chiark - git - mdw - exim-config/blob - exchange.m4

   1 ### -*-m4-*-
   2 ###
   3 ### Transmission to remote hosts for distorted.org.uk Exim configuration.
   4 ###
   5 ### (c) 2012 Mark Wooding
   6 ###
   7
   8 ###----- Licensing notice ---------------------------------------------------
   9 ###
  10 ### This program is free software; you can redistribute it and/or modify
  11 ### it under the terms of the GNU General Public License as published by
  12 ### the Free Software Foundation; either version 2 of the License, or
  13 ### (at your option) any later version.
  14 ###
  15 ### This program is distributed in the hope that it will be useful,
  16 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ### GNU General Public License for more details.
  19 ###
  20 ### You should have received a copy of the GNU General Public License
  21 ### along with this program; if not, write to the Free Software Foundation,
  22 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23
  24 ###--------------------------------------------------------------------------
  25 ### Listen for incoming connections.
  26
  27 SECTION(global, daemon)m4_dnl
  28 daemon_smtp_ports = CONF_smtp_port : CONF_submission_port
  29
  30 DIVERT(null)
  31 ###--------------------------------------------------------------------------
  32 ### Check source addresses for apparently local senders.
  33
  34 SECTION(acl, mail-hooks)m4_dnl
  35         ## Check that a submitted message's sender address is allowable.
  36         require  acl = mail_client_addr
  37
  38 SECTION(acl, misc)m4_dnl
  39 mail_client_addr:
  40
  41         ## If this is a message submission then that's handled elsewhere.
  42         accept   condition = ${if eq{$acl_c_mode}{submission}}
  43
  44         ## Make sure that the sender matches the client address.  I feel like
  45         ## I want to reject these, but that will break stuff.  For example,
  46         ## if I send mail to an externally hosted address which is really a
  47         ## distribution list containing some local address, then we'll
  48         ## (approximately legitimately) receive mail with an apparently-local
  49         ## sender from a remote host.
  50         warn    !hosts = ${LOOKUP_DOMAIN($sender_address_domain,
  51                            {KV(hosts, {$value}{+allnets})},
  52                            {${if match_domain {$sender_address_domain} \
  53                                               {+public} \
  54                                  {+allnets}{! +allnets}}})}
  55                  add_header = :after_received:X-Distorted-Warning: \
  56                         RCLNTLSNDR \
  57                         Apparently local sender, but received from remote \
  58                         server.\n\t\
  59                         sender=$sender_address \
  60                         host=$sender_host_address
  61
  62         ## OK.
  63         accept
  64
  65 DIVERT(null)
  66 ###--------------------------------------------------------------------------
  67 ### The obvious trivial router.
  68
  69 SECTION(routers, remote)m4_dnl
  70 ## Send mail on to a host in our own network.  We must apply extra security.
  71 local:
  72         driver = dnslookup
  73         domains = ${if bool {${LOOKUP_DOMAIN($domain,
  74                                {KV(service, {$value}{true})},
  75                                {false})}} \
  76                        {}{ ! +public : \
  77                            CONF_master_domain : \
  78                            *.CONF_master_domain }}
  79         self = fail
  80         transport = smtp_local
  81         no_more
  82
  83 ## Send mail on to unknown hosts.
  84 remote:
  85         driver = dnslookup
  86         domains = ${if bool {${LOOKUP_DOMAIN($domain,
  87                                {KV(service, {$value}{true})},
  88                                {false})}} \
  89                        {}{ ! +public }}
  90         self = fail
  91         transport = smtp
  92         no_more
  93
  94 DIVERT(null)
  95 ###----- That's all, folks --------------------------------------------------