From 0d146c23175f70ffa0281c5de63cf12c9c7d8352 Mon Sep 17 00:00:00 2001
From: Stan Grishin <stangri@melmac.net>
Date: Thu, 31 Oct 2019 12:55:23 -0700
Subject: [PATCH] https-dns-proxy: implement dnsmasq integration

Signed-off-by: Stan Grishin <stangri@melmac.net>
---
 net/https-dns-proxy/Makefile                  |  6 +-
 .../files/https_dns_proxy.init                | 72 +++++++++++++++++--
 2 files changed, 71 insertions(+), 7 deletions(-)

diff --git a/net/https-dns-proxy/Makefile b/net/https-dns-proxy/Makefile
index 6e9f8e1cdc..c29a32b4f4 100644
--- a/net/https-dns-proxy/Makefile
+++ b/net/https-dns-proxy/Makefile
@@ -2,7 +2,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=https_dns_proxy
 PKG_VERSION:=2018-04-23
-PKG_RELEASE=3
+PKG_RELEASE=4
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_MIRROR_HASH:=24b7e4238c37e646f33eee3a374f6b7beb5c167b9c5008cc13b51e5f1f3a44ea
@@ -16,10 +16,12 @@ PKG_LICENSE:=MIT
 include $(INCLUDE_DIR)/package.mk
 include $(INCLUDE_DIR)/cmake.mk
 
+CMAKE_OPTIONS += -DCLANG_TIDY_EXE=
+
 define Package/https_dns_proxy
   SECTION:=net
   CATEGORY:=Network
-  TITLE:=DNS over HTTPS proxy server
+  TITLE:=DNS over HTTPS Proxy Server
   DEPENDS:=+libcares +libcurl +libev +ca-bundle
 endef
 
diff --git a/net/https-dns-proxy/files/https_dns_proxy.init b/net/https-dns-proxy/files/https_dns_proxy.init
index 645c17aa46..5dee453d20 100644
--- a/net/https-dns-proxy/files/https_dns_proxy.init
+++ b/net/https-dns-proxy/files/https_dns_proxy.init
@@ -1,7 +1,9 @@
 #!/bin/sh /etc/rc.common
+# Copyright 2019 Stan Grishin (stangri@melmac.net)
+# shellcheck disable=SC2039
 
-START=80
-USE_PROCD=1
+export START=80
+export USE_PROCD=1
 
 PROG=/usr/sbin/https_dns_proxy
 
@@ -19,10 +21,10 @@ append_parm() {
 }
 
 start_instance() {
-	local cfg="$1" param
+	local cfg="$1" param listen_addr listen_port
 
 	append_parm "$cfg" 'listen_addr' '-a' '127.0.0.1'
-	append_parm "$cfg" 'listen_port' '-p' '5053'
+	append_parm "$cfg" 'listen_port' '-p' "$p"
 	append_parm "$cfg" 'bootstrap_dns' '-b'
 	append_parm "$cfg" 'url_prefix' '-r'
 	append_parm "$cfg" 'user' '-u' 'nobody'
@@ -31,16 +33,76 @@ start_instance() {
 	append_parm "$cfg" 'proxy_server' '-t'
 
 	procd_open_instance
+# shellcheck disable=SC2086
 	procd_set_param command ${PROG} ${param}
 	procd_set_param respawn
 	procd_close_instance
+
+	config_get listen_addr "$cfg" 'listen_addr' '127.0.0.1'
+	config_get listen_port "$cfg" 'listen_port' "$p"
+	config_load 'dhcp'
+# shellcheck disable=SC2154
+	config_foreach dnsmasq_add_doh_server 'dnsmasq' "${listen_addr}#${listen_port}"
+	p="$((p+1))"
 }
 
 service_triggers() {
-	procd_add_reload_trigger "https_dns_proxy"
+	procd_add_reload_trigger 'https_dns_proxy'
 }
 
 start_service() {
+	local p=5053
+	dhcp_backup 'create'
 	config_load 'https_dns_proxy'
 	config_foreach start_instance 'https_dns_proxy'
+	if [ -z "$(uci -q get dhcp.@dnsmasq[0].server)" ]; then
+		dhcp_backup 'restore'
+	fi
+	if [ -n "$(uci -q changes dhcp)" ]; then
+		uci -q commit dhcp
+		[ -x /etc/init.d/dnsmasq ] && /etc/init.d/dnsmasq restart >/dev/null 2>&1
+	fi
+}
+
+stop_service() {
+	dhcp_backup 'restore'
+	if [ -n "$(uci -q changes dhcp)" ]; then
+		uci -q commit dhcp
+		[ -x /etc/init.d/dnsmasq ] && /etc/init.d/dnsmasq restart >/dev/null 2>&1
+	fi
+}
+
+dnsmasq_add_doh_server() {
+	local cfg="$1" value="$2"
+	uci -q add_list dhcp."$cfg".server="$value"
+}
+
+dnsmasq_create_server_backup() {
+	local cfg="$1" i
+	if ! uci -q get "dhcp.$cfg.doh_backup_server" >/dev/null; then
+		for i in $(uci -q get "dhcp.$cfg.server"); do
+			uci -q add_list dhcp."$cfg".doh_backup_server="$i"
+		done
+	fi
+	uci -q del "dhcp.$cfg.server"
+}
+
+dnsmasq_restore_server_backup() {
+	local cfg="$1" i
+	if uci -q get "dhcp.$cfg.doh_backup_server" >/dev/null; then
+		uci -q del "dhcp.$cfg.server"
+		for i in $(uci -q get "dhcp.$cfg.doh_backup_server"); do
+			uci -q add_list dhcp."$cfg".server="$i"
+		done
+	fi
+}
+
+dhcp_backup() {
+	config_load 'dhcp'
+	case "$1" in
+		create)
+			config_foreach dnsmasq_create_server_backup 'dnsmasq';;
+		restore)
+			config_foreach dnsmasq_restore_server_backup 'dnsmasq';;
+	esac
 }
-- 
2.30.2