FreeBSD master.passwd recovery from spwd.db (perl)

#!/usr/bin/perl

use DB_File;

$X = tie %h, "DB_File", "spwd.db", O_RDWR, 0600, $DB_HASH;

@results = ();
@fields = ( 0, 1, 2, 3, 5, 4, 9, 6, 7, 8 );

while( $X->seq($key, $value, R_NEXT) == 0 ) {
@keyent = unpack("C", $key);
if ($keyent[0] == 0x42) {
@keyent = unpack("CN", $key);
@pwent = unpack("Z*Z*NNNZ*Z*Z*Z*NN", $value);
$result = "";
for ($i = 0; $i < 10; $i++) {
if ($pwent[10] & (1 << $i)) {
$result .= $pwent[$fields[$i]];
}
if ($i < 9) {
$result .= ":";
}
}
$results[$keyent[1]] = $result;
}
}

foreach (@results) {
print $_ . "\n";
}

untie %h;