chore(update): use dovecot 2.3 built for Debian 13

.github/workflows/ci.yaml

@@ -29,7 +29,7 @@ jobs:
           ref: ${{ github.event.pull_request.head.sha }}
           persist-credentials: false
       - name: download filtermail
-        run: curl -L https://github.com/chatmail/filtermail/releases/download/v0.7.4/filtermail-x86_64 -o /usr/local/bin/filtermail && chmod +x /usr/local/bin/filtermail
+        run: curl -L https://github.com/chatmail/filtermail/releases/download/v0.7.0/filtermail-x86_64 -o /usr/local/bin/filtermail && chmod +x /usr/local/bin/filtermail
       - name: run chatmaild tests 
         working-directory: chatmaild
         run: pipx run tox

.github/workflows/docs-preview.yaml

@@ -51,7 +51,7 @@ jobs:
           mkdir -p "$HOME/.ssh"
           echo "${{ secrets.CHATMAIL_STAGING_SSHKEY }}" > "$HOME/.ssh/key"
           chmod 600 "$HOME/.ssh/key"
-          rsync -rILvh -e "ssh -i $HOME/.ssh/key -o StrictHostKeyChecking=no" $GITHUB_WORKSPACE/doc/build/ "${{ secrets.USERNAME }}@chatmail.at:${STEPS_PREPARE_OUTPUTS_PRID}/"
+          rsync -rILvh -e "ssh -i $HOME/.ssh/key -o StrictHostKeyChecking=no" $GITHUB_WORKSPACE/doc/build/ "${{ secrets.USERNAME }}@chatmail.at:/var/www/html/staging.chatmail.at/doc/relay/${STEPS_PREPARE_OUTPUTS_PRID}/"
         env:
           STEPS_PREPARE_OUTPUTS_PRID: ${{ steps.prepare.outputs.prid }}
 

.github/workflows/docs.yaml

@@ -47,5 +47,5 @@ jobs:
           mkdir -p "$HOME/.ssh"
           echo "${{ secrets.CHATMAIL_STAGING_SSHKEY }}" > "$HOME/.ssh/key"
           chmod 600 "$HOME/.ssh/key"
-          rsync -rILvh -e "ssh -i $HOME/.ssh/key -o StrictHostKeyChecking=no" $GITHUB_WORKSPACE/doc/build/ "${{ secrets.USERNAME }}@chatmail.at:"
+          rsync -rILvh -e "ssh -i $HOME/.ssh/key -o StrictHostKeyChecking=no" $GITHUB_WORKSPACE/doc/build/ "${{ secrets.USERNAME }}@chatmail.at:/var/www/html/chatmail.at/doc/relay/"
 

CHANGELOG.md

@@ -1,60 +1,5 @@
 # Changelog for chatmail deployment
 
-## [1.12.0] - 2026-07-31
-
-### Breaking Changes
-
-- [**breaking**] Introduce configurable system limits to reject new address creation and limit imap/smtp connections.
-  Dovecot default connection limit lowered from 50k to 10k,
-  Postfix default connection limit lowered from 5k to 1k,
-  larger relays need to adjust their settings.
-
-### Features
-
-- Reduce maximal_queue_lifetime from 5d to 2d
-- Disable negative cache in unbound (#992)
-- *(mtail)* Add incoming_mailer_daemon_mail_count
-- *(postfix)* Disable processing of MIME headers
-- *(dovecot)* Advertise privacy_mail as admin contact, drop server comment
-
-### Bug Fixes
-
-- Set relay restrictions per smtpd service with default reject
-- Reduce maxproc for filtermail-transport LMTP client to 500
-- Core 2.50.0 does not have delete_server_after config anymore.
-- Check if all required ports are available for filtermail (#983)
-- Always deploy unbound.conf.d/chatmail.conf (#993)
-- Expire empty directories (#994)
-- Crypt-r dependency was declared for wrong Python version
-- Always overwrite /etc/resolv.conf, even if it is a symbolic link
-- Pass kwargs to files.put()
-- List Iroh proxy endpoints used by 0.35 and 1.0, drop stale /relay/probe from earlier versions
-- Fix port discovery when ss -tulpn shows dovecot before stats
-
-### Documentation
-
-- Add scripts/initenv.sh to upgrade instructions
-- Update overview diagrams (#995)
-- *(overview)* Remove mermaid styles from 'Accepting and delivering mail' (#1009)
-- *(README.md)* Clarify security enforcement (#1011)
-
-### Miscellaneous Tasks
-
-- *(ci)* Auto-trigger docker build on release tag push
-- *(acmetool)* Update let's encrypt ToS link to 1.8
-- *(ci)* Update doc staging upload path
-- *(ci)* Fix docs upload path
-
-### Refactor
-
-- *(postfix)* Remove unused "filter" lmtp service
-- Install dns-root-data instead of using unbound-anchor
-- *(deps)* Remove domain-validator dependency
-
-### Testing
-
-- Set socket security for IMAP and SMTP to "TLS" in "dclogin"
-
 ## [1.11.0] - 2026-05-15
 
 ### Breaking Changes

CONTRIBUTING.md

@@ -5,6 +5,3 @@ We use [git-cliff] to generate the changelog from commit messages before the rel
 
 [Conventional Commits]: https://www.conventionalcommits.org/
 [git-cliff]: https://git-cliff.org/
-
-To update client app version information,
-edit [chatmaild/src/chatmaild/defaults/appversions.json](chatmaild/src/chatmaild/defaults/appversions.json).

README.md

@@ -8,12 +8,7 @@ Chatmail relay servers are interoperable Mail Transport Agents (MTAs) designed f
 -  **Instant/Realtime:** sub-second message delivery, realtime P2P
    streaming, privacy-preserving Push Notifications for Apple, Google, and Huawei;
 
--  **Security Enforcement**: Only connections with strict TLS are accepted;
+-  **Security Enforcement**: only strict TLS, DKIM and OpenPGP with minimized metadata accepted
-   all messages must be correctly signed with DKIM and OpenPGP-encrypted with minimized metadata.
-   There are experimental exceptions for no-DNS relays,
-   which are allowed use self-signed TLS certificates
-   and which do not need to DKIM-sign their messages.
-   Unencrypted messages are allowed in neither case.
 
