/* $OpenBSD: rtp.c,v 1.3 2015/10/21 03:48:09 renato Exp $ */ /* * Copyright (c) 2015 Renato Westphal * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include "eigrpd.h" #include "eigrp.h" #include "eigrpe.h" #include "rde.h" #include "log.h" void rtp_retrans_timer(int, short, void *); void rtp_retrans_start_timer(struct packet *); void rtp_retrans_stop_timer(struct packet *); struct pbuf * rtp_buf_new(struct ibuf *buf) { struct pbuf *pbuf; if ((pbuf = calloc(1, sizeof(*pbuf))) == NULL) fatal("rtp_buf_new"); pbuf->buf = buf; return (pbuf); } struct pbuf * rtp_buf_hold(struct pbuf *pbuf) { pbuf->refcnt++; return (pbuf); } void rtp_buf_release(struct pbuf *pbuf) { if (--pbuf->refcnt == 0) { ibuf_free(pbuf->buf); free(pbuf); } } struct packet * rtp_packet_new(struct nbr *nbr, uint32_t seq_num, struct pbuf *pbuf) { struct packet *pkt; if ((pkt = calloc(1, sizeof(struct packet))) == NULL) fatal("rtp_packet_new"); pkt->nbr = nbr; pkt->seq_num = seq_num; pkt->pbuf = rtp_buf_hold(pbuf); pkt->attempts = 1; evtimer_set(&pkt->ev_timeout, rtp_retrans_timer, pkt); return (pkt); } void rtp_packet_del(struct packet *pkt) { TAILQ_REMOVE(&pkt->nbr->retrans_list, pkt, entry); rtp_retrans_stop_timer(pkt); rtp_buf_release(pkt->pbuf); free(pkt); } void rtp_process_ack(struct nbr *nbr, uint32_t ack_num) { struct eigrp *eigrp = nbr->ei->eigrp; struct packet *pkt; /* window size is one */ pkt = TAILQ_FIRST(&nbr->retrans_list); if (pkt && pkt->seq_num == ack_num) { log_debug("%s: nbr %s ack %u", __func__, log_addr(eigrp->af, &nbr->addr), ack_num); /* dequeue packet from retransmission queue */ rtp_packet_del(pkt); /* enqueue next packet from retransmission queue */ pkt = TAILQ_FIRST(&nbr->retrans_list); if (pkt) rtp_send_packet(pkt); } } void rtp_send_packet(struct packet *pkt) { rtp_retrans_start_timer(pkt); send_packet(pkt->nbr->ei, pkt->nbr, 0, pkt->pbuf->buf); } void rtp_enqueue_packet(struct packet *pkt) { /* only send packet if transmission queue is empty */ if (TAILQ_EMPTY(&pkt->nbr->retrans_list)) rtp_send_packet(pkt); TAILQ_INSERT_TAIL(&pkt->nbr->retrans_list, pkt, entry); } static void rtp_seq_inc(struct eigrp *eigrp) { /* automatic wraparound with unsigned arithmetic */ eigrp->seq_num++; /* sequence number 0 is reserved for unreliably transmission */ if (eigrp->seq_num == 0) eigrp->seq_num = 1; } void rtp_send_ucast(struct nbr *nbr, struct ibuf *buf) { struct eigrp *eigrp = nbr->ei->eigrp; struct packet *pkt; struct pbuf *pbuf; pbuf = rtp_buf_new(buf); pkt = rtp_packet_new(nbr, eigrp->seq_num, pbuf); rtp_enqueue_packet(pkt); rtp_seq_inc(eigrp); } void rtp_send_mcast(struct eigrp_iface *ei, struct ibuf *buf) { struct eigrp *eigrp = ei->eigrp; struct nbr *nbr; int total = 0, pending = 0; struct packet *pkt; struct pbuf *pbuf; uint32_t flags = 0; struct seq_addr_entry *sa; struct seq_addr_head