Function sctp_send_shutdown_ack

freebsd/netinet/sctp_output.c:9134–9175

}

void
sctp_send_shutdown_ack(struct sctp_tcb *stcb, struct sctp_nets *net)
{
	/* formulate and queue a SHUTDOWN-ACK back to the sender */
	struct mbuf *m_shutdown_ack;
	struct sctp_shutdown_ack_chunk *ack_cp;
	struct sctp_tmit_chunk *chk;

	m_shutdown_ack = sctp_get_mbuf_for_msg(sizeof(struct sctp_shutdown_ack_chunk), 0, M_NOWAIT, 1, MT_HEADER);
	if (m_shutdown_ack == NULL) {
		/* no mbuf's */
		return;
	}
	SCTP_BUF_RESV_UF(m_shutdown_ack, SCTP_MIN_OVERHEAD);
	sctp_alloc_a_chunk(stcb, chk);
	if (chk == NULL) {
		/* no memory */
		sctp_m_freem(m_shutdown_ack);
		return;
	}
	chk->copy_by_ref = 0;
	chk->rec.chunk_id.id = SCTP_SHUTDOWN_ACK;
	chk->rec.chunk_id.can_take_data = 1;
	chk->flags = 0;
	chk->send_size = sizeof(struct sctp_chunkhdr);
	chk->sent = SCTP_DATAGRAM_UNSENT;
	chk->snd_count = 0;
	chk->asoc = &stcb->asoc;
	chk->data = m_shutdown_ack;
	chk->whoTo = net;
	if (chk->whoTo) {
		atomic_add_int(&chk->whoTo->ref_count, 1);
	}
	ack_cp = mtod(m_shutdown_ack, struct sctp_shutdown_ack_chunk *);
	ack_cp->ch.chunk_type = SCTP_SHUTDOWN_ACK;
	ack_cp->ch.chunk_flags = 0;
	ack_cp->ch.chunk_length = htons(chk->send_size);
	SCTP_BUF_LEN(m_shutdown_ack) = chk->send_size;
	TAILQ_INSERT_TAIL(&chk->asoc->control_send_queue, chk, sctp_next);
	chk->asoc->ctrl_queue_cnt++;
	return;
}

void
sctp_send_shutdown(struct sctp_tcb *stcb, struct sctp_nets *net)