usr/src/usr.sbin/sendmail/cf/m4/proto.m4

divert(-1)
#
# Copyright (c) 1983 Eric P. Allman
# Copyright (c) 1988 The Regents of the University of California.
# All rights reserved.
#
# %sccs.include.redist.sh%
#
divert(0)

VERSIONID(@(#)proto.m4  2.4 (Berkeley) %G%)


##################
#   local info   #
##################

ifdef(`_USE_CW_FILE_',
`# file containing internet aliases in our primary domain
Fw/etc/sendmail.cw', `dnl')

ifdef(`UUCP_RELAY',
`# UUCP relay host
CONCAT(DU, UUCP_RELAY)
')dnl
ifdef(`BITNET_RELAY',
`#  BITNET relay host
CONCAT(DB, BITNET_RELAY)
')dnl
ifdef(`CSNET_RELAY',
`# CSNET relay host
CONCAT(DC, CSNET_RELAY)
')dnl
# my official hostname ($w or $w.$D)
Dj$w

# who I masquerade as (can be $j)
CONCAT(DM, ifdef(`MASQUERADE_NAME', MASQUERADE_NAME, $j))

# who I send unqualified names to (null means deliver locally)
CONCAT(DR, ifdef(`LOCAL_RELAY', LOCAL_RELAY))

ifdef(`UUCP_NAME',
`# uucp hostnames
UUCP_NAME
UUCP_ALIASES

# local UUCP connections
include(UUCP_HOSTS_FILE)',
`dnl')

# operators that cannot be in local usernames (i.e., network indicators)
CO @ % !

ifdef(`USERDB_FILE',
`# location of user database file (null means no lookup)
CONCAT(`OU', USERDB_FILE)',
`dnl')

ifdef(`_NO_WILDCARD_MX_',
`# we can guarantee no wildcard MX records matching our domain
Ow',
`dnl')

include(`../m4/version.m4')

ifdef(`INTERNET_RELAY',
`include(../sitedep/nicregistered.m4)',
`dnl')
include(`../m4/boilerplate.m4')
#\f
######################################################################
######################################################################
#####
#####                   REWRITING RULES
#####
######################################################################
######################################################################


###########################################
###  Rulset 3 -- Name Canonicalization  ###
###########################################
S3

# handle "from:<>" special case
R$*<>$*                 $@@                             turn into magic token

# basic textual canonicalization -- note RFC733 heuristic here
R$*<$*<$*<$+>$*>$*>$*   $4                              3-level <> nesting
R$*<$*<$+>$*>$*         $3                              2-level <> nesting
R$*<$+>$*               $2                              basic RFC821/822 parsing

# make sure <@a,@b,@c:user@d> syntax is easy to parse -- undone later
R@$+,$+                 @$1:$2                          change all "," to ":"

# localize and dispose of route-based addresses
R@$+:$+                 $@$>6<@$1>:$2                   handle <route-addr>

# find focus for list syntax
R$+:$*;@$+              $@$>6$1:$2;<@$3>                list syntax
R$+:$*;                 $@$1:$2;                        list syntax

# find focus for @ syntax addresses
R$+@$+                  $:$1<@$2>                       focus on domain
R$+<$+@$+>              $1$2<@$3>                       move gaze right
R$+<@$+>                $@$>6$1<@$2>                    already canonical

# convert old-style addresses to a domain-based address
R$-!$+                  $@$>6$2<@$1.UUCP>               resolve uucp names
R$+.$-!$+               $@$>6$3<@$1.$2>                 domain uucps
R$+!$+                  $@$>6$2<@$1.UUCP>               uucp subdomains

# if we have % signs, take the rightmost one
R$*%$*                  $1@$2                           First make them all @s.
R$*@$*@$*               $1%$2@$3                        Undo all but the last.
R$*@$*                  $@$>6$1<@$2>                    Insert < > and finish

# else we must be a local name


###############################################
###  Ruleset 6 -- bottom half of ruleset 3  ###
###############################################

#  At this point, everything should be in a local_part@domain format.

S6
undivert(2)dnl

# handle special cases for local names
R$*<@$=w>$*             $:$1<@$w>$3                     no domain at all
R$*<@$=w.UUCP>$*        $:$1<@$w>$3                     .UUCP domain

