| 1 | #!/usr/bin/perl |
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| 2 | 'di '; |
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| 3 | 'ds 00 \\"'; |
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| 4 | 'ig 00 '; |
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| 5 | # |
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| 6 | # THIS PROGRAM IS ITS OWN MANUAL PAGE. INSTALL IN man & bin. |
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| 7 | # |
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| 8 | |
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| 9 | use 5.001; |
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| 10 | use IO::Socket; |
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| 11 | |
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| 12 | # system requirements: |
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| 13 | # must have 'nslookup' and 'hostname' programs. |
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| 14 | |
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| 15 | # $OrigHeader: /home/muir/bin/RCS/expn,v 3.11 1997/09/10 08:14:02 muir Exp muir $ |
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| 16 | |
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| 17 | # TODO: |
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| 18 | # less magic should apply to command-line addresses |
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| 19 | # less magic should apply to local addresses |
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| 20 | # add magic to deal with cross-domain cnames |
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| 21 | # disconnect & reconnect after 25 commands to the same sendmail 8.8.* host |
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| 22 | |
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| 23 | # Checklist: (hard addresses) |
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| 24 | # 250 Kimmo Suominen <"|/usr/local/mh/lib/slocal -user kim"@grendel.tac.nyc.ny.us> |
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| 25 | # harry@hofmann.cs.Berkeley.EDU -> harry@tenet (.berkeley.edu) [dead] |
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| 26 | # bks@cs.berkeley.edu -> shiva.CS (.berkeley.edu) [dead] |
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| 27 | # dan@tc.cornell.edu -> brown@tiberius (.tc.cornell.edu) |
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| 28 | |
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| 29 | ############################################################################# |
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| 30 | # |
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| 31 | # Copyright (c) 1993 David Muir Sharnoff |
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| 32 | # All rights reserved. |
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| 33 | # |
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| 34 | # Redistribution and use in source and binary forms, with or without |
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| 35 | # modification, are permitted provided that the following conditions |
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| 36 | # are met: |
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| 37 | # 1. Redistributions of source code must retain the above copyright |
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| 38 | # notice, this list of conditions and the following disclaimer. |
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| 39 | # 2. Redistributions in binary form must reproduce the above copyright |
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| 40 | # notice, this list of conditions and the following disclaimer in the |
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| 41 | # documentation and/or other materials provided with the distribution. |
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| 42 | # 3. All advertising materials mentioning features or use of this software |
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| 43 | # must display the following acknowledgement: |
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| 44 | # This product includes software developed by the David Muir Sharnoff. |
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| 45 | # 4. The name of David Sharnoff may not be used to endorse or promote products |
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| 46 | # derived from this software without specific prior written permission. |
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| 47 | # |
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| 48 | # THIS SOFTWARE IS PROVIDED BY THE DAVID MUIR SHARNOFF ``AS IS'' AND |
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| 49 | # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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| 50 | # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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| 51 | # ARE DISCLAIMED. IN NO EVENT SHALL DAVID MUIR SHARNOFF BE LIABLE |
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| 52 | # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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| 53 | # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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| 54 | # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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| 55 | # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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| 56 | # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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| 57 | # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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| 58 | # SUCH DAMAGE. |
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| 59 | # |
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| 60 | # This copyright notice derrived from material copyrighted by the Regents |
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| 61 | # of the University of California. |
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| 62 | # |
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| 63 | # Contributions accepted. |
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| 64 | # |
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| 65 | ############################################################################# |
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| 66 | |
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| 67 | # overall structure: |
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| 68 | # in an effort to not trace each address individually, but rather |
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| 69 | # ask each server in turn a whole bunch of questions, addresses to |
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| 70 | # be expanded are queued up. |
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| 71 | # |
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| 72 | # This means that all accounting w.r.t. an address must be stored in |
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| 73 | # various arrays. Generally these arrays are indexed by the |
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| 74 | # string "$addr *** $server" where $addr is the address to be |
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| 75 | # expanded "foo" or maybe "foo@bar" and $server is the hostname |
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| 76 | # of the SMTP server to contact. |
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| 77 | # |
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| 78 | |
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| 79 | # important global variables: |
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| 80 | # |
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| 81 | # @hosts : list of servers still to be contacted |
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| 82 | # $server : name of the current we are currently looking at |
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| 83 | # @users = $users{@hosts[0]} : addresses to expand at this server |
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| 84 | # $u = $users[0] : the current address being expanded |
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| 85 | # $names{"$users[0] *** $server"} : the 'name' associated with the address |
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| 86 | # $mxbacktrace{"$users[0] *** $server"} : record of mx expansion |
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| 87 | # $mx_secondary{$server} : other mx relays at the same priority |
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| 88 | # $domainify_fallback{"$users[0] *** $server"} : alternative names to try |
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| 89 | # instead of $server if $server doesn't work |
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| 90 | # $temporary_redirect{"$users[0] *** $server"} : when trying alternates, |
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| 91 | # temporarily channel all tries along current path |
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| 92 | # $giveup{$server} : do not bother expanding addresses at $server |
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| 93 | # $verbose : -v |
