Function pf_state_insert

freebsd/netpfil/pf/pf.c:1257–1313

}

int
pf_state_insert(struct pfi_kkif *kif, struct pf_state_key *skw,
    struct pf_state_key *sks, struct pf_state *s)
{
	struct pf_idhash *ih;
	struct pf_state *cur;
	int error;

	KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
	    ("%s: sks not pristine", __func__));
	KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
	    ("%s: skw not pristine", __func__));
	KASSERT(s->refs == 0, ("%s: state not pristine", __func__));

	s->kif = kif;

	if (s->id == 0 && s->creatorid == 0) {
		/* XXX: should be atomic, but probability of collision low */
		if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID)
			V_pf_stateid[curcpu] = 1;
		s->id |= (uint64_t )curcpu << PFID_CPUSHIFT;
		s->id = htobe64(s->id);
		s->creatorid = V_pf_status.hostid;
	}

	/* Returns with ID locked on success. */
	if ((error = pf_state_key_attach(skw, sks, s)) != 0)
		return (error);

	ih = &V_pf_idhash[PF_IDHASH(s)];
	PF_HASHROW_ASSERT(ih);
	LIST_FOREACH(cur, &ih->states, entry)
		if (cur->id == s->id && cur->creatorid == s->creatorid)
			break;

	if (cur != NULL) {
		PF_HASHROW_UNLOCK(ih);
		if (V_pf_status.debug >= PF_DEBUG_MISC) {
			printf("pf: state ID collision: "
			    "id: %016llx creatorid: %08x\n",
			    (unsigned long long)be64toh(s->id),
			    ntohl(s->creatorid));
		}
		pf_detach_state(s);
		return (EEXIST);
	}
	LIST_INSERT_HEAD(&ih->states, s, entry);
	/* One for keys, one for ID hash. */
	refcount_init(&s->refs, 2);

	counter_u64_add(V_pf_status.fcounters[FCNT_STATE_INSERT], 1);
	if (V_pfsync_insert_state_ptr != NULL)
		V_pfsync_insert_state_ptr(s);

	/* Returns locked. */
	return (0);
}