#!/bin/sh
[ "$(uci get network.globals.ula_prefix)" != "auto" ] && exit 0
-# Sometimes results are empty, therefore try until it works...
-local r1 r2 r3
-while [ -z "$r1" -o -z "$r2" -o -z "$r3" ]; do
- r1=$(printf "%02x" $(($(</dev/urandom tr -dc 0-9 | dd bs=9 count=1) % 256)))
- r2=$(printf "%01x" $(($(</dev/urandom tr -dc 0-9 | dd bs=9 count=1) % 65536)))
- r3=$(printf "%01x" $(($(</dev/urandom tr -dc 0-9 | dd bs=9 count=1) % 65536)))
-done
+
+r1=$(dd if=/dev/urandom bs=1 count=1 |hexdump -e '1/1 "%02x"')
+r2=$(dd if=/dev/urandom bs=2 count=1 |hexdump -e '2/1 "%02x"')
+r3=$(dd if=/dev/urandom bs=2 count=1 |hexdump -e '2/1 "%02x"')
uci -q batch <<-EOF >/dev/null
set network.globals.ula_prefix=fd$r1:$r2:$r3::/48