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| 94 | # $watch : -w |
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| 95 | # $vw : -v or -w |
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| 96 | # $debug : -d |
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| 97 | # $valid : -a |
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| 98 | # $levels : -1 |
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| 99 | # $S : the socket connection to $server |
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| 100 | |
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| 101 | $have_nslookup = 1; # we have the nslookup program |
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| 102 | $port = 'smtp'; |
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| 103 | $av0 = $0; |
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| 104 | $ENV{'PATH'} .= ":/usr/etc" unless $ENV{'PATH'} =~ m,/usr/etc,; |
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| 105 | $ENV{'PATH'} .= ":/usr/ucb" unless $ENV{'PATH'} =~ m,/usr/ucb,; |
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| 106 | select(STDERR); |
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| 107 | |
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| 108 | $0 = "$av0 - running hostname"; |
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| 109 | chop($name = `hostname || uname -n`); |
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| 110 | |
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| 111 | $0 = "$av0 - lookup host FQDN and IP addr"; |
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| 112 | ($hostname,$aliases,$type,$len,$thisaddr) = gethostbyname($name); |
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| 113 | |
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| 114 | $0 = "$av0 - parsing args"; |
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| 115 | $usage = "Usage: $av0 [-1avwd] user[\@host] [user2[host2] ...]"; |
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| 116 | for $a (@ARGV) { |
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| 117 | die $usage if $a eq "-"; |
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| 118 | while ($a =~ s/^(-.*)([1avwd])/$1/) { |
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| 119 | eval '$'."flag_$2 += 1"; |
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| 120 | } |
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| 121 | next if $a eq "-"; |
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| 122 | die $usage if $a =~ /^-/; |
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| 123 | &expn(&parse($a,$hostname,undef,1)); |
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| 124 | } |
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| 125 | $verbose = $flag_v; |
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| 126 | $watch = $flag_w; |
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| 127 | $vw = $flag_v + $flag_w; |
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| 128 | $debug = $flag_d; |
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| 129 | $valid = $flag_a; |
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| 130 | $levels = $flag_1; |
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| 131 | |
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| 132 | die $usage unless @hosts; |
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| 133 | if ($valid) { |
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| 134 | if ($valid == 1) { |
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| 135 | $validRequirement = 0.8; |
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| 136 | } elsif ($valid == 2) { |
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| 137 | $validRequirement = 1.0; |
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| 138 | } elsif ($valid == 3) { |
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| 139 | $validRequirement = 0.9; |
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| 140 | } else { |
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| 141 | $validRequirement = (1 - (1/($valid-3))); |
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| 142 | print "validRequirement = $validRequirement\n" if $debug; |
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| 143 | } |
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| 144 | } |
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| 145 | |
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| 146 | HOST: |
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| 147 | while (@hosts) { |
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| 148 | $server = shift(@hosts); |
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| 149 | @users = split(' ',$users{$server}); |
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| 150 | delete $users{$server}; |
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| 151 | |
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| 152 | # is this server already known to be bad? |
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| 153 | $0 = "$av0 - looking up $server"; |
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| 154 | if ($giveup{$server}) { |
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| 155 | &giveup('mx domainify',$giveup{$server}); |
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| 156 | next; |
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| 157 | } |
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| 158 | |
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| 159 | # do we already have an mx record for this host? |
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| 160 | next HOST if &mxredirect($server,*users); |
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| 161 | |
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| 162 | # look it up, or try for an mx. |
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| 163 | $0 = "$av0 - gethostbyname($server)"; |
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| 164 | |
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| 165 | ($name,$aliases,$type,$len,$thataddr) = gethostbyname($server); |
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| 166 | # if we can't get an A record, try for an MX record. |
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| 167 | unless($thataddr) { |
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| 168 | &mxlookup(1,$server,"$server: could not resolve name",*users); |
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| 169 | next HOST; |
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| 170 | } |
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| 171 | |
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| 172 | # get a connection, or look for an mx |
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| 173 | $0 = "$av0 - socket to $server"; |
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| 174 | |
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| 175 | $S = new IO::Socket::INET ( |
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| 176 | 'PeerAddr' => $server, |
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| 177 | 'PeerPort' => $port, |
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| 178 | 'Proto' => 'tcp'); |
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| 179 | |
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| 180 | if (! $S || ($debug == 10 && $server =~ /relay\d.UU.NET$/i)) { |
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| 181 | $0 = "$av0 - $server: could not connect: $!\n"; |
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| 182 | $emsg = $!; |
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| 183 | unless (&mxlookup(0,$server,"$server: could not connect: $!",*users)) { |
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| 184 | &giveup('mx',"$server: Could not connect: $emsg"); |
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| 185 | } |
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| 186 | next HOST; |
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| 187 | } |
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| 188 | $S->autoflush(1); |
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| 189 | |
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| 190 | # read the greeting |
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| 191 | $0 = "$av0 - talking to $server"; |
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| 192 | &alarm("greeting with $server",''); |
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| 193 | while(<$S>) { |
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| 194 | alarm(0); |
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| 195 | print if $watch; |
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| 196 | if (/^(\d+)([- ])/) { |
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| 197 | if ($1 != 220) { |
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| 198 | $0 = "$av0 - bad numeric response from $server"; |
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| 199 | &alarm("giving up after bad response from $server",''); |
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| 200 | &read_response($2,$watch); |
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| 201 | alarm(0); |
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| 202 | print STDERR "$server: NOT 220 greeting: $_" |
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| 203 | if ($debug || $vw); |
