nixos-mailserver/mail-server/dovecot.nix
Martin Weinelt 08f077c5ca Add support for LDAP users
Allow configuring lookups for users and their mail addresses from an
LDAP directory. The LDAP username will be used as an accountname as
opposed to the email address used as the `loginName` for declarative
accounts. Mailbox for LDAP users will be stored below
`/var/vmail/ldap/<account>`.

Configuring domains is out of scope, since domains require further
configuration within the NixOS mailserver construct to set up all
related services accordingly.

Aliases can already be configured using `mailserver.forwards` but could
be supported using LDAP at a later point.
2023-07-11 19:31:20 +00:00

390 lines
12 KiB
Nix

# nixos-mailserver: a simple mail server
# Copyright (C) 2016-2018 Robin Raymond
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>
{ config, pkgs, lib, ... }:
with (import ./common.nix { inherit config pkgs lib; });
let
cfg = config.mailserver;
passwdDir = "/run/dovecot2";
passdbFile = "${passwdDir}/passdb";
userdbFile = "${passwdDir}/userdb";
bool2int = x: if x then "1" else "0";
maildirLayoutAppendix = lib.optionalString cfg.useFsLayout ":LAYOUT=fs";
# maildir in format "/${domain}/${user}"
dovecotMaildir =
"maildir:${cfg.mailDirectory}/%d/%n${maildirLayoutAppendix}"
+ (lib.optionalString (cfg.indexDir != null)
":INDEX=${cfg.indexDir}/%d/%n"
);
postfixCfg = config.services.postfix;
dovecot2Cfg = config.services.dovecot2;
stateDir = "/var/lib/dovecot";
pipeBin = pkgs.stdenv.mkDerivation {
name = "pipe_bin";
src = ./dovecot/pipe_bin;
buildInputs = with pkgs; [ makeWrapper coreutils bash rspamd ];
buildCommand = ''
mkdir -p $out/pipe/bin
cp $src/* $out/pipe/bin/
chmod a+x $out/pipe/bin/*
patchShebangs $out/pipe/bin
for file in $out/pipe/bin/*; do
wrapProgram $file \
--set PATH "${pkgs.coreutils}/bin:${pkgs.rspamd}/bin"
done
'';
};
genPasswdScript = pkgs.writeScript "generate-password-file" ''
#!${pkgs.stdenv.shell}
set -euo pipefail
if (! test -d "${passwdDir}"); then
mkdir "${passwdDir}"
chmod 755 "${passwdDir}"
fi
for f in ${builtins.toString (lib.mapAttrsToList (name: value: passwordFiles."${name}") cfg.loginAccounts)}; do
if [ ! -f "$f" ]; then
echo "Expected password hash file $f does not exist!"
exit 1
fi
done
cat <<EOF > ${passdbFile}
${lib.concatStringsSep "\n" (lib.mapAttrsToList (name: value:
"${name}:${"$(head -n 1 ${passwordFiles."${name}"})"}::::::"
) cfg.loginAccounts)}
EOF
cat <<EOF > ${userdbFile}
${lib.concatStringsSep "\n" (lib.mapAttrsToList (name: value:
"${name}:::::::"
+ (if lib.isString value.quota
then "userdb_quota_rule=*:storage=${value.quota}"
else "")
) cfg.loginAccounts)}
EOF
chmod 600 ${passdbFile}
chmod 600 ${userdbFile}
'';
junkMailboxes = builtins.attrNames (lib.filterAttrs (n: v: v ? "specialUse" && v.specialUse == "Junk") cfg.mailboxes);
junkMailboxNumber = builtins.length junkMailboxes;
# The assertion garantees there is exactly one Junk mailbox.
junkMailboxName = if junkMailboxNumber == 1 then builtins.elemAt junkMailboxes 0 else "";
mkLdapSearchScope = scope: (
if scope == "sub" then "subtree"
else if scope == "one" then "onelevel"
else scope
);
in
{
config = with cfg; lib.mkIf enable {
assertions = [
{
assertion = junkMailboxNumber == 1;
message = "nixos-mailserver requires exactly one dovecot mailbox with the 'special use' flag set to 'Junk' (${builtins.toString junkMailboxNumber} have been found)";
}
];
# for sieve-test. Shelling it in on demand usually doesnt' work, as it reads
# the global config and tries to open shared libraries configured in there,
# which are usually not compatible.
environment.systemPackages = [
pkgs.dovecot_pigeonhole
];
services.dovecot2 = {
enable = true;
enableImap = enableImap || enableImapSsl;
enablePop3 = enablePop3 || enablePop3Ssl;
enablePAM = false;
enableQuota = true;
mailGroup = vmailGroupName;
mailUser = vmailUserName;
mailLocation = dovecotMaildir;
sslServerCert = certificatePath;
sslServerKey = keyPath;
enableLmtp = true;
modules = [ pkgs.dovecot_pigeonhole ] ++ (lib.optional cfg.fullTextSearch.enable pkgs.dovecot_fts_xapian );
mailPlugins.globally.enable = lib.optionals cfg.fullTextSearch.enable [ "fts" "fts_xapian" ];
protocols = lib.optional cfg.enableManageSieve "sieve";
sieveScripts = {
after = builtins.toFile "spam.sieve" ''
require "fileinto";
if header :is "X-Spam" "Yes" {
fileinto "${junkMailboxName}";
stop;
}
'';
};
mailboxes = cfg.mailboxes;
extraConfig = ''
#Extra Config
${lib.optionalString debug ''
mail_debug = yes
auth_debug = yes
verbose_ssl = yes
''}
${lib.optionalString (cfg.enableImap || cfg.enableImapSsl) ''
service imap-login {
inet_listener imap {
${if cfg.enableImap then ''
port = 143
'' else ''
# see https://dovecot.org/pipermail/dovecot/2010-March/047479.html
port = 0
''}
}
inet_listener imaps {
${if cfg.enableImapSsl then ''
port = 993
ssl = yes
'' else ''
# see https://dovecot.org/pipermail/dovecot/2010-March/047479.html
port = 0
''}
}
}
''}
${lib.optionalString (cfg.enablePop3 || cfg.enablePop3Ssl) ''
service pop3-login {
inet_listener pop3 {
${if cfg.enablePop3 then ''
port = 110
'' else ''
# see https://dovecot.org/pipermail/dovecot/2010-March/047479.html
port = 0
''}
}
inet_listener pop3s {
${if cfg.enablePop3Ssl then ''
port = 995
ssl = yes
'' else ''
# see https://dovecot.org/pipermail/dovecot/2010-March/047479.html
port = 0
''}
}
}
''}
protocol imap {
mail_max_userip_connections = ${toString cfg.maxConnectionsPerUser}
mail_plugins = $mail_plugins imap_sieve
}
protocol pop3 {
mail_max_userip_connections = ${toString cfg.maxConnectionsPerUser}
}
mail_access_groups = ${vmailGroupName}
ssl = required
ssl_min_protocol = TLSv1.2
ssl_prefer_server_ciphers = yes
service lmtp {
unix_listener dovecot-lmtp {
group = ${postfixCfg.group}
mode = 0600
user = ${postfixCfg.user}
}
}
recipient_delimiter = ${cfg.recipientDelimiter}
lmtp_save_to_detail_mailbox = ${cfg.lmtpSaveToDetailMailbox}
protocol lmtp {
mail_plugins = $mail_plugins sieve
}
passdb {
driver = passwd-file
args = ${passdbFile}
}
userdb {
driver = passwd-file
args = ${userdbFile}
default_fields = uid=${builtins.toString cfg.vmailUID} gid=${builtins.toString cfg.vmailUID} home=${cfg.mailDirectory}
}
${lib.optionalString cfg.ldap.enable ''
passdb {
driver = ldap
args = /etc/dovecot/dovecot-ldap.conf.ext
}
userdb {
driver = ldap
args = /etc/dovecot/dovecot-ldap.conf.ext
default_fields = home=/var/vmail/ldap/%u uid=${toString cfg.vmailUID} gid=${toString cfg.vmailUID}
}
''}
service auth {
unix_listener auth {
mode = 0660
user = ${postfixCfg.user}
group = ${postfixCfg.group}
}
}
auth_mechanisms = plain login
namespace inbox {
separator = ${cfg.hierarchySeparator}
inbox = yes
}
plugin {
sieve_plugins = sieve_imapsieve sieve_extprograms
sieve = file:${cfg.sieveDirectory}/%u/scripts;active=${cfg.sieveDirectory}/%u/active.sieve
sieve_default = file:${cfg.sieveDirectory}/%u/default.sieve
sieve_default_name = default
# From elsewhere to Spam folder
imapsieve_mailbox1_name = ${junkMailboxName}
imapsieve_mailbox1_causes = COPY,APPEND
imapsieve_mailbox1_before = file:${stateDir}/imap_sieve/report-spam.sieve
# From Spam folder to elsewhere
imapsieve_mailbox2_name = *
imapsieve_mailbox2_from = ${junkMailboxName}
imapsieve_mailbox2_causes = COPY
imapsieve_mailbox2_before = file:${stateDir}/imap_sieve/report-ham.sieve
sieve_pipe_bin_dir = ${pipeBin}/pipe/bin
sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.environment
}
${lib.optionalString cfg.fullTextSearch.enable ''
plugin {
plugin = fts fts_xapian
fts = xapian
fts_xapian = partial=${toString cfg.fullTextSearch.minSize} full=${toString cfg.fullTextSearch.maxSize} attachments=${bool2int cfg.fullTextSearch.indexAttachments} verbose=${bool2int cfg.debug}
fts_autoindex = ${if cfg.fullTextSearch.autoIndex then "yes" else "no"}
${lib.strings.concatImapStringsSep "\n" (n: x: "fts_autoindex_exclude${if n==1 then "" else toString n} = ${x}") cfg.fullTextSearch.autoIndexExclude}
fts_enforced = ${cfg.fullTextSearch.enforced}
}
${lib.optionalString (cfg.fullTextSearch.memoryLimit != null) ''
service indexer-worker {
vsz_limit = ${toString (cfg.fullTextSearch.memoryLimit*1024*1024)}
}
''}
''}
lda_mailbox_autosubscribe = yes
lda_mailbox_autocreate = yes
'';
};
environment.etc = lib.optionalAttrs (cfg.ldap.enable) {
"dovecot/dovecot-ldap.conf.ext" = {
mode = "0600";
uid = config.ids.uids.dovecot2;
gid = config.ids.gids.dovecot2;
text = ''
ldap_version = 3
uris = ${lib.concatStringsSep " " cfg.ldap.uris}
${lib.optionalString cfg.ldap.startTls ''
tls = yes
''}
tls_require_cert = hard
tls_ca_cert_file = ${cfg.ldap.tlsCAFile}
dn = ${cfg.ldap.bind.dn}
dnpass = ${cfg.ldap.bind.password}
sasl_bind = no
auth_bind = yes
base = ${cfg.ldap.searchBase}
scope = ${mkLdapSearchScope cfg.ldap.searchScope}
${lib.optionalString (cfg.ldap.dovecot.userAttrs != "") ''
user_attrs = ${cfg.ldap.dovecot.user_attrs}
''}
user_filter = ${cfg.ldap.dovecot.userFilter}
${lib.optionalString (cfg.ldap.dovecot.passAttrs != "") ''
pass_attrs = ${cfg.ldap.dovecot.passAttrs}
''}
pass_filter = ${cfg.ldap.dovecot.passFilter}
'';
};
};
systemd.services.dovecot2 = {
preStart = ''
${genPasswdScript}
rm -rf '${stateDir}/imap_sieve'
mkdir '${stateDir}/imap_sieve'
cp -p "${./dovecot/imap_sieve}"/*.sieve '${stateDir}/imap_sieve/'
for k in "${stateDir}/imap_sieve"/*.sieve ; do
${pkgs.dovecot_pigeonhole}/bin/sievec "$k"
done
chown -R '${dovecot2Cfg.mailUser}:${dovecot2Cfg.mailGroup}' '${stateDir}/imap_sieve'
'';
};
systemd.services.postfix.restartTriggers = [ genPasswdScript ];
systemd.services.dovecot-fts-xapian-optimize = lib.mkIf (cfg.fullTextSearch.enable && cfg.fullTextSearch.maintenance.enable) {
description = "Optimize dovecot indices for fts_xapian";
requisite = [ "dovecot2.service" ];
after = [ "dovecot2.service" ];
startAt = cfg.fullTextSearch.maintenance.onCalendar;
serviceConfig = {
Type = "oneshot";
ExecStart = "${pkgs.dovecot}/bin/doveadm fts optimize -A";
PrivateDevices = true;
PrivateNetwork = true;
ProtectKernelTunables = true;
ProtectKernelModules = true;
ProtectControlGroups = true;
ProtectHome = true;
ProtectSystem = true;
PrivateTmp = true;
};
};
systemd.timers.dovecot-fts-xapian-optimize = lib.mkIf (cfg.fullTextSearch.enable && cfg.fullTextSearch.maintenance.enable && cfg.fullTextSearch.maintenance.randomizedDelaySec != 0) {
timerConfig = {
RandomizedDelaySec = cfg.fullTextSearch.maintenance.randomizedDelaySec;
};
};
};
}