Postfix manual - cleanup(8)

    CLEANUP(8)                                                          CLEANUP(8)

    NAME
           cleanup - canonicalize and enqueue Postfix message

    SYNOPSIS
           cleanup [generic Postfix daemon options]

    DESCRIPTION
           The  cleanup(8)  daemon  processes  inbound  mail,  inserts it into the
           incoming mail queue, and informs the queue manager of its arrival.

           The cleanup(8) daemon always performs the following transformations:

           o      Insert missing  message  headers:  (Resent-)  From:,  To:,  Mes-
                  sage-Id:, and Date:.

           o      Transform   envelope   and  header  addresses  to  the  standard
                  user@fully-qualified-domain form that is expected by other Post-
                  fix  programs.  This task is delegated to the trivial-rewrite(8)
                  daemon.

           o      Eliminate duplicate envelope recipient addresses.

           o      Remove  message  headers:   Bcc,   Content-Length,   Resent-Bcc,
                  Return-Path.

           The following address transformations are optional:

           o      Optionally,  rewrite all envelope and header addresses according
                  to the mappings specified in the canonical(5) lookup tables.

           o      Optionally, masquerade envelope  sender  addresses  and  message
                  header  addresses  (i.e.  strip host or domain information below
                  all domains listed in the masquerade_domains  parameter,  except
                  for  user  names  listed in masquerade_exceptions).  By default,
                  address masquerading does not affect envelope recipients.

           o      Optionally, expand envelope recipients according to  information
                  found in the virtual(5) lookup tables.

           The  cleanup(8)  daemon  performs  sanity checks on the content of each
           message. When it finds a problem, by default it  returns  a  diagnostic
           status  to  the client, and leaves it up to the client to deal with the
           problem. Alternatively, the client can request the cleanup(8) daemon to
           bounce the message back to the sender in case of trouble.

    STANDARDS
           RFC 822 (ARPA Internet Text Messages)
           RFC 2045 (MIME: Format of Internet Message Bodies)
           RFC 2046 (MIME: Media Types)
           RFC 2822 (Internet Message Format)
           RFC 3463 (Enhanced Status Codes)
           RFC 3464 (Delivery status notifications)
           RFC 5322 (Internet Message Format)

    DIAGNOSTICS
           Problems and transactions are logged to syslogd(8).

    BUGS
           Table-driven  rewriting  rules make it hard to express if then else and
           other logical relationships.

    CONFIGURATION PARAMETERS
           Changes to main.cf are picked up automatically, as cleanup(8) processes
           run for only a limited amount of time. Use the command "postfix reload"
           to speed up a change.

           The text below provides only a parameter summary. See  postconf(5)  for
           more details including examples.

    COMPATIBILITY CONTROLS
           undisclosed_recipients_header (see 'postconf -d' output)
                  Message header that the Postfix cleanup(8) server inserts when a
                  message contains no To: or Cc: message header.

           Available in Postfix version 2.1 only:

           enable_errors_to (no)
                  Report mail delivery errors to the address  specified  with  the
                  non-standard  Errors-To: message header, instead of the envelope
                  sender address (this feature is  removed  with  Postfix  version
                  2.2,  is  turned off by default with Postfix version 2.1, and is
                  always turned on with older Postfix versions).

           Available in Postfix version 2.6 and later:

           always_add_missing_headers (no)
                  Always add (Resent-) From:, To:, Date:  or  Message-ID:  headers
                  when not present.

           Available in Postfix version 2.9 and later:

           enable_long_queue_ids (no)
                  Enable long, non-repeating, queue IDs (queue file names).

           Available in Postfix version 3.0 and later:

           message_drop_headers (bcc, content-length, resent-bcc, return-path)
                  Names  of message headers that the cleanup(8) daemon will remove
                  after  applying  header_checks(5)  and  before  invoking  Milter
                  applications.

    BUILT-IN CONTENT FILTERING CONTROLS
           Postfix built-in content filtering is meant to stop a flood of worms or
           viruses. It is not a general content filter.

           body_checks (empty)
                  Optional lookup tables for content inspection  as  specified  in
                  the body_checks(5) manual page.

           header_checks (empty)
                  Optional   lookup  tables  for  content  inspection  of  primary
                  non-MIME message headers, as specified in  the  header_checks(5)
                  manual page.

