package: avoid the use of eval to parse ipcalc.sh output

Add a function 'ipcalc' to /lib/functions.sh that sets variables more
safely using export.
With this new function, dnsmasq also handles the return value of ipcalc
correctly.

Fixes: e4bd3de1be8e ("dnsmasq: refuse to add empty DHCP range")
Co-Authored-By: Philip Prindeville <[email protected]>
Signed-off-by: Leon M. Busch-George <[email protected]>

package/base-files/files/lib/functions.sh

@@ -315,6 +315,11 @@ include() {
 	done
 }
 
+ipcalc() {
+	set -- $(ipcalc.sh "$@")
+	[ $? -eq 0 ] && export -- "$@"
+}
+
 find_mtd_index() {
 	local PART="$(grep "\"$1\"" /proc/mtd | awk -F: '{print $1}')"
 	local INDEX="${PART##mtd}"

package/network/config/netifd/Makefile

@@ -1,7 +1,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=netifd
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(PROJECT_GIT)/project/netifd.git

package/network/config/netifd/files/lib/netifd/dhcp.script

@@ -18,13 +18,13 @@ setup_interface () {
 	proto_add_ipv4_address "$ip" "${subnet:-255.255.255.0}"
 	# TODO: apply $broadcast
 
-	local ip_net
-	eval "$(ipcalc.sh "$ip/$mask")";ip_net="$NETWORK"
+	local ip_net IP PREFIX NETWORK NETMASK BROADCAST
+	ipcalc "$ip/$mask" && ip_net="$NETWORK"
 
 	local i
 	for i in $router; do
 		local gw_net
-		eval "$(ipcalc.sh "$i/$mask")";gw_net="$NETWORK"
+		ipcalc "$i/$mask" && gw_net="$NETWORK"
 
 		[ "$ip_net" != "$gw_net" ] && proto_add_ipv4_route "$i" 32 "" "$ip"
 		proto_add_ipv4_route 0.0.0.0 0 "$i" "$ip"

package/network/ipv6/6rd/Makefile

@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=6rd
-PKG_RELEASE:=12
+PKG_RELEASE:=13
 PKG_LICENSE:=GPL-2.0
 
 include $(INCLUDE_DIR)/package.mk

package/network/ipv6/6rd/files/6rd.sh

@@ -40,8 +40,8 @@ proto_6rd_setup() {
 
 	# Determine the relay prefix.
 	local ip4prefixlen="${ip4prefixlen:-0}"
-	local ip4prefix
-	eval "$(ipcalc.sh "$ipaddr/$ip4prefixlen")";ip4prefix=$NETWORK
+	local ip4prefix IP PREFIX NETWORK NETMASK BROADCAST
+	ipcalc "$ipaddr/$ip4prefixlen" && ip4prefix="$NETWORK"
 
 	# Determine our IPv6 address.
 	local ip6subnet=$(6rdcalc "$ip6prefix/$ip6prefixlen" "$ipaddr/$ip4prefixlen")

package/network/services/dnsmasq/Makefile

@@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
 PKG_NAME:=dnsmasq
 PKG_UPSTREAM_VERSION:=2.89
 PKG_VERSION:=$(subst test,~~test,$(subst rc,~rc,$(PKG_UPSTREAM_VERSION)))
-PKG_RELEASE:=4
+PKG_RELEASE:=5
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_UPSTREAM_VERSION).tar.xz
 PKG_SOURCE_URL:=https://thekelleys.org.uk/dnsmasq/

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

@@ -1,6 +1,8 @@
 #!/bin/sh /etc/rc.common
 # Copyright (C) 2007-2012 OpenWrt.org
 
+. /lib/functions.sh
+
 START=19
 
 USE_PROCD=1
@@ -509,7 +511,6 @@ dhcp_boot_add() {
 	dhcp_option_add "$cfg" "$networkid" "$force"
 }
 
-
 dhcp_add() {
 	local cfg="$1"
 	local dhcp6range="::"
@@ -587,7 +588,7 @@ dhcp_add() {
 	fi
 
 	# make sure the DHCP range is not empty
-	if [ "$dhcpv4" != "disabled" ] && eval "$(ipcalc.sh "${subnet%%/*}" "$netmask" "$start" "$limit")" ; then
+	if [ "$dhcpv4" != "disabled" ] && ipcalc "${subnet%%/*}" "$netmask" "$start" "$limit" ; then
 		[ "$dynamicdhcpv4" = "0" ] && END="static"
 
 		xappend "--dhcp-range=$tags$nettag$START,$END,$NETMASK,$leasetime${options:+ $options}"