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From 02912602842a5b2251b1455cf7206cfee3d18553 Mon Sep 17 00:00:00 2001 |
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From: Matt Simerson <matt@tnpi.net> |
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Date: Tue, 11 May 2010 01:41:08 -0400 |
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Subject: rewrote sender_permitted_from |
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|
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rewrote the plugin using Mail::SPF, which is the replacement for Mail::SPF::Query (by the same author). The two plugins are mutually exclusive and SpamAssassin expects to have Mail::SPF available. |
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|
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Signed-off-by: Robert <rspier@pobox.com> |
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--- |
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plugins/sender_permitted_from | 193 ++++++++++++++++++++++------------------ |
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1 files changed, 106 insertions(+), 87 deletions(-) |
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|
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diff --git a/plugins/sender_permitted_from b/plugins/sender_permitted_from |
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index 287847e..a6d833b 100644 |
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--- a/plugins/sender_permitted_from |
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+++ b/plugins/sender_permitted_from |
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@@ -5,119 +5,138 @@ SPF - plugin to implement Sender Permitted From |
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|
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=head1 SYNOPSIS |
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|
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- # in config/plugins |
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- sender_permitted_from |
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+Prevents email sender address spoofing by checking the SPF policy of the purported senders domain. |
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|
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-Or if you wish to issue 5xx on SPF fail: |
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+=head1 DESCRIPTION |
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|
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- sender_permitted_from spf_deny 1 |
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+Sender Policy Framework (SPF) is an e-mail validation system designed to prevent spam by addressing source address spoofing. SPF allows administrators to specify which hosts are allowed to send e-mail from a given domain by creating a specific SPF record in the public DNS. Mail exchangers then use the DNS to check that mail from a given domain is being sent by a host sanctioned by that domain's administrators. -- http://en.wikipedia.org/wiki/Sender_Policy_Framework |
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+ |
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+=head1 CONFIGURATION |
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|
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-Other arguments are 'trust 0' and 'guess 0'. These turn off processing of |
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-spf.trusted-forwarders.org and the best_guess functionality. It is unlikely |
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-that you want to turn these off. |
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+In config/plugins, add arguments to the sender_permitted_from line. |
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|
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-Adding 'spf_deny 2' will also issue a 5xx on a softfail response. |
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+ sender_permitted_from spf_deny 1 |
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|
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-You can also specify local SPF policy with |
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+=head2 spf_deny |
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|
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- include '<spf mechanism list>' |
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+Setting spf_deny to 0 will prevent emails from being rejected, even if they fail SPF checks. sfp_deny 1 is the default, and a reasonable setting. It temporarily defers connections (4xx) that have soft SFP failures and only rejects (5xx) messages when the sending domains policy suggests it. Settings spf_deny to 2 is more aggressive and will cause soft failures to be rejected permanently. |
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|
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See also http://spf.pobox.com/ |
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|
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+=head1 AUTHOR |
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+ |
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+Matt Simerson <msimerson@cpan.org> |
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+ |
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+=head1 ACKNOWLEDGEMENTS |
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+ |
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+whomever wrote the original SPF plugin, upon which I based this. |
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+ |
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=cut |
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|
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-use Mail::SPF::Query 1.991; |
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+use strict; |
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+use Mail::SPF 2.000; |
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+use Data::Dumper; |
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|
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sub register { |
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- my ($self, $qp, @args) = @_; |
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- %{$self->{_args}} = @args; |
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+ my ($self, $qp, @args) = @_; |
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+ %{$self->{_args}} = @args; |
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} |
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|
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sub hook_mail { |
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- my ($self, $transaction, $sender, %param) = @_; |
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- |
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- return (DECLINED) unless ($sender->format ne "<>" |
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- and $sender->host && $sender->user); |
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- |
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- # If we are receving from a relay permitted host, then we are probably |
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- # not the delivery system, and so we shouldn't check |
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- |
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- return (DECLINED) if $self->qp->connection->relay_client(); |
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- my @relay_clients = $self->qp->config("relayclients"); |
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- my $more_relay_clients = $self->qp->config("morerelayclients", "map"); |
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- my %relay_clients = map { $_ => 1 } @relay_clients; |
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- my $client_ip = $self->qp->connection->remote_ip; |
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- while ($client_ip) { |
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- return (DECLINED) if exists $relay_clients{$client_ip}; |
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- return (DECLINED) if exists $more_relay_clients->{$client_ip}; |
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- $client_ip =~ s/\d+\.?$//; # strip off another 8 bits |
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- } |
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- |
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- my $host = lc $sender->host; |
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- my $from = $sender->user . '@' . $host; |
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- |
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- my $ip = $self->qp->connection->remote_ip; |
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- my $helo = $self->qp->connection->hello_host; |
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- |
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- my $query = Mail::SPF::Query->new(ip => $ip, sender => $from, helo => $helo, |
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- sanitize => 1, |
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- local => $self->{_args}{local}, |
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- guess => defined($self->{_args}{guess}) ? $self->{_args}{guess} : 1, |
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- trusted => defined($self->{_args}{trust}) ? $self->{_args}{trust} : 1) |
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- || die "Couldn't construct Mail::SPF::Query object"; |
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- $transaction->notes('spfquery', $query); |
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- |
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- return (DECLINED); |
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+ my ($self, $transaction, $sender, %param) = @_; |
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+ |
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+ my $format = $sender->format; |
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+ my $host = lc $sender->host; |
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+ my $user = $sender->user; |
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+ my $client_ip = $self->qp->connection->remote_ip; |
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+ my $from = $sender->user . '@' . $host; |
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+ my $helo = $self->qp->connection->hello_host; |
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+ |
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+ return (DECLINED, "SPF - null sender") |
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+ unless ($format ne "<>" && $host && $user); |
