[RFC v2] extensions: libxt_TOS: Add translation to nft

[RFC v2] extensions: libxt_TOS: Add translation to nft

[Gargi Sharma]

Add translation for TOS to nftables. TOS is deprecated
ans DSCP is ued in place of it. The first 6 bits of
TOS specify the DSCP value.

Examples:

$ iptables-translate -t mangle -A PREROUTING -p TCP --dport 22 -j TOS --set-tos 0x10
nft add rule ip mangle PREROUTING tcp dport 22 counter  ip6 dscp set 0x04

Signed-off-by: Gargi Sharma <gs051095@gmail.com>
---
Changes in v2:
	- Added DSCP conversion.
---
 extensions/libxt_TOS.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/extensions/libxt_TOS.c b/extensions/libxt_TOS.c
index cef5876..f284d83 100644
--- a/extensions/libxt_TOS.c
+++ b/extensions/libxt_TOS.c
@@ -183,6 +183,30 @@ static void tos_tg_save(const void *ip, const struct xt_entry_target *target)
 	printf(" --set-tos 0x%02x/0x%02x", info->tos_value, info->tos_mask);
 }
 
+static int tos_xlate(struct xt_xlate *xl,
+		     const struct xt_xlate_tg_params *params)
+{
+	const struct ipt_tos_target_info *info =
+			(struct ipt_tos_target_info *) params->target->data;
+
+	__u8 dscp = (info->tos)>>2;
+	xt_xlate_add(xl, "ip dscp set 0x%02x", dscp);
+
+	return 1;
+}
+
+static int tos_xlate6(struct xt_xlate *xl,
+		     const struct xt_xlate_tg_params *params)
+{
+	const struct ipt_tos_target_info *info =
+			(struct ipt_tos_target_info *) params->target->data;
+
+	__u8 dscp = (info->tos)>>2;
+	xt_xlate_add(xl, " ip6 dscp set 0x%02x", dscp);
+
+	return 1;
+}
+
 static struct xtables_target tos_tg_reg[] = {
 	{
 		.version       = XTABLES_VERSION,
@@ -197,6 +221,7 @@ static struct xtables_target tos_tg_reg[] = {
 		.x6_parse      = tos_tg_parse_v0,
 		.x6_fcheck     = tos_tg_check,
 		.x6_options    = tos_tg_opts_v0,
+		.xlate	       = tos_xlate,
 	},
 	{
 		.version       = XTABLES_VERSION,
@@ -211,6 +236,7 @@ static struct xtables_target tos_tg_reg[] = {
 		.x6_parse      = tos_tg_parse,
 		.x6_fcheck     = tos_tg_check,
 		.x6_options    = tos_tg_opts,
+		.xlate	       = tos_xlate6,
 	},
 };
 
-- 
2.7.4

Re: [RFC v2] extensions: libxt_TOS: Add translation to nft

[Pablo Neira Ayuso]

On Wed, Mar 29, 2017 at 12:20:18AM +0530, Gargi Sharma wrote:
> Add translation for TOS to nftables. TOS is deprecated
> ans DSCP is ued in place of it. The first 6 bits of
> TOS specify the DSCP value.
> 
> Examples:
> 
> $ iptables-translate -t mangle -A PREROUTING -p TCP --dport 22 -j TOS --set-tos 0x10
> nft add rule ip mangle PREROUTING tcp dport 22 counter  ip6 dscp set 0x04

Applied, but I had to mangle this patch.

Coding style is not correct, for two reason, see below.

> diff --git a/extensions/libxt_TOS.c b/extensions/libxt_TOS.c
> index cef5876..f284d83 100644
> --- a/extensions/libxt_TOS.c
> +++ b/extensions/libxt_TOS.c
> @@ -183,6 +183,30 @@ static void tos_tg_save(const void *ip, const struct xt_entry_target *target)
>  	printf(" --set-tos 0x%02x/0x%02x", info->tos_value, info->tos_mask);
>  }
>  
> +static int tos_xlate(struct xt_xlate *xl,
> +		     const struct xt_xlate_tg_params *params)
> +{
> +	const struct ipt_tos_target_info *info =
> +			(struct ipt_tos_target_info *) params->target->data;
> +
^^^
No need for new line here.

