Re: [PATCH] iproute2: support dotted-quad netmask notation.

[Stephen Hemminger <shemminger@linux-foundation.org>]

On Sun, 09 Dec 2007 18:10:22 +0100
Andreas Henriksson <andreas@fatal.se> wrote:

> 
> On lör, 2007-12-08 at 00:41 +0100, Andreas Henriksson wrote:
> > On tor, 2007-12-06 at 11:53 -0800, Stephen Hemminger wrote:
> > > On Tue, 4 Dec 2007 14:58:18 +0100
> > > Andreas Henriksson <andreas@fatal.se> wrote:
> > > 
> > > > Suggested patch for allowing netmask to be specified in dotted quad format.
> > > > See http://bugs.debian.org/357172
> > > > 
> > Updated patch, added your netmask validation code but without the check
> > that made 0.0.0.0 (default) and 255.255.255.255 (one address) invalid
> > netmasks as they are permitted in CIDR format. 
> 
> I think both previous patches where broken on big-endian platforms.
> Here's an updated patch again. I'm very sorry for the inconvenience!
> 
> Signed-off-by: Andreas Henriksson <andreas@fatal.se>
> 
> 
> diff --git a/lib/utils.c b/lib/utils.c
> index 4c42dfd..bb88cf7 100644
> --- a/lib/utils.c
> +++ b/lib/utils.c
> @@ -47,6 +47,41 @@ int get_integer(int *val, const char *arg, int base)
>  	return 0;
>  }
>  
> +/* a valid netmask must be 2^n - 1 (n = 1..31) */
> +static int is_valid_netmask(const inet_prefix *addr)
> +{
> +        uint32_t host;
> +
> +        if (addr->family != AF_INET)
> +                return 0;
> +
> +        host = ~ntohl(addr->data[0]);
> +
> +        return (host & (host + 1)) == 0;
> +}
> +
> +static int get_netmask(unsigned *val, const char *arg, int base)
> +{
> +	inet_prefix addr;
> +
> +	if (!get_unsigned(val, arg, base))
> +		return 0;
> +
> +	/* try coverting dotted quad to CIDR */
> +	if (!get_addr_1(&addr, arg, AF_INET)) {
> +		u_int32_t mask;
> +
> +		*val=0;
> +		for (mask = ntohl(addr.data[0]); mask; mask <<= 1)
> +			(*val)++;
> +
> +		if (is_valid_netmask(&addr))
> +			return 0;
> +	}
> +
> +	return -1;
> +}
> +
>  int get_unsigned(unsigned *val, const char *arg, int base)
>  {
>  	unsigned long res;
> @@ -304,7 +339,8 @@ int get_prefix_1(inet_prefix *dst, char *arg, int family)
>  				dst->bitlen = 32;
>  		}
>  		if (slash) {
> -			if (get_unsigned(&plen, slash+1, 0) || plen > dst->bitlen) {
> +			if (get_netmask(&plen, slash+1, 0)
> +					|| plen > dst->bitlen) {
>  				err = -1;
>  				goto done;
>  			}
> 
> 
> 
> 

applied


-- 
Stephen Hemminger <shemminger@linux-foundation.org>