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+ |
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+ # If we are receving from a relay permitted host, then we are probably |
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+ # not the delivery system, and so we shouldn't check |
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+ return (DECLINED, "SPF - relaying permitted") |
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+ if $self->qp->connection->relay_client(); |
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+ |
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+ my @relay_clients = $self->qp->config("relayclients"); |
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+ my $more_relay_clients = $self->qp->config("morerelayclients", "map"); |
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+ my %relay_clients = map { $_ => 1 } @relay_clients; |
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+ while ($client_ip) { |
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+ return (DECLINED, "SPF - relaying permitted") |
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+ if exists $relay_clients{$client_ip}; |
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+ return (DECLINED, "SPF - relaying permitted") |
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+ if exists $more_relay_clients->{$client_ip}; |
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+ $client_ip =~ s/\d+\.?$//; # strip off another 8 bits |
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+ } |
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+ |
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+ my $scope = $from ? 'mfrom' : 'helo'; |
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+ $client_ip = $self->qp->connection->remote_ip; |
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+ my %req_params = ( |
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+ versions => [1, 2], # optional |
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+ scope => $scope, |
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+ ip_address => $client_ip, |
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+ ); |
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+ |
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+ if ($scope =~ /mfrom|pra/) { |
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+ $req_params{identity} = $from; |
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+ $req_params{helo_identity} = $helo if $helo; |
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+ } |
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+ elsif ($scope eq 'helo') { |
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+ $req_params{identity} = $helo; |
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+ $req_params{helo_identity} = $helo; |
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+ } |
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+ |
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+ my $spf_server = Mail::SPF::Server->new(); |
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+ my $request = Mail::SPF::Request->new(%req_params); |
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+ my $result = $spf_server->process($request); |
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+ |
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+ $transaction->notes('spfquery', $result); |
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+ |
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+ return (OK) if $result->code eq 'pass'; # this test passed |
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+ return (DECLINED, "SPF - $result->code"); |
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} |
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|
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sub hook_rcpt { |
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- my ($self, $transaction, $rcpt, %param) = @_; |
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- |
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- # special addresses don't get SPF-tested. |
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- return DECLINED if $rcpt and $rcpt->user and $rcpt->user =~ /^(?:postmaster|abuse|mailer-daemon|root)$/i; |
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- |
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- my $query = $transaction->notes('spfquery'); |
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- |
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- return DECLINED if !$query; |
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- my ($result, $smtp_comment, $comment) = $query->result2($rcpt->address); |
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- |
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- if ($result eq "error") { |
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- return (DENYSOFT, "SPF error: $smtp_comment"); |
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- } |
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- |
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- if ($result eq "fail" and $self->{_args}{spf_deny}) { |
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- return (DENY, "SPF forgery: $smtp_comment"); |
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- } |
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- |
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- if ($result eq "softfail" and $self->{_args}{spf_deny} > 1) { |
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- return (DENY, "SPF probable forgery: $smtp_comment"); |
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- } |
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- |
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- if ($result eq 'fail' or $result eq 'softfail') { |
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- $self->log(LOGDEBUG, "result for $rcpt->address was $result: $comment"); |
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- } |
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- |
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- return DECLINED; |
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-} |
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+ my ($self, $transaction, $rcpt, %param) = @_; |
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+ |
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+ # special addresses don't get SPF-tested. |
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+ return DECLINED |
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+ if $rcpt |
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+ and $rcpt->user |
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+ and $rcpt->user =~ /^(?:postmaster|abuse|mailer-daemon|root)$/i; |
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+ |
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+ my $result = $transaction->notes('spfquery') or return DECLINED; |
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+ my $code = $result->code; |
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+ my $why = $result->local_explanation; |
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+ my $deny = $self->{_args}{spf_deny}; |
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+ |
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+ return (DECLINED, "SPF - $code: $why") if $code eq "pass"; |
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+ return (DECLINED, "SPF - $code, $why") if !$deny; |
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+ return (DENYSOFT, "SPF - $code: $why") if $code eq "error"; |
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+ return (DENY, "SPF - forgery: $why") if $code eq 'fail'; |
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|
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-sub _uri_escape { |
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- my $str = shift; |
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- $str =~ s/([^A-Za-z0-9\-_.!~*\'()])/sprintf "%%%X", ord($1)/eg; |
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- return $str; |
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+ if ($code eq "softfail") { |
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+ return (DENY, "SPF probable forgery: $why") if $deny > 1; |
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+ return (DENYSOFT, "SPF probable forgery: $why"); |
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+ } |
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+ |
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+ $self->log(LOGDEBUG, "result for $rcpt->address was $code: $why"); |
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+ |
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+ return (DECLINED, "SPF - $code, $why"); |
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} |
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|
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sub hook_data_post { |
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- my ($self, $transaction) = @_; |
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- |
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- my $query = $transaction->notes('spfquery'); |
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- return DECLINED if !$query; |
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+ my ($self, $transaction) = @_; |
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|
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- my ($result, $smtp_comment, $comment) = $query->message_result2(); |
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+ my $result = $transaction->notes('spfquery') or return DECLINED; |
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|
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- $self->log(LOGDEBUG, "result was $result: $comment") if ($result); |
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+ $self->log(LOGDEBUG, "result was $result->code"); |
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|
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- $transaction->header->add('Received-SPF' => "$result ($comment)", 0); |
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+ $transaction->header->add('Received-SPF' => $result->received_spf_header, |
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+ 0); |
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|
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- return DECLINED; |
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+ return DECLINED; |
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} |
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|
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-- |
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1.7.2.2 |
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