Argthtjtr

I'm having a hard time coming up with a router or filter to basically send ALL incoming emails to a domain name to a Ruby script, for an Exim setup on a CentOS7 board.

The resolution from https://stackoverflow.com/a/32178818/10690518 no longer seems to be valid, the /etc/aliases method doesn't seem to work and the Exim manual, whilst fairly thorough, does not get me to the point where I can create the correct route.

This is my fairly standard Exim config:

# cat /etc/exim/exim.conf |egrep -v '^#|^$|  #'

primary_hostname = MYDOMAIN

domainlist local_domains = @ : localhost : localhost.localdomain : MYDOMAIN

domainlist relay_to_domains = MYDOMAIN

hostlist   relay_from_hosts = localhost

acl_smtp_mail = acl_check_mail

acl_smtp_rcpt = acl_check_rcpt

acl_smtp_data = acl_check_data

acl_smtp_mime = acl_check_mime

av_scanner = clamd:/var/run/clamd.exim/clamd.sock

tls_advertise_hosts = *

tls_certificate = /etc/ssl/certs/MYDOMAIN.pem

daemon_smtp_ports = 25 : 465 : 587

tls_on_connect_ports = 465

never_users = root

host_lookup = *

auth_advertise_hosts =

prdr_enable = true

log_selector = +smtp_protocol_error +smtp_syntax_error 

    +tls_certificate_verified

ignore_bounce_errors_after = 2d

timeout_frozen_after = 7d

keep_environment = ^LDAP

add_environment = PATH=/usr/bin::/bin

begin acl

acl_check_mail:

  deny condition = ${if eq{$sender_helo_name}{} {1}}

       message = Nice boys say HELO first

  warn condition = ${if eq{$sender_host_name}{} {1}}

       set acl_m_greylistreasons = Host $sender_host_address lacks reverse DNSn$acl_m_greylistreasons

  accept

acl_check_rcpt:

  accept  hosts = :

          control = dkim_disable_verify

  deny    message       = Restricted characters in address

          domains       = +local_domains

          local_parts   = ^[.] : ^.*[@%!/|]

  deny    message       = Restricted characters in address

          domains       = !+local_domains

          local_parts   = ^[./|] : ^.*[@%!] : ^.*/\.\./

  accept  local_parts   = postmaster

          domains       = +local_domains

  require verify        = sender

  accept  hosts         = +relay_from_hosts

          control       = submission

          control       = dkim_disable_verify

  accept  authenticated = *

          control       = submission

          control       = dkim_disable_verify

  require message   = nice hosts say HELO first

          condition = ${if def:sender_helo_name}

  require message = relay not permitted

          domains = +local_domains : +relay_to_domains

  require verify = recipient

  accept

acl_check_data:

  deny    message    = maximum allowed line length is 998 octets, 

                       got $max_received_linelength

          condition  = ${if > {$max_received_linelength}{998}}

  deny    !verify = header_syntax

      message = header syntax

      log_message = header syntax ($acl_verify_message)

  warn    condition  = ${if !def:h_Message-ID: {1}}

          set acl_m_greylistreasons = Message lacks Message-Id: header. Consult RFC2822.n$acl_m_greylistreasons

  accept

acl_check_mime:

  deny message = Blacklisted file extension detected

       condition = ${if match 

                        {${lc:$mime_filename}} 

                        {N(.exe|.pif|.bat|.scr|.lnk|.com)$N} 

                     {1}{0}}

  accept

begin routers

dnslookup:

  driver = dnslookup

  domains = ! +local_domains

  transport = remote_smtp

  ignore_target_hosts = 0.0.0.0 : 127.0.0.0/8

  no_more

system_aliases:

  driver = redirect

  allow_fail

  allow_defer

  data = ${lookup{$local_part}lsearch{/etc/aliases}}

  file_transport = address_file

  pipe_transport = address_pipe

userforward:

  driver = redirect

  check_local_user

  file = $home/.forward

  allow_filter

  no_verify

  no_expn

  check_ancestor

  file_transport = address_file

  pipe_transport = address_pipe

  reply_transport = address_reply

procmail:

  driver = accept

  check_local_user

  require_files = ${local_part}:+${home}/.procmailrc:/usr/bin/procmail

  transport = procmail

  no_verify

localuser:

  driver = accept

  check_local_user

  transport = local_delivery

  cannot_route_message = Unknown user

begin transports

remote_smtp:

  driver = smtp

  message_size_limit = ${if > {$max_received_linelength}{998} {1}{0}}

remote_msa:

  driver = smtp

  port = 587

  hosts_require_auth = *

procmail:

  driver = pipe

  command = "/usr/bin/procmail -d $local_part"

  return_path_add

  delivery_date_add

  envelope_to_add

  user = $local_part

  initgroups

  return_output

local_delivery:

  driver = appendfile

  file = /var/mail/$local_part

  delivery_date_add

  envelope_to_add

  return_path_add

  group = mail

  mode = 0660

address_pipe:

  driver = pipe

  pipe_as_creator

address_file:

  driver = appendfile

  delivery_date_add

  envelope_to_add

  return_path_add

address_reply:

  driver = autoreply

begin retry

*                      *           F,2h,15m; G,16h,1h,1.5; F,4d,6h

begin rewrite

begin authenticators

You have to add the router and the transport. Router should be placed at the top of the routers stack:

begin routers

ruby:

  driver    = accept

  domains   = domain.tld : another.tld

  transport = ruby_script

. . . . .  

And then a transport - at arbitrary position in the transport list:

begin transports

ruby_script:

  driver  = pipe

  user    = someuser

  command = /path/to/the/script.rb

someuser should have enough permissions to run the script.

Content of the message including all the headers will be passed to the standard input of the script.