dnsmasq: allow using dnsmasq as the sole resolver
authorYousong Zhou <yszhou4tech@gmail.com>
Mon, 18 Feb 2019 14:11:19 +0000 (14:11 +0000)
committerYousong Zhou <yszhou4tech@gmail.com>
Sun, 24 Feb 2019 01:55:47 +0000 (01:55 +0000)
Currently it seems impossible to configure /etc/config/dhcp to achieve
the following use case

 - run dnsmasq with no-resolv
 - re-generate /etc/resolv.conf with "nameserver 127.0.0.1"

Before this change, we have to set resolvfile to /tmp/resolv.conf.auto
to achive the 2nd effect above, but setting resolvfile requires noresolv
being false.

A new boolean option "localuse" is added to indicate that we intend to
use dnsmasq as the local dns resolver.  It's false by default and to
align with old behaviour it will be true automatically if resolvfile is
set to /tmp/resolv.conf.auto

(cherry picked from 2aea1ada65f050d74a064e74466bbe4e8d)
Tested-by: Paul Oranje <por@oranjevos.nl>
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
Acked-by: Hans Dedecker <dedeckeh@gmail.com>
Acked-by: Paul Oranje <por@oranjevos.nl>
package/network/services/dnsmasq/Makefile
package/network/services/dnsmasq/files/dnsmasq.init

index e89ad19..c50717d 100644 (file)
@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=dnsmasq
 PKG_VERSION:=2.80
-PKG_RELEASE:=1.2
+PKG_RELEASE:=1.3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=http://thekelleys.org.uk/dnsmasq
index 9c922ee..b119981 100644 (file)
@@ -731,7 +731,9 @@ dhcp_relay_add() {
 
 dnsmasq_start()
 {
-       local cfg="$1" disabled resolvfile user_dhcpscript
+       local cfg="$1"
+       local disabled user_dhcpscript
+       local resolvfile localuse
 
        config_get_bool disabled "$cfg" disabled 0
        [ "$disabled" -gt 0 ] && return 0
@@ -881,14 +883,14 @@ dnsmasq_start()
        config_get_bool cachelocal "$cfg" cachelocal 1
 
        config_get_bool noresolv "$cfg" noresolv 0
+       config_get_bool localuse "$cfg" localuse 0
        if [ "$noresolv" != "1" ]; then
-               config_get resolvfile "$cfg" resolvfile "/tmp/resolv.conf.auto"
-               # So jail doesn't complain if file missing
-               [ -n "$resolvfile" -a \! -e "$resolvfile" ] && touch "$resolvfile"
+               config_get resolvfile "$cfg" resolvfile /tmp/resolv.conf.auto
+               [ -n "$resolvfile" -a ! -e "$resolvfile" ] && touch "$resolvfile"
+               xappend "--resolv-file=$resolvfile"
+               [ "$resolvfile" = "/tmp/resolv.conf.auto" ] && localuse=1
        fi
 
-       [ -n "$resolvfile" ] && xappend "--resolv-file=$resolvfile"
-
        config_get hostsfile "$cfg" dhcphostsfile
        [ -e "$hostsfile" ] && xappend "--dhcp-hostsfile=$hostsfile"
 
@@ -1010,7 +1012,7 @@ dnsmasq_start()
        mv -f $CONFIGFILE_TMP $CONFIGFILE
        mv -f $HOSTFILE_TMP $HOSTFILE
 
-       [ "$resolvfile" = "/tmp/resolv.conf.auto" ] && {
+       [ "$localuse" -gt 0 ] && {
                rm -f /tmp/resolv.conf
                [ $ADD_LOCAL_DOMAIN -eq 1 ] && [ -n "$DOMAIN" ] && {
                        echo "search $DOMAIN" >> /tmp/resolv.conf
@@ -1036,17 +1038,15 @@ dnsmasq_start()
 
 dnsmasq_stop()
 {
-       local cfg="$1" resolvfile
+       local cfg="$1"
+       local noresolv resolvfile localuse
 
+       config_get_bool noresolv "$cfg" noresolv 0
+       config_get_bool localuse "$cfg" localuse 0
        config_get resolvfile "$cfg" "resolvfile"
 
-       #relink /tmp/resolve.conf only for main instance
-       [ "$resolvfile" = "/tmp/resolv.conf.auto" ] && {
-               [ -f /tmp/resolv.conf ] && {
-                       rm -f /tmp/resolv.conf
-                       ln -s "$resolvfile" /tmp/resolv.conf
-               }
-       }
+       [ "$noresolv" = 0 -a "$resolvfile" = "/tmp/resolv.conf.auto" ] && localuse=1
+       [ "$localuse" -gt 0 ] && ln -sf "/tmp/resolv.conf.auto" /tmp/resolv.conf
 
        rm -f ${BASEDHCPSTAMPFILE}.${cfg}.*.dhcp
 }