hosts/mermet/postfix.nix

   1 { lib, config, ... }:
   2 let
   3   inherit (config) networking users;
   4   inherit (config.services) postfix;
   5 in
   6 {
   7   imports = [
   8     postfix/autogeree.net.nix
   9     postfix/sourcephile.fr.nix
  10   ];
  11   users.groups.acme.members = [ postfix.user ];
  12   networking.nftables.ruleset = ''
  13     table inet filter {
  14       chain input-net {
  15         tcp dport { smtp, submissions } counter accept comment "postfix: SMTP"
  16       }
  17       chain output-net {
  18         skuid ${postfix.user} tcp dport smtp counter accept comment "postfix: SMTP"
  19       }
  20     }
  21   '';
  22   services.postfix = {
  23     enable = true;
  24     networksStyle = "host";
  25     hostname = "${networking.hostName}.${networking.domain}";
  26     domain = networking.domain;
  27     origin = "$myhostname";
  28     destination = [
  29       "localhost"
  30       "localhost.localdomain"
  31       "$myhostname"
  32     ];
  33     postmasterAlias = "root";
  34     rootAlias = "root@${networking.domain}";
  35     sslKey = "/var/lib/acme/${networking.domain}/key.pem";
  36     sslCert = "/var/lib/acme/${networking.domain}/fullchain.pem";
  37     networks = [
  38       "127.0.0.0/8"
  39       "[::1]/128"
  40     ];
  41     setSendmail = true;
  42     # Parse the extension in email address, eg. contact+extension@
  43     recipientDelimiter = "+";
  44     #mapFiles.sender_access = postfix/sender_access.clear;
  45     #mapFiles.virtual_mailbox_maps = ;
  46     config = {
  47       debug_peer_level = "4";
  48       debug_peer_list = [
  49         #"chomsky.autogeree.net"
  50         #"localhost"
  51         #"mail.sourcephile.fr"
  52       ];
  53
  54       #
  55       # Sending to the world
  56       #
  57       # Appending .domain is the MUA's job
  58       append_dot_mydomain = false;
  59       smtp_body_checks = "";
  60       #smtp_cname_overrides_servername = false;
  61       smtp_connect_timeout = "60s";
  62       #smtp_header_checks = "regexp:/var/lib/postfix/smtp_header_checks";
  63       smtp_mime_header_checks = "";
  64       smtp_nested_header_checks = "";
  65       smtp_tls_exclude_ciphers = [ "ADH" "MD5" "CAMELLIA" "SEED" "3DES" "DES" "RC4" "eNULL" "aNULL" ];
  66       #smtp_tls_fingerprint_digest = "sha1";
  67       smtp_tls_loglevel = "1";
  68       #smtp_tls_note_starttls_offer = true;
  69       #smtp_tls_policy_maps = "hash:/var/lib/postfix/conf/tls_policy";
  70       # Only allow TLSv* protocols
  71       smtp_tls_protocols = [ "!SSLv2" "!SSLv3" ];
  72       #smtp_tls_scert_verifydepth = "5";
  73       #smtp_tls_secure_cert_match = [ "nexthop" "dot-nexthop" ];
  74       smtp_tls_security_level = "may";
  75       smtp_tls_session_cache_database = "btree:$data_directory/smtp_tls_session_cache";
  76       #smtp_tls_session_cache_timeout = "3600s";
  77       #smtp_tls_verify_cert_match = "hostname";
  78
  79       #
  80       # Receiving from the world
  81       #
  82       message_size_limit = "20480000";
  83       maximal_queue_lifetime = "5d";
  84       default_extra_recipient_limit = "5000";
  85       line_length_limit = "2048";
  86       duplicate_filter_limit = "5000";
  87       # Stops mail from poorly written software
  88       strict_rfc821_envelopes = true;
  89       mime_header_checks = [ ];
  90       milter_header_checks = [ ];
  91       nested_header_checks = [ ];
  92       body_checks = [ ];
  93       content_filter = "";
