Re: [9front] WANTED: ip based filtering of incoming connections

[Jacob Moody <moody@posixcafe.org>]

On 7/25/24 22:57, sl@stanleylieber.com wrote:
>>> Did you verify it was working with just a single ip address or two?  I
>>> am thinking perhaps you ran in to some arbitrary buffer limit.
>>
>> even with only one ip address it has no effect.
> 
> the while loop seems useless. if i run this on the command line and never
> interrupt it, it just keeps going, and continues to block connections from
> this one ip:
> 
> 	; aux/dial 'ipmux!vers=4;src=168.235.81.125&255.255.255.255' >/dev/null
> 
> but the original problem i reported still holds true: if i fork it to the
> background by placing an & at the end of the line, it exist immediately.
> 
> and you're right, even just running it on the command line and not
> interrupting it, with a longer list of ip addresses, it has no effect:
> 
> 	; aux/dial 'ipmux!vers=4;src=47.128.0.0&255.252.0.0|52.230.152.0&255.255.255.0|64.249.68.0&255.255.255.0|64.249.79.0&255.255.255.0|64.249.83.0&255.255.255.0|85.208.96.0&255.255.255.0|156.59.198.0&255.255.255.0|168.235.81.125&255.255.255.255' >/dev/null
> 
> it never exits, it just doesn't seem to do anything.
> 
> sl

Sorry, my memory betrayed me here and I got all sorts of things wrong.
Testing things myself I see the same behavior you see, so forget the rc loop.

The issue with dial exiting immediately when backgrounded is because it reads stdin,
if you pass dial a -e flag it will ignore stdin and & will work as intended.

As for the large lines not working, /sys/src/libc/9sys/dial.c has some hard coded
limits and a quick scan makes me think we're capped at Maxstring (128).

Sorry,
moody