dnsmasq: Add match section support

Match sections allow to set a tag specified by the option networkid if the client
sends an option and optionally the option value specified by the match option.
The force option will convert the dhcp-option to force-dhcp-option if set to 1 in
the dnsmasq config if options are specified in the dhcp_option option.

config match
    option networkid tag
    option match 12,myhost
    option force 1
    list dhcp_option '3,192.168.1.1'

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

package/network/services/dnsmasq/files/dnsmasq.init

@@ -351,6 +351,22 @@ dhcp_vendorclass_add() {
 	dhcp_option_add "$cfg" "$networkid" "$force"
 }
 
+dhcp_match_add() {
+	local cfg="$1"
+
+	config_get networkid "$cfg" networkid
+	[ -n "$networkid" ] || return 0
+
+	config_get match "$cfg" match
+	[ -n "$match" ] || return 0
+
+	xappend "--dhcp-match=$networkid,$match"
+
+	config_get_bool force "$cfg" force 0
+
+	dhcp_option_add "$cfg" "$networkid" "$force"
+}
+
 dhcp_host_add() {
 	local cfg="$1"
 
@@ -669,6 +685,7 @@ start_service() {
 	config_foreach dhcp_circuitid_add circuitid
 	config_foreach dhcp_remoteid_add remoteid
 	config_foreach dhcp_subscrid_add subscrid
+	config_foreach dhcp_match_add match
 	config_foreach dhcp_domain_add domain
 	config_foreach dhcp_hostrecord_add hostrecord
 	config_foreach dhcp_relay_add relay