Match & target structure history in 2.4.28 and 2.6.x series

Match & target structure history in 2.4.28 and 2.6.x series

[Jonas Berlin]

In the hope that it will help people write matches & targets that are compatible with not only the newest version of linux, I wrote a page showing the changes to the match & target structs used in kernel code in the 2.6 series since 2.4.28:

http://xkr47.outerspace.dyndns.org/netfilter/match_and_target_structure_history.html

There has been quite a lot of changes in fact, and often ipv6 changes have appeared later than ipv4 changes.

I also included the transition from ipt_* and ip6t_* structs to xt_* structs in 2.6.16.

I'll try to write some skeleton examples later on how to do the basic backwards compatibility.. if I have time.. meanwhile, you get some idea by looking at this example.. check the #if statements:

http://svn.netfilter.org/cgi-bin/viewcvs.cgi/trunk/patch-o-matic-ng/patchlets/set/linux-2.6/net/ipv4/netfilter/ipt_set.c?view=markup

- xkr47

-- 
 "if I'd make up my own definitions, unrational would be the the end
  result after someone unrationalized something i.e. actively worked
  to cut down on rationality, whereas irrational would be more a
  result of laziness or lack of skill"
                - me, 23.11.2006

Re: Match & target structure history in 2.4.28 and 2.6.x series

[Jan Engelhardt]

>In the hope that it will help people write matches & targets that are 
>compatible with not only the newest version of linux, I wrote a page 
>showing the changes to the match & target structs used in kernel code 
>in the 2.6 series since 2.4.28:

You could add 2.6.20-rc4 (to become 2.6.20).


	-`J'
-- 

Re: Match & target structure history in 2.4.28 and 2.6.x series

[Jonas Berlin]

Jan Engelhardt wrote:
>> In the hope that it will help people write matches & targets that are 
>> compatible with not only the newest version of linux, I wrote a page 
>> showing the changes to the match & target structs used in kernel code 
>> in the 2.6 series since 2.4.28:
> 
> You could add 2.6.20-rc4 (to become 2.6.20).

Do you mean I should add "(to become 2.6.20)" after 2.6.20-rc4 ? I have
2.6.20-rc4 in there already.. :)

- xkr47

Re: Match & target structure history in 2.4.28 and 2.6.x series

[Jan Engelhardt]

>>In the hope that it will help people write matches & targets that are 
>>compatible with not only the newest version of linux, I wrote a page 
>>showing the changes to the match & target structs used in kernel code 
>>in the 2.6 series since 2.4.28:
>
>You could add 2.6.20-rc4 (to become 2.6.20).

Oh right. Well, I just thought of this peculiarity in 2.6.20:

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
#    define nfmark mark
#endif

void foobar(struct sk_buff *skb) {
    printk("Mark is %d\n", skb->nfmark);
}


	-`J'
-- 

Re: Match & target structure history in 2.4.28 and 2.6.x series

[Jonas Berlin]

Jan Engelhardt wrote:
>>> In the hope that it will help people write matches & targets that are 
>>> compatible with not only the newest version of linux, I wrote a page 
>>> showing the changes to the match & target structs used in kernel code 
>>> in the 2.6 series since 2.4.28:
>> You could add 2.6.20-rc4 (to become 2.6.20).
> 
> Oh right. Well, I just thought of this peculiarity in 2.6.20:
> 
> #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
> #    define nfmark mark
> #endif
> 
> void foobar(struct sk_buff *skb) {
>     printk("Mark is %d\n", skb->nfmark);
> }

Oh right.. well I haven't covered structures other than the *_match and
*_target ones.. I'm sure there's a lot else out there that could/should
be documented in the same way.. :) Maybe I could create a separate page
for sk_buff..?