base-files: use cidr for config_generate

Generate network configuration replacing netmask with CIDR.

Depends on:
https://github.com/openwrt/openwrt/pull/13765

Using CIDR provides the following advantages:
* Consolidate notation for IPv4 and IPv6 addresses.
* Consolidate notation for IP addresses and routing targets.
* Simplify network configuration and troubleshooting.
* Follow the transition from net-tools to iproute2.

Resulting configuration example:
```
config interface 'loopback'
	option device 'lo'
	option proto 'static'
	list ipaddr '127.0.0.1/8'

config interface 'lan'
	option device 'br-lan'
	option proto 'static'
	list ipaddr '192.168.1.1/24'
```

Signed-off-by: Vladislav Grigoryev <vg.aetera@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/13780
Signed-off-by: Robert Marko <robimarko@gmail.com>

diff --git a/package/base-files/files/bin/config_generate b/package/base-files/files/bin/config_generate
index fecf82fcaa6014064c0f95a7b35e0e18ffd108c3..7507aa612c0dd8bc522a74c3d5cd9a625a6f9dae 100755 (executable)
--- a/package/base-files/files/bin/config_generate
+++ b/package/base-files/files/bin/config_generate
@@ -3,6 +3,7 @@
 CFG=/etc/board.json
 
 . /usr/share/libubox/jshn.sh
+. /lib/functions/ipv4.sh
 
 [ -s $CFG ] || /bin/board_detect || exit 1
 [ -s /etc/config/network -a -s /etc/config/system ] && exit 0
@@ -42,8 +43,7 @@ generate_static_network() {
                set network.loopback='interface'
                set network.loopback.device='lo'
                set network.loopback.proto='static'
-               set network.loopback.ipaddr='127.0.0.1'
-               set network.loopback.netmask='255.0.0.0'
+               add_list network.loopback.ipaddr='127.0.0.1/8'
        EOF
                [ -e /proc/sys/net/ipv6 ] && {
                        uci -q batch <<-EOF
@@ -160,18 +160,19 @@ generate_network() {
 
        case "$protocol" in
                static)
-                       local ipad
+                       local ipad netm prefix
                        case "$1" in
                                lan) ipad=${ipaddr:-"192.168.1.1"} ;;
                                *) ipad=${ipaddr:-"192.168.$((addr_offset++)).1"} ;;
                        esac
 
                        netm=${netmask:-"255.255.255.0"}
+                       str2ip netm "$netm"
+                       netmask2prefix prefix "$netm"
 
                        uci -q batch <<-EOF
                                set network.$1.proto='static'
-                               set network.$1.ipaddr='$ipad'
-                               set network.$1.netmask='$netm'
+                               add_list network.$1.ipaddr='$ipad/$prefix'
                        EOF
                        [ -e /proc/sys/net/ipv6 ] && uci set network.$1.ip6assign='60'
                ;;