As already wroted on old post:
- for security accept only from /12 to /32 prefix. /11 or less on IPv4 is too much big for be true…
Some procedures for check the subnet mask:
http://forum.mikrotik.com/t/rextended-fragments-of-snippets/151033/1
{
:local source 10.31.42.56/16
:if ([:len [:find $source “/”]] = 0) do={:set source “$source/32”}
:local ip [:toip [:pick $source 0 [:find $source “/”]]]
:local prefix [:tonum [:pick $source ([:find $source “/”] + 1) [:len $source]]]
:local submask (255.255.255.255<<(32 - $prefix))
:local network ($ip & $submask)
:put “$source = $network/$prefix”
}
{
:local source 10.31.42.56
:if ([:len [:find $source “/”]] = 0) do={:set source “$source/32”}
:local ip [:toip [:pick $source 0 [:find $source “/”]]]
:local prefix [:tonum [:pick $source ([:find $source “/”] + 1) [:len $source]]]
:local submask (255.255.255.255<<(32 - $prefix))
:local network ($ip & $submask)
:put “$source = $network/$prefix”
}