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| 204 | if (&mxlookup(0,$server,"$server: did not respond with a 220 greeting",*users)) { |
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| 205 | close($S); |
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| 206 | next HOST; |
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| 207 | } |
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| 208 | } |
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| 209 | last if ($2 eq " "); |
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| 210 | } else { |
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| 211 | $0 = "$av0 - bad response from $server"; |
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| 212 | print STDERR "$server: NOT 220 greeting: $_" |
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| 213 | if ($debug || $vw); |
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| 214 | unless (&mxlookup(0,$server,"$server: did not respond with SMTP codes",*users)) { |
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| 215 | &giveup('',"$server: did not talk SMTP"); |
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| 216 | } |
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| 217 | close($S); |
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| 218 | next HOST; |
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| 219 | } |
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| 220 | &alarm("greeting with $server",''); |
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| 221 | } |
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| 222 | alarm(0); |
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| 223 | |
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| 224 | # if this causes problems, remove it |
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| 225 | $0 = "$av0 - sending helo to $server"; |
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| 226 | &alarm("sending helo to $server",""); |
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| 227 | &ps("helo $hostname"); |
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| 228 | while(<$S>) { |
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| 229 | print if $watch; |
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| 230 | last if /^\d+ /; |
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| 231 | } |
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| 232 | alarm(0); |
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| 233 | |
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| 234 | # try the users, one by one |
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| 235 | USER: |
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| 236 | while(@users) { |
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| 237 | $u = shift(@users); |
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| 238 | $0 = "$av0 - expanding $u [\@$server]"; |
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| 239 | |
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| 240 | # do we already have a name for this user? |
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| 241 | $oldname = $names{"$u *** $server"}; |
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| 242 | |
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| 243 | print &compact($u,$server)." ->\n" if ($verbose && ! $valid); |
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| 244 | if ($valid) { |
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| 245 | # |
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| 246 | # when running with -a, we delay taking any action |
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| 247 | # on the results of our query until we have looked |
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| 248 | # at the complete output. @toFinal stores expansions |
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| 249 | # that will be final if we take them. @toExpn stores |
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| 250 | # expnansions that are not final. @isValid keeps |
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| 251 | # track of our ability to send mail to each of the |
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| 252 | # expansions. |
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| 253 | # |
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| 254 | @isValid = (); |
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| 255 | @toFinal = (); |
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| 256 | @toExpn = (); |
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| 257 | } |
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| 258 | |
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| 259 | # ($ecode,@expansion) = &expn_vrfy($u,$server); |
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| 260 | (@foo) = &expn_vrfy($u,$server); |
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| 261 | ($ecode,@expansion) = @foo; |
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| 262 | if ($ecode) { |
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| 263 | &giveup('',$ecode,$u); |
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| 264 | last USER; |
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| 265 | } |
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| 266 | |
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| 267 | for $s (@expansion) { |
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| 268 | $s =~ s/[\n\r]//g; |
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| 269 | $0 = "$av0 - parsing $server: $s"; |
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| 270 | |
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| 271 | $skipwatch = $watch; |
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| 272 | |
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| 273 | if ($s =~ /^[25]51([- ]).*<(.+)>/) { |
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| 274 | print "$s" if $watch; |
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| 275 | print "(pretending 250$1<$2>)" if ($debug && $watch); |
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| 276 | print "\n" if $watch; |
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| 277 | $s = "250$1<$2>"; |
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| 278 | $skipwatch = 0; |
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| 279 | } |
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| 280 | |
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| 281 | if ($s =~ /^250([- ])(.+)/) { |
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| 282 | print "$s\n" if $skipwatch; |
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| 283 | ($done,$addr) = ($1,$2); |
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| 284 | ($newhost, $newaddr, $newname) = &parse($addr,$server,$oldname, $#expansion == 0); |
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| 285 | print "($newhost, $newaddr, $newname) = &parse($addr, $server, $oldname)\n" if $debug; |
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| 286 | if (! $newhost) { |
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| 287 | # no expansion is possible w/o a new server to call |
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| 288 | if ($valid) { |
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| 289 | push(@isValid, &validAddr($newaddr)); |
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| 290 | push(@toFinal,$newaddr,$server,$newname); |
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| 291 | } else { |
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| 292 | &verbose(&final($newaddr,$server,$newname)); |
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| 293 | } |
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| 294 | } else { |
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| 295 | $newmxhost = &mx($newhost,$newaddr); |
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| 296 | print "$newmxhost = &mx($newhost)\n" |
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| 297 | if ($debug && $newhost ne $newmxhost); |
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| 298 | $0 = "$av0 - parsing $newaddr [@$newmxhost]"; |
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| 299 | print "levels = $levels, level{$u *** $server} = ".$level{"$u *** $server"}."\n" if ($debug > 1); |
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| 300 | # If the new server is the current one, |
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| 301 | # it would have expanded things for us |
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| 302 | # if it could have. Mx records must be |
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| 303 | # followed to compare server names. |
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| 304 | # We are also done if the recursion |
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| 305 | # count has been exceeded. |
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| 306 | if (&trhost($newmxhost) eq &trhost($server) || ($levels && $level{"$u *** $server"} >= $levels)) { |
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| 307 | if ($valid) { |
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| 308 | push(@isValid, &validAddr($newaddr)); |
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| 309 | push(@toFinal,$newaddr,$newmxhost,$newname); |
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| 310 | } else { |