           Available in Postfix version 2.0 and later:

           body_checks_size_limit (51200)
                  How  much  text in a message body segment (or attachment, if you
                  prefer to use that term) is subjected to body_checks inspection.

           mime_header_checks ($header_checks)
                  Optional  lookup  tables  for content inspection of MIME related
                  message headers, as described  in  the  header_checks(5)  manual
                  page.

           nested_header_checks ($header_checks)
                  Optional  lookup  tables for content inspection of non-MIME mes-
                  sage  headers  in  attached  messages,  as  described   in   the
                  header_checks(5) manual page.

           Available in Postfix version 2.3 and later:

           message_reject_characters (empty)
                  The  set  of characters that Postfix will reject in message con-
                  tent.

           message_strip_characters (empty)
                  The set of characters that Postfix will remove from message con-
                  tent.

    BEFORE QUEUE MILTER CONTROLS
           As of version 2.3, Postfix supports the Sendmail version 8 Milter (mail
           filter) protocol. When mail is not received via  the  smtpd(8)  server,
           the cleanup(8) server will simulate SMTP events to the extent that this
           is possible. For details see the MILTER_README document.

           non_smtpd_milters (empty)
                  A list of Milter (mail filter) applications for  new  mail  that
                  does not arrive via the Postfix smtpd(8) server.

           milter_protocol (6)
                  The  mail  filter  protocol version and optional protocol exten-
                  sions for communication with  a  Milter  application;  prior  to
                  Postfix 2.6 the default protocol is 2.

           milter_default_action (tempfail)
                  The  default  action  when a Milter (mail filter) application is
                  unavailable or mis-configured.

           milter_macro_daemon_name ($myhostname)
                  The {daemon_name} macro value for Milter (mail filter)  applica-
                  tions.

           milter_macro_v ($mail_name $mail_version)
                  The {v} macro value for Milter (mail filter) applications.

           milter_connect_timeout (30s)
                  The time limit for connecting to a Milter (mail filter) applica-
                  tion, and for negotiating protocol options.

           milter_command_timeout (30s)
                  The time limit for sending an SMTP command  to  a  Milter  (mail
                  filter) application, and for receiving the response.

           milter_content_timeout (300s)
                  The  time  limit  for  sending message content to a Milter (mail
                  filter) application, and for receiving the response.

           milter_connect_macros (see 'postconf -d' output)
                  The macros that are sent to Milter  (mail  filter)  applications
                  after completion of an SMTP connection.

           milter_helo_macros (see 'postconf -d' output)
                  The  macros  that  are sent to Milter (mail filter) applications
                  after the SMTP HELO or EHLO command.

           milter_mail_macros (see 'postconf -d' output)
                  The macros that are sent to Milter  (mail  filter)  applications
                  after the SMTP MAIL FROM command.

           milter_rcpt_macros (see 'postconf -d' output)
                  The  macros  that  are sent to Milter (mail filter) applications
                  after the SMTP RCPT TO command.

           milter_data_macros (see 'postconf -d' output)
                  The macros that are sent to version 4  or  higher  Milter  (mail
                  filter) applications after the SMTP DATA command.

           milter_unknown_command_macros (see 'postconf -d' output)
                  The  macros  that  are  sent to version 3 or higher Milter (mail
                  filter) applications after an unknown SMTP command.

           milter_end_of_data_macros (see 'postconf -d' output)
                  The macros that are sent to Milter  (mail  filter)  applications
                  after the message end-of-data.

           Available in Postfix version 2.5 and later:

           milter_end_of_header_macros (see 'postconf -d' output)
                  The  macros  that  are sent to Milter (mail filter) applications
                  after the end of the message header.

           Available in Postfix version 2.7 and later:

           milter_header_checks (empty)
                  Optional lookup tables for content inspection of message headers
                  that are produced by Milter applications.

           Available in Postfix version 3.1 and later:

           milter_macro_defaults (empty)
                  Optional  list  of  name=value pairs that specify default values
                  for arbitrary macros that Postfix may send  to  Milter  applica-
                  tions.