 -  **Reliable Federation and Decentralization:** No spam or IP reputation checks, federating
    depends on established IETF standards and protocols.

RELEASE.md

@@ -1,13 +1,15 @@
 # Releasing a new version of chatmail relay
 
-For example, to release version 1.13.0 of chatmail relay, do the following steps.
+For example, to release version 1.9.0 of chatmail relay, do the following steps.
 
-1. Update the changelog: `git cliff --unreleased --tag 1.13.0 --prepend CHANGELOG.md` or `git cliff -u -t 1.13.0 -p CHANGELOG.md`.
+1. Update the changelog: `git cliff --unreleased --tag 1.9.0 --prepend CHANGELOG.md` or `git cliff -u -t 1.9.0 -p CHANGELOG.md`.
 
 2. Open the changelog in the editor, edit it if required.
 
 3. Commit the changes to the changelog with a commit message `chore(release): prepare for 1.9.0`.
 
-4. Open a PR with the new commit, merge it to main after review.
+3. Tag the release: `git tag --annotate 1.9.0`.
 
-5. In the web interface, create a GitHub release, tell it to create a new tag.
+4. Push the release tag: `git push origin 1.9.0`.
+
+5. Create a GitHub release: `gh release create 1.9.0`.

chatmaild/MANIFEST.in

@@ -1,4 +1,3 @@
-include src/chatmaild/defaults/*.json
 include src/chatmaild/ini/*.ini.f
 include src/chatmaild/ini/*.ini
 include src/chatmaild/tests/mail-data/*

chatmaild/pyproject.toml

@@ -8,9 +8,9 @@ version = "0.3"
 dependencies = [
   "iniconfig",
   "filelock",
-  "psutil",
   "requests",
-  "crypt-r >= 3.13.1 ; python_version >= '3.13'",
+  "crypt-r >= 3.13.1 ; python_version >= '3.11'",
+  "domain-validator",
 ]
 
 [tool.setuptools]

chatmaild/src/chatmaild/config.py

@@ -2,6 +2,7 @@ import ipaddress
 from pathlib import Path
 
 import iniconfig
+from domain_validator import DomainValidator
 
 from chatmaild.user import User
 
@@ -24,6 +25,7 @@ class Config:
             self.mail_domain = f"[{raw_domain}]"
             self.postfix_myhostname = ipaddress.IPv4Address(raw_domain).reverse_pointer
         else:
+            DomainValidator().validate_domain_re(raw_domain)
             self.ipv4_relay = None
             self.mail_domain = raw_domain
             self.postfix_myhostname = raw_domain
@@ -75,16 +77,6 @@ class Config:
         self.privacy_pdo = params.pop("privacy_pdo", None)
         self.privacy_supervisor = params.pop("privacy_supervisor", None)
 
-        self.max_load_1m = float(params.pop("max_load_1m", 5))
-        self.min_available_memory_mb = parse_size_mb(
-            params.pop("min_available_memory", "200M")
-        )
-        self.min_free_disk_space_mb = parse_size_mb(
-            params.pop("min_free_disk_space", "1G")
-        )
-        self.max_imap_connections = int(params.pop("max_imap_connections", 10000))
-        self.max_smtp_connections = int(params.pop("max_smtp_connections", 1000))
-
         # TLS certificate management.
         # If tls_external_cert_and_key is set, use externally managed certs.
         # Otherwise derived from the domain name:

chatmaild/src/chatmaild/defaults/appversions.json

@@ -1,15 +0,0 @@
-{
-  "clients": [
-    {
-      "clientId": "deltachat",
-      "sources": [
-        {
-          "sourceId": "gplay",
-          "versionInteger": 754,
-          "versionString": "2.57.0",
-          "downloadUrl": "https://github.com/deltachat/deltachat-android/releases/download/v2.57.0/deltachat-gplay-release-2.57.0.apk"
-        }
-      ]
-    }
-  ]
-}

chatmaild/src/chatmaild/doveauth.py

@@ -14,7 +14,6 @@ except ImportError:
 from .config import Config, read_config
 from .dictproxy import DictProxy
 from .migrate_db import migrate_from_db_to_maildir
-from .syslimits import has_sufficient_resources
 
 NOCREATE_FILE = "/etc/chatmail-nocreate"
 VALID_LOCALPART_RE = re.compile(r"^[a-z0-9._-]+$")
@@ -148,8 +147,6 @@ class AuthDictProxy(DictProxy):
             return userdata
         if not is_allowed_to_create(self.config, addr, cleartext_password):
             return
-        if not has_sufficient_resources(self.config):
-            return
 
         lock = filelock.FileLock(str(user.password_path) + ".lock", timeout=5)
         with lock:

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

@@ -42,33 +42,6 @@ mail_domain = {mail_domain}
 # minimum length a password must have
 #password_min_length = 9
 
-#
-# System resource limits
-#
-
-# The following three limits refuse creation of new addresses
-# while existing addresses keep working.
-# Rejections are logged by the doveauth service.
-
-# Maximum 1-minute load average, as reported by "uptime";
-# it counts processes waiting for disk I/O as well as for CPU.
-#max_load_1m = 5
-
-# Minimum memory available without swapping.
-#min_available_memory = 200M
-
-# Minimum free disk space on the file system holding the mailboxes.
-#min_free_disk_space = 1G
-
-# Maximum number of concurrent IMAP connections
-# (the Dovecot imap process limit).
-#max_imap_connections = 10000
-
-# Maximum number of concurrent SMTP connections
-# on each of the submission and smtps ports (the Postfix process limit).
-# A single client IP may use up to a fifth of this.
-#max_smtp_connections = 1000
-
 # 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.

