fix rendering of ipv(4|6) literal lmtp transports

While reviewing support for lmtp as transport one thing I forgot to
test was adding a lmtp-transport pointing to an IPv6 address.

Using the use_mx flag (which only makes sense for domain-names) to
provide the information of whether the next-hop/hostname should be
written out in square brackets or not is a bit confusing, and leads
to ambiguous results when providing ipv6 literal addresses:
> host: 2001:db8:25::25
> port: 24
> gets rendered as
> lmtp:inet:2001:db8:25::25:24

Which postfix oddly enough parses 'correctly'; postfix splits on ':'
and uses the last part as port. For ip4 literals and dns-names this
works for ip6 literals it only works if you provide a port so it
makes more sense to always write ip(4|6) literals in brackets

By introducing a explicit flag "$bracket_host" and reordering the
conditions lmtp and smtp entries get rendered correctly (see `man
smtp`).

Additionally fixes an indentation glitch in read_transport_map.

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
Reviewed-By: Dominik Csapak <d.csapak@proxmox.com>

diff --git a/src/PMG/Config.pm b/src/PMG/Config.pm
index 5b5f03fae076dbb4c3925927f8e71a21952662b5..3c839448e1fb0dab86db2f11d13c182cd15d84af 100755 (executable)
--- a/src/PMG/Config.pm
+++ b/src/PMG/Config.pm
@@ -1138,7 +1138,7 @@ sub read_transport_map {
                $host = $1;
                $use_mx = 0;
            }
-               $use_mx = 0 if ($protocol eq "lmtp");
+           $use_mx = 0 if ($protocol eq "lmtp");
 
            eval { PVE::JSONSchema::pve_verify_address($host); };
            if (my $err = $@) {
@@ -1177,19 +1177,21 @@ sub write_transport_map {
            if defined($comment) && $comment !~ m/^\s*$/;
 
        my $use_mx = $data->{use_mx};
-       $use_mx = 0 if $data->{host} =~ m/^(?:$IPV4RE|$IPV6RE)$/;
+       my $bracket_host = ! $use_mx;
 
        if ($data->{protocol} eq 'lmtp') {
-           $use_mx = 1;
+           $bracket_host = 0;
            $data->{protocol} .= ":inet";
        }
 
-       if ($use_mx) {
+       $bracket_host = 1 if $data->{host} =~ m/^(?:$IPV4RE|$IPV6RE)$/i;
+
+       if ($bracket_host) {
            PVE::Tools::safe_print(
-               $filename, $fh, "$data->{domain} $data->{protocol}:$data->{host}:$data->{port}\n");
+               $filename, $fh, "$data->{domain} $data->{protocol}:[$data->{host}]:$data->{port}\n");
        } else {
            PVE::Tools::safe_print(
-               $filename, $fh, "$data->{domain} $data->{protocol}:[$data->{host}]:$data->{port}\n");
+               $filename, $fh, "$data->{domain} $data->{protocol}:$data->{host}:$data->{port}\n");
        }
     }
 }