Function key_spdacquire

freebsd/netipsec/key.c:2424–2470

* SADB_X_SPDACQUIRE processing. * Acquire policy and SA(s) for a *OUTBOUND* packet. * send * * to KMD, and expect to receive * with SADB_X_SPDACQUIRE if error occurred, * or * * with SADB_X_SPDUPDATE from KMD by PF_KEY. * policy(*) is without policy requests. * * 0 : succeed * others: error number */

 *    others: error number
 */
int
key_spdacquire(struct secpolicy *sp)
{
	struct mbuf *result = NULL, *m;
	struct secspacq *newspacq;

	IPSEC_ASSERT(sp != NULL, ("null secpolicy"));
	IPSEC_ASSERT(sp->req == NULL, ("policy exists"));
	IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
		("policy not IPSEC %u", sp->policy));

	/* Get an entry to check whether sent message or not. */
	newspacq = key_getspacq(&sp->spidx);
	if (newspacq != NULL) {
		if (V_key_blockacq_count < newspacq->count) {
			/* reset counter and do send message. */
			newspacq->count = 0;
		} else {
			/* increment counter and do nothing. */
			newspacq->count++;
			SPACQ_UNLOCK();
			return (0);
		}
		SPACQ_UNLOCK();
	} else {
		/* make new entry for blocking to send SADB_ACQUIRE. */
		newspacq = key_newspacq(&sp->spidx);
		if (newspacq == NULL)
			return ENOBUFS;
	}

	/* create new sadb_msg to reply. */
	m = key_setsadbmsg(SADB_X_SPDACQUIRE, 0, 0, 0, 0, 0);
	if (!m)
		return ENOBUFS;

	result = m;

	result->m_pkthdr.len = 0;
	for (m = result; m; m = m->m_next)
		result->m_pkthdr.len += m->m_len;

	mtod(result, struct sadb_msg *)->sadb_msg_len =
	    PFKEY_UNIT64(result->m_pkthdr.len);

	return key_sendup_mbuf(NULL, m, KEY_SENDUP_REGISTERED);
}

/*
 * SADB_SPDFLUSH processing