Porting pf from current OpenBSD to FreeBSD

[Алексей Прокопчук]

Greetings!

Now I'm trying to port the current pf from OpenBSD to current FreeBSD. 
As a separate module this time, without any changes in the FreeBSD 
kernel code. There are quite lot of inconsistencies - counters, tasks, 
crypto, routing domains, mbuf, inpcb and others.
In your opinion, what is the best way to solve the inconsistencies with 
the current kernel? In case of inpcb I've created a structure containing 
the inpcb itself and additional members, which are OpenBSD - specific. 
In case of routing domains I've decided to always use the default value 
0 and make a function stub rtable_l2(), which returns 0 in all cases. In 
case of the tasks I intend to use tasqueue "swi" for the enqueue task.

I have almost no experience in the development of the FreeBSD kernel, 
perhaps you could give me the cue as to where I'm making mistakes.