[thirdparty/bird.git] / proto / ospf / dbdes.c

/*
 *	BIRD -- OSPF
 *
 *	(c) 1999--2004 Ondrej Filip <feela@network.cz>
 *	(c) 2009--2014 Ondrej Zajicek <santiago@crfreenet.org>
 *	(c) 2009--2014 CZ.NIC z.s.p.o.
 *
 *	Can be freely distributed and used under the terms of the GNU GPL.
 */

#include "ospf.h"


struct ospf_dbdes2_packet
{
  struct ospf_packet hdr;
  union ospf_auth2 auth;

  u16 iface_mtu;
  u8 options;
  u8 imms;			/* I, M, MS bits */
  u32 ddseq;

  struct ospf_lsa_header lsas[];
};

struct ospf_dbdes3_packet
{
  struct ospf_packet hdr;

  u32 options;
  u16 iface_mtu;
  u8 padding;
  u8 imms;			/* I, M, MS bits */
  u32 ddseq;

  struct ospf_lsa_header lsas[];
};


uint
ospf_dbdes3_options(struct ospf_packet *pkt)
{
  struct ospf_dbdes3_packet *ps = (void *) pkt;
  return ntohl(ps->options);
}

static inline uint
ospf_dbdes_hdrlen(struct ospf_proto *p)
{
  return ospf_is_v2(p) ?
    sizeof(struct ospf_dbdes2_packet) : sizeof(struct ospf_dbdes3_packet);
}

static void
ospf_dbdes_body(struct ospf_proto *p, struct ospf_packet *pkt,
		struct ospf_lsa_header **body, uint *count)
{
  uint plen = ntohs(pkt->length);
  uint hlen = ospf_dbdes_hdrlen(p);

  *body = ((void *) pkt) + hlen;
  *count = (plen - hlen) / sizeof(struct ospf_lsa_header);
}

static void
ospf_dump_dbdes(struct ospf_proto *p, struct ospf_packet *pkt)
{
  struct ospf_lsa_header *lsas;
  uint i, lsa_count;
  u32 pkt_ddseq;
  u16 pkt_iface_mtu;
  u8 pkt_imms;

  ASSERT(pkt->type == DBDES_P);
  ospf_dump_common(p, pkt);

  if (ospf_is_v2(p))
  {
    struct ospf_dbdes2_packet *ps = (void *) pkt;
    pkt_iface_mtu = ntohs(ps->iface_mtu);
    pkt_imms = ps->imms;
    pkt_ddseq = ntohl(ps->ddseq);
  }
  else /* OSPFv3 */
  {
    struct ospf_dbdes3_packet *ps = (void *) pkt;
    pkt_iface_mtu = ntohs(ps->iface_mtu);
    pkt_imms = ps->imms;
    pkt_ddseq = ntohl(ps->ddseq);
  }

  log(L_TRACE "%s:     mtu      %u", p->p.name, pkt_iface_mtu);
  log(L_TRACE "%s:     imms     %s%s%s", p->p.name,
      (pkt_imms & DBDES_I) ? "I " : "",
      (pkt_imms & DBDES_M) ? "M " : "",
      (pkt_imms & DBDES_MS) ? "MS" : "");
  log(L_TRACE "%s:     ddseq    %u", p->p.name, pkt_ddseq);

  ospf_dbdes_body(p, pkt, &lsas, &lsa_count);
  for (i = 0; i < lsa_count; i++)
    ospf_dump_lsahdr(p, lsas + i);
}


static void
ospf_prepare_dbdes(struct ospf_proto *p, struct ospf_neighbor *n)
{
  struct ospf_iface *ifa = n->ifa;
  struct ospf_packet *pkt;
  uint length;

  u16 iface_mtu = (ifa->type == OSPF_IT_VLINK) ? 0 : ifa->iface->mtu;

