install/logical/friot/postfix.nix

   1 {pkgs, lib, config, nodes, ...}:
   2 let inherit (builtins) attrNames toFile;
   3     inherit (lib) types;
   4     inherit (pkgs.lib) unlines unlinesAttrs;
   5     inherit (config.services) x509 postfix dovecot2 postgrey openldap;
   6     unwords = lib.concatStringsSep " ";
   7     when    = x: y: if x == null then "" else y;
   8
   9     submissionHeaderCleanupRules = pkgs.writeText "submission_header_cleanup_rules" ''
  10       # Removes sensitive headers from mails handed in via the submission or smtps port.
  11       # See https://thomas-leister.de/mailserver-debian-stretch/
  12       # Uses "pcre" style regex.
  13
  14       /^Received:/         IGNORE
  15       /^User-Agent:/       IGNORE
  16       /^X-Enigmail:/       IGNORE
  17       /^X-Mailer:/         IGNORE
  18       /^X-Originating-IP:/ IGNORE
  19     '';
  20 in
  21 {
  22 options.services.postfix.aliases = lib.mkOption {
  23   type    = with types; attrsOf (listOf str);
  24   default = {};
  25   example = { "root@${config.networking.domain}" = [
  26                 "user1@${config.networking.domain}"
  27                 "user2@${config.networking.domain}"
  28               ];
  29               "@example.coop" = ["user1@${config.networking.domain}"];
  30             };
  31 };
  32 config = {
  33   systemd.services.postfix.after =
  34     if x509.scheme == "letsencrypt"
  35     then [ "nginx.service" ] # XXX: not sure if this is enough
  36     else [];
  37   services.postfix = {
  38     enable = true;
  39     #hostname = config.networking.domain;
  40     #domain = "localdomain";
  41     networksStyle = "host";
  42     #mapFiles."valias" = toFile "valias" (unlines (all_valiases_postfix ++ catchAllPostfix));
  43     # See https://blog.grimneko.de/2011/12/24/a-bunch-of-tips-for-improving-your-postfix-setup/
  44     # for details on how this file looks. By using the same file as valias,
  45     # every alias is uniquely owned by its user.
  46     # The user's own address is already in all_valiases_postfix.
  47     #mapFiles."vaccounts" = toFile "vaccounts" (unlines all_valiases_postfix);
  48     mapFiles."virtual_alias_maps" =
  49       toFile "virtual_alias_maps"
  50        (unlinesAttrs (dom: {accounts, ...}:
  51          unlinesAttrs (user: acct:
  52            unlines (map (from: "${from} ${user}@${dom}") acct.aliases)
  53           ) accounts
  54         ) dovecot2.domains
  55        + "\n"
  56        + unlinesAttrs
  57           (from: to: "${from} ${unwords to}")
  58           postfix.aliases);
  59     mapFiles."ldap-virtual_alias_maps.cf" =
  60       toFile "ldap-virtual_alias_maps.cf" ''
  61         version          = 3
  62         debuglevel       = 3
  63         server_host      = ldapi://
  64         bind             = sasl
  65         sasl_mechs       = EXTERNAL
  66         search_base      = ou=posix,${openldap.domainSuffix}
  67         scope            = sub
  68         dereference      = 0
  69         query_filter     = (&(mail=%s))
  70         result_format    = %s
  71         result_attribute = mailAlias
  72       '';
  73     sslCert = x509.cert;
  74     sslKey = x509.key;
  75     #enableSubmission = true;
  76     #enableSmtp = true;
  77     destination = [
  78       "localhost"
  79       "localhost.localdomain"
  80       config.networking.hostName
  81       "${config.networking.hostName}.localdomain"
  82     ];
  83     networks = [
  84       "127.0.0.0/8"
  85       "[::1]/128"
  86     ];
  87     recipientDelimiter = "+";
  88     config = {
  89       # Appending .domain is the MUA's job
  90       append_dot_mydomain = false;
  91       # No console bell on new mail
  92       biff = false;
  93       body_checks = "";
  94       #content_filter = "amavisfeed:[127.0.0.1]:10024";
  95       #debug_peer_level = 4;
  96       #debug_peer_list = ".$myhostname";
  97       default_extra_recipient_limit = "5000";
  98       # Uncomment the next line to generate "delayed mail" warnings
  99       #delay_warning_time = "4h";
 100       # Stops some techniques used to harvest email addresses
 101       disable_vrfy_command = true;
 102       duplicate_filter_limit = "5000";
 103       enable_long_queue_ids = false;
 104       # Pass unexisting $mydestination recipients to dovecot
 105       fallback_transport = "lmtp:unix:private/dovecot-lmtp";
 106       forward_path = [
 107         ''$home/.forward''${recipient_delimiter}''${extension}''
 108         "$home/.forward"
 109       ];
 110       #header_checks = "regexp:/var/lib/postfix/conf/header_checks";
 111       #inet_interfaces = "all";
 112       line_length_limit = "2048";
 113
 114       # Let $fallback_transport check existence of recipients
 115       local_recipient_maps = "";
 116       #mail_spool_directory = "/var/spool/mail";
 117         # NOTE: nixpkgs's default
 118       #local_header_rewrite_clients = "";
 119       #home_mailbox = "Maildir/";
 120       #mailbox_command = ''
 121       #  ${pkgs.procmail}/bin/procmail -t -a "$SENDER" -a "$RECIPIENT" -a "$USER" -a "$EXTENSION" -a "$DOMAIN" -a "$ORIGINAL_RECIPIENT" "$HOME/.procmailrc"
 122       #'';
 123       mailbox_size_limit = "204800000";
 124
 125       masquerade_classes = [ "envelope_sender" "header_sender" "header_recipient" ];
 126       masquerade_domains = "";
 127       masquerade_exceptions = "root";
 128       maximal_queue_lifetime = "5d";
 129       message_size_limit = "20480000";
 130       mime_header_checks = "";
 131       milter_header_checks = "";
 132       nested_header_checks = "";
 133       non_smtpd_milters = "";
 134       parent_domain_matches_subdomains = [
 135         #"debug_peer_list"
 136         #"fast_flush_domains"
 137         #"mynetworks"
 138         #"permit_mx_backup_networks"
 139         #"qmqpd_authorized_clients"
 140         #"smtpd_access_maps"
 141       ];
 142       permit_mx_backup_networks = "";
 143       #policy-spf_time_limit = "3600s";
 144       propagate_unmatched_extensions = [ "canonical" "virtual" "alias" ];
 145       queue_minfree = "0";
 146       #receive_override_options = "no_address_mappings";
 147         # no_unknown_recipient_checks
 148         #         Do not try to reject unknown recipients (SMTP server only).
 149         #         This is typically specified AFTER an external content filter.
 150         # no_address_mappings
 151         #         Disable canonical address mapping, virtual alias map expansion,
 152         #         address masquerading, and automatic BCC (blind carbon-copy) recipients.
 153         #         This is typically specified BEFORE an external content filter (eg. amavis).
 154         # no_header_body_checks
 155         #         Disable header/body_checks. This is typically specified AFTER
 156         #         an external content filter.
 157         # no_milters
 158         #         Disable Milter (mail filter) applications.
 159         #         This is typically specified AFTER an external content filter.
 160       # Parse the extension in email address, eg. contact+extension@
 161       relayhost = "";
 162       #relay_clientcerts = hash:/var/lib/postfix/conf/relay_clientcerts
 163       # This is where to put backup MX domains
 164       relay_domains = "$mydestination";
 165       relay_recipient_maps = "";
 166       smtp_body_checks = "";
 167       #smtp_cname_overrides_servername = false;
 168       smtp_connect_timeout = "60s";
 169       #smtp_header_checks = "regexp:/var/lib/postfix/smtp_header_checks";
 170       smtp_mime_header_checks = "";
 171       smtp_nested_header_checks = "";
 172       smtp_tls_exclude_ciphers = [ "ADH" "MD5" "CAMELLIA" "SEED" "3DES" "DES" "RC4" "eNULL" "aNULL" ];
 173       #smtp_tls_fingerprint_digest = "sha1";
 174       smtp_tls_loglevel = "1";
 175       #smtp_tls_note_starttls_offer = true;
 176       #smtp_tls_policy_maps = "hash:/var/lib/postfix/conf/tls_policy";
 177       # Only allow TLSv* protocols
 178       smtp_tls_protocols = [ "!SSLv2" "!SSLv3" ];
 179       smtp_tls_scert_verifydepth = "5";
 180       #smtp_tls_secure_cert_match = [ "nexthop" "dot-nexthop" ];
 181       smtp_tls_security_level = "may";
 182       smtp_tls_session_cache_database = "btree:$data_directory/smtp_tls_session_cache";
 183       #smtp_tls_session_cache_timeout = "3600s";
 184       #smtp_tls_verify_cert_match = "hostname";
 185       # Useful to test restrictions
 186       smtpd_authorized_xclient_hosts = "127.0.0.1";
 187       smtpd_banner = "${config.networking.fqdn} ESMTP $mail_name (NixOS)";
 188       smtpd_client_connection_count_limit = "50";
 189       smtpd_client_connection_rate_limit = "0";
 190       smtpd_client_event_limit_exceptions = "$mynetworks";
 191       smtpd_client_message_rate_limit = "0";
 192       smtpd_client_new_tls_session_rate_limit = "0";
 193       smtpd_client_port_logging = false;
 194       smtpd_client_recipient_rate_limit = "0";
 195       smtpd_client_restrictions = [
 196         #"check_client_access hash:/var/lib/postfix/conf/client_blacklist"
 197       ];
 198       smtpd_data_restrictions = [
 199         "reject_unauth_pipelining"
 200           # Force the smtp client to wait OK before sending
 201         "permit"
 202       ];
 203       # Disable opportunistic encryption
 204       smtpd_discard_ehlo_keywords = "starttls";
 205       #smtpd_end_of_data_restrictions = "";
 206       # Ban 5 sec on error
 207       smtpd_error_sleep_time = "5";
 208       smtpd_helo_required = true;
 209       smtpd_helo_restrictions = [
 210         "reject_invalid_helo_hostname"
 211         "reject_non_fqdn_helo_hostname"
 212         #"reject_unknown_helo_hostname"
 213           # May be useful to fight spam
 214         "permit"
 215       ];
 216       #smtpd_milters = "";
 217       # Needed by postgrey
 218       smtpd_peername_lookup = true;
 219       smtpd_recipient_limit = "5000";
 220       smtpd_recipient_overshoot_limit = "5000";
 221       smtpd_recipient_restrictions = [
 222         "reject_non_fqdn_recipient"
 223         #"reject_invalid_hostname"
 224         "reject_unknown_recipient_domain"
 225         #"reject_non_fqdn_sender"
 226         "reject_unauth_pipelining"
 227         #"check_policy_service inet:localhost:12340"
 228         # check quota
 229         "permit_mynetworks"
 230         "permit_tls_clientcerts"
 231         "permit_sasl_authenticated"
 232         "reject_unverified_recipient"
 233           # $fallback_transport is responsible of checking the existence of the recipient
 234           # WARNING: verify(8) has a cache, dumpable if verify(8) is stopped, with:
 235           # postmap -s btree:/var/lib/postfix/data/verify_cache
 236         # Bypass SPF check and postgrey if the recipient is not for us or someone in backup_mx
 237         "reject_unauth_destination"
 238         # Check SPF
 239         #"check_policy_service unix:private/spfcheck"
 240         # Greylisting using postgrey
 241         "check_policy_service unix:${postgrey.socket.path}"
 242         # Once postgrey passed, permit what is for us
 243         "permit_auth_destination"
 244         "reject"
 245         #"reject_unknown_sender_domain"
 246           # Maybe better in smtpd_sender_restrictions
