smtp.starttls(context=ctx)
+        return smtp.sock.getpeercert(binary_form=True)
+
+
+def check_cert_matches(
+    label: str, served_der: bytes, expected_der: bytes,
+) -> bool:
+    """Compare served DER cert against the expected cert."""
+    if served_der == expected_der:
+        print(f"  [OK]   {label}: certificate matches")
+        return True
+    else:
+        print(f"  [FAIL] {label}: certificate does NOT match")
+        return False
+
+
+def load_cert_der(cert_pem_path: Path) -> bytes:
+    """Load a PEM cert file and return its DER encoding."""
+    pem_text = cert_pem_path.read_text()
+    start = pem_text.index("-----BEGIN CERTIFICATE-----")
+    end = pem_text.index("-----END CERTIFICATE-----") + len(
+        "-----END CERTIFICATE-----"
+    )
+    return ssl.PEM_cert_to_DER_cert(pem_text[start:end])
+
+
+def probe_all_ports(host: str, expected_cert_der: bytes) -> bool:
+    """Probe TLS ports and verify the served certificate matches.
+
+    Checks ports 993 (IMAP), 465 (SMTPS), 587 (STARTTLS), and 443
+    (nginx stream).  Port 8443 is skipped as nginx binds it to
+    localhost behind the stream proxy on 443.
+    """
+    print(f"\n[+] Probing TLS ports on {host}...")
+    all_ok = True
+
+    for label, port in [
+        ("IMAP/TLS (993)", 993),
+        ("SMTP/TLS (465)", 465),
+    ]:
+        try:
+            served = get_peer_cert_binary(host, port)
+            if not check_cert_matches(label, served, expected_cert_der):
+                all_ok = False
+        except Exception as e:
+            print(f"  [FAIL] {label}: connection failed: {e}")
+            all_ok = False
+
+    # STARTTLS on port 587
+    try:
+        served = get_smtp_starttls_cert_binary(host, 587)
+        if not check_cert_matches("SMTP/STARTTLS (587)", served, expected_cert_der):
+            all_ok = False
+    except Exception as e:
+        print(f"  [FAIL] SMTP/STARTTLS (587): connection failed: {e}")
+        all_ok = False
+
+    # Port 443 (nginx stream proxy with ALPN routing)
+    try:
+        served = get_peer_cert_binary(host, 443)
+        if not check_cert_matches("nginx/443 (stream)", served, expected_cert_der):
+            all_ok = False
+    except Exception as e:
+        print(f"  [FAIL] nginx/443 (stream): connection failed: {e}")
+        all_ok = False
+
+    return all_ok
+
+
+# ---------------------------------------------------------------------------
+# Post-deploy service health checks
+# ---------------------------------------------------------------------------
+
+SERVICES = ["dovecot", "postfix", "nginx"]
+
+
+def check_remote_services(ssh_host: str, since: str = "") -> bool:
+    """SSH to the server and check for service failures or errors.
+
+    *since* is a ``journalctl --since`` timestamp (e.g. ``"5 min ago"``).
+    If empty, checks the entire boot journal.
+    """
+    print(f"\n[+] Checking remote service health on {ssh_host}...")
+    all_ok = True
+
+    for svc in SERVICES:
+        try:
+            result = subprocess.run(
+                ["ssh", f"root@{ssh_host}",
+                 f"systemctl is-active {svc}.service"],
+                capture_output=True, text=True, timeout=15, check=False,
+            )
+            status = result.stdout.strip()
+            if status == "active":
+                print(f"  [OK]   {svc}: active")
+            else:
+                print(f"  [FAIL] {svc}: {status}")
+                all_ok = False
+        except Exception as e:
+            print(f"  [FAIL] {svc}: check failed: {e}")
+            all_ok = False
+
+    since_arg = f'--since="{since}"' if since else ""
+    print(f"\n[+] Checking journal for errors on {ssh_host}...")
+    for svc in SERVICES:
+        try:
+            result = subprocess.run(
+                ["ssh", f"root@{ssh_host}",
+                 f"journalctl -u {svc}.service {since_arg}"
+                 f" --no-pager -p err -q"],
+                capture_output=True, text=True, timeout=15, check=False,
+            )
+            errors = result.stdout.strip()
+            if errors:
+                print(f"  [WARN] {svc} errors in journal:")
+                for line in errors.splitlines()[:10]:
+                    print(f"         {line}")
+                all_ok = False
+            else:
+                print(f"  [OK]   {svc}: no errors in journal")
+        except Exception as e:
+            print(f"  [FAIL] {svc}: journal check failed: {e}")
+            all_ok = False
+
+    return all_ok
+
+
+# ---------------------------------------------------------------------------
+# Main
+# ---------------------------------------------------------------------------
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+    )
+    parser.add_argument(
+        "domain",
+        help="mail domain (SSH root login must work to this host)",
+    )
+    parser.add_argument(
+        "--skip-deploy",
+        action="store_true",
+        help="skip cmdeploy run, only probe ports",
+    )
+    parser.add_argument(
+        "--skip-certgen",
+        action="store_true",
+        help="skip cert generation and upload (use existing)",
+    )
+    parser.add_argument(
+        "--ssh-host",
+        help="SSH host override (defaults to DOMAIN)",
+    )
+    args = parser.parse_args()
+
+    domain = args.domain
+    ssh_host = args.ssh_host or domain
+    print(f"[+] Domain: {domain}")
+    print(f"[+] SSH host: {ssh_host}")
+    print(f"[+] Remote cert: {REMOTE_CERT}")
+    print(f"[+] Remote key:  {REMOTE_KEY}")
+
+    work_dir = Path(tempfile.mkdtemp(prefix="tls-external-test-"))
+    try:
+        # Generate chatmail.ini
+        ini_path = generate_config(domain, work_dir)
+
+        if not args.skip_certgen:
+            local_cert, local_key = generate_cert(domain, work_dir)
+            upload_certs(ssh_host, local_cert, local_key)
+        else:
+            local_cert = work_dir / "fullchain.pem"
+            subprocess.check_call([
+                "scp", f"root@{ssh_host}:{REMOTE_CERT}", str(local_cert),
+            ])
+
+        # Record timestamp before deploy for journal filtering
+        deploy_start = time.strftime("%Y-%m-%d %H:%M:%S")
+
+        if not args.skip_deploy:
+            run_deploy(ini_path)
+
+        # Probe TLS ports
+        expected_der = load_cert_der(local_cert)
+        ports_ok = probe_all_ports(domain, expected_der)
+
+        # Check service health (only errors since deploy started)
+        services_ok = check_remote_services(ssh_host, since=deploy_start)
+
+        if ports_ok and services_ok:
+            print(
+                "\n[SUCCESS] All TLS port probes passed and services are healthy"
+            )
+            return 0
+        else:
+            if not ports_ok:
+                print("\n[FAILURE] Some TLS port probes failed", file=sys.stderr)
+            if not services_ok:
+                print(
+                    "\n[FAILURE] Some services have errors", file=sys.stderr
+                )
+            return 1
+    finally:
+        shutil.rmtree(work_dir, ignore_errors=True)
+
+
+if __name__ == "__main__":
+    sys.exit(main())