  /* Update DBDES buffer */
  if (n->ldd_bsize != ifa->tx_length)
  {
    mb_free(n->ldd_buffer);
    n->ldd_buffer = mb_allocz(n->pool, ifa->tx_length);
    n->ldd_bsize = ifa->tx_length;
  }

  pkt = n->ldd_buffer;
  ospf_pkt_fill_hdr(ifa, pkt, DBDES_P);

  if (ospf_is_v2(p))
  {
    struct ospf_dbdes2_packet *ps = (void *) pkt;
    ps->iface_mtu = htons(iface_mtu);
    ps->options = ifa->oa->options & DBDES2_OPT_MASK;
    ps->imms = 0;	/* Will be set later */
    ps->ddseq = htonl(n->dds);
    length = sizeof(struct ospf_dbdes2_packet);
  }
  else /* OSPFv3 */
  {
    struct ospf_dbdes3_packet *ps = (void *) pkt;
    u32 options = ifa->oa->options | (ifa->autype == OSPF_AUTH_CRYPT ? OPT_AT : 0);
    ps->options = htonl(options & DBDES3_OPT_MASK);
    ps->iface_mtu = htons(iface_mtu);
    ps->padding = 0;
    ps->imms = 0;	/* Will be set later */
    ps->ddseq = htonl(n->dds);
    length = sizeof(struct ospf_dbdes3_packet);
  }

  /* Prepare DBDES body */
  if (!(n->myimms & DBDES_I) && (n->myimms & DBDES_M))
  {
    struct ospf_lsa_header *lsas;
    struct top_hash_entry *en;
    uint i = 0, lsa_max;

    ospf_dbdes_body(p, pkt, &lsas, &lsa_max);
    en = (void *) s_get(&(n->dbsi));

    while (i < lsa_max)
    {
      if (!SNODE_VALID(en))
      {
	n->myimms &= ~DBDES_M;	/* Unset More bit */
	break;
      }

      if ((en->lsa.age < LSA_MAXAGE) &&
	  lsa_flooding_allowed(en->lsa_type, en->domain, ifa) &&
	  lsa_is_acceptable(en->lsa_type, n, p))
      {
	lsa_hton_hdr(&(en->lsa), lsas + i);
	i++;
      }

      en = SNODE_NEXT(en);
    }

    s_put(&(n->dbsi), SNODE en);

    length += i * sizeof(struct ospf_lsa_header);
  }

  if (ospf_is_v2(p))
    ((struct ospf_dbdes2_packet *) pkt)->imms = n->myimms;
  else
    ((struct ospf_dbdes3_packet *) pkt)->imms = n->myimms;

  pkt->length = htons(length);
}

static void
ospf_do_send_dbdes(struct ospf_proto *p, struct ospf_neighbor *n)
{
  struct ospf_iface *ifa = n->ifa;

  OSPF_PACKET(ospf_dump_dbdes, n->ldd_buffer,
	      "DBDES packet sent to nbr %R on %s", n->rid, ifa->ifname);
  sk_set_tbuf(ifa->sk, n->ldd_buffer);
  ospf_send_to(ifa, n->ip);
  sk_set_tbuf(ifa->sk, NULL);
}

/**
 * ospf_send_dbdes - transmit database description packet
 * @p: OSPF protocol instance
 * @n: neighbor
 *
 * Sending of a database description packet is described in 10.8 of RFC 2328.
 * Reception of each packet is acknowledged in the sequence number of another.
 * When I send a packet to a neighbor I keep a copy in a buffer. If the neighbor
 * does not reply, I don't create a new packet but just send the content
 * of the buffer.
 */
void
ospf_send_dbdes(struct ospf_proto *p, struct ospf_neighbor *n)
{
  /* RFC 2328 10.8 */

  ASSERT((n->state == NEIGHBOR_EXSTART) || (n->state == NEIGHBOR_EXCHANGE));

  if (!n->ifa->oa->rt && !p->gr_recovery)
    return;

  ospf_prepare_dbdes(p, n);
  ospf_do_send_dbdes(p, n);
}

void
ospf_rxmt_dbdes(struct ospf_proto *p, struct ospf_neighbor *n)
{
  ASSERT(n->state > NEIGHBOR_EXSTART);

  if (!n->ldd_buffer)
  {
    log(L_WARN "%s: No DBDES packet for retransmit", p->p.name);
    ospf_neigh_sm(n, INM_SEQMIS);
    return;
  }