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| 311 | &verbose(&final($newaddr,$newmxhost,$newname)); |
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| 312 | } |
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| 313 | } else { |
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| 314 | # more work to do... |
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| 315 | if ($valid) { |
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| 316 | push(@isValid, &validAddr($newaddr)); |
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| 317 | push(@toExpn,$newmxhost,$newaddr,$newname,$level{"$u *** $server"}); |
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| 318 | } else { |
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| 319 | &verbose(&expn($newmxhost,$newaddr,$newname,$level{"$u *** $server"})); |
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| 320 | } |
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| 321 | } |
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| 322 | } |
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| 323 | last if ($done eq " "); |
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| 324 | next; |
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| 325 | } |
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| 326 | # 550 is a known code... Should the be |
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| 327 | # included in -a output? Might be a bug |
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| 328 | # here. Does it matter? Can assume that |
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| 329 | # there won't be UNKNOWN USER responses |
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| 330 | # mixed with valid users? |
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| 331 | if ($s =~ /^(550)([- ])/) { |
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| 332 | if ($valid) { |
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| 333 | print STDERR "\@$server:$u ($oldname) USER UNKNOWN\n"; |
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| 334 | } else { |
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| 335 | &verbose(&final($u,$server,$oldname,"USER UNKNOWN")); |
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| 336 | } |
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| 337 | last if ($2 eq " "); |
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| 338 | next; |
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| 339 | } |
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| 340 | # 553 is a known code... |
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| 341 | if ($s =~ /^(553)([- ])/) { |
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| 342 | if ($valid) { |
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| 343 | print STDERR "\@$server:$u ($oldname) USER AMBIGUOUS\n"; |
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| 344 | } else { |
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| 345 | &verbose(&final($u,$server,$oldname,"USER AMBIGUOUS")); |
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| 346 | } |
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| 347 | last if ($2 eq " "); |
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| 348 | next; |
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| 349 | } |
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| 350 | # 252 is a known code... |
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| 351 | if ($s =~ /^(252)([- ])/) { |
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| 352 | if ($valid) { |
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| 353 | print STDERR "\@$server:$u ($oldname) REFUSED TO VRFY\n"; |
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| 354 | } else { |
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| 355 | &verbose(&final($u,$server,$oldname,"REFUSED TO VRFY")); |
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| 356 | } |
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| 357 | last if ($2 eq " "); |
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| 358 | next; |
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| 359 | } |
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| 360 | &giveup('',"$server: did not grok '$s'",$u); |
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| 361 | last USER; |
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| 362 | } |
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| 363 | |
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| 364 | if ($valid) { |
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| 365 | # |
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| 366 | # now we decide if we are going to take these |
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| 367 | # expansions or roll them back. |
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| 368 | # |
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| 369 | $avgValid = &average(@isValid); |
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| 370 | print "avgValid = $avgValid\n" if $debug; |
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| 371 | if ($avgValid >= $validRequirement) { |
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| 372 | print &compact($u,$server)." ->\n" if $verbose; |
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| 373 | while (@toExpn) { |
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| 374 | &verbose(&expn(splice(@toExpn,0,4))); |
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| 375 | } |
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| 376 | while (@toFinal) { |
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| 377 | &verbose(&final(splice(@toFinal,0,3))); |
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| 378 | } |
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| 379 | } else { |
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| 380 | print "Tossing some valid to avoid invalid ".&compact($u,$server)."\n" if ($avgValid > 0.0 && ($vw || $debug)); |
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| 381 | print &compact($u,$server)." ->\n" if $verbose; |
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| 382 | &verbose(&final($u,$server,$newname)); |
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| 383 | } |
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| 384 | } |
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| 385 | } |
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| 386 | |
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| 387 | &alarm("sending 'quit' to $server",''); |
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| 388 | $0 = "$av0 - sending 'quit' to $server"; |
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| 389 | &ps("quit"); |
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| 390 | while(<$S>) { |
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| 391 | print if $watch; |
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| 392 | last if /^\d+ /; |
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| 393 | } |
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| 394 | close($S); |
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| 395 | alarm(0); |
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| 396 | } |
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| 397 | |
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| 398 | $0 = "$av0 - printing final results"; |
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| 399 | print "----------\n" if $vw; |
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| 400 | select(STDOUT); |
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| 401 | for $f (sort @final) { |
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| 402 | print "$f\n"; |
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| 403 | } |
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| 404 | unlink("/tmp/expn$$"); |
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| 405 | exit(0); |
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| 406 | |
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| 407 | |
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| 408 | # abandon all attempts deliver to $server |
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| 409 | # register the current addresses as the final ones |
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| 410 | sub giveup |
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| 411 | { |
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| 412 | local($redirect_okay,$reason,$user) = @_; |
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| 413 | local($us,@so,$nh,@remaining_users); |
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| 414 | local($pk,$file,$line); |
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| 415 | ($pk, $file, $line) = caller; |
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| 416 | |
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| 417 | $0 = "$av0 - giving up on $server: $reason"; |
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| 418 | # |
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| 419 | # add back a user if we gave up in the middle |
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| 420 | # |
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| 421 | push(@users,$user) if $user; |
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| 422 | # |
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| 423 | # don't bother with this system anymore |