seq_addr_list; TAILQ_FOREACH(nbr, &ei->nbr_list, entry) { if (nbr->flags & F_EIGRP_NBR_SELF) continue; if (!TAILQ_EMPTY(&nbr->retrans_list)) pending++; total++; } if (total == 0) return; /* * send a multicast if there's at least one neighbor with an empty * queue on the interface. */ if (pending < total) { /* * build a hello packet with a seq tlv indicating all the * neighbors that have full queues. */ if (pending > 0) { flags |= EIGRP_HDR_FLAG_CR; TAILQ_INIT(&seq_addr_list); TAILQ_FOREACH(nbr, &ei->nbr_list, entry) { if (TAILQ_EMPTY(&nbr->retrans_list)) continue; if ((sa = calloc(1, sizeof(*sa))) == NULL) fatal("rtp_send_mcast"); sa->af = eigrp->af; memcpy(&sa->addr, &nbr->addr, sizeof(sa->addr)); TAILQ_INSERT_TAIL(&seq_addr_list, sa, entry); } send_hello(ei, &seq_addr_list, eigrp->seq_num, 0); seq_addr_list_clr(&seq_addr_list); } send_packet(ei, NULL, flags, buf); } /* schedule an unicast retransmission for each neighbor */ pbuf = rtp_buf_new(buf); TAILQ_FOREACH(nbr, &ei->nbr_list, entry) { pkt = rtp_packet_new(nbr, eigrp->seq_num, pbuf); TAILQ_INSERT_TAIL(&nbr->retrans_list, pkt, entry); } rtp_seq_inc(eigrp); } void rtp_send(struct eigrp_iface *ei, struct nbr *nbr, struct ibuf *buf) { if (nbr) rtp_send_ucast(nbr, buf); else rtp_send_mcast(ei, buf); } void rtp_send_ack(struct nbr *nbr) { struct eigrp *eigrp = nbr->ei->eigrp; struct ibuf *buf; if ((buf = ibuf_dynamic(PKG_DEF_SIZE, IP_MAXPACKET - sizeof(struct ip))) == NULL) fatal("rtp_send_ack"); /* EIGRP header */ if (gen_eigrp_hdr(buf, EIGRP_OPC_HELLO, 0, 0, eigrp->as)) { log_warnx("%s: failed to send message", __func__); ibuf_free(buf); return; } /* send unreliably */ send_packet(nbr->ei, nbr, 0, buf); ibuf_free(buf); } /* timers */ /* ARGSUSED */ void rtp_retrans_timer(int fd, short event, void *arg) { struct packet *pkt = arg; struct eigrp *eigrp = pkt->nbr->ei->eigrp; pkt->attempts++; if (pkt->attempts > RTP_RTRNS_MAX_ATTEMPTS) { log_warnx("%s: retry limit exceeded, nbr %s", __func__, log_addr(eigrp->af, &pkt->nbr->addr)); nbr_del(pkt->nbr); return; } rtp_send_packet(pkt); } void rtp_retrans_start_timer(struct packet *pkt) { struct timeval tv; timerclear(&tv); tv.tv_sec = RTP_RTRNS_INTERVAL; if (evtimer_add(&pkt->ev_timeout, &tv) == -1) fatal("rtp_retrans_start_timer"); } void rtp_retrans_stop_timer(struct packet *pkt) { if (evtimer_pending(&pkt->ev_timeout, NULL) && evtimer_del(&pkt->ev_timeout) == -1) fatal("rtp_retrans_stop_timer"); } /* ARGSUSED */ void rtp_ack_timer(int fd, short event, void *arg) { struct nbr *nbr = arg; rtp_send_ack(nbr); } void rtp_ack_start_timer(struct nbr *nbr) { struct timeval tv; timerclear(&tv); tv.tv_usec = RTP_ACK_TIMEOUT; if (evtimer_add(&nbr->ev_ack, &tv) == -1) fatal("rtp_ack_start_timer"); } void rtp_ack_stop_timer(struct nbr *nbr) { if (evtimer_pending(&nbr->ev_ack, NULL) && evtimer_del(&nbr->ev_ack) == -1) fatal("rtp_ack_stop_timer"); }