Re: [net-next PATCH v5 0/3] net: reserve ports for applicationsusing fixed port numbers
From: Bill Fink
Date: Sun Feb 21 2010 - 01:24:01 EST
On Sat, 20 Feb 2010, Octavian Purdila wrote:
> On Saturday 20 February 2010 10:11:40 you wrote:
> > Octavian Purdila wrote:
> > > This patch introduces /proc/sys/net/ipv4/ip_local_reserved_ports which
> > > allows users to reserve ports for third-party applications.
> > >
> > > The reserved ports will not be used by automatic port assignments
> > > (e.g. when calling connect() or bind() with port number 0). Explicit
> > > port allocation behavior is unchanged.
> > >
> > > Changes from the previous version:
> > > - switch the /proc entry format to coma separated list of range ports
> > > - treat -EFAULT just like any other error and acknowledge written values
> > > - use isdigit() in proc_get_ulong
> > >
> > > Octavian Purdila (3):
> > > sysctl: refactor integer handling proc code
> > > sysctl: add proc_do_large_bitmap
> > > net: reserve ports for applications using fixed port numbers
> >
> > Hi,
> >
> > This version looks fine for me, but I need to give them a test, and
> > I will put feedbacks asap. Thanks for your work!
> >
> > Still two things:
> >
> > 1) bitops are always atomic on every arch, right? If yes, then ok.
>
> AFAIK, yes.
>
> > 2) I hope you could add some documentation to show the relations
> > between ip_local_port_range and ip_local_reserved_ports.
> >
>
> How does this sound:
>
> ip_local_reserved_ports - list of comma separated ranges
> Specify the ports which are reserved for known third-party
> applications. These ports will not be used by automatic port
> assignments (e.g. when calling connect() or bind() with port
> number 0). Explicit port allocation behavior is unchanged.
>
> The format used for both input and output is a comma separated
> list of ranges (e.g. "1,2-4,10-10" for ports 1, 2, 3, 4 and
> 10). Writing to the file will clear all previously reserved
> ports and update the current list with the one given in the
> input.
>
> Note that ip_local_port_range and ip_local_port_range settings
Change second ip_local_port_range to ip_local_reserved_ports.
-Bill
> are independent and both are considered by the kernel when
> determining which ports are available for automatic port
> assignments.
>
> You can reserve ports which are not in the current
> ip_local_port_range, e.g.:
>
> $ cat /proc/sys/net/ipv4/ip_local_port_range
> 32000 61000
> $ cat /proc/sys/net/ipv4/ip_local_reserved_ports
> 8080,9148
>
> although this is redundant. However such a setting is useful
> if later the port range is changed to a value that will
> include the reserved ports.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/