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| 424 | # |
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| 425 | unless ($giveup{$server}) { |
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| 426 | $giveup{$server} = $reason; |
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| 427 | print STDERR "$reason\n"; |
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| 428 | } |
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| 429 | print "Giveup at $file:$line!!! redirect okay = $redirect_okay; $reason\n" if $debug; |
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| 430 | # |
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| 431 | # Wait! |
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| 432 | # Before giving up, see if there is a chance that |
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| 433 | # there is another host to redirect to! |
|---|
| 434 | # (Kids, don't do this at home! Hacking is a dangerous |
|---|
| 435 | # crime and you could end up behind bars.) |
|---|
| 436 | # |
|---|
| 437 | for $u (@users) { |
|---|
| 438 | if ($redirect_okay =~ /\bmx\b/) { |
|---|
| 439 | next if &try_fallback('mx',$u,*server, |
|---|
| 440 | *mx_secondary, |
|---|
| 441 | *already_mx_fellback); |
|---|
| 442 | } |
|---|
| 443 | if ($redirect_okay =~ /\bdomainify\b/) { |
|---|
| 444 | next if &try_fallback('domainify',$u,*server, |
|---|
| 445 | *domainify_fallback, |
|---|
| 446 | *already_domainify_fellback); |
|---|
| 447 | } |
|---|
| 448 | push(@remaining_users,$u); |
|---|
| 449 | } |
|---|
| 450 | @users = @remaining_users; |
|---|
| 451 | for $u (@users) { |
|---|
| 452 | print &compact($u,$server)." ->\n" if ($verbose && $valid && $u); |
|---|
| 453 | &verbose(&final($u,$server,$names{"$u *** $server"},$reason)); |
|---|
| 454 | } |
|---|
| 455 | } |
|---|
| 456 | # |
|---|
| 457 | # This routine is used only within &giveup. It checks to |
|---|
| 458 | # see if we really have to giveup or if there is a second |
|---|
| 459 | # chance because we did something before that can be |
|---|
| 460 | # backtracked. |
|---|
| 461 | # |
|---|
| 462 | # %fallback{"$user *** $host"} tracks what is able to fallback |
|---|
| 463 | # %fellback{"$user *** $host"} tracks what has fallen back |
|---|
| 464 | # |
|---|
| 465 | # If there is a valid backtrack, then queue up the new possibility |
|---|
| 466 | # |
|---|
| 467 | sub try_fallback |
|---|
| 468 | { |
|---|
| 469 | local($method,$user,*host,*fall_table,*fellback) = @_; |
|---|
| 470 | local($us,$fallhost,$oldhost,$ft,$i); |
|---|
| 471 | |
|---|
| 472 | if ($debug > 8) { |
|---|
| 473 | print "Fallback table $method:\n"; |
|---|
| 474 | for $i (sort keys %fall_table) { |
|---|
| 475 | print "\t'$i'\t\t'$fall_table{$i}'\n"; |
|---|
| 476 | } |
|---|
| 477 | print "Fellback table $method:\n"; |
|---|
| 478 | for $i (sort keys %fellback) { |
|---|
| 479 | print "\t'$i'\t\t'$fellback{$i}'\n"; |
|---|
| 480 | } |
|---|
| 481 | print "U: $user H: $host\n"; |
|---|
| 482 | } |
|---|
| 483 | |
|---|
| 484 | $us = "$user *** $host"; |
|---|
| 485 | if (defined $fellback{$us}) { |
|---|
| 486 | # |
|---|
| 487 | # Undo a previous fallback so that we can try again |
|---|
| 488 | # Nested fallbacks are avoided because they could |
|---|
| 489 | # lead to infinite loops |
|---|
| 490 | # |
|---|
| 491 | $fallhost = $fellback{$us}; |
|---|
| 492 | print "Already $method fell back from $us -> \n" if $debug; |
|---|
| 493 | $us = "$user *** $fallhost"; |
|---|
| 494 | $oldhost = $fallhost; |
|---|
| 495 | } elsif (($method eq 'mx') && (defined $mxbacktrace{$us}) && (defined $mx_secondary{$mxbacktrace{$us}})) { |
|---|
| 496 | print "Fallback an MX expansion $us -> \n" if $debug; |
|---|
| 497 | $oldhost = $mxbacktrace{$us}; |
|---|
| 498 | } else { |
|---|
| 499 | print "Oldhost($host, $us) = " if $debug; |
|---|
| 500 | $oldhost = $host; |
|---|
| 501 | } |
|---|
| 502 | print "$oldhost\n" if $debug; |
|---|
| 503 | if (((defined $fall_table{$us}) && ($ft = $us)) || ((defined $fall_table{$oldhost}) && ($ft = $oldhost))) { |
|---|
| 504 | print "$method Fallback = ".$fall_table{$ft}."\n" if $debug; |
|---|
| 505 | local(@so,$newhost); |
|---|
| 506 | @so = split(' ',$fall_table{$ft}); |
|---|
| 507 | $newhost = shift(@so); |
|---|
| 508 | print "Falling back ($method) $us -> $newhost (from $oldhost)\n" if $debug; |
|---|
| 509 | if ($method eq 'mx') { |
|---|
| 510 | if (! defined ($mxbacktrace{"$user *** $newhost"})) { |
|---|
| 511 | if (defined $mxbacktrace{"$user *** $oldhost"}) { |
|---|
| 512 | print "resetting oldhost $oldhost to the original: " if $debug; |
|---|
| 513 | $oldhost = $mxbacktrace{"$user *** $oldhost"}; |
|---|
| 514 | print "$oldhost\n" if $debug; |
|---|
| 515 | } |
|---|
| 516 | $mxbacktrace{"$user *** $newhost"} = $oldhost; |
|---|
| 517 | print "mxbacktrace $user *** $newhost -> $oldhost\n" if $debug; |
|---|
| 518 | } |
|---|
| 519 | $mx{&trhost($oldhost)} = $newhost; |
|---|
| 520 | } else { |
|---|
| 521 | $temporary_redirect{$us} = $newhost; |
|---|
| 522 | } |
|---|
| 523 | if (@so) { |
|---|
| 524 | print "Can still $method $us: @so\n" if $debug; |
|---|
| 525 | $fall_table{$ft} = join(' ',@so); |
|---|
| 526 | } else { |
|---|
| 527 | print "No more fallbacks for $us\n" if $debug; |
|---|
| 528 | delete $fall_table{$ft}; |
|---|
| 529 | } |
|---|
| 530 | if (defined $create_host_backtrack{$us}) { |
|---|
| 531 | $create_host_backtrack{"$user *** $newhost"} |
|---|
| 532 | = $create_host_backtrack{$us}; |
|---|
| 533 | } |
|---|
| 534 | $fellback{"$user *** $newhost"} = $oldhost; |
|---|
| 535 | &expn($newhost,$user,$names{$us},$level{$us}); |
|---|
| 536 | return 1; |
|---|
| 537 | } |
|---|
| 538 | delete $temporary_redirect{$us}; |
|---|
| 539 | $host = $oldhost; |
|---|
| 540 | return 0; |
|---|
| 541 | } |
|---|
| 542 | # return 1 if you could send mail to the address as is. |
|---|
| 543 | sub validAddr |
|---|
| 544 | { |
|---|
| 545 | local($addr) = @_; |
|---|
| 546 | $res = &do_validAddr($addr); |
|---|
| 547 | print "validAddr($addr) = $res\n" if $debug; |
|---|
| 548 | $res; |
|---|
| 549 | } |
|---|
| 550 | sub do_validAddr |
|---|
| 551 | { |
|---|
| 552 | local($addr) = @_; |
|---|
| 553 | local($urx) = "[-A-Za-z_.0-9+]+"; |
|---|
| 554 | |
|---|
| 555 | # \u |
|---|
| 556 | return 0 if ($addr =~ /^\\/); |
|---|
| 557 | # ?@h |
|---|
| 558 | return 1 if ($addr =~ /.\@$urx$/); |
|---|
| 559 | # @h:? |
|---|
| 560 | return 1 if ($addr =~ /^\@$urx\:./); |
|---|
| 561 | # h!u |
|---|
| 562 | return 1 if ($addr =~ /^$urx!./); |
|---|
| 563 | # u |
|---|
| 564 | return 1 if ($addr =~ /^$urx$/); |
|---|
| 565 | # ? |
|---|
| 566 | print "validAddr($addr) = ???\n" if $debug; |
|---|
| 567 | return 0; |
|---|
| 568 | } |
|---|
| 569 | # Some systems use expn and vrfy interchangeably. Some only |
|---|
| 570 | # implement one or the other. Some check expn against mailing |
|---|
| 571 | # lists and vrfy against users. It doesn't appear to be |
|---|
| 572 | # consistent. |
|---|
| 573 | # |
|---|
| 574 | # So, what do we do? We try everything! |
|---|
| 575 | # |
|---|
| 576 | # |
|---|
| 577 | # Ranking of result codes: good: 250, 251/551, 252, 550, anything else |
|---|
| 578 | # |
|---|
| 579 | # Ranking of inputs: best: user@host.domain, okay: user |
|---|
| 580 | # |
|---|
| 581 | # Return value: $error_string, @responses_from_server |
|---|
| 582 | sub expn_vrfy |
|---|
| 583 | { |
|---|
| 584 | local($u,$server) = @_; |
|---|
| 585 | local(@c) = ('expn', 'vrfy'); |
|---|
| 586 | local(@try_u) = $u; |
|---|
| 587 | local(@ret,$code); |
|---|
| 588 | |
|---|
| 589 | if (($u =~ /(.+)@(.+)/) && (&trhost($2) eq &trhost($server))) { |
|---|
| 590 | push(@try_u,$1); |
|---|
| 591 | } |
|---|
| 592 | |
|---|
| 593 | TRY: |
|---|
| 594 | for $c (@c) { |
|---|
| 595 | for $try_u (@try_u) { |
|---|
| 596 | &alarm("${c}'ing $try_u on $server",'',$u); |
|---|
| 597 | &ps("$c $try_u"); |
|---|
| 598 | alarm(0); |
|---|
| 599 | $s = <$S>; |
|---|
| 600 | if ($s eq '') { |
|---|
| 601 | return "$server: lost connection"; |
|---|
| 602 | } |
|---|
| 603 | if ($s !~ /^(\d+)([- ])/) { |
|---|
| 604 | return "$server: garbled reply to '$c $try_u'"; |
|---|
| 605 | } |
|---|
| 606 | if ($1 == 250) { |
|---|
| 607 | $code = 250; |
|---|
| 608 | @ret = ("",$s); |
|---|
| 609 | push(@ret,&read_response($2,$debug)); |
|---|
| 610 | return (@ret); |
|---|
| 611 | } |
|---|
| 612 | if ($1 == 551 || $1 == 251) { |
|---|
| 613 | $code = $1; |
|---|
| 614 | @ret = ("",$s); |
|---|
| 615 | push(@ret,&read_response($2,$debug)); |
|---|
| 616 | next; |
|---|
| 617 | } |
|---|
| 618 | if ($1 == 252 && ($code == 0 || $code == 550)) { |
|---|
| 619 | $code = 252; |
|---|
| 620 | @ret = ("",$s); |
|---|
| 621 | push(@ret,&read_response($2,$watch)); |
|---|
| 622 | next; |
|---|
| 623 | } |
|---|
| 624 | if ($1 == 550 && $code == 0) { |
|---|
| 625 | $code = 550; |
|---|
| 626 | @ret = ("",$s); |
|---|
| 627 | push(@ret,&read_response($2,$watch)); |
|---|
| 628 | next; |
|---|
| 629 | } |
|---|
| 630 | &read_response($2,$watch); |
|---|
| 631 | } |
|---|
| 632 | } |
|---|
| 633 | return "$server: expn/vrfy not implemented" unless @ret; |
|---|
| 634 | return @ret; |
|---|
| 635 | } |
|---|
| 636 | # sometimes the old parse routine (now parse2) didn't |
|---|
| 637 | # reject funky addresses. |
|---|
| 638 | sub parse |
|---|
| 639 | { |
|---|
| 640 | local($oldaddr,$server,$oldname,$one_to_one) = @_; |
|---|
| 641 | local($newhost, $newaddr, $newname, $um) = &parse2($oldaddr,$server,$oldname,$one_to_one); |
