From aecfa365a055022a087b2ed57099bba1d3b4cfa1 Mon Sep 17 00:00:00 2001
From: Andrey Golovizin <ag@sologoc.com>
Date: Wed, 14 Jul 2021 14:48:42 +0200
Subject: [PATCH] Add -4/--no-ipv6 option

---
 src/main.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/main.rs b/src/main.rs
index 92c4fc9..b4cc9f1 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -29,6 +29,9 @@ struct ConfigOpts {
 
     #[clap(short, long)]
     no_dns: bool,
+
+    #[clap(short='4', long)]
+    no_ipv6: bool,
 }
 
 #[derive(Clap, Debug)]
@@ -168,8 +171,10 @@ fn write_config(
     writeln!(output, "PrivateKey = {}", &keys.private_key)?;
     writeln!(output, "Address = {}", &config.data.address)?;
     if !config_opts.no_dns {
+        let dns_addrs = config.data.dns()?;
+        let allowed_dns_addrs = dns_addrs.iter().filter(|addr| addr.is_ipv4() || !config_opts.no_ipv6);
         write!(output, "DNS = ")?;
-        write_list(output, config.data.dns()?)?;
+        write_list(output, allowed_dns_addrs)?;
     }
     writeln!(output)?;