  /* Send last packet */
  ospf_do_send_dbdes(p, n);
}

void
ospf_reset_ldd(struct ospf_proto *p UNUSED, struct ospf_neighbor *n)
{
  mb_free(n->ldd_buffer);
  n->ldd_buffer = NULL;
  n->ldd_bsize = 0;
}

static int
ospf_process_dbdes(struct ospf_proto *p, struct ospf_packet *pkt, struct ospf_neighbor *n)
{
  struct ospf_iface *ifa = n->ifa;
  struct ospf_lsa_header *lsas, lsa;
  struct top_hash_entry *en, *req;
  const char *err_dsc = NULL;
  u32 lsa_type, lsa_domain;
  uint i, lsa_count;

  ospf_dbdes_body(p, pkt, &lsas, &lsa_count);

  for (i = 0; i < lsa_count; i++)
  {
    lsa_ntoh_hdr(lsas + i, &lsa);
    lsa_get_type_domain(&lsa, ifa, &lsa_type, &lsa_domain);

    /* RFC 2328 10.6 and RFC 5340 4.2.2 */

    if (!lsa_type)
      DROP1("LSA of unknown type");

    if (!oa_is_ext(ifa->oa) && (LSA_SCOPE(lsa_type) == LSA_SCOPE_AS))
      DROP1("LSA with AS scope in stub area");

    /* Errata 3746 to RFC 2328 - rt-summary-LSAs forbidden in stub areas */
    if (!oa_is_ext(ifa->oa) && (lsa_type == LSA_T_SUM_RT))
      DROP1("rt-summary-LSA in stub area");

    /* Not explicitly mentioned in RFC 5340 4.2.2 but makes sense */
    if (LSA_SCOPE(lsa_type) == LSA_SCOPE_RES)
      DROP1("LSA with invalid scope");

    /* RFC 3623 2.2 (2) special case - check for my router-LSA (GR recovery) */
    if ((lsa_type == LSA_T_RT) && (lsa.rt == p->router_id))
      n->got_my_rt_lsa = 1;

    en = ospf_hash_find(p->gr, lsa_domain, lsa.id, lsa.rt, lsa_type);
    if (!en || (lsa_comp(&lsa, &(en->lsa)) == CMP_NEWER))
    {
      /* This should be splitted to ospf_lsa_lsrq_up() */
      req = ospf_hash_get(n->lsrqh, lsa_domain, lsa.id, lsa.rt, lsa_type);

      if (!SNODE_VALID(req))
	s_add_tail(&n->lsrql, SNODE req);

      if (!SNODE_VALID(n->lsrqi))
	n->lsrqi = req;

      req->lsa = lsa;
      req->lsa_body = LSA_BODY_DUMMY;

      if (!tm_active(n->lsrq_timer))
	tm_start(n->lsrq_timer, 0);
    }
  }

  return 0;

drop:
  LOG_LSA1("Bad LSA (Type: %04x, Id: %R, Rt: %R) in DBDES", lsa_type, lsa.id, lsa.rt);
  LOG_LSA2("  received from nbr %R on %s - %s", n->rid, ifa->ifname, err_dsc);

  ospf_neigh_sm(n, INM_SEQMIS);
  return -1;
}

void
ospf_receive_dbdes(struct ospf_packet *pkt, struct ospf_iface *ifa,
		   struct ospf_neighbor *n)
{
  struct ospf_proto *p = ifa->oa->po;
  const char *err_dsc = NULL;
  u32 rcv_ddseq, rcv_options;
  u16 rcv_iface_mtu;
  u8 rcv_imms;
  uint plen, err_val = 0;

  /* RFC 2328 10.6 */

  plen = ntohs(pkt->length);
  if (plen < ospf_dbdes_hdrlen(p))
  {
    LOG_PKT("Bad DBDES packet from nbr %R on %s - %s (%u)", n->rid, ifa->ifname, "too short", plen);
    return;
  }

  OSPF_PACKET(ospf_dump_dbdes, pkt, "DBDES packet received from nbr %R on %s", n->rid, ifa->ifname);

  ospf_neigh_sm(n, INM_HELLOREC);

  if (ospf_is_v2(p))
  {
    struct ospf_dbdes2_packet *ps = (void *) pkt;
    rcv_iface_mtu = ntohs(ps->iface_mtu);
    rcv_options = ps->options;
    rcv_imms = ps->imms;
    rcv_ddseq = ntohl(ps->ddseq);
  }
  else /* