Function key_register

freebsd/netipsec/key.c:7070–7217

* SADB_REGISTER processing. * If SATYPE_UNSPEC has been passed as satype, only return sabd_supported. * receive * * from the ikmpd, and register a socket to send PF_KEY messages, * and send * * to KMD by PF_KEY. * If socket is detached, must free from regnode. * * m will always be freed. */

 * m will always be freed.
 */
static int
key_register(struct socket *so, struct mbuf *m, const struct sadb_msghdr *mhp)
{
	struct secreg *reg, *newreg = NULL;

	IPSEC_ASSERT(so != NULL, ("null socket"));
	IPSEC_ASSERT(m != NULL, ("null mbuf"));
	IPSEC_ASSERT(mhp != NULL, ("null msghdr"));
	IPSEC_ASSERT(mhp->msg != NULL, ("null msg"));

	/* check for invalid register message */
	if (mhp->msg->sadb_msg_satype >= sizeof(V_regtree)/sizeof(V_regtree[0]))
		return key_senderror(so, m, EINVAL);

	/* When SATYPE_UNSPEC is specified, only return sabd_supported. */
	if (mhp->msg->sadb_msg_satype == SADB_SATYPE_UNSPEC)
		goto setmsg;

	/* check whether existing or not */
	REGTREE_LOCK();
	LIST_FOREACH(reg, &V_regtree[mhp->msg->sadb_msg_satype], chain) {
		if (reg->so == so) {
			REGTREE_UNLOCK();
			ipseclog((LOG_DEBUG, "%s: socket exists already.\n",
				__func__));
			return key_senderror(so, m, EEXIST);
		}
	}

	/* create regnode */
	newreg =  malloc(sizeof(struct secreg), M_IPSEC_SAR, M_NOWAIT|M_ZERO);
	if (newreg == NULL) {
		REGTREE_UNLOCK();
		ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
		return key_senderror(so, m, ENOBUFS);
	}

	newreg->so = so;
	((struct keycb *)sotorawcb(so))->kp_registered++;

	/* add regnode to regtree. */
	LIST_INSERT_HEAD(&V_regtree[mhp->msg->sadb_msg_satype], newreg, chain);
	REGTREE_UNLOCK();

  setmsg:
    {
	struct mbuf *n;
	struct sadb_msg *newmsg;
	struct sadb_supported *sup;
	u_int len, alen, elen;
	int off;
	int i;
	struct sadb_alg *alg;

	/* create new sadb_msg to reply. */
	alen = 0;
	for (i = 1; i <= SADB_AALG_MAX; i++) {
		if (auth_algorithm_lookup(i))