    MIME PROCESSING CONTROLS
           Available in Postfix version 2.0 and later:

           disable_mime_input_processing (no)
                  Turn off MIME processing while receiving mail.

           mime_boundary_length_limit (2048)
                  The maximal length of MIME multipart boundary strings.

           mime_nesting_limit (100)
                  The maximal recursion level that the MIME processor will handle.

           strict_8bitmime (no)
                  Enable both strict_7bit_headers and strict_8bitmime_body.

           strict_7bit_headers (no)
                  Reject mail with 8-bit text in message headers.

           strict_8bitmime_body (no)
                  Reject 8-bit message body text without 8-bit MIME content encod-
                  ing information.

           strict_mime_encoding_domain (no)
                  Reject  mail with invalid Content-Transfer-Encoding: information
                  for the message/* or multipart/* MIME content types.

           Available in Postfix version 2.5 and later:

           detect_8bit_encoding_header (yes)
                  Automatically detect 8BITMIME body content by  looking  at  Con-
                  tent-Transfer-Encoding:   message  headers;  historically,  this
                  behavior was hard-coded to be "always on".

    AUTOMATIC BCC RECIPIENT CONTROLS
           Postfix can automatically add BCC (blind carbon copy) when mail  enters
           the mail system:

           always_bcc (empty)
                  Optional  address  that  receives  a "blind carbon copy" of each
                  message that is received by the Postfix mail system.

           Available in Postfix version 2.1 and later:

           sender_bcc_maps (empty)
                  Optional BCC (blind carbon-copy) address lookup tables,  indexed
                  by sender address.

           recipient_bcc_maps (empty)
                  Optional  BCC (blind carbon-copy) address lookup tables, indexed
                  by recipient address.

    ADDRESS TRANSFORMATION CONTROLS
           Address rewriting is delegated to the trivial-rewrite(8)  daemon.   The
           cleanup(8) server implements table driven address mapping.

           empty_address_recipient (MAILER-DAEMON)
                  The recipient of mail addressed to the null address.

           canonical_maps (empty)
                  Optional  address  mapping lookup tables for message headers and
                  envelopes.

           recipient_canonical_maps (empty)
                  Optional address mapping lookup tables for envelope  and  header
                  recipient addresses.

           sender_canonical_maps (empty)
                  Optional  address  mapping lookup tables for envelope and header
                  sender addresses.

           masquerade_classes (envelope_sender, header_sender, header_recipient)
                  What addresses are subject to address masquerading.

           masquerade_domains (empty)
                  Optional list of  domains  whose  subdomain  structure  will  be
                  stripped off in email addresses.

           masquerade_exceptions (empty)
                  Optional  list  of  user names that are not subjected to address
                  masquerading,  even  when  their   address   matches   $masquer-
                  ade_domains.

           propagate_unmatched_extensions (canonical, virtual)
                  What  address  lookup  tables copy an address extension from the
                  lookup key to the lookup result.

           Available before Postfix version 2.0:

           virtual_maps (empty)
                  Optional lookup tables with a) names of domains  for  which  all
                  addresses  are  aliased  to  addresses  in other local or remote
                  domains, and b) addresses that are aliased to addresses in other
                  local or remote domains.

           Available in Postfix version 2.0 and later:

           virtual_alias_maps ($virtual_maps)
                  Optional  lookup  tables  that  alias specific mail addresses or
                  domains to other local or remote address.

           Available in Postfix version 2.2 and later:

           canonical_classes (envelope_sender, envelope_recipient,  header_sender,
           header_recipient)
                  What addresses are subject to canonical_maps address mapping.

           recipient_canonical_classes (envelope_recipient, header_recipient)
                  What addresses are subject to  recipient_canonical_maps  address
                  mapping.

           sender_canonical_classes (envelope_sender, header_sender)
                  What addresses are subject to sender_canonical_maps address map-
                  ping.

           remote_header_rewrite_domain (empty)
                  Don't rewrite message headers from remote clients  at  all  when
                  this  parameter is empty; otherwise, rewrite message headers and
                  append the specified domain name to incomplete addresses.

    RESOURCE AND RATE CONTROLS
           duplicate_filter_limit (1000)
                  The maximal number of addresses remembered by the address dupli-
                  cate filter for aliases(5) or virtual(5) alias expansion, or for
                  showq(8) queue displays.

           header_size_limit (102400)
                  The maximal amount of memory in  bytes  for  storing  a  message
                  header.

           hopcount_limit (50)
                  The maximal number of Received:  message headers that is allowed
                  in the primary message headers.

           in_flow_delay (1s)
                  Time to pause before accepting a new message, when  the  message
                  arrival rate exceeds the message delivery rate.

           message_size_limit (10240000)
                  The  maximal  size  in  bytes  of  a message, including envelope
                  information.

