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

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

[Andreas Henriksson]

Suggested patch for allowing netmask to be specified in dotted quad format.
See http://bugs.debian.org/357172

(Known problem: this will not prevent some invalid syntaxes,
ie. "255.0.255.0" will be treated as "255.255.255.0")

Comments? Suggestions? Improvements?

Signed-off-by: Andreas Henriksson <andreas@fatal.se>


diff --git a/lib/utils.c b/lib/utils.c
index 4c42dfd..277ab45 100644
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -47,6 +47,25 @@ int get_integer(int *val, const char *arg, int base)
 	return 0;
 }
 
+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 = addr.data[0]; mask; mask >>= 1)
+			(*val)++;
+		return 0;
+	}
+
+	return -1;
+}
+
 int get_unsigned(unsigned *val, const char *arg, int base)
 {
 	unsigned long res;
@@ -304,7 +323,8 @@ 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;
 			}

-- 
Regards,
Andreas Henriksson

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

[Stephen Hemminger]

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
> 
> (Known problem: this will not prevent some invalid syntaxes,
> ie. "255.0.255.0" will be treated as "255.255.255.0")
> 
> Comments? Suggestions? Improvements?

Fix the bug you mentioned?

/* 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]);
	if (host == 0 || ~host == 0)
		return 0;

	return (host & (host + 1)) == 0;
}

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

[Andreas Henriksson]

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
> > 
> > (Known problem: this will not prevent some invalid syntaxes,
> > ie. "255.0.255.0" will be treated as "255.255.255.0")
> > 
> > Comments? Suggestions? Improvements?
> 
> Fix the bug you mentioned?
> 
> [... snip example code ...]

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. 

Signed-off-by: Andreas Henriksson <andreas@fatal.se>

diff --git a/lib/utils.c b/lib/utils.c
index 4c42dfd..b4a6125 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 = 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;
 			}


-- 
Regards,
Andreas Henriksson

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

[Andreas Henriksson]

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;
 			}




-- 
Regards,
Andreas Henriksson

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

[Stephen Hemminger]

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>

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

[Andreas Henriksson]

On Tue, Dec 11, 2007 at 05:14:06PM -0800, Stephen Hemminger wrote:
> On Sun, 09 Dec 2007 18:10:22 +0100
> Andreas Henriksson <andreas@fatal.se> wrote:
> > I think both previous patches where broken on big-endian platforms.
> > Here's an updated patch again. I'm very sorry for the inconvenience!
[...]
> > +		*val=0;
> > +		for (mask = ntohl(addr.data[0]); mask; mask <<= 1)
> > +			(*val)++;
[...]
> 
> applied
> 

Just to make sure.... It looks on git.kernel.org like you applied the wrong
patch. (Maybe you just haven't pushed out the latest changes there yet.)
Please double-check that you actually applied the latest version (which is
the one in the mail you replied "applied" to, important part quoted above). 


Additionally, there's still a couple of trivial patches pending in
the "patches" branch of 
git://git.debian.org/git/collab-maint/pkg-iproute.git

Please see the original thread[1], where Patrick McHarding had some concerns
about one of the patches. It's exactly the same changes you made in commit
660818498d0f5a3f52c05355a3e82c23f670fcc1 [2] though, so I don't really see the
problem. I have an additional patch[3] available, that makes MAX_ROUNDS
configurable which Patrick requested.

Please comment on the way forward there....


[1]: http://www.spinics.net/lists/netdev/msg44800.html
[2]: Where the comment seems to be wrong about "Limit ip route flush...",
     since it's actually "ip neigh flush" that's being modified.
[3]: I have a slightly updated patch, but it's basically the same as
     http://www.spinics.net/lists/netdev/msg45080.html
	 Will send updated version if the patches it's based on goes in.

-- 
Regards,
Andreas Henriksson

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

[Stephen Hemminger]

On Wed, 12 Dec 2007 12:55:13 +0100
Andreas Henriksson <andreas@fatal.se> wrote:

> On Tue, Dec 11, 2007 at 05:14:06PM -0800, Stephen Hemminger wrote:
> > On Sun, 09 Dec 2007 18:10:22 +0100
> > Andreas Henriksson <andreas@fatal.se> wrote:
> > > I think both previous patches where broken on big-endian platforms.
> > > Here's an updated patch again. I'm very sorry for the inconvenience!
> [...]
> > > +		*val=0;
> > > +		for (mask = ntohl(addr.data[0]); mask; mask <<= 1)
> > > +			(*val)++;
> [...]
> > 
> > applied
> > 
> 
> Just to make sure.... It looks on git.kernel.org like you applied the wrong
> patch. (Maybe you just haven't pushed out the latest changes there yet.)
> Please double-check that you actually applied the latest version (which is
> the one in the mail you replied "applied" to, important part quoted above). 

Actually, I took your logic and moved it to a new function:

static unsigned cidr(const inet_prefix *addr)
{
	unsigned bits = 0;
	u_int32_t mask;

	for (mask = ntohl(addr->data[0]); mask; mask <<= 1)
		++bits;

	return bits;
}
-- 
Stephen Hemminger <shemminger@linux-foundation.org>