cmdeploy/src/cmdeploy/tests/test_external_tls.py

@@ -0,0 +1,78 @@
+"""Functional tests for tls_external_cert_and_key option."""
+
+import json
+
+import chatmaild.newemail
+import pytest
+from chatmaild.config import read_config, write_initial_config
+
+
+def make_external_config(tmp_path, cert_key=None):
+    inipath = tmp_path / "chatmail.ini"
+    overrides = {}
+    if cert_key is not None:
+        overrides["tls_external_cert_and_key"] = cert_key
+    write_initial_config(inipath, "chat.example.org", overrides=overrides)
+    return inipath
+
+
+def test_external_tls_config_reads_paths(tmp_path):
+    inipath = make_external_config(
+        tmp_path,
+        cert_key=(
+            "/etc/letsencrypt/live/chat.example.org/fullchain.pem"
+            " /etc/letsencrypt/live/chat.example.org/privkey.pem"
+        ),
+    )
+    config = read_config(inipath)
+    assert config.tls_cert_mode == "external"
+    assert (
+        config.tls_cert_path == "/etc/letsencrypt/live/chat.example.org/fullchain.pem"
+    )
+    assert config.tls_key_path == "/etc/letsencrypt/live/chat.example.org/privkey.pem"
+
+
+def test_external_tls_missing_option_uses_acme(tmp_path):
+    config = read_config(make_external_config(tmp_path))
+    assert config.tls_cert_mode == "acme"
+
+
+def test_external_tls_bad_format_raises(tmp_path):
+    inipath = make_external_config(tmp_path, cert_key="/only/one/path.pem")
+    with pytest.raises(ValueError, match="two space-separated"):
+        read_config(inipath)
+
+
+def test_external_tls_three_paths_raises(tmp_path):
+    inipath = make_external_config(tmp_path, cert_key="/a /b /c")
+    with pytest.raises(ValueError, match="two space-separated"):
+        read_config(inipath)
+
+
+def test_external_tls_no_dclogin_url(tmp_path, capsys, monkeypatch):
+    inipath = make_external_config(
+        tmp_path, cert_key="/certs/fullchain.pem /certs/privkey.pem"
+    )
+    monkeypatch.setattr(chatmaild.newemail, "CONFIG_PATH", str(inipath))
+    chatmaild.newemail.print_new_account()
+    out, _ = capsys.readouterr()
+    lines = out.split("\n")
+    dic = json.loads(lines[2])
+    assert "dclogin_url" not in dic
+
+
+def test_external_tls_selects_correct_deployer(tmp_path):
+    from cmdeploy.deployers import get_tls_deployer
+    from cmdeploy.external.deployer import ExternalTlsDeployer
+    from cmdeploy.selfsigned.deployer import SelfSignedTlsDeployer
+
+    inipath = make_external_config(
+        tmp_path, cert_key="/certs/fullchain.pem /certs/privkey.pem"
+    )
+    config = read_config(inipath)
+    deployer = get_tls_deployer(config, "chat.example.org")
+
+    assert isinstance(deployer, ExternalTlsDeployer)
+    assert not isinstance(deployer, SelfSignedTlsDeployer)
+    assert deployer.cert_path == "/certs/fullchain.pem"
+    assert deployer.key_path == "/certs/privkey.pem"

doc/source/getting_started.rst

@@ -204,6 +204,40 @@ and all other relays will accept connections from it
 without requiring certificate verification.
 This is useful for experimental setups and testing.
 
+.. _external-tls:
+
+Running a relay with externally managed certificates
+-----------------------------------------------------
+
+If you already have a TLS certificate manager
+(e.g. Traefik, certbot, or another ACME client)
+running on the deployment server,
+you can configure the relay to use those certificates
+instead of the built-in ``acmetool``.
+
+Set the following in ``chatmail.ini``::
+
+    tls_external_cert_and_key = /path/to/fullchain.pem /path/to/privkey.pem
+
+The paths must point to certificate and key files
+on the deployment server.
+During ``cmdeploy run``, these paths are written into
+the Postfix, Dovecot, and Nginx configurations.
+No certificate files are transferred from the build machine —
+they must already exist on the server,
+managed by your external certificate tool.
+
+The deploy will verify that both files exist on the server.
+``acmetool`` is **not** installed or run in this mode.
+
+.. note::
+
+   You are responsible for certificate renewal.
+   When the certificate file changes on disk,
+   all relay services pick up the new certificate automatically
+   (via a systemd path watcher installed during deploy).
+
+
 Migrating to a new build machine
 ----------------------------------
 

doc/source/overview.rst

@@ -308,6 +308,11 @@ When providing a TLS certificate to your chatmail relay server, make
 sure to provide the full certificate chain and not just the last
 certificate.
 
+If you use an external certificate manager (e.g. Traefik or certbot),
+set ``tls_external_cert_and_key`` in ``chatmail.ini``
+to provide the certificate and key paths.
+See :ref:`external-tls` for details.
+
 If you are running an Exim server and don’t see incoming connections
 from a chatmail relay server in the logs, make sure ``smtp_no_mail`` log
 item is enabled in the config with ``log_selector = +smtp_no_mail``. By