From ec1d9b80f5c95f25d56f10b2cbbc1731f53fe195 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20Men=C5=A1=C3=ADk?= <pemensik@redhat.com>
Date: Tue, 25 Sep 2018 18:08:46 +0200
Subject: [PATCH] Disable IDN from environment as documented

Manual page of host contained instructions to disable IDN processing
when it was built with libidn2. When refactoring IDN support however,
support for disabling IDN in host and nslookup was lost. Use also
environment variable and document it for nslookup, host and dig.
---
 bin/dig/dig.docbook      |  4 +++-
 bin/dig/dighost.c        |  4 ++--
 bin/dig/host.docbook     |  2 +-
 bin/dig/nslookup.docbook | 15 +++++++++++++++
 4 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/bin/dig/dig.docbook b/bin/dig/dig.docbook
index 22ba7f2ed1..f177ca713e 100644
--- a/bin/dig/dig.docbook
+++ b/bin/dig/dig.docbook
@@ -1330,7 +1330,9 @@ dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr
       reply from the server.
       If you'd like to turn off the IDN support for some reason, use
       parameters <parameter>+noidnin</parameter> and
-      <parameter>+noidnout</parameter>.
+      <parameter>+noidnout</parameter> or define
+      the <envar>IDN_DISABLE</envar> environment variable.
+
     </para>
   </refsection>
 
diff --git a/bin/dig/dighost.c b/bin/dig/dighost.c
index 2903bb020c..522c5761f4 100644
--- a/bin/dig/dighost.c
+++ b/bin/dig/dighost.c
@@ -628,8 +628,8 @@ make_empty_lookup(void) {
 	looknew->ttlunits = false;
 	looknew->qr = false;
 #ifdef HAVE_LIBIDN2
-	looknew->idnin = true;
-	looknew->idnout = true;
+	looknew->idnin = (getenv("IDN_DISABLE") == NULL);
+	looknew->idnout = looknew->idnin;
 #else
 	looknew->idnin = false;
 	looknew->idnout = false;
diff --git a/bin/dig/host.docbook b/bin/dig/host.docbook
index 36fcf51de4..1db8798d30 100644
--- a/bin/dig/host.docbook
+++ b/bin/dig/host.docbook
@@ -389,7 +389,7 @@
       <command>host</command> appropriately converts character encoding of
       domain name before sending a request to DNS server or displaying a
       reply from the server.
-      If you'd like to turn off the IDN support for some reason, defines
+      If you'd like to turn off the IDN support for some reason, define
       the <envar>IDN_DISABLE</envar> environment variable.
       The IDN support is disabled if the variable is set when
       <command>host</command> runs.
diff --git a/bin/dig/nslookup.docbook b/bin/dig/nslookup.docbook
index 3aff4e984d..86a09c658e 100644
--- a/bin/dig/nslookup.docbook
+++ b/bin/dig/nslookup.docbook
@@ -478,6 +478,21 @@ nslookup -query=hinfo  -timeout=10
     </para>
   </refsection>
 
+  <refsection><info><title>IDN SUPPORT</title></info>
+
+    <para>
+      If <command>nslookup</command> has been built with IDN (internationalized
+      domain name) support, it can accept and display non-ASCII domain names.
+      <command>nslookup</command> appropriately converts character encoding of
+      domain name before sending a request to DNS server or displaying a
+      reply from the server.
+      If you'd like to turn off the IDN support for some reason, define
+      the <envar>IDN_DISABLE</envar> environment variable.
+      The IDN support is disabled if the variable is set when
+      <command>nslookup</command> runs.
+    </para>
+  </refsection>
+
   <refsection><info><title>FILES</title></info>
 
     <para><filename>/etc/resolv.conf</filename>