           Available in Postfix version 2.0 and later:

           header_address_token_limit (10240)
                  The maximal number of address tokens are allowed in  an  address
                  message header.

           mime_boundary_length_limit (2048)
                  The maximal length of MIME multipart boundary strings.

           mime_nesting_limit (100)
                  The maximal recursion level that the MIME processor will handle.

           queue_file_attribute_count_limit (100)
                  The maximal number of (name=value) attributes that may be stored
                  in a Postfix queue file.

           Available in Postfix version 2.1 and later:

           virtual_alias_expansion_limit (1000)
                  The  maximal  number  of  addresses that virtual alias expansion
                  produces from each original recipient.

           virtual_alias_recursion_limit (1000)
                  The maximal nesting depth of virtual alias expansion.

           Available in Postfix version 3.0 and later:

           virtual_alias_address_length_limit (1000)
                  The maximal length of  an  email  address  after  virtual  alias
                  expansion.

    SMTPUTF8 CONTROLS
           Preliminary SMTPUTF8 support is introduced with Postfix 3.0.

           smtputf8_enable (yes)
                  Enable  preliminary SMTPUTF8 support for the protocols described
                  in RFC 6531..6533.

           smtputf8_autodetect_classes (sendmail, verify)
                  Detect that a message requires SMTPUTF8 support for  the  speci-
                  fied mail origin classes.

    MISCELLANEOUS CONTROLS
           config_directory (see 'postconf -d' output)
                  The  default  location of the Postfix main.cf and master.cf con-
                  figuration files.

           daemon_timeout (18000s)
                  How much time a Postfix daemon process  may  take  to  handle  a
                  request before it is terminated by a built-in watchdog timer.

           delay_logging_resolution_limit (2)
                  The  maximal  number of digits after the decimal point when log-
                  ging sub-second delay values.

           delay_warning_time (0h)
                  The time after which the sender receives a copy of  the  message
                  headers of mail that is still queued.

           ipc_timeout (3600s)
                  The  time  limit  for  sending  or receiving information over an
                  internal communication channel.

           max_idle (100s)
                  The maximum amount of time that an idle Postfix  daemon  process
                  waits for an incoming connection before terminating voluntarily.

           max_use (100)
                  The maximal number of incoming connections that a Postfix daemon
                  process will service before terminating voluntarily.

           myhostname (see 'postconf -d' output)
                  The internet hostname of this mail system.

           myorigin ($myhostname)
                  The  domain  name that locally-posted mail appears to come from,
                  and that locally posted mail is delivered to.

           process_id (read-only)
                  The process ID of a Postfix command or daemon process.

           process_name (read-only)
                  The process name of a Postfix command or daemon process.

           queue_directory (see 'postconf -d' output)
                  The location of the Postfix top-level queue directory.

           soft_bounce (no)
                  Safety net to keep mail queued that would otherwise be  returned
                  to the sender.

           syslog_facility (mail)
                  The syslog facility of Postfix logging.

           syslog_name (see 'postconf -d' output)
                  The  mail  system  name that is prepended to the process name in
                  syslog records, so that "smtpd"  becomes,  for  example,  "post-
                  fix/smtpd".

           Available in Postfix version 2.1 and later:

           enable_original_recipient (yes)
                  Enable support for the X-Original-To message header.

    FILES
           /etc/postfix/canonical*, canonical mapping table
           /etc/postfix/virtual*, virtual mapping table

    SEE ALSO
           trivial-rewrite(8), address rewriting
           qmgr(8), queue manager
           header_checks(5), message header content inspection
           body_checks(5), body parts content inspection
           canonical(5), canonical address lookup table format
           virtual(5), virtual alias lookup table format
           postconf(5), configuration parameters
           master(5), generic daemon options
           master(8), process manager
           syslogd(8), system logging

    README FILES
           ADDRESS_REWRITING_README Postfix address manipulation
           CONTENT_INSPECTION_README content inspection

    LICENSE
           The Secure Mailer license must be distributed with this software.

    AUTHOR(S)
           Wietse Venema
           IBM T.J. Watson Research
           P.O. Box 704
           Yorktown Heights, NY 10598, USA

                                                                        CLEANUP(8)