  94       permit_mx_backup_networks = [ ];
  95       propagate_unmatched_extensions = [ "canonical" "virtual" "alias" ];
  96       #masquerade_classes = [ "envelope_sender" "header_sender" "header_recipient" ];
  97       #masquerade_domains = "";
  98       #masquerade_exceptions = "root";
  99       queue_minfree = "0";
 100       # Stops some techniques used to harvest email addresses
 101       disable_vrfy_command = true;
 102       enable_long_queue_ids = false;
 103       # Useful to test restrictions
 104       smtpd_authorized_xclient_hosts = "127.0.0.1";
 105       smtpd_banner = "$myhostname ESMTP $mail_name (NixOS)";
 106       smtpd_client_connection_count_limit = "50";
 107       smtpd_client_connection_rate_limit = "0";
 108       smtpd_client_event_limit_exceptions = "$mynetworks";
 109       smtpd_client_message_rate_limit = "0";
 110       smtpd_client_new_tls_session_rate_limit = "0";
 111       smtpd_client_port_logging = false;
 112       smtpd_client_recipient_rate_limit = "0";
 113       # Ban 5 sec on error
 114       smtpd_error_sleep_time = "5";
 115       # Needed to enforce reject_unknown_helo_hostname
 116       smtpd_helo_required = true;
 117       smtpd_helo_restrictions = [
 118         "reject_invalid_helo_hostname"
 119         "reject_non_fqdn_helo_hostname"
 120         # Don't talk to mail systems that don't know their own hostname.
 121         "reject_unknown_helo_hostname"
 122         "permit"
 123       ];
 124       smtpd_client_restrictions = [
 125       ];
 126       # Set in postfix/*.nix and used in submissions/smptd
 127       # with reject_sender_login_mismatch
 128       smtpd_sender_login_maps = [ ];
 129       smtpd_sender_restrictions = [
 130         "reject_non_fqdn_sender"
 131         "check_sender_access hash:/etc/postfix/sender_access"
 132         "permit"
 133       ];
 134       smtpd_reject_unlisted_recipient = true;
 135       # Check the RCPT TO, before smtpd_recipient_restrictions
 136       # Restrictions based on what is allowed or not,
 137       # these are applied before smtpd_recipient_restrictions
 138       smtpd_relay_restrictions = [
 139         "permit_mynetworks"
 140         # Check the recipient's address in virtual_mailbox_domains and virtual_mailbox_maps
 141         "permit_auth_destination"
 142         # The world is only authorized to use our relay for the above destinations.
 143         "reject"
 144       ];
 145       # Restrictions based on what is working or not
 146       smtpd_recipient_restrictions = [
 147         # Reject if the domain is not fully qualified
 148         "reject_non_fqdn_recipient"
 149         # Reject if the domain is not working, even before bothering to check the address
 150         "reject_unknown_recipient_domain"
 151         # Reject if the address is not working
 152         # WARNING: this does not work if the recipient is greylisting.
 153         # WARNING: verify(8) has a cache, dumpable if verify(8) is stopped, with:
 154         # postmap -s btree:/var/lib/postfix/data/verify_cache
 155         #"reject_unverified_recipient"
 156         "permit"
 157       ];
 158       # Trust the verify database
 159       #unverified_recipient_reject_code = "550";
 160       smtpd_data_restrictions = [
 161         # Force the smtpd's client to wait OK before sending
 162         "reject_unauth_pipelining"
 163         "permit"
 164       ];
 165       smtpd_end_of_data_restrictions = [
 166         # Enforce mail volume quota via policy service callouts.