chatmaild/src/chatmaild/metadata.py

@@ -1,10 +1,8 @@
-import json
 import logging
 import socket
 import sys
 import time
 from contextlib import contextmanager
-from importlib.resources import files
 
 from .config import read_config
 from .dictproxy import DictProxy
@@ -20,18 +18,6 @@ def turn_credentials(turn_socket_path):
             return file.readline().decode("utf-8").strip()
 
 
-def read_appversions(path):
-    try:
-        data = json.loads(path.read_bytes())
-    except FileNotFoundError:
-        return None
-    except (OSError, ValueError):
-        logging.exception(f"failed to read {path}")
-        return None
-    # the dict protocol is line-based, keep the value single-line
-    return json.dumps(data, separators=(",", ":"))
-
-
 def _is_valid_token_timestamp(timestamp, now):
     # Token if invalid after 90 days
     # or if the timestamp is in the future.
@@ -115,7 +101,6 @@ class MetadataDictProxy(DictProxy):
         self.iroh_relay = iroh_relay
         self.turn_hostname = turn_hostname
         self.turn_socket_path = turn_socket_path
-        self.appversions_path = files(__package__).joinpath("defaults/appversions.json")
 
     def handle_lookup(self, parts):
         # Lpriv/43f5f508a7ea0366dff30200c15250e3/devicetoken\tlkj123poi@c2.testrun.org
@@ -140,9 +125,6 @@ class MetadataDictProxy(DictProxy):
                         case "maxsmtprecipients":
                             # postfix default  (see "postconf smtpd_recipient_limit")
                             return "O1000\n"
-                        case "appversions":
-                            value = read_appversions(self.appversions_path)
-                            return f"O{value}\n" if value else "N\n"
 
         logging.warning(f"lookup ignored: {parts!r}")
         return "N\n"

chatmaild/src/chatmaild/syslimits.py

@@ -1,32 +0,0 @@
-"""Detect whether the system is at its limits."""
-
-import logging
-
-import psutil
-
-MB = 1024 * 1024
-
-
-def read_value(getter):
-    try:
-        return getter()
-    except Exception as e:
-        logging.warning("ignoring unreadable system limit: %s", e)
-        return None
-
-
-def has_sufficient_resources(config):
-    """Return False if load, memory or disk exceeds a configured limit."""
-    load = read_value(lambda: psutil.getloadavg()[0])
-    mem = read_value(lambda: psutil.virtual_memory().available // MB)
-    disk = read_value(lambda: psutil.disk_usage(str(config.mailboxes_dir)).free // MB)
-    if load is not None and load > config.max_load_1m:
-        msg = f"load avg {load:.2f} > {config.max_load_1m:.2f}"
-    elif mem is not None and mem < config.min_available_memory_mb:
-        msg = f"available memory {mem}MB < {config.min_available_memory_mb}MB"
-    elif disk is not None and disk < config.min_free_disk_space_mb:
-        msg = f"free disk {disk}MB < {config.min_free_disk_space_mb}MB"
-    else:
-        return True
-    logging.warning("registration rejected: %s", msg)
-    return False

chatmaild/src/chatmaild/tests/plugin.py

@@ -20,10 +20,6 @@ def make_config(tmp_path):
         basedir.mkdir(parents=True, exist_ok=True)
         overrides = settings.copy() if settings else {}
         overrides["mailboxes_dir"] = str(basedir)
-        # permissive resource limits so tests never depend on host load/memory/disk
-        overrides.setdefault("max_load_1m", "99999")
-        overrides.setdefault("min_available_memory", "0")
-        overrides.setdefault("min_free_disk_space", "0")
         write_initial_config(inipath, mail_domain, overrides=overrides)
         return read_config(inipath)
 

chatmaild/src/chatmaild/tests/test_appversions.py

@@ -1,96 +0,0 @@
-import json
-
-import pytest
-
-from chatmaild.metadata import MetadataDictProxy
-
-ALLOWED_URL_PREFIXES = (
-    "https://github.com/deltachat/",
-    "https://download.delta.chat/",
-)
-
-
-def check_string(value):
-    assert isinstance(value, str), value
-    assert value
-
-
-def check_version_integer(value):
-    # core parses this as u32, see https://github.com/chatmail/core/pull/8557
-    assert isinstance(value, int) and not isinstance(value, bool), value
-    assert 0 <= value < 2**32, value
-
-
-def check_appversions(data):
-    """Verifies the file the way core parses it.
-
-    core deserializes into typed structs and drops the whole payload
-    of a relay if a single value has an unexpected type,
-    while missing or misspelled keys silently turn into defaults.
-    """
-    assert set(data) == {"clients"}, data
-    assert isinstance(data["clients"], list)
-    assert data["clients"]
-    client_ids = []
-    for client in data["clients"]:
-        assert set(client) == {"clientId", "sources"}, client
-        check_string(client["clientId"])
-        client_ids.append(client["clientId"])
-        assert isinstance(client["sources"], list)
-        assert client["sources"]
-        source_ids = []
-        for source in client["sources"]:
-            assert set(source) == {
-                "sourceId",
-                "versionInteger",
-                "versionString",
-                "downloadUrl",
-            }, source
-            check_string(source["sourceId"])
-            source_ids.append(source["sourceId"])
-            check_version_integer(source["versionInteger"])
-            check_string(source["versionString"])
-            check_string(source["downloadUrl"])
-            assert source["downloadUrl"].startswith(ALLOWED_URL_PREFIXES)
-        # core takes the first matching source, later duplicates never surface
-        assert len(set(source_ids)) == len(source_ids), source_ids
-    assert len(set(client_ids)) == len(client_ids), client_ids
-
-
-@pytest.fixture
-def appversions():
-    # check the file which chatmail-metadata actually serves
-    path = MetadataDictProxy(notifier=None, metadata=None).appversions_path
-    return json.loads(path.read_text())
-
-
-def test_appversions_schema(appversions):
-    check_appversions(appversions)
-
-
-@pytest.mark.parametrize("value", [True, -1, 2**32, "754", 754.0, None])
-def test_version_integer_rejected(appversions, value):
-    appversions["clients"][0]["sources"][0]["versionInteger"] = value
-    with pytest.raises(AssertionError):
-        check_appversions(appversions)
-
-
-@pytest.mark.parametrize("key", ["clientId", "sources"])
-def test_misspelled_client_key_rejected(appversions, key):
-    client = appversions["clients"][0]
-    client[key + "s"] = client.pop(key)
-    with pytest.raises(AssertionError):
-        check_appversions(appversions)
-
-
-def test_duplicate_source_id_rejected(appversions):
-    sources = appversions["clients"][0]["sources"]
-    sources.append(dict(sources[0]))
-    with pytest.raises(AssertionError):
-        check_appversions(appversions)
-
-
-def test_foreign_download_url_rejected(appversions):
-    appversions["clients"][0]["sources"][0]["downloadUrl"] = "https://example.org/x.apk"
-    with pytest.raises(AssertionError):
-        check_appversions(appversions)

