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Log DMARC DNS lookup failures instead of silently skipping protection #2074

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Log DMARC DNS lookup failures instead of silently skipping protection #2074

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14 changes: 12 additions & 2 deletions src/lib/Sympa/Message.pm
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Original file line number Diff line number Diff line change
Expand Up @@ -3487,8 +3487,18 @@ sub _check_dmarc_rr {
my $rrstr;
my $sp = 0;
while (0 <= index $domain, '.') {
my $packet = $dns->query("_dmarc.$domain", 'TXT');
next unless $packet;
# Note: send() is used instead of query(), because the latter returns
# undef both when the lookup failed and when it succeeded without any
# matching record. send() returns undef only in the former case, so
# that a failure (blocked socket, timeout, SERVFAIL etc.) can be
# reported instead of being taken for "domain has no DMARC record".
my $packet = $dns->send("_dmarc.$domain", 'TXT');
unless ($packet) {
$log->syslog('err',
'DNS lookup of "_dmarc.%s" TXT failed: %s. DMARC protection is not applied',
$domain, $dns->errorstring);
next;
}

($rrstr) = grep { $_ and $_ =~ /\Av=DMARC/i } map {
# Note: txtdata() of Net::DNS::RR::TXT >=0.69 returns array of
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