install/logical/friot/postfix.nix

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