RPZ zone name label length limit

[Ray Bellis]

On 29/06/2017 19:14, Tony Finch wrote:

> Amusingly when I was trying this to see how long it is I found a bug in
> iOS dig :-)
> 
> $ dig +noall +comment information.uzmzudseodc2fjpyi6mjcxndiymtuzmzufazdseyi6swh58fmodc2fjqxoc2fjp.com
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 36667
> ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
> $ dig +noall +comment information.uzmzudseodc2fjpyi6mjcxndiymtuzmzufazdseyi6swh58fmodc2fjqxoc2fjpx.com
> dig: 'information.uzmzudseodc2fjpyi6mjcxndiymtuzmzufazdseyi6swh58fmodc2fjqxoc2fjpx.com' is not a legal name (label too long)

The iOS port of 'dig' uses the exact same underlying code as far as
possible.   The UI spawns a separate thread in which dig's main()
function is invoked, and uses batch mode to pass search terms in on
stdin, and then traps the stdout (using `funopen`) to display it.

The command line version of 'dig' apparently does a forceable exit when
this condition is detected, treating this as a fatal error.

I found many of the cases in which an error can cause batch mode to die
(thereby killing the UI too) but apparently not all of them :(.

Ray