Resolve CNAMES recursively

This complements b2e15909.

1 files changed, 21 insertions, 3 deletions

diff --git a/acmeman b/acmeman
index e6fee16..37ed4dd 100755
--- a/acmeman
+++ b/acmeman
@@ -1,4 +1,7 @@
-#!/usr/bin/perl
+#!/bin/sh
+#!-*-perl-*-
+eval 'exec /usr/bin/perl  -S $0 ${1+"$@"}'
+    if 0; # not running under some shell
 # Copyright (C) 2017, 2018 Sergey Poznyakoff <gray@gnu.org>
 #
 # This program is free software; you can redistribute it and/or modify
@@ -893,7 +896,7 @@ sub resolve {
     unless ($res) {
         $res = new Net::DNS::Resolver();
     }
-    my $q = $res->query($host, 'A');
+    my $q = $res->query($host,'ANY');
     unless ($q) {
         if ($res->errorstring eq 'NXDOMAIN') {
             debug(1, "$host: no such host");
@@ -905,7 +908,22 @@ sub resolve {
         }
         return ();
     }
-    return map { $_->rdatastr } grep { $_->type eq 'A' } $q->answer;
+    my %res;
+    my %cnames;
+    my @answer = $q->answer();
+    while (my $ans = shift @answer) {
+        if ($ans->type eq 'A') {
+            $res{$ans->rdatastr} = 1;
+        } elsif ($ans->type eq 'CNAME') {
+            unless ($cnames{$ans->owner}) { # Avoid eventual loops
+                $cnames{$ans->owner} = 1;
+                if (my $q = $res->query($ans->cname, 'A')) {
+                    push @answer, ($q->answer());
+                }
+            }
+        }
+    }
+    keys %res;
 }
 
 sub myip {