|---|
| 642 | if ($newaddr =~ m,^["/],) { |
|---|
| 643 | return (undef, $oldaddr, $newname) if $valid; |
|---|
| 644 | return (undef, $um, $newname); |
|---|
| 645 | } |
|---|
| 646 | return ($newhost, $newaddr, $newname); |
|---|
| 647 | } |
|---|
| 648 | |
|---|
| 649 | # returns ($new_smtp_server,$new_address,$new_name) |
|---|
| 650 | # given a response from a SMTP server ($newaddr), the |
|---|
| 651 | # current host ($server), the old "name" and a flag that |
|---|
| 652 | # indicates if it is being called during the initial |
|---|
| 653 | # command line parsing ($parsing_args) |
|---|
| 654 | sub parse2 |
|---|
| 655 | { |
|---|
| 656 | local($newaddr,$context_host,$old_name,$parsing_args) = @_; |
|---|
| 657 | local(@names) = $old_name; |
|---|
| 658 | local($urx) = "[-A-Za-z_.0-9+]+"; |
|---|
| 659 | local($unmangle); |
|---|
| 660 | |
|---|
| 661 | # |
|---|
| 662 | # first, separate out the address part. |
|---|
| 663 | # |
|---|
| 664 | |
|---|
| 665 | # |
|---|
| 666 | # [NAME] <ADDR [(NAME)]> |
|---|
| 667 | # [NAME] <[(NAME)] ADDR |
|---|
| 668 | # ADDR [(NAME)] |
|---|
| 669 | # (NAME) ADDR |
|---|
| 670 | # [(NAME)] <ADDR> |
|---|
| 671 | # |
|---|
| 672 | if ($newaddr =~ /^\<(.*)\>$/) { |
|---|
| 673 | print "<A:$1>\n" if $debug; |
|---|
| 674 | ($newaddr) = &trim($1); |
|---|
| 675 | print "na = $newaddr\n" if $debug; |
|---|
| 676 | } |
|---|
| 677 | if ($newaddr =~ /^([^\<\>]*)\<([^\<\>]*)\>([^\<\>]*)$/) { |
|---|
| 678 | # address has a < > pair in it. |
|---|
| 679 | print "N:$1 <A:$2> N:$3\n" if $debug; |
|---|
| 680 | ($newaddr) = &trim($2); |
|---|
| 681 | unshift(@names, &trim($3,$1)); |
|---|
| 682 | print "na = $newaddr\n" if $debug; |
|---|
| 683 | } |
|---|
| 684 | if ($newaddr =~ /^([^\(\)]*)\(([^\(\)]*)\)([^\(\)]*)$/) { |
|---|
| 685 | # address has a ( ) pair in it. |
|---|
| 686 | print "A:$1 (N:$2) A:$3\n" if $debug; |
|---|
| 687 | unshift(@names,&trim($2)); |
|---|
| 688 | local($f,$l) = (&trim($1),&trim($3)); |
|---|
| 689 | if (($f && $l) || !($f || $l)) { |
|---|
| 690 | # address looks like: |
|---|
| 691 | # foo (bar) baz or (bar) |
|---|
| 692 | # not allowed! |
|---|
| 693 | print STDERR "Could not parse $newaddr\n" if $vw; |
|---|
| 694 | return(undef,$newaddr,&firstname(@names)); |
|---|
| 695 | } |
|---|
| 696 | $newaddr = $f if $f; |
|---|
| 697 | $newaddr = $l if $l; |
|---|
| 698 | print "newaddr now = $newaddr\n" if $debug; |
|---|
| 699 | } |
|---|
| 700 | # |
|---|
| 701 | # @foo:bar |
|---|
| 702 | # j%k@l |
|---|
| 703 | # a@b |
|---|
| 704 | # b!a |
|---|
| 705 | # a |
|---|
| 706 | # |
|---|
| 707 | $unmangle = $newaddr; |
|---|
| 708 | if ($newaddr =~ /^\@($urx)\:(.+)$/) { |
|---|
| 709 | print "(\@:)" if $debug; |
|---|
| 710 | # this is a bit of a cheat, but it seems necessary |
|---|
| 711 | return (&domainify($1,$context_host,$2),$2,&firstname(@names),$unmangle); |
|---|
| 712 | } |
|---|
| 713 | if ($newaddr =~ /^(.+)\@($urx)$/) { |
|---|
| 714 | print "(\@)" if $debug; |
|---|
| 715 | return (&domainify($2,$context_host,$newaddr),$newaddr,&firstname(@names),$unmangle); |
|---|
| 716 | } |
|---|
| 717 | if ($parsing_args) { |
|---|
| 718 | if ($newaddr =~ /^($urx)\!(.+)$/) { |
|---|
| 719 | return (&domainify($1,$context_host,$newaddr),$newaddr,&firstname(@names),$unmangle); |
|---|
| 720 | } |
|---|
| 721 | if ($newaddr =~ /^($urx)$/) { |
|---|
| 722 | return ($context_host,$newaddr,&firstname(@names),$unmangle); |
|---|
| 723 | } |
|---|
| 724 | print STDERR "Could not parse $newaddr\n"; |
|---|
| 725 | } |
|---|
| 726 | print "(?)" if $debug; |
|---|
| 727 | return(undef,$newaddr,&firstname(@names),$unmangle); |
|---|
| 728 | } |
|---|
| 729 | # return $u (@$server) unless $u includes reference to $server |
|---|
| 730 | sub compact |
|---|
| 731 | { |
|---|
| 732 | local($u, $server) = @_; |
|---|
| 733 | local($se) = $server; |
|---|
| 734 | local($sp); |
|---|
| 735 | $se =~ s/(\W)/\\$1/g; |
|---|
| 736 | $sp = " (\@$server)"; |
|---|
| 737 | if ($u !~ /$se/i) { |
|---|
| 738 | return "$u$sp"; |
|---|
| 739 | } |
|---|
| 740 | return $u; |
|---|
| 741 | } |
|---|
| 742 | # remove empty (spaces don't count) members from an array |
|---|
| 743 | sub trim |
|---|
| 744 | { |
|---|
| 745 | local(@v) = @_; |
|---|
| 746 | local($v,@r); |
|---|
| 747 | for $v (@v) { |
|---|
| 748 | $v =~ s/^\s+//; |
|---|
| 749 | $v =~ s/\s+$//; |
|---|
| 750 | push(@r,$v) if ($v =~ /\S/); |
|---|
| 751 | } |
|---|
| 752 | return(@r); |
|---|
| 753 | } |
|---|
| 754 | # using the host part of an address, and the server name, add the |
|---|
| 755 | # servers' domain to the address if it doesn't already have a |
|---|
| 756 | # domain. Since this sometimes fails, save a back reference so |
|---|
| 757 | # it can be unrolled. |
|---|
| 758 | sub domainify |
|---|
| 759 | { |
|---|
| 760 | local($host,$domain_host,$u) = @_; |
|---|
| 761 | local($domain,$newhost); |
|---|
| 762 | |
|---|
| 763 | # cut of trailing dots |
|---|
| 764 | $host =~ s/\.$//; |
|---|
| 765 | $domain_host =~ s/\.$//; |
|---|
| 766 | |
|---|
| 767 | if ($domain_host !~ /\./) { |
|---|
| 768 | # |
|---|
| 769 | # domain host isn't, keep $host whatever it is |
|---|
| 770 | # |
|---|
| 771 | print "domainify($host,$domain_host) = $host\n" if $debug; |
|---|
| 772 | return $host; |
|---|
| 773 | } |
|---|
| 774 | |
|---|
| 775 | # |
|---|
| 776 | # There are several weird situtations that need to be |
|---|
| 777 | # accounted for. They have to do with domain relay hosts. |
|---|
| 778 | # |
|---|
| 779 | # Examples: |
|---|
| 780 | # host server "right answer" |
|---|
| 781 | # |
|---|
| 782 | # shiva.cs cs.berkeley.edu shiva.cs.berkeley.edu |
|---|
| 783 | # shiva cs.berkeley.edu shiva.cs.berekley.edu |
|---|
| 784 | # cumulus reed.edu @reed.edu:cumulus.uucp |
|---|
| 785 | # tiberius tc.cornell.edu tiberius.tc.cornell.edu |
|---|
| 786 | # |
|---|
| 787 | # The first try must always be to cut the domain part out of |
|---|
| 788 | # the server and tack it onto the host. |
|---|
| 789 | # |
|---|
| 790 | # A reasonable second try is to tack the whole server part onto |
|---|
| 791 | # the host and for each possible repeated element, eliminate |
|---|
| 792 | # just that part. |
|---|
| 793 | # |
|---|
| 794 | # These extra "guesses" get put into the %domainify_fallback |
|---|
| 795 | # array. They will be used to give addresses a second chance |
|---|
| 796 | # in the &giveup routine |
|---|
| 797 | # |
|---|
| 798 | |
|---|
| 799 | local(%fallback); |
|---|
| 800 | |
|---|
| 801 | local($long); |
|---|
| 802 | $long = "$host $domain_host"; |
|---|
| 803 | $long =~ tr/A-Z/a-z/; |
|---|
| 804 | print "long = $long\n" if $debug; |
|---|
| 805 | if ($long =~ s/^([^ ]+\.)([^ ]+) \2(\.[^ ]+\.[^ ]+)/$1$2$3/) { |
|---|
| 806 | # matches shiva.cs cs.berkeley.edu and returns shiva.cs.berkeley.edu |
|---|
| 807 | print "condensed fallback $host $domain_host -> $long\n" if $debug; |
|---|
| 808 | $fallback{$long} = 9; |
|---|
| 809 | } |
|---|
| 810 | |
|---|
| 811 | local($fh); |
|---|
| 812 | $fh = $domain_host; |
|---|
| 813 | while ($fh =~ /\./) { |
|---|
| 814 | print "FALLBACK $host.$fh = 1\n" if $debug > 7; |
|---|
| 815 | $fallback{"$host.$fh"} = 1; |
|---|
| 816 | $fh =~ s/^[^\.]+\.//; |
|---|
| 817 | } |
|---|
| 818 | |
|---|
| 819 | $fallback{"$host.$domain_host"} = 2; |
|---|
| 820 | |
|---|
| 821 | ($domain = $domain_host) =~ s/^[^\.]+//; |
|---|
| 822 | $fallback{"$host$domain"} = 6 |
|---|
| 823 | if ($domain =~ /\./); |
|---|
| 824 | |
|---|
| 825 | if ($host =~ /\./) { |
|---|
| 826 | # |
|---|
| 827 | # Host is already okay, but let's look for multiple |
|---|
| 828 | # interpretations |
|---|
| 829 | # |
|---|
| 830 | print "domainify($host,$domain_host) = $host\n" if $debug; |
|---|
| 831 | delete $fallback{$host}; |
|---|
| 832 | $domainify_fallback{"$u *** $host"} = join(' ',sort {$fallback{$b} <=> $fallback{$a};} keys %fallback) if %fallback; |
|---|
| 833 | return $host; |
|---|
| 834 | } |
|---|
| 835 | |
|---|
| 836 | $domain = ".$domain_host" |
|---|
| 837 | if ($domain !~ /\..*\./); |
|---|
| 838 | $newhost = "$host$domain"; |
|---|
| 839 | |
|---|
| 840 | $create_host_backtrack{"$u *** $newhost"} = $domain_host; |
|---|
| 841 | print "domainify($host,$domain_host) = $newhost\n" if $debug; |
|---|
| 842 | delete $fallback{$newhost}; |
|---|
| 843 | $domainify_fallback{"$u *** $newhost"} = join(' ',sort {$fallback{$b} <=> $fallback{$a};} keys %fallback) if %fallback; |
|---|
| 844 | if ($debug) { |
|---|
| 845 | print "fallback = "; |
|---|
| 846 | print $domainify_fallback{"$u *** $newhost"} |
|---|
| 847 | if defined($domainify_fallback{"$u *** $newhost"}); |
|---|
| 848 | print "\n"; |
|---|
| 849 | } |
|---|
| 850 | return $newhost; |
|---|
| 851 | } |
|---|
| 852 | # return the first non-empty element of an array |
|---|
| 853 | sub firstname |
|---|
| 854 | { |
|---|
| 855 | local(@names) = @_; |
|---|
| 856 | local($n); |
|---|
| 857 | while(@names) { |
|---|
| 858 | $n = shift(@names); |
|---|
| 859 | return $n if $n =~ /\S/; |
|---|
| 860 | } |
|---|
| 861 | return undef; |
|---|
| 862 | } |
|---|
| 863 | # queue up more addresses to expand |
|---|
| 864 | sub expn |
|---|
| 865 | { |
|---|
| 866 | local($host,$addr,$name,$level) = @_; |
|---|
| 867 | if ($host) { |
|---|
| 868 | $host = &trhost($host); |
|---|
| 869 | |
|---|
| 870 | if (($debug > 3) || (defined $giveup{$host})) { |
|---|
| 871 | unshift(@hosts,$host) unless $users{$host}; |
|---|
| 872 | } else { |
|---|
| 873 | push(@hosts,$host) unless $users{$host}; |
|---|
| 874 | } |