chatmaild/src/chatmaild/tests/test_config.py

@@ -45,8 +45,6 @@ def test_read_config_basic_using_defaults(tmp_path, maildomain):
     assert example_config.username_min_length == 9
     assert example_config.username_max_length == 9
     assert example_config.password_min_length == 9
-    assert example_config.max_imap_connections == 10000
-    assert example_config.max_smtp_connections == 1000
     assert example_config._unused_keys == []
 
 

chatmaild/src/chatmaild/tests/test_doveauth.py

@@ -202,17 +202,3 @@ def test_50_concurrent_lookups_different_accounts(gencreds, dictproxy):
         res = results.get()
         if res is not None:
             pytest.fail(f"concurrent lookup failed\n{res}")
-
-
-def test_insufficient_resources_block_creation_not_existing_logins(
-    dictproxy, gencreds, monkeypatch
-):
-    addr, password = gencreds()
-    assert dictproxy.lookup_passdb(addr, password)
-
-    monkeypatch.setattr(
-        chatmaild.doveauth, "has_sufficient_resources", lambda config: False
-    )
-    newaddr, newpassword = gencreds()
-    assert not dictproxy.lookup_passdb(newaddr, newpassword)
-    assert dictproxy.lookup_passdb(addr, password)

chatmaild/src/chatmaild/tests/test_metadata.py

@@ -1,5 +1,4 @@
 import io
-import json
 import time
 
 import pytest
@@ -8,7 +7,6 @@ import requests
 from chatmaild.metadata import (
     Metadata,
     MetadataDictProxy,
-    read_appversions,
 )
 from chatmaild.notifier import (
     Notifier,
@@ -371,32 +369,6 @@ def test_iroh_relay(dictproxy):
     assert wfile.getvalue() == b"Ohttps://example.org/\n"
 
 
-def test_read_appversions(tmp_path):
-    path = tmp_path.joinpath("appversions.json")
-    assert read_appversions(path) is None
-
-    path.write_text('{\n  "clients": []\n}')
-    assert read_appversions(path) == '{"clients":[]}'
-
-    # the value travels as a single dict protocol line
-    path.write_text('{"clients": [{"clientId": "one\\ntwo"}]}')
-    assert read_appversions(path) == '{"clients":[{"clientId":"one\\ntwo"}]}'
-
-    path.write_text("bad json")
-    assert read_appversions(path) is None
-
-
-def test_appversions_lookup(dictproxy):
-    # the version information shipped with chatmaild is served as a single line
-    key = b"Lshared/0123/vendor/vendor.dovecot/pvt/server/vendor/deltachat/appversions"
-    key += b"\tuser@example.org"
-    rfile, wfile = io.BytesIO(b"H\n" + key), io.BytesIO()
-    dictproxy.loop_forever(rfile, wfile)
-    value = wfile.getvalue()
-    assert value.startswith(b"O") and value.endswith(b"\n")
-    assert json.loads(value[1:])["clients"]
-
-
 def test_legacy_token_migration(metadata, testaddr):
     with metadata.get_metadata_dict(testaddr).modify() as data:
         data[metadata.DEVICETOKEN_KEY] = ["oldtoken1", "oldtoken2"]

chatmaild/src/chatmaild/tests/test_syslimits.py

@@ -1,45 +0,0 @@
-import shutil
-
-import psutil
-
-from chatmaild.syslimits import has_sufficient_resources
-
-PERMISSIVE = {
-    "max_load_1m": "99999",
-    "min_available_memory": "0",
-    "min_free_disk_space": "0",
-}
-
-
-def test_rejects_constrained_system(make_config, caplog):
-    assert has_sufficient_resources(make_config("chat.example.org", PERMISSIVE))
-    for settings in (
-        {"max_load_1m": "-1.0"},
-        {"min_available_memory": "99999999G"},
-        {"min_free_disk_space": "99999999G"},
-    ):
-        config = make_config("chat.example.org", PERMISSIVE | settings)
-        caplog.clear()
-        assert not has_sufficient_resources(config), settings
-        assert "registration rejected" in caplog.text
-
-
-def test_unreadable_disk_does_not_reject(make_config, caplog):
-    config = make_config(
-        "chat.example.org", PERMISSIVE | {"min_free_disk_space": "99999999G"}
-    )
-    shutil.rmtree(config.mailboxes_dir)
-    assert has_sufficient_resources(config)
-    assert "ignoring" in caplog.text
-
-
-def test_one_unreadable_value_keeps_other_checks(make_config, monkeypatch, caplog):
-    def raise_error(*args):
-        raise psutil.Error("dud")
-
-    monkeypatch.setattr(psutil, "getloadavg", raise_error)
-    config = make_config(
-        "chat.example.org", PERMISSIVE | {"min_free_disk_space": "99999999G"}
-    )
-    assert not has_sufficient_resources(config)
-    assert "ignoring" in caplog.text

cmdeploy/src/cmdeploy/acmetool/response-file.yaml.j2

@@ -1,2 +1,2 @@
 "acme-enter-email": "{{ email }}"
-"acme-agreement:https://letsencrypt.org/documents/LE-SA-v1.8-July-06-2026.pdf": true
+"acme-agreement:https://letsencrypt.org/documents/LE-SA-v1.6-August-18-2025.pdf": true

cmdeploy/src/cmdeploy/basedeploy.py

@@ -166,7 +166,7 @@ class Deployer:
             return self.put_template(src, dest, **kwargs)
         return self.put_file(src, dest)
 