 167         #check_policy_service unix:private/policy
 168       ];
 169       #smtpd_milters = "";
 170       smtpd_peername_lookup = true;
 171       smtpd_recipient_limit = "5000";
 172       smtpd_recipient_overshoot_limit = "5000";
 173       #smtpd_restriction_classes = "";
 174       #smtpd_sasl_auth_enable = true;
 175       #smtpd_sasl_path = "private/auth";
 176       #smtpd_sasl_security_options = "noanonymous";
 177       #smtpd_sasl_type = "dovecot";
 178       smtpd_starttls_timeout = "300s";
 179       #smtpd_tls_always_issue_session_ids = true;
 180       #smtpd_tls_CApath = "/etc/postfix/x509/ca/";
 181       smtpd_tls_ask_ccert = false;
 182       #smtpd_tls_ccert_verifydepth = "5";
 183       smtpd_tls_ciphers = "high";
 184       smtpd_tls_eecdh_grade = "auto";
 185       # Disable weak ciphers as reported by https://ssl-tools.net
 186       # https://serverfault.com/questions/744168/how-to-disable-rc4-on-postfix
 187       smtpd_tls_exclude_ciphers = [ "ADH" "MD5" "CAMELLIA" "SEED" "3DES" "DES" "RC4" "eNULL" "aNULL" ];
 188       smtpd_tls_fingerprint_digest = "sha512";
 189       # Log only a summary message on TLS handshake completion
 190       smtpd_tls_loglevel = "1";
 191       smtpd_tls_mandatory_ciphers = "high";
 192       smtpd_tls_mandatory_protocols = [ "!SSLv2" "!SSLv3" ];
 193       # Only allow TLSv*
 194       smtpd_tls_protocols = [ "!SSLv2" "!SSLv3" ];
 195       #smtpd_tls_received_header = false;
 196       smtpd_tls_req_ccert = false;
 197       # Postfix 2.3 and later
 198       # encrypt
 199       #  Mandatory TLS encryption: announce STARTTLS support to SMTP clients, and require that clients use TLS
 200       #  encryption. According to [1720]RFC 2487 this MUST NOT be applied in case of a publicly-referenced
 201       #  SMTP server. Instead, this option should be used only on dedicated servers.
 202       smtpd_tls_security_level = "may";
 203       smtpd_tls_session_cache_database = "btree:$data_directory/smtpd_tls_session_cache";
 204       #smtpd_tls_session_cache_timeout = "3600s";
 205       #smtpd_tls_chain_files =
 206
 207       relayhost = [ ];
 208       #relay_clientcerts = hash:/var/lib/postfix/conf/relay_clientcerts
 209       # This is where to put backup MX domains
 210       relay_domains = [ ];
 211       relay_recipient_maps = [ ];
 212
 213       # Use a non blocking source of randomness
 214       tls_random_source = "dev:/dev/urandom";
 215       # Map each domain to a specific X.509 certificate
 216       tls_server_sni_maps = "hash:/run/keys/postfix-sni";
 217
 218       # Only explicitely aliased accounts have a mail, not all the passwd
 219       #local_recipient_maps = "$alias_maps";
 220       # Note that the local transport rewrites the envelope recipient
 221       # according to the alias_maps, and thus the aliasing is transparent
 222       # to the nexthop (eg. dovecot)
 223       #local_transport = local:$myhostname
 224       # No console bell on new mail
 225       biff = false;
 226       forward_path = [
 227         /*
 228       "$home/.forward''${recipient_delimiter}''${extension}"
 229         */
 230         "$home/.forward"
 231       ];
 232
 233       # Filled by the postfix/*.nix
 234       virtual_mailbox_domains = [ ];
 235       # Completed by the postfix/*.nix
 236       virtual_mailbox_maps = [
 237         # Is it necessary because it's already in virtual_alias_maps
 238         "hash:/etc/postfix/virtual"
 239       ];
 240       virtual_transport = "lmtp:unix:private/dovecot-lmtp";
 241       /*
 242         dovecot_destination_recipient_limit = "1";
 243         virtual_transport = "dovecot";
 244       */
 245
 246       # There is no fallback
 247       fallback_transport = "";
 248     };
 249     virtualMapType = "hash";
 250     masterConfig =
 251       let
 252         mkVal = value:
 253           if lib.isList value
 254           then lib.concatStringsSep "," value
 255           else
 256             if value == true then "yes"
 257             else if value == false then "no"
 258             else toString value;
 259         mkKeyVal = opt: val: [ "-o" (opt + "=" + mkVal val) ];
 260         mkArgs = args: lib.concatLists (lib.mapAttrsToList mkKeyVal args);
 261       in
 262       {
 263         pickup = {
 264           args = mkArgs {
 265             cleanup_service_name = "submissions-header-cleanup";
 266           };
 267         };
 268         # Implicit TLS on port 465
 269         # https://tools.ietf.org/html/rfc8314#section-3.3
 270         submissions = {
 271           type = "inet";
 272           private = false;
 273           command = "smtpd";
 274           args = mkArgs {
 275             syslog_name = "postfix/submissions";
 276             # Implicit TLS, not STARTTLS
 277             smtpd_tls_wrappermode = true;
 278             smtpd_tls_mandatory_protocols = [
 279               "TLSv1.3"
 280               # FIXME: to be removed when K-9 Mail will support TLSv1.3,
 281               # K-9 Mail 5.600 does not.
 282               "TLSv1.2"
 283             ];
 284             milter_macro_daemon_name = "ORIGINATING";
 285             smtpd_helo_restrictions = [
 286               "permit_sasl_authenticated"
 287             ] ++ postfix.config.smtpd_helo_restrictions;
 288             smtpd_relay_restrictions = [
 289               # SASL authorizes to send to the world
 290               "permit_sasl_authenticated"
 291               "reject"
 292             ];
 293             smtpd_sasl_auth_enable = true;
 294             smtpd_sasl_type = "dovecot";
 295             smtpd_sasl_path = "private/auth";
 296             smtpd_sasl_local_domain = "";
 297             # Offer SASL authentication only after a TLS-encrypted session has been established
 298             smtpd_tls_auth_only = true;
 299             smtpd_sasl_tls_security_options = [ "noanonymous" ];
 300             # Do not put SASL logins in mail headers
 301             smtpd_sasl_authenticated_header = false;
 302             # Who cares about (old) Outlook
 303             broken_sasl_auth_clients = false;
 304             smtpd_sender_restrictions = [
 305               "reject_non_fqdn_sender"
 306               # Check that the SASL user is using only its own
 307               # mail addresses on the envelope, as indicated in smtpd_sender_login_maps
 308               "reject_sender_login_mismatch"
 309               "permit"
 310             ];
 311             # No X.509 certificates for users, for now
 312             smtpd_tls_ask_ccert = false;
 313             smtpd_tls_ccert_verifydepth = 0;
 314             smtpd_tls_loglevel = 1;
 315             smtpd_tls_req_ccert = false;
 316             cleanup_service_name = "submissions-header-cleanup";
 317           };
 318         };
 319       };
 320     extraMasterConf = ''
 321       #spfcheck    unix  -        n       n       -        0        spawn
 322       #  user=policyd-spf argv=/usr/sbin/postfix-policyd-spf-perl
 323       # -o smtpd_sender_restrictions=reject_sender_login_mismatch
 324       # -o smtpd_sender_login_maps=hash:/etc/postfix/vaccounts
 325       # -o cleanup_service_name=submissions-header-cleanup
 326       #spfcheck  unix  -       n       n       -       0       spawn
 327       #  user=policyd-spf argv=/usr/bin/postfix-policyd-spf-perl
 328       #uucp      unix  -       n       n       -       -       pipe
 329       #  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
 330       #smtp      inet  n       -       -       -       -       smtpd
 331       #  -o cleanup_service_name=pre-cleanup
 332       #  -o content_filter=amavis:[127.0.0.1]:10024
 333       #  -o smtpd_sender_restrictions=reject_unauth_pipelining,reject_non_fqdn_sender,permit
 334       #  -o receive_override_options=no_address_mappings
 335       #amavis    unix  -       -       n        -      2       lmtp
 336       #  -o lmtp_data_done_timeout=1200
 337       #  -o lmtp_send_xforward_command=yes
 338       #  -o lmtp_tls_note_starttls_offer=no
 339       #127.0.0.1:10025 inet n  -       n       -       -       smtpd
 340       #  -o content_filter=
 341       #  -o local_header_rewrite_clients=