|---|
| 875 | $users{$host} .= " $addr"; |
|---|
| 876 | $names{"$addr *** $host"} = $name; |
|---|
| 877 | $level{"$addr *** $host"} = $level + 1; |
|---|
| 878 | print "expn($host,$addr,$name)\n" if $debug; |
|---|
| 879 | return "\t$addr\n"; |
|---|
| 880 | } else { |
|---|
| 881 | return &final($addr,'NONE',$name); |
|---|
| 882 | } |
|---|
| 883 | } |
|---|
| 884 | # compute the numerical average value of an array |
|---|
| 885 | sub average |
|---|
| 886 | { |
|---|
| 887 | local(@e) = @_; |
|---|
| 888 | return 0 unless @e; |
|---|
| 889 | local($e,$sum); |
|---|
| 890 | for $e (@e) { |
|---|
| 891 | $sum += $e; |
|---|
| 892 | } |
|---|
| 893 | $sum / @e; |
|---|
| 894 | } |
|---|
| 895 | # print to the server (also to stdout, if -w) |
|---|
| 896 | sub ps |
|---|
| 897 | { |
|---|
| 898 | local($p) = @_; |
|---|
| 899 | print ">>> $p\n" if $watch; |
|---|
| 900 | print $S "$p\n"; |
|---|
| 901 | } |
|---|
| 902 | # return case-adjusted name for a host (for comparison purposes) |
|---|
| 903 | sub trhost |
|---|
| 904 | { |
|---|
| 905 | # treat foo.bar as an alias for Foo.BAR |
|---|
| 906 | local($host) = @_; |
|---|
| 907 | local($trhost) = $host; |
|---|
| 908 | $trhost =~ tr/A-Z/a-z/; |
|---|
| 909 | if ($trhost{$trhost}) { |
|---|
| 910 | $host = $trhost{$trhost}; |
|---|
| 911 | } else { |
|---|
| 912 | $trhost{$trhost} = $host; |
|---|
| 913 | } |
|---|
| 914 | $trhost{$trhost}; |
|---|
| 915 | } |
|---|
| 916 | # re-queue users if an mx record dictates a redirect |
|---|
| 917 | # don't allow a user to be redirected more than once |
|---|
| 918 | sub mxredirect |
|---|
| 919 | { |
|---|
| 920 | local($server,*users) = @_; |
|---|
| 921 | local($u,$nserver,@still_there); |
|---|
| 922 | |
|---|
| 923 | $nserver = &mx($server); |
|---|
| 924 | |
|---|
| 925 | if (&trhost($nserver) ne &trhost($server)) { |
|---|
| 926 | $0 = "$av0 - mx redirect $server -> $nserver\n"; |
|---|
| 927 | for $u (@users) { |
|---|
| 928 | if (defined $mxbacktrace{"$u *** $nserver"}) { |
|---|
| 929 | push(@still_there,$u); |
|---|
| 930 | } else { |
|---|
| 931 | $mxbacktrace{"$u *** $nserver"} = $server; |
|---|
| 932 | print "mxbacktrace{$u *** $nserver} = $server\n" |
|---|
| 933 | if ($debug > 1); |
|---|
| 934 | &expn($nserver,$u,$names{"$u *** $server"}); |
|---|
| 935 | } |
|---|
| 936 | } |
|---|
| 937 | @users = @still_there; |
|---|
| 938 | if (! @users) { |
|---|
| 939 | return $nserver; |
|---|
| 940 | } else { |
|---|
| 941 | return undef; |
|---|
| 942 | } |
|---|
| 943 | } |
|---|
| 944 | return undef; |
|---|
| 945 | } |
|---|
| 946 | # follow mx records, return a hostname |
|---|
| 947 | # also follow temporary redirections comming from &domainify and |
|---|
| 948 | # &mxlookup |
|---|
| 949 | sub mx |
|---|
| 950 | { |
|---|
| 951 | local($h,$u) = @_; |
|---|
| 952 | |
|---|
| 953 | for (;;) { |
|---|
| 954 | if (defined $mx{&trhost($h)} && $h ne $mx{&trhost($h)}) { |
|---|
| 955 | $0 = "$av0 - mx expand $h"; |
|---|
| 956 | $h = $mx{&trhost($h)}; |
|---|
| 957 | return $h; |
|---|
| 958 | } |
|---|
| 959 | if ($u) { |
|---|
| 960 | if (defined $temporary_redirect{"$u *** $h"}) { |
|---|
| 961 | $0 = "$av0 - internal redirect $h"; |
|---|
| 962 | print "Temporary redirect taken $u *** $h -> " if $debug; |
|---|
| 963 | $h = $temporary_redirect{"$u *** $h"}; |
|---|
| 964 | print "$h\n" if $debug; |
|---|
| 965 | next; |
|---|
| 966 | } |
|---|
| 967 | $htr = &trhost($h); |
|---|
| 968 | if (defined $temporary_redirect{"$u *** $htr"}) { |
|---|
| 969 | $0 = "$av0 - internal redirect $h"; |
|---|
| 970 | print "temporary redirect taken $u *** $h -> " if $debug; |
|---|
| 971 | $h = $temporary_redirect{"$u *** $htr"}; |
|---|
| 972 | print "$h\n" if $debug; |
|---|
| 973 | next; |
|---|
| 974 | } |
|---|
| 975 | } |
|---|
| 976 | return $h; |
|---|
| 977 | } |
|---|
| 978 | } |
|---|
| 979 | # look up mx records with the name server. |
|---|
| 980 | # re-queue expansion requests if possible |
|---|
| 981 | # optionally give up on this host. |
|---|
| 982 | sub mxlookup |
|---|
| 983 | { |
|---|
| 984 | local($lastchance,$server,$giveup,*users) = @_; |
|---|
| 985 | local(*T); |
|---|
| 986 | local(*NSLOOKUP); |
|---|
| 987 | local($nh, $pref,$cpref); |
|---|
| 988 | local($o0) = $0; |
|---|
| 989 | local($nserver); |
|---|
| 990 | local($name,$aliases,$type,$len,$thataddr); |
|---|
| 991 | local(%fallback); |
|---|
| 992 | |
|---|
| 993 | return 1 if &mxredirect($server,*users); |
|---|
| 994 | |
|---|
| 995 | if ((defined $mx{$server}) || (! $have_nslookup)) { |
|---|
| 996 | return 0 unless $lastchance; |
|---|
| 997 | &giveup('mx domainify',$giveup); |
|---|
| 998 | return 0; |
|---|
| 999 | } |
|---|
| 1000 | |
|---|
| 1001 | $0 = "$av0 - nslookup of $server"; |
|---|
| 1002 | open(T,">/tmp/expn$$") || die "open > /tmp/expn$$: $!\n"; |
|---|
| 1003 | print T "set querytype=MX\n"; |
|---|
| 1004 | print T "$server\n"; |
|---|
| 1005 | close(T); |
|---|
| 1006 | $cpref = 1.0E12; |
|---|
| 1007 | undef $nserver; |
|---|
| 1008 | open(NSLOOKUP,"nslookup < /tmp/expn$$ 2>&1 |") || die "open nslookup: $!"; |
|---|
| 1009 | while(<NSLOOKUP>) { |
|---|
| 1010 | print if ($debug > 2); |
|---|
| 1011 | if (/mail exchanger = ([-A-Za-z_.0-9+]+)/) { |
|---|
| 1012 | $nh = $1; |
|---|
| 1013 | if (/preference = (\d+)/) { |
|---|
| 1014 | $pref = $1; |
|---|
| 1015 | if ($pref < $cpref) { |
|---|
| 1016 | $nserver = $nh; |
|---|
| 1017 | $cpref = $pref; |
|---|
| 1018 | } elsif ($pref) { |
|---|
| 1019 | $fallback{$pref} .= " $nh"; |
|---|
| 1020 | } |
|---|
| 1021 | } |
|---|
| 1022 | } |
|---|
| 1023 | if (/Non-existent domain/) { |
|---|
| 1024 | # |
|---|
| 1025 | # These addresss are hosed. Kaput! Dead! |
|---|
| 1026 | # However, if we created the address in the |
|---|
| 1027 | # first place then there is a chance of |
|---|
| 1028 | # salvation. |
|---|
| 1029 | # |
|---|
| 1030 | 1 while(<NSLOOKUP>); |
|---|
| 1031 | close(NSLOOKUP); |
|---|
| 1032 | return 0 unless $lastchance; |
|---|
| 1033 | &giveup('domainify',"$server: Non-existent domain",undef,1); |
|---|
| 1034 | return 0; |
|---|
| 1035 | } |
|---|
| 1036 | |
|---|
| 1037 | } |
|---|
| 1038 | close(NSLOOKUP); |
|---|
| 1039 | unlink("/tmp/expn$$"); |
|---|
| 1040 | unless ($nserver) { |
|---|
| 1041 | $0 = "$o0 - finished mxlookup"; |
|---|
| 1042 | return 0 unless $lastchance; |
|---|
| 1043 | &giveup('mx domainify',"$server: Could not resolve address"); |
|---|
| 1044 | return 0; |
|---|
| 1045 | } |
|---|
| 1046 | |
|---|
| 1047 | # provide fallbacks in case $nserver doesn't work out |
|---|
| 1048 | if (defined $fallback{$cpref}) { |
|---|
| 1049 | $mx_secondary{$server} = $fallback{$cpref}; |
|---|
| 1050 | } |
|---|
| 1051 | |
|---|
| 1052 | $0 = "$av0 - gethostbyname($nserver)"; |
|---|
| 1053 | ($name,$aliases,$type,$len,$thataddr) = gethostbyname($nserver); |
|---|
| 1054 | |
|---|
| 1055 | unless ($thataddr) { |
|---|
| 1056 | $0 = $o0; |
|---|
| 1057 | return 0 unless $lastchance; |
|---|
| 1058 | &giveup('mx domainify',"$nserver: could not resolve address"); |
|---|
| 1059 | return 0; |
|---|
| 1060 | } |
|---|
| 1061 | print "MX($server) = $nserver\n" if $debug; |
|---|
| 1062 | print "$server -> $nserver\n" if $vw && !$debug; |
|---|
| 1063 | $mx{&trhost($server)} = $nserver; |
|---|
| 1064 | # redeploy the users |
|---|
| 1065 | unless (&mxredirect($server,*users)) { |
|---|
| 1066 | return 0 unless $lastchance; |
|---|
| 1067 | &giveup('mx domainify',"$nserver: only one level of mx redirect allowed"); |
|---|
| 1068 | return 0; |
|---|
| 1069 | } |
|---|
| 1070 | $0 = "$o0 - finished mxlookup"; |
|---|
| 1071 | return 1; |
|---|
| 1072 | } |
|---|
| 1073 | # if mx expansion did not help to resolve an address |
|---|
| 1074 | # (ie: foo@bar became @baz:foo@bar, then undo the |
|---|
| 1075 | # expansion). |
|---|
| 1076 | # this is only used by &final |
|---|
| 1077 | sub mxunroll |
|---|
| 1078 | { |
|---|
| 1079 | local(*host,*addr) = @_; |
|---|
| 1080 | local($r) = 0; |
|---|
| 1081 | print "looking for mxbacktrace{$addr *** $host}\n" |
|---|
| 1082 | if ($debug > 1); |
|---|
| 1083 | while (defined $mxbacktrace{"$addr *** $host"}) { |
|---|
| 1084 | print "Unrolling MX expnasion: \@$host:$addr -> " |
|---|
| 1085 | if ($debug || $verbose); |
|---|
| 1086 | $host = $mxbacktrace{"$addr *** $host"}; |
|---|
| 1087 | print "\@$host:$addr\n" |
|---|
| 1088 | if ($debug || $verbose); |
|---|
| 1089 | $r = 1; |
|---|
| 1090 | } |
|---|
| 1091 | return 1 if $r; |
|---|
| 1092 | $addr = "\@$host:$addr" |
|---|
| 1093 | if ($host =~ /\./); |
|---|
| 1094 | return 0; |
|---|
| 1095 | } |
|---|
| 1096 | # register a completed expnasion. Make the final address as |
|---|
| 1097 | # simple as possible. |
|---|
| 1098 | sub final |
|---|
| 1099 | { |
|---|
| 1100 | local($addr,$host,$name,$error) = @_; |
|---|
| 1101 | local($he); |
|---|
| 1102 | local($hb,$hr); |
|---|
| 1103 | local($au,$ah); |
|---|
| 1104 | |
|---|
| 1105 | if ($error =~ /Non-existent domain/) { |
|---|
| 1106 | # |
|---|
| 1107 | # If we created the domain, then let's undo the |
|---|
| 1108 | # damage... |
|---|
| 1109 | # |
|---|
| 1110 | if (defined $create_host_backtrack{"$addr *** $host"}) { |
|---|
| 1111 | while (defined $create_host_backtrack{"$addr *** $host"}) { |
|---|
| 1112 | print "Un&domainifying($host) = " if $debug; |
|---|
| 1113 | $host = $create_host_backtrack{"$addr *** $host"}; |
|---|
| 1114 | print "$host\n" if $debug; |
|---|
| 1115 | } |
|---|
| 1116 | $error = "$host: could not locate"; |
|---|
| 1117 | } else { |
|---|
| 1118 | # |