-    def put_file(self, src, dest, mode="644", **kwargs):
+    def put_file(self, src, dest, mode="644"):
         if isinstance(src, str):
             src = get_resource(src)
         res = files.put(
@@ -176,7 +176,6 @@ class Deployer:
             user="root",
             group="root",
             mode=mode,
-            **kwargs,
         )
 
         return self._update_restart_signals(dest, res)

cmdeploy/src/cmdeploy/deployers.py

@@ -138,22 +138,9 @@ class UnboundDeployer(Deployer):
         # On an IPv4-only system, if unbound is started but not configured,
         # it causes subsequent steps to fail to resolve hosts.
         with blocked_service_startup():
-            # dns-root-data is an optional package
-            # that contains /usr/share/dns/root.key
-            #
-            # This file is copied into /var/lib/unbound/root.key
-            # at the start of "unbound" systemd unit
-            # by /usr/libexec/unbound-helper shell script
-            # from the "unbound" package as of version 1.17.1-2+deb12u4
-            #
-            # The same /var/lib/unbound/root.key can be retrieved directly
-            # following the procedure from
-            # <https://www.rfc-editor.org/info/rfc7958/#section-3.1>
-            # with "unbound-anchor -a /var/lib/unbound/root.key"
-            # We don't install and use "unbound-anchor".
             apt.packages(
                 name="Install unbound",
-                packages=["unbound", "dns-root-data", "dnsutils"],
+                packages=["unbound", "unbound-anchor", "dnsutils"],
             )
 
     def configure(self):
@@ -177,7 +164,12 @@ class UnboundDeployer(Deployer):
         self.put_file(
             src=BytesIO(b"nameserver 127.0.0.1\nnameserver 9.9.9.9\n"),
             dest="/etc/resolv.conf",
-            force=True,
+        )
+        server.shell(
+            name="Generate root keys for validating DNSSEC",
+            commands=[
+                "unbound-anchor -a /var/lib/unbound/root.key || true",
+            ],
         )
         self.ensure_directory(
             path="/etc/unbound/unbound.conf.d",
@@ -253,13 +245,6 @@ class LegacyRemoveDeployer(Deployer):
     def install(self):
         apt.packages(name="Remove rspamd", packages="rspamd", present=False)
 
-        # unbound-anchor was used to download /var/lib/unbound/root.key
-        # It is replaced by dns-root-data which contains /usr/share/dns/root.key.
-        # unbound systemd unit copies /usr/share/dns/root.key
-        # into /var/lib/unbound/root.key automatically on start
-        # as long as /usr/share/dns/root.key is present.
-        apt.packages(name="Remove unbound-anchor", packages="unbound-anchor", present=False)
-
         # remove historic expunge script
         # which is now implemented through a systemd timer (chatmail-expire)
         self.remove_file("/etc/cron.d/expunge")
@@ -370,8 +355,6 @@ class ChatmailVenvDeployer(Deployer):
     def __init__(self, config):
         self.config = config
         self.units = (
-            # doveauth must restart when chatmaild/ini file changes
-            "doveauth",
             "chatmail-metadata",
             "lastlogin",
             "chatmail-expire",
@@ -520,10 +503,10 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
             ("nginx", 443),
             (["master", "smtpd"], 465),
             (["master", "smtpd"], 587),
-            (["dovecot", "imap-login"], 993),
+            (["imap-login", "dovecot"], 993),
             ("iroh-relay", 3340),
             ("mtail", 3903),
-            (["dovecot", "stats"], 3904),
+            ("stats", 3904),
             ("nginx", 8443),
             (["master", "smtpd"], config.postfix_reinject_port),
             (["master", "smtpd"], config.postfix_reinject_port_incoming),

cmdeploy/src/cmdeploy/dovecot/deployer.py

@@ -19,12 +19,12 @@ DOVECOT_ARCHIVE_VERSION = "2.3.21+dfsg1-3"
 DOVECOT_PACKAGE_VERSION = f"1:{DOVECOT_ARCHIVE_VERSION}"
 
 DOVECOT_SHA256 = {
-    ("core", "amd64"): "dd060706f52a306fa863d874717210b9fe10536c824afe1790eec247ded5b27d",
+    ("core", "amd64"): "b24dcb26eee8fe2f769290fe4cdb665df3a017811eae972840c54dbc74936aad",
-    ("core", "arm64"): "e7548e8a82929722e973629ecc40fcfa886894cef3db88f23535149e7f730dc9",
+    ("core", "arm64"): "42afe5e00e136c8f8513a2c321a29566811a0c8805aeca4302252604f00e3433",
-    ("imapd", "amd64"): "8d8dc6fc00bbb6cdb25d345844f41ce2f1c53f764b79a838eb2a03103eebfa86",
+    ("imapd", "amd64"): "d13c486e7e19c68f316bae4836d9e94db54892a6eb56260d0d2914aa4babe1b6",
-    ("imapd", "arm64"): "178fa877ddd5df9930e8308b518f4b07df10e759050725f8217a0c1fb3fd707f",
+    ("imapd", "arm64"): "537840c4a3d7cdd529ce611481dd38c7ee41246fb8a678d9abeb4fd843f0f88d",
-    ("lmtpd", "amd64"): "2f69ba5e35363de50962d42cccbfe4ed8495265044e244007d7ccddad77513ab",
+    ("lmtpd", "amd64"): "2dd43f8860ee2152b0dffe5e29104add8d6134d9bccf10a21ab1b369b8aa0490",
-    ("lmtpd", "arm64"): "89f52fb36524f5877a177dff4a713ba771fd3f91f22ed0af7238d495e143b38f",
+    ("lmtpd", "arm64"): "ed26f31fe52eb8cb2104aa877c919443670a0ae42aa832eccc3f70bc497291ba",
 }
 