# pass to name server to make hostname canonical
R$* < @ $+ > $*         $: $1 < @ $[ $2 $] > $3         then do anything

# hack to add local domain if nothing sofar has done so
R$* < @ $- > $*         $: $1 < @ $2 @ $w > $3          throw on local host
R$* < @ $- @ $- $* > $* $: $1 < @ $2 $4 > $5            strip host part only


##################################################
###  Ruleset 4 -- Final Output Post-rewriting  ###
##################################################
S4

R@                      $@                              handle <> error addr

# resolve numeric addresses to name if possible
R$*<@[$+]>$*            $:$1<@$[[$2]$]>$3               lookup numeric internet addr

# externalize local domain info
R$*<$+>$*               $1$2$3                          defocus
R@$+:@$+:$+             @$1,@$2:$3                      <route-addr> canonical

# UUCP must always be presented in old form
R$+@$-.UUCP             $2!$1                           u@h.UUCP => h!u

# delete duplicate local names
R$+%$=w@$=w             $1@$w                           u%host@host => u@host


#############################################################
###   Ruleset 7 -- recanonicalize and call ruleset zero   ###
###                (used for recursive calls)             ###
#############################################################

S7
R$*                     $: $>3 $1
R$*                     $@ $>0 $1


######################################
###   Ruleset 0 -- Parse Address   ###
######################################

S0

# handle numeric address spec
R$*<@[$+]>$*            $:$1<@$[[$2]$]>$3               numeric internet addr
R$*<@[$+]>$*            $#smtp$@[$2]$:$1@[$2]$3         numeric internet spec

#R@                     $#error$:Invalid address        handle <> form

# now delete the local info -- note $=O to find characters that cause forwarding
R<@$w>:$*               $@$>7$1                         @here:... -> ...
R$*$=O$*<@$w>           $@$>7$1$2$3                     ...@here -> ...

# short circuit local delivery so forwarded email works
R$+<@$w>                $#local$:$1                     local address

undivert(3)dnl

undivert(4)dnl

# resolve remotely connected UUCP links
R$* < @ $=W . UUCP > $*         $#smtp $@ $W $: $1<@$2.UUCP>$3
R$* < @ $=X . UUCP > $*         $#smtp $@ $X $: $1<@$2.UUCP>$3
R$* < @ $=Y . UUCP > $*         $#smtp $@ $Y $: $1<@$2.UUCP>$3

# resolve fake top level domains by forwarding to other hosts
ifdef(`BITNET_RELAY',
`R$*<@$+.BITNET>$*      $#smtp$@$B$:$1<@$2.BITNET>$3            user@host.BITNET',
        `dnl')
ifdef(`CSNET_RELAY',
`R$*<@$+.CSNET>$*       $#smtp$@$C$:$1<@$2.CSNET>$3             user@host.CSNET',
        `dnl')

ifdef(`UUCP_RELAY',
`# forward non-local UUCP traffic to our UUCP relay
R$*<@$*.UUCP>$*         $#smtp$@$U$:$1<@$2.UUCP>                uucp mail',
`ifdef(`_UUCP_LINKED_',
`# forward other UUCP traffic straight to UUCP
R< @ $+ .UUCP > : $+    $#uucp $@ $1 $: $1:$2                   @host.UUCP:...
R$+ < @ $+ .UUCP>       $#uucp $@ $2 $: $1                      user@host.UUCP',
        `dnl')')

# deal with other remote names
R$* < @ $* > $*         $# smtp $@ $2 $: $1 < @ $2 > $3         user@host.domain

# see if we forward local names
R$=L                    $# local $: $1                  special local names
R$+                     $: $1 @ $R
R$+ @                   $: $1                           no, we don't
R$+ @ $+                $# smtp $@ $2 $: $1             yes, we do

# remaining names must be local
R$+                     $#local$:$1                     everything else

#\f
######################################################################
######################################################################
#####
#####                   MAILER DEFINITIONS
#####
######################################################################
######################################################################

undivert(7)dnl