|---|
| 1119 | # If we only want valid addresses, toss out |
|---|
| 1120 | # bad host names. |
|---|
| 1121 | # |
|---|
| 1122 | if ($valid) { |
|---|
| 1123 | print STDERR "\@$host:$addr ($name) Non-existent domain\n"; |
|---|
| 1124 | return ""; |
|---|
| 1125 | } |
|---|
| 1126 | } |
|---|
| 1127 | } |
|---|
| 1128 | |
|---|
| 1129 | MXUNWIND: { |
|---|
| 1130 | $0 = "$av0 - final parsing of \@$host:$addr"; |
|---|
| 1131 | ($he = $host) =~ s/(\W)/\\$1/g; |
|---|
| 1132 | if ($addr !~ /@/) { |
|---|
| 1133 | # addr does not contain any host |
|---|
| 1134 | $addr = "$addr@$host"; |
|---|
| 1135 | } elsif ($addr !~ /$he/i) { |
|---|
| 1136 | # if host part really something else, use the something |
|---|
| 1137 | # else. |
|---|
| 1138 | if ($addr =~ m/(.*)\@([^\@]+)$/) { |
|---|
| 1139 | ($au,$ah) = ($1,$2); |
|---|
| 1140 | print "au = $au ah = $ah\n" if $debug; |
|---|
| 1141 | if (defined $temporary_redirect{"$addr *** $ah"}) { |
|---|
| 1142 | $addr = "$au\@".$temporary_redirect{"$addr *** $ah"}; |
|---|
| 1143 | print "Rewrite! to $addr\n" if $debug; |
|---|
| 1144 | next MXUNWIND; |
|---|
| 1145 | } |
|---|
| 1146 | } |
|---|
| 1147 | # addr does not contain full host |
|---|
| 1148 | if ($valid) { |
|---|
| 1149 | if ($host =~ /^([^\.]+)(\..+)$/) { |
|---|
| 1150 | # host part has a . in it - foo.bar |
|---|
| 1151 | ($hb, $hr) = ($1, $2); |
|---|
| 1152 | if ($addr =~ /\@([^\.\@]+)$/ && ($1 eq $hb)) { |
|---|
| 1153 | # addr part has not . |
|---|
| 1154 | # and matches beginning of |
|---|
| 1155 | # host part -- tack on a |
|---|
| 1156 | # domain name. |
|---|
| 1157 | $addr .= $hr; |
|---|
| 1158 | } else { |
|---|
| 1159 | &mxunroll(*host,*addr) |
|---|
| 1160 | && redo MXUNWIND; |
|---|
| 1161 | } |
|---|
| 1162 | } else { |
|---|
| 1163 | &mxunroll(*host,*addr) |
|---|
| 1164 | && redo MXUNWIND; |
|---|
| 1165 | } |
|---|
| 1166 | } else { |
|---|
| 1167 | $addr = "${addr}[\@$host]" |
|---|
| 1168 | if ($host =~ /\./); |
|---|
| 1169 | } |
|---|
| 1170 | } |
|---|
| 1171 | } |
|---|
| 1172 | $name = "$name " if $name; |
|---|
| 1173 | $error = " $error" if $error; |
|---|
| 1174 | if ($valid) { |
|---|
| 1175 | push(@final,"$name<$addr>"); |
|---|
| 1176 | } else { |
|---|
| 1177 | push(@final,"$name<$addr>$error"); |
|---|
| 1178 | } |
|---|
| 1179 | "\t$name<$addr>$error\n"; |
|---|
| 1180 | } |
|---|
| 1181 | |
|---|
| 1182 | sub alarm |
|---|
| 1183 | { |
|---|
| 1184 | local($alarm_action,$alarm_redirect,$alarm_user) = @_; |
|---|
| 1185 | alarm(3600); |
|---|
| 1186 | $SIG{ALRM} = 'handle_alarm'; |
|---|
| 1187 | } |
|---|
| 1188 | # this involves one great big ugly hack. |
|---|
| 1189 | # the "next HOST" unwinds the stack! |
|---|
| 1190 | sub handle_alarm |
|---|
| 1191 | { |
|---|
| 1192 | &giveup($alarm_redirect,"Timed out during $alarm_action",$alarm_user); |
|---|
| 1193 | next HOST; |
|---|
| 1194 | } |
|---|
| 1195 | |
|---|
| 1196 | # read the rest of the current smtp daemon's response (and toss it away) |
|---|
| 1197 | sub read_response |
|---|
| 1198 | { |
|---|
| 1199 | local($done,$watch) = @_; |
|---|
| 1200 | local(@resp); |
|---|
| 1201 | print $s if $watch; |
|---|
| 1202 | while(($done eq "-") && ($s = <$S>) && ($s =~ /^\d+([- ])/)) { |
|---|
| 1203 | print $s if $watch; |
|---|
| 1204 | $done = $1; |
|---|
| 1205 | push(@resp,$s); |
|---|
| 1206 | } |
|---|
| 1207 | return @resp; |
|---|
| 1208 | } |
|---|
| 1209 | # print args if verbose. Return them in any case |
|---|
| 1210 | sub verbose |
|---|
| 1211 | { |
|---|
| 1212 | local(@tp) = @_; |
|---|
| 1213 | print "@tp" if $verbose; |
|---|
| 1214 | } |
|---|
| 1215 | # to pass perl -w: |
|---|
| 1216 | @tp; |
|---|
| 1217 | $flag_a; |
|---|
| 1218 | $flag_d; |
|---|
| 1219 | $flag_1; |
|---|
| 1220 | %already_domainify_fellback; |
|---|
| 1221 | %already_mx_fellback; |
|---|
| 1222 | &handle_alarm; |
|---|
| 1223 | ################### BEGIN PERL/TROFF TRANSITION |
|---|
| 1224 | .00 ; |
|---|
| 1225 | |
|---|
| 1226 | 'di |
|---|
| 1227 | .nr nl 0-1 |
|---|
| 1228 | .nr % 0 |
|---|
| 1229 | .\\"'; __END__ |
|---|
| 1230 | .\" ############## END PERL/TROFF TRANSITION |
|---|
| 1231 | .TH EXPN 1 "March 11, 1993" |
|---|
| 1232 | .AT 3 |
|---|
| 1233 | .SH NAME |
|---|
| 1234 | expn \- recursively expand mail aliases |
|---|
| 1235 | .SH SYNOPSIS |
|---|
| 1236 | .B expn |
|---|
| 1237 | .RI [ -a ] |
|---|
| 1238 | .RI [ -v ] |
|---|
| 1239 | .RI [ -w ] |
|---|
| 1240 | .RI [ -d ] |
|---|
| 1241 | .RI [ -1 ] |
|---|
| 1242 | .IR user [@ hostname ] |
|---|
| 1243 | .RI [ user [@ hostname ]]... |
|---|
| 1244 | .SH DESCRIPTION |
|---|
| 1245 | .B expn |
|---|
| 1246 | will use the SMTP |
|---|
| 1247 | .B expn |
|---|
| 1248 | and |
|---|
| 1249 | .B vrfy |
|---|
| 1250 | commands to expand mail aliases. |
|---|
| 1251 | It will first look up the addresses you provide on the command line. |
|---|
| 1252 | If those expand into addresses on other systems, it will |
|---|
| 1253 | connect to the other systems and expand again. It will keep |
|---|
| 1254 | doing this until no further expansion is possible. |
|---|
| 1255 | .SH OPTIONS |
|---|
| 1256 | The default output of |
|---|
| 1257 | .B expn |
|---|
| 1258 | can contain many lines which are not valid |
|---|
| 1259 | email addresses. With the |
|---|
| 1260 | .I -aa |
|---|
| 1261 | flag, only expansions that result in legal addresses |
|---|
| 1262 | are used. Since many mailing lists have an illegal |
|---|
| 1263 | address or two, the single |
|---|
| 1264 | .IR -a , |
|---|
| 1265 | address, flag specifies that a few illegal addresses can |
|---|
| 1266 | be mixed into the results. More |
|---|
| 1267 | .I -a |
|---|
| 1268 | flags vary the ratio. Read the source to track down |
|---|
| 1269 | the formula. With the |
|---|
| 1270 | .I -a |
|---|
| 1271 | option, you should be able to construct a new mailing |
|---|
| 1272 | list out of an existing one. |
|---|
| 1273 | .LP |
|---|
| 1274 | If you wish to limit the number of levels deep that |
|---|
| 1275 | .B expn |
|---|
| 1276 | will recurse as it traces addresses, use the |
|---|
| 1277 | .I -1 |
|---|
| 1278 | option. For each |
|---|
| 1279 | .I -1 |
|---|
| 1280 | another level will be traversed. So, |
|---|
| 1281 | .I -111 |
|---|
| 1282 | will traverse no more than three levels deep. |
|---|
| 1283 | .LP |
|---|
| 1284 | The normal mode of operation for |
|---|
| 1285 | .B expn |
|---|
| 1286 | is to do all of its work silently. |
|---|
| 1287 | The following options make it more verbose. |
|---|
| 1288 | It is not necessary to make it verbose to see what it is |
|---|
| 1289 | doing because as it works, it changes its |
|---|
| 1290 | .BR argv [0] |
|---|
| 1291 | variable to reflect its current activity. |
|---|
| 1292 | To see how it is expanding things, the |
|---|
| 1293 | .IR -v , |
|---|
| 1294 | verbose, flag will cause |
|---|
| 1295 | .B expn |
|---|
| 1296 | to show each address before |
|---|
| 1297 | and after translation as it works. |
|---|
| 1298 | The |
|---|
| 1299 | .IR -w , |
|---|
| 1300 | watch, flag will cause |
|---|
| 1301 | .B expn |
|---|
| 1302 | to show you its conversations with the mail daemons. |
|---|
| 1303 | Finally, the |
|---|
| 1304 | .IR -d , |
|---|
| 1305 | debug, flag will expose many of the inner workings so that |
|---|
| 1306 | it is possible to eliminate bugs. |
|---|
| 1307 | .SH ENVIRONMENT |
|---|
| 1308 | No environment variables are used. |
|---|
| 1309 | .SH FILES |
|---|
| 1310 | .PD 0 |
|---|
| 1311 | .B /tmp/expn$$ |
|---|
| 1312 | .B temporary file used as input to |
|---|
| 1313 | .BR nslookup . |
|---|
| 1314 | .SH SEE ALSO |
|---|
| 1315 | .BR aliases (5), |
|---|
| 1316 | .BR sendmail (8), |
|---|
| 1317 | .BR nslookup (8), |
|---|
| 1318 | RFC 823, and RFC 1123. |
|---|
| 1319 | .SH BUGS |
|---|
| 1320 | Not all mail daemons will implement |
|---|
| 1321 | .B expn |
|---|
| 1322 | or |
|---|
| 1323 | .BR vrfy . |
|---|
| 1324 | It is not possible to verify addresses that are served |
|---|
| 1325 | by such daemons. |
|---|
| 1326 | .LP |
|---|
| 1327 | When attempting to connect to a system to verify an address, |
|---|
| 1328 | .B expn |
|---|
| 1329 | only tries one IP address. Most mail daemons |
|---|
| 1330 | will try harder. |
|---|
| 1331 | .LP |
|---|
| 1332 | It is assumed that you are running domain names and that |
|---|
| 1333 | the |
|---|
| 1334 | .BR nslookup (8) |
|---|
| 1335 | program is available. If not, |
|---|
| 1336 | .B expn |
|---|
| 1337 | will not be able to verify many addresses. It will also pause |
|---|
| 1338 | for a long time unless you change the code where it says |
|---|
| 1339 | .I $have_nslookup = 1 |
|---|
| 1340 | to read |
|---|
| 1341 | .I $have_nslookup = |
|---|
| 1342 | .IR 0 . |
|---|
| 1343 | .LP |
|---|
| 1344 | Lastly, |
|---|
| 1345 | .B expn |
|---|
| 1346 | does not handle every valid address. If you have an example, |
|---|
| 1347 | please submit a bug report. |
|---|
| 1348 | .SH CREDITS |
|---|
| 1349 | In 1986 or so, Jon Broome wrote a program of the same name |
|---|
| 1350 | that did about the same thing. It has since suffered bit rot |
|---|
| 1351 | and Jon Broome has dropped off the face of the earth! |
|---|
| 1352 | (Jon, if you are out there, drop me a line) |
|---|
| 1353 | .SH AVAILABILITY |
|---|
| 1354 | The latest version of |
|---|
| 1355 | .B expn |
|---|
| 1356 | is available through anonymous ftp at |
|---|
| 1357 | .IR ftp://ftp.idiom.com/pub/muir-programs/expn . |
|---|
| 1358 | .SH AUTHOR |
|---|
| 1359 | .I David Muir Sharnoff\ \ \ \ <muir@idiom.com> |
|---|