 342       #  -o local_recipient_maps=
 343       #  -o mynetworks=127.0.0.0/8
 344       #  -o receive_override_options=no_header_body_checks,no_milters,no_unknown_recipient_checks
 345       #  -o relay_recipient_maps=
 346       #  -o smtpd_client_connection_count_limit=0
 347       #  -o smtpd_client_connection_rate_limit=0
 348       #  -o smtpd_client_restrictions=permit_mynetworks,reject
 349       #  -o smtpd_data_restrictions=reject_unauth_pipelining
 350       #  -o smtpd_delay_reject=no
 351       #  -o smtpd_end_of_data_restrictions=
 352       #  -o smtpd_error_sleep_time=0
 353       #  -o smtpd_hard_error_limit=1000
 354       #  -o smtpd_helo_restrictions=
 355       #  -o smtpd_milters=
 356       #  -o smtpd_recipient_restrictions=permit_mynetworks,reject
 357       #  -o smtpd_restriction_classes=
 358       #  -o smtpd_sender_restrictions=
 359       #  -o smtpd_soft_error_limit=1001
 360       #  -o strict_rfc821_envelopes=yes
 361       #submission inet n       -       -       -       -       smtpd
 362       #  -o cleanup_service_name=pre-cleanup
 363       #  -o content_filter=amavis:[127.0.0.1]:10024
 364       #  -o milter_macro_daemon_name=ORIGINATING
 365       #  -o receive_override_options=no_address_mappings
 366       #  -o smtpd_sender_restrictions=permit_tls_clientcerts,reject
 367       #  -o smtpd_tls_ask_ccert=yes
 368       #  -o smtpd_tls_auth_only=yes
 369       #  -o smtpd_tls_ccert_verifydepth=2
 370       #  -o smtpd_tls_loglevel=1
 371       #  -o smtpd_tls_req_ccert=yes
 372       #  -o smtpd_tls_security_level=encrypt
 373       #smtps     inet  n       -       -       -       -       smtpd
 374       #  -o milter_macro_daemon_name=ORIGINATING
 375       #  -o smtpd_client_restrictions=permit_sasl_authenticated,reject
 376       #  -o smtpd_sasl_auth_enable=yes
 377       #  -o smtpd_tls_ask_ccert=yes
 378       #  -o smtpd_tls_auth_only=yes
 379       #  -o smtpd_tls_ccert_verifydepth=0
 380       #  -o smtpd_tls_loglevel=1
 381       #  -o smtpd_tls_req_ccert=no
 382       #  -o smtpd_tls_security_level=encrypt
 383       #  -o smtpd_tls_wrappermode=yes
 384       #pickup    fifo  n       -       -       60      1       pickup
 385       #  -o cleanup_service_name=pre-cleanup
 386       #  -o content_filter=amavis:[127.0.0.1]:10024
 387       #pre-cleanup unix n      -       -       -       0       cleanup
 388       #  -o virtual_alias_maps=
 389       #cleanup   unix  n       -       -       -       0       cleanup
 390       #  -o mime_header_checks=
 391       #  -o nested_header_checks=
 392       #  -o body_checks=
 393       #  -o header_checks=
 394       #-- SYMPA begin
 395       #sympa unix - n n - - pipe
 396       #  flags=R user=sympa argv=/usr/lib/sympa/bin/queue ''${recipient}
 397       #sympabounce unix - n n - - pipe
 398       #  flags=R user=sympa argv=/usr/lib/sympa/bin/bouncequeue ''${recipient}
 399       #-- SYMPA end
 400     '';
 401     #noclue    unix  -       n       n       -       -       pipe
 402     #  flags=q user=noclue argv=/usr/local/bin/noclue-delivery ${recipient} ${sender}
 403   };
 404 }