 247         #"reject_rbl_client bl.spamcop.net"
 248         #"reject_rbl_client list.dsbl.org"
 249         #"reject_rbl_client zen.spamhaus.org"
 250         #"reject_rbl_client dnsbl.sorbs.net"
 251       ];
 252       smtpd_relay_restrictions = [
 253         "permit_mynetworks"
 254         "permit_sasl_authenticated"
 255           # NOTE: permit auth through dovecot's SASL
 256         "reject_unauth_destination"
 257       ];
 258       #smtpd_restriction_classes = "";
 259       broken_sasl_auth_clients = false;
 260       #smtpd_sasl_auth_enable = true;
 261       #smtpd_sasl_path = "private/auth";
 262       #smtpd_sasl_security_options = "noanonymous";
 263       #smtpd_sasl_type = "dovecot";
 264       smtpd_sender_restrictions = [
 265         "permit_mynetworks"
 266         "permit_tls_clientcerts"
 267         "permit_sasl_authenticated"
 268           # NOTE: permit auth through dovecot's SASL
 269         #"check_sender_access hash:/var/lib/postfix/conf/sender_access"
 270         "reject_unauth_pipelining"
 271         "reject_non_fqdn_sender"
 272         #"reject_sender_login_mismatch"
 273         #"reject_unknown_sender_domain"
 274         "permit"
 275       ];
 276       smtpd_starttls_timeout = "300s";
 277       #smtpd_tls_always_issue_session_ids = true;
 278       # No SASL AUTH without TLS
 279       smtpd_tls_auth_only = true;
 280       #smtpd_tls_CApath = "/etc/postfix/x509/ca/";
 281       smtpd_tls_ask_ccert = false;
 282       #smtpd_tls_ccert_verifydepth = "5";
 283       smtpd_tls_ciphers = "high";
 284       smtpd_tls_eecdh_grade = "ultra";
 285       # Disable weak ciphers as reported by https://ssl-tools.net
 286       # https://serverfault.com/questions/744168/how-to-disable-rc4-on-postfix
 287       smtpd_tls_exclude_ciphers = [ "RC4" "aNULL" ];
 288       smtpd_tls_fingerprint_digest = "sha512";
 289       # Log only a summary message on TLS handshake completion
 290       smtpd_tls_loglevel = "1";
 291       smtpd_tls_mandatory_ciphers = "high";
 292       smtpd_tls_mandatory_protocols = "TLSv1";
 293       # Only allow TLSv*
 294       smtpd_tls_protocols = [ "!SSLv2" "!SSLv3" ];
 295       #smtpd_tls_received_header = false;
 296       smtpd_tls_req_ccert = false;
 297       # Postfix 2.3 and later
 298       # encrypt
 299       #  Mandatory TLS encryption: announce STARTTLS support to SMTP clients, and require that clients use TLS
 300       #  encryption. According to [1720]RFC 2487 this MUST NOT be applied in case of a publicly-referenced
 301       #  SMTP server. Instead, this option should be used only on dedicated servers.
 302       smtpd_tls_security_level = "may";
 303       smtpd_tls_session_cache_database = "btree:$data_directory/smtpd_tls_session_cache";
 304       #smtpd_tls_session_cache_timeout = "3600s";
 305       # Stops mail from poorly written software
 306       strict_rfc821_envelopes = true;
 307       #sympa_destination_recipient_limit = "1";
 308       #sympabounce_destination_recipient_limit = "1";
 309       # postconf(5) discourages to change this
 310       #tls_high_cipherlist = "AES256-SHA";
 311       #tls_random_bytes = "32";
 312       # Must not be in a chroot
 313       #tls_random_exchange_name = "$data_directory/prng_exch";
 314       #tls_random_prng_update_period = "3600s";
 315       #tls_random_reseed_period = "3600s";
 316       # Use a non blocking source of randomness
 317       tls_random_source = "dev:/dev/urandom";
 318       transport_maps = [
 319         #"ldap:transport"
 320         #"hash:/etc/postfix/transport-dovecot"
 321         #"hash:/etc/postfix/$mydomain/transport"
 322         #"hash:/etc/dovecot/transport"
 323         #"regexp:/etc/sympa/transport"
 324       ];
 325       # Rejects immediately what $fallback_transport rejects
 326       unverified_recipient_reject_code = "550";
 327       # Do not specify virtual alias domain names in mydestination
 328       # or relay_domains configuration parameters
 329       #
 330       # With  a  virtual  alias  domain,  the  Postfix SMTP server
 331       # accepts  mail  for  known-user@virtual-alias.domain,   and
 332       # rejects   mail  for  unknown-user@virtual-alias.domain  as
 333       # undeliverable.
 334       virtual_alias_domains = [];
 335       virtual_alias_maps = [
 336         "hash:/etc/postfix/virtual_alias_maps"
 337         #TODO: "ldap:/etc/postfix/ldap-virtual_alias_maps.cf"
 338         #"hash:/etc/postfix/virtual_alias-dovecot"
 339         #"hash:/var/lib/postfix/conf/valias"
 340         #"regexp:/etc/sympa/virtual_alias"
 341       ];
 342       #virtual_uid_maps = "static:5000";
 343       #virtual_gid_maps = "static:5000";
 344       #virtual_mailbox_base = dovecot2.mailDir;
 345       virtual_mailbox_domains = toFile "virtual_mailbox_domains" (unlines (attrNames dovecot2.domains));
 346       #virtual_mailbox_maps = "hash:/etc/postfix/virtual_mailbox_maps";
 347       virtual_transport = "lmtp:unix:private/dovecot-lmtp";
 348     };
 349     #submissionOptions = {
 350     #  smtpd_tls_security_level     = "encrypt";
 351     #  smtpd_sasl_auth_enable       = "yes";
 352     #  smtpd_sasl_type              = "dovecot";
 353     #  smtpd_sasl_path              = "private/auth";
 354     #  smtpd_sasl_security_options  = "noanonymous";
 355     #  smtpd_sasl_local_domain      = "$myhostname";
 356     #  smtpd_client_restrictions    = "permit_sasl_authenticated,reject";
 357     #  smtpd_sender_login_maps      = "hash:/etc/postfix/vaccounts";
 358     #  smtpd_sender_restrictions    = "reject_sender_login_mismatch";
 359     #  smtpd_recipient_restrictions = "reject_non_fqdn_recipient,reject_unknown_recipient_domain,permit_sasl_authenticated,reject";
 360     #  cleanup_service_name         = "submission-header-cleanup";
 361     #};
 362     extraMasterConf = ''
 363       #spfcheck    unix  -        n       n       -        0        spawn
 364       #  user=policyd-spf argv=/usr/sbin/postfix-policyd-spf-perl
 365       465         inet  n        -       -       -        -        smtpd
 366         -o milter_macro_daemon_name=ORIGINATING
 367         -o smtpd_client_restrictions=permit_sasl_authenticated,reject
 368         -o smtpd_recipient_restrictions=reject_non_fqdn_recipient,reject_unknown_recipient_domain,permit_sasl_authenticated,reject
 369         -o smtpd_sasl_auth_enable=yes
 370         -o smtpd_sasl_local_domain=$myhostname
 371         -o smtpd_sasl_path=private/auth
 372         -o smtpd_sasl_security_options=noanonymous
 373         -o smtpd_sasl_type=dovecot
 374         -o smtpd_tls_ask_ccert=no
 375         -o smtpd_tls_auth_only=yes
 376         -o smtpd_tls_ccert_verifydepth=0
 377         -o smtpd_tls_loglevel=1
 378         -o smtpd_tls_req_ccert=no
 379         -o smtpd_tls_security_level=encrypt
 380         -o smtpd_tls_wrappermode=yes
 381       # -o smtpd_sender_restrictions=reject_sender_login_mismatch
 382       # -o smtpd_sender_login_maps=hash:/etc/postfix/vaccounts
 383       # -o cleanup_service_name=submission-header-cleanup
 384       submission-header-cleanup unix n - n    -       0       cleanup
 385         -o header_checks=pcre:${submissionHeaderCleanupRules}
 386       #spfcheck  unix  -       n       n       -       0       spawn
 387       #  user=policyd-spf argv=/usr/bin/postfix-policyd-spf-perl
 388       #uucp      unix  -       n       n       -       -       pipe
 389       #  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
 390       #smtp      inet  n       -       -       -       -       smtpd
 391       #  -o cleanup_service_name=pre-cleanup
 392       #  -o content_filter=amavis:[127.0.0.1]:10024
 393       #  -o smtpd_sender_restrictions=reject_unauth_pipelining,reject_non_fqdn_sender,permit
 394       #  -o receive_override_options=no_address_mappings
 395       #amavis    unix  -       -       n        -      2       lmtp
 396       #  -o lmtp_data_done_timeout=1200
 397       #  -o lmtp_send_xforward_command=yes
 398       #  -o lmtp_tls_note_starttls_offer=no
 399       #127.0.0.1:10025 inet n  -       n       -       -       smtpd
 400       #  -o content_filter=
 401       #  -o local_header_rewrite_clients=
 402       #  -o local_recipient_maps=
 403       #  -o mynetworks=127.0.0.0/8
 404       #  -o receive_override_options=no_header_body_checks,no_milters,no_unknown_recipient_checks
 405       #  -o relay_recipient_maps=
 406       #  -o smtpd_client_connection_count_limit=0
 407       #  -o smtpd_client_connection_rate_limit=0
 408       #  -o smtpd_client_restrictions=permit_mynetworks,reject
 409       #  -o smtpd_data_restrictions=reject_unauth_pipelining
 410       #  -o smtpd_delay_reject=no
 411       #  -o smtpd_end_of_data_restrictions=
 412       #  -o smtpd_error_sleep_time=0
 413       #  -o smtpd_hard_error_limit=1000
 414       #  -o smtpd_helo_restrictions=
 415       #  -o smtpd_milters=
 416       #  -o smtpd_recipient_restrictions=permit_mynetworks,reject
 417       #  -o smtpd_restriction_classes=
 418       #  -o smtpd_sender_restrictions=
 419       #  -o smtpd_soft_error_limit=1001
 420       #  -o strict_rfc821_envelopes=yes
 421       #submission inet n       -       -       -       -       smtpd
 422       #  -o cleanup_service_name=pre-cleanup
 423       #  -o content_filter=amavis:[127.0.0.1]:10024
 424       #  -o milter_macro_daemon_name=ORIGINATING
 425       #  -o receive_override_options=no_address_mappings
 426       #  -o smtpd_sender_restrictions=permit_tls_clientcerts,reject
 427       #  -o smtpd_tls_ask_ccert=yes
 428       #  -o smtpd_tls_auth_only=yes
 429       #  -o smtpd_tls_ccert_verifydepth=2
 430       #  -o smtpd_tls_loglevel=1
 431       #  -o smtpd_tls_req_ccert=yes
 432       #  -o smtpd_tls_security_level=encrypt
 433       #smtps     inet  n       -       -       -       -       smtpd
 434       #  -o milter_macro_daemon_name=ORIGINATING
 435       #  -o smtpd_client_restrictions=permit_sasl_authenticated,reject
 436       #  -o smtpd_sasl_auth_enable=yes
 437       #  -o smtpd_tls_ask_ccert=yes
 438       #  -o smtpd_tls_auth_only=yes
 439       #  -o smtpd_tls_ccert_verifydepth=0
 440       #  -o smtpd_tls_loglevel=1
 441       #  -o smtpd_tls_req_ccert=no
 442       #  -o smtpd_tls_security_level=encrypt
 443       #  -o smtpd_tls_wrappermode=yes
 444       #pickup    fifo  n       -       -       60      1       pickup
 445       #  -o cleanup_service_name=pre-cleanup
 446       #  -o content_filter=amavis:[127.0.0.1]:10024
 447       #pre-cleanup unix n      -       -       -       0       cleanup
 448       #  -o virtual_alias_maps=
 449       #cleanup   unix  n       -       -       -       0       cleanup
 450       #  -o mime_header_checks=
 451       #  -o nested_header_checks=
 452       #  -o body_checks=
 453       #  -o header_checks=
 454       #-- SYMPA begin
 455       #sympa unix - n n - - pipe
 456       #  flags=R user=sympa argv=/usr/lib/sympa/bin/queue ''${recipient}
 457       #sympabounce unix - n n - - pipe
 458       #  flags=R user=sympa argv=/usr/lib/sympa/bin/bouncequeue ''${recipient}
 459       #-- SYMPA end
 460     '';
 461      #noclue    unix  -       n       n       -       -       pipe
 462      #  flags=q user=noclue argv=/usr/local/bin/noclue-delivery ${recipient} ${sender}
 463   };
 464 };
 465 }