> +	__u8 dscp = (info->tos)>>2;

Missing space here between declaration and code.
You can just use uint8_t from stdint.h BTW.
And the parens are not required, plus missing spaces:

	__u8 dscp = info->tos >> 2;

Re: [RFC v2] extensions: libxt_TOS: Add translation to nft

[Pablo Neira Ayuso]

On Wed, Mar 29, 2017 at 12:20:18AM +0530, Gargi Sharma wrote:
> diff --git a/extensions/libxt_TOS.c b/extensions/libxt_TOS.c
> index cef5876..f284d83 100644
> --- a/extensions/libxt_TOS.c
> +++ b/extensions/libxt_TOS.c
> @@ -183,6 +183,30 @@ static void tos_tg_save(const void *ip, const struct xt_entry_target *target)
[...]
> +	xt_xlate_add(xl, "ip dscp set 0x%02x", dscp);
[...]
> +	xt_xlate_add(xl, " ip6 dscp set 0x%02x", dscp);
                          ^
And there's a space here. You have to be more careful.

Thanks!

Re: [RFC v2] extensions: libxt_TOS: Add translation to nft

[Gargi Sharma]

On Fri, Apr 7, 2017 at 4:13 AM, Pablo Neira Ayuso <pablo@netfilter.org> wrote:
> On Wed, Mar 29, 2017 at 12:20:18AM +0530, Gargi Sharma wrote:
>> Add translation for TOS to nftables. TOS is deprecated
>> ans DSCP is ued in place of it. The first 6 bits of
>> TOS specify the DSCP value.
>>
>> Examples:
>>
>> $ iptables-translate -t mangle -A PREROUTING -p TCP --dport 22 -j TOS --set-tos 0x10
>> nft add rule ip mangle PREROUTING tcp dport 22 counter  ip6 dscp set 0x04
>
> Applied, but I had to mangle this patch.
>
> Coding style is not correct, for two reason, see below.
>
>> diff --git a/extensions/libxt_TOS.c b/extensions/libxt_TOS.c
>> index cef5876..f284d83 100644
>> --- a/extensions/libxt_TOS.c
>> +++ b/extensions/libxt_TOS.c
>> @@ -183,6 +183,30 @@ static void tos_tg_save(const void *ip, const struct xt_entry_target *target)
>>       printf(" --set-tos 0x%02x/0x%02x", info->tos_value, info->tos_mask);
>>  }
>>
>> +static int tos_xlate(struct xt_xlate *xl,
>> +                  const struct xt_xlate_tg_params *params)
>> +{
>> +     const struct ipt_tos_target_info *info =
>> +                     (struct ipt_tos_target_info *) params->target->data;
>> +
> ^^^
> No need for new line here.
>
>> +     __u8 dscp = (info->tos)>>2;
>
> Missing space here between declaration and code.
> You can just use uint8_t from stdint.h BTW.
> And the parens are not required, plus missing spaces:
>
>         __u8 dscp = info->tos >> 2;

In hindsight, I should have ran checkpatch before submitting this
patch. I forgot, and would not do this in future.

Thanks,
Gargi

Re: [RFC v2] extensions: libxt_TOS: Add translation to nft

[Gargi Sharma]

On Fri, Apr 7, 2017 at 4:19 AM, Pablo Neira Ayuso <pablo@netfilter.org> wrote:
>
> On Wed, Mar 29, 2017 at 12:20:18AM +0530, Gargi Sharma wrote:
> > diff --git a/extensions/libxt_TOS.c b/extensions/libxt_TOS.c
> > index cef5876..f284d83 100644
> > --- a/extensions/libxt_TOS.c
> > +++ b/extensions/libxt_TOS.c
> > @@ -183,6 +183,30 @@ static void tos_tg_save(const void *ip, const struct xt_entry_target *target)
> [...]
> > +     xt_xlate_add(xl, "ip dscp set 0x%02x", dscp);
> [...]
> > +     xt_xlate_add(xl, " ip6 dscp set 0x%02x", dscp);
>                           ^
> And there's a space here. You have to be more careful.
>
> Thanks!

Point noted. Will be more careful in future. :)

Thanks,
Gargi