 
@@ -34,7 +34,7 @@ class DovecotDeployer(Deployer):
     def __init__(self, config, disable_mail):
         self.config = config
         self.disable_mail = disable_mail
-        self.units = []
+        self.units = ["doveauth"]
 
     def install(self):
         arch = host.get_fact(Arch)
@@ -119,7 +119,7 @@ def _download_dovecot_package(package: str, arch: str) -> tuple[str | None, bool
 
     url_version = DOVECOT_ARCHIVE_VERSION.replace("+", "%2B")
     deb_base = f"{pkg_name}_{url_version}_{arch}.deb"
-    primary_url = f"https://download.delta.chat/dovecot/{deb_base}"
+    primary_url = f"https://download.delta.chat/dovecot/staging-matrix-trixie-trixie/{deb_base}"
     fallback_url = f"https://github.com/chatmail/dovecot/releases/download/upstream%2F{url_version}/{deb_base}"
     url = _pick_url(primary_url, fallback_url)
     deb_filename = f"/root/{deb_base}"

cmdeploy/src/cmdeploy/dovecot/dovecot.conf.j2

@@ -37,15 +37,11 @@ default_client_limit = 20000
 # the following warning will be logged:
 #   Warning: service(imap): process_limit (1024) reached, client connections are being dropped
 service imap {
-  process_limit = {{ config.max_imap_connections }}
+  process_limit = 50000
 }
 
-{% if config.privacy_mail %}
+mail_server_admin = mailto:root@{{ config.mail_domain }}
-# Advertised to clients as IMAP METADATA /shared/admin (RFC 5464).
+mail_server_comment = Chatmail server
-# The privacy_mail contact from chatmail.ini is used because it is
-# the only address set by an operator.
-mail_server_admin = mailto:{{ config.privacy_mail }}
-{% endif %}
 
 # `zlib` enables compressing messages stored in the maildir.
 # See

cmdeploy/src/cmdeploy/filtermail/deployer.py

@@ -20,10 +20,10 @@ class FiltermailDeployer(Deployer):
             return
 
         arch = host.get_fact(facts.server.Arch)
-        url = f"https://github.com/chatmail/filtermail/releases/download/v0.7.4/filtermail-{arch}"
+        url = f"https://github.com/chatmail/filtermail/releases/download/v0.7.0/filtermail-{arch}"
         sha256sum = {
-            "x86_64": "484cb8dff083134aefba9fce4a6b7ef4784a0f0e28e5108ecf8bb9e58a44fd2c",
+            "x86_64": "451f295a85b3b12dbb0f89e18ec319f742ee46dec218f20f7923bfb017a248bd",
-            "aarch64": "66aa0ca2ca9add7a12d92883d76f8786384092adfde24a3d3a1d0b1f30d23a9e",
+            "aarch64": "6833061b2a2028264fdeb32f0a6123e1ff73de57dace125364016300b748452e",
         }[arch]
         self.download_executable(url, self.bin_path, sha256sum)
 

cmdeploy/src/cmdeploy/mtail/delivered_mail.mtail

@@ -28,13 +28,6 @@ counter created_nonci_accounts
   }
 }
 
-# doveauth refusing new addresses because a chatmail.ini
-# system resource limit is exceeded.
-counter rejected_registrations
-/registration rejected: / {
-  rejected_registrations++
-}
-
 counter postfix_timeouts
 /timeout after DATA/ {
   postfix_timeouts++
@@ -80,11 +73,6 @@ counter incoming_unencrypted_mail_count
   filtered_incoming_mail_count++
 }
 
-counter incoming_mailer_daemon_mail_count
-/Incoming: Filtering mailer-daemon message from/ {
-  incoming_mailer_daemon_mail_count++
-  filtered_incoming_mail_count++
-}
 
 counter rejected_unencrypted_mail_count
 /Rejected unencrypted mail/ {

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

@@ -128,10 +128,7 @@ http {
                         proxy_set_header Connection "upgrade";
                 }
 
-		# Endpoints Iroh uses for net_report probes and that clients
+		location /relay/probe {
-		# probe to tell whether this relay works. Both paths are served
-		# by iroh-relay 0.35 and by the 1.0 line.
-		location /ping {
                         proxy_pass http://127.0.0.1:3340;
                         proxy_http_version 1.1;
 		}

cmdeploy/src/cmdeploy/postfix/lmtp_header_cleanup

@@ -1,3 +1,23 @@
-/^DKIM-Signature:/            IGNORE
+# List of headers for incoming messages 
-/^Authentication-Results:/            IGNORE
+# that must be retained for functionality and compatibility reasons 
-/^Received:/            IGNORE
+/^From:/            DUNNO
+/^Message-Id:/      DUNNO
+/^Chat-/            DUNNO
+/^Content-Type:/    DUNNO
+
+# For receiving clear-text messages (still supported in May 2026)
+/^Subject:/         DUNNO
+/^Date:/            DUNNO
+/^To:/              DUNNO
+/^CC:/              DUNNO
+/^References:/      DUNNO
+/^In-Reply-To:/     DUNNO
+
+# Senders might support Autocrypt 1 but not RFC9788 (Header Protection) 
+/^Autocrypt:/       DUNNO
+
+# SecureJoin V2 protocol headers (for backward compatibility) 
+/^Secure-Join/      DUNNO
+
+# Ignore all other headers
+/.*/                IGNORE

cmdeploy/src/cmdeploy/postfix/main.cf.j2

@@ -85,14 +85,6 @@ inet_protocols = all
 
 lmtp_header_checks = regexp:/etc/postfix/lmtp_header_cleanup
 
-# Do not apply header checks to MIME headers
-# and other headers that are actually part of the message body.
-# Reference:
-# <https://www.postfix.org/postconf.5.html#disable_mime_input_processing>
-# <https://www.postfix.org/header_checks.5.html>
-# <https://stump.io/blog/2020/11/29/a-little-gotcha-with-postfixs-header_checks/>
-disable_mime_input_processing = yes
-
 mua_client_restrictions = permit_sasl_authenticated, reject
 mua_sender_restrictions = reject_sender_login_mismatch, permit_sasl_authenticated, reject
 mua_helo_restrictions = permit_mynetworks, reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname, permit

cmdeploy/src/cmdeploy/postfix/master.cf.j2

@@ -18,7 +18,7 @@ smtp      inet  n       -       y       -       -       smtpd
   -o smtpd_tls_mandatory_protocols=>=TLSv1.2
   -o smtpd_proxy_filter=127.0.0.1:{{ config.filtermail_smtp_port_incoming }}
   -o smtpd_relay_restrictions=reject_unauth_destination
-submission inet n       -       y       -       {{ config.max_smtp_connections }}    smtpd
+submission inet n       -       y       -       5000    smtpd
   -o syslog_name=postfix/submission
   -o smtpd_tls_security_level=encrypt
   -o smtpd_tls_mandatory_protocols=>=TLSv1.3
@@ -32,9 +32,9 @@ submission inet n       -       y       -       {{ config.max_smtp_connections }
   -o smtpd_sender_restrictions=$mua_sender_restrictions
   -o smtpd_recipient_restrictions=
   -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-  -o smtpd_client_connection_count_limit={{ config.max_smtp_connections // 5 }}
+  -o smtpd_client_connection_count_limit=1000
   -o smtpd_proxy_filter=127.0.0.1:{{ config.filtermail_smtp_port }}
-smtps     inet  n       -       y       -       {{ config.max_smtp_connections }}    smtpd
+smtps     inet  n       -       y       -       5000    smtpd
   -o syslog_name=postfix/smtps
   -o smtpd_tls_wrappermode=yes
   -o smtpd_tls_security_level=encrypt
@@ -48,7 +48,7 @@ smtps     inet  n       -       y       -       {{ config.max_smtp_connections }
   -o smtpd_sender_restrictions=$mua_sender_restrictions
   -o smtpd_recipient_restrictions=
   -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-  -o smtpd_client_connection_count_limit={{ config.max_smtp_connections // 5 }}
+  -o smtpd_client_connection_count_limit=1000
   -o smtpd_proxy_filter=127.0.0.1:{{ config.filtermail_smtp_port }}
 #628       inet  n       -       y       -       -       qmqpd
 pickup    unix  n       -       y       60      1       pickup
@@ -76,6 +76,7 @@ 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 outgoing filtered mail.
 127.0.0.1:{{ config.postfix_reinject_port }} inet  n       -       n       -       100      smtpd
   -o syslog_name=postfix/reinject

cmdeploy/src/cmdeploy/tests/online/test_2_deltachat.py

@@ -1,12 +1,10 @@
 import ipaddress
-import json
 import re
 import time
 
 import imap_tools
 import pytest
 import requests
-from chatmaild.tests.test_appversions import check_appversions
 
 from cmdeploy.cmdeploy import get_sshexec
 from cmdeploy.remote import rshell
@@ -53,17 +51,6 @@ class TestMetadataTokens:
         assert res == b"1111 2222"
         assert b"Getmetadata completed" in client.readline()
 
-    def test_get_appversions(self, imap_mailbox):
-        "get app version information shipped with the relay"
-        client = imap_mailbox.client
-        client.send(b'a01 GETMETADATA "" /shared/vendor/deltachat/appversions\n')
-        res = client.readline()
-        assert res[:1] == b"*"
-        res = client.readline().strip().rstrip(b")")
-        # the served value is a single line and passes the shipped file's schema
-        check_appversions(json.loads(res))
-        assert b"Getmetadata completed" in client.readline()
-
 
 class TestEndToEndDeltaChat:
     "Tests that use Delta Chat accounts on the chat mail instance."

cmdeploy/src/cmdeploy/tests/plugin.py

@@ -10,11 +10,13 @@ from pathlib import Path
 
 import pytest
 from chatmaild.config import is_valid_ipv4, read_config
+from domain_validator import DomainValidator
 
 
 def format_mail_domain(raw_domain: str) -> str:
     if is_valid_ipv4(raw_domain):
         return f"[{raw_domain}]"
+    DomainValidator().validate_domain_re(raw_domain)
     return raw_domain
 
 

doc/source/conf.py

@@ -22,12 +22,6 @@ extensions = [
 templates_path = ['_templates']
 exclude_patterns = []
 
-linkcheck_ignore = [
-    # only resolves once the file is merged to main
-    r"https://github\.com/chatmail/relay/blob/main/chatmaild/src/chatmaild/defaults/appversions\.json",
-]
-
-
 
 
 # -- Options for HTML output -------------------------------------------------

doc/source/getting_started.rst

@@ -199,93 +199,6 @@ creating addresses, login with ssh to the deployment machine and run:
 Chatmail address creation will be denied while this file is present.
 
 
-.. _system-limits:
-
-Configurable System Limits
---------------------------
-
-Limits for auto-rejecting address creation
-..........................................
-
-A relay refuses creation of new addresses
-when the machine runs low on resources,
-but existing addresses keep working.
-
-Three ``chatmail.ini`` settings control this,
-shown here with their defaults::
-
-    max_load_1m = 5
-    min_available_memory = 200M
-    min_free_disk_space = 1G
-
-- ``max_load_1m`` is the maximum 1-minute load average,
-  as reported by ``uptime``;
-  it counts processes waiting for disk I/O as well as for CPU.
-  It is deliberately not scaled by the number of CPUs
-  because I/O rather than CPU is what typically limits a relay.
-
-- ``min_available_memory`` is the minimum memory available without swapping.
-
-- ``min_free_disk_space`` is the minimum free disk space
-  on the file system holding the mailboxes.
-
-The defaults suit the small machine described in
-`Minimal requirements and prerequisites`_.
-
-.. note::
-
-   If you run a bigger machine,
-   raise ``max_load_1m`` after watching ``uptime`` under typical load.
-
-Rejections are logged by the ``doveauth`` service,
-so you can check whether a limit is set too tightly::
-
-    journalctl -u doveauth --grep 'registration rejected'
-
-If ``mtail_address`` is set, rejections are also counted
-in the ``rejected_registrations`` metric.
-
-
-Overall IMAP and SMTP connection limits
-.......................................
-
-Two further settings bound how many connections
-the relay accepts at all, again shown with their defaults::
-
-    max_imap_connections = 10000
-    max_smtp_connections = 1000
-
-``max_imap_connections`` becomes the Dovecot imap process limit,
-and ``max_smtp_connections`` the Postfix process limit
-on each of the submission and smtps ports.
-A single client IP may use up to a fifth of ``max_smtp_connections``.
-Each connection costs memory,
-so these limits defend the relay against running out of RAM.
-
-Unless ``imap_compress`` is enabled,
-an IMAP connection that is idle for ``imap_hibernate_timeout``
-is handed over to the ``imap-hibernate`` process
-and does not count towards ``max_imap_connections``,
-which is why a relay can serve far more IMAP clients
-than this setting suggests.
-
-If you run a large relay with 10k or 100k's of addresses,
-check current connection counts before upgrading
-and set the limits accordingly.
-
-To see how close a running relay is to these two limits,
-copy ``scripts/check-connections.sh`` from the relay repository
-onto the relay and run it there::
-
-    imap             5  ports 143,993   (max_imap_connections)
-                     5  dovecot sessions, 0 of them in an active imap process
-    submission       0  ports 465,587   (max_smtp_connections per port)
-    incoming         0  port 25         (from other relays, no chatmail.ini limit)
-
-It counts established sockets with ``ss``
-and cross-checks the IMAP number against ``doveadm who``.
-
-
 Running a relay with self-signed certificates
 ----------------------------------------------
 

doc/source/overview.rst

@@ -225,6 +225,21 @@ Accepting and delivering mail
         nginx -.SMTP inet:465.-> smtpd-smtps
         mta2[Remote relay] -.SMTP inet:25.-> smtpd-smtp
         mta2 -.HTTPS /mxdeliv.-> nginx
+        style postfix fill:#363
+        style qmgr fill:#252
+        style authclean fill:#252
+        style cleanup fill:#252
+        style lmtp-filtermail fill:#252
+        style lmtp fill:#252
+        style bounce fill:#252
+        style smtpd-submission fill:#252
+        style smtpd-smtps fill:#252
+        style smtpd-reinject-outgoing fill:#252
+        style smtpd-reinject-incoming fill:#252
+        style smtpd-smtp fill:#252
+        style filtermail-outgoing fill:#225
+        style filtermail-incoming fill:#225
+        style filtermail-transport fill:#225
 
 Operational details of a chatmail relay
 ----------------------------------------
@@ -249,33 +264,6 @@ Fresh chatmail addresses have a mailbox directory that contains:
    directories will typically be empty unless the user of that address
    hasn’t been online for a while.
 
-App version information (experimental)
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-A chatmail relay ships the
-`appversions.json <https://github.com/chatmail/relay/blob/main/chatmaild/src/chatmaild/defaults/appversions.json>`_
-file of the ``chatmaild`` package
-and serves its content under the IMAP METADATA key
-``/shared/vendor/deltachat/appversions``.
-Chat apps installed outside of app stores read this key
-to learn about updates and where to download them.
-The mechanism is experimental and may change.
-
-The file travels with the normal deploy:
-update the repository checkout and run ``cmdeploy run``.
-Local modifications of ``appversions.json`` are deployed as-is,
-so you can serve your own app version information,
-including links to app downloads.
-There is no automatic refresh:
-version information changes only when you deploy again.
-
-.. note::
-
-   Note that as of August 2026, only Delta Chat Android Google Play version
-   is beginning to support discovering app versions from relays.
-   Generally, consumers of relay-provided app version information
-   need to verify themselves that downloaded app files are valid.
-
 Active ports
 ~~~~~~~~~~~~
 

scripts/check-connections.sh

@@ -1,26 +0,0 @@
-#!/bin/bash
-#
-# Show current IMAP and SMTP connections on a chatmail relay,
-# to compare against the max_imap_connections and max_smtp_connections
-# settings in chatmail.ini.  Run this on the relay itself.
-set -e
-
-# Count established TCP connections whose local port is one of the arguments.
-established() {
-    filter=$(printf 'sport = :%s or ' "$@")
-    ss -Htn state established "( ${filter% or } )" | wc -l
-}
-
-# doveadm prints a header line and then one line per logged-in user,
-# with that user's number of connections in the second column.
-sessions=$(doveadm who | awk 'NR > 1 { n += $2 } END { print n + 0 }')
-
-# Unless imap_compress is enabled, connections idle for
-# imap_hibernate_timeout are handed over to the imap-hibernate
-# process, so they cost no imap process while idle.
-active=$(pgrep -x imap | wc -l)
-
-printf 'imap        %6d  ports 143,993   (max_imap_connections)\n' "$(established 143 993)"
-printf '            %6d  dovecot sessions, %d of them in an active imap process\n' "$sessions" "$active"
-printf 'submission  %6d  ports 465,587   (max_smtp_connections per port)\n' "$(established 465 587)"
-printf 'incoming    %6d  port 25         (from other relays, no chatmail.ini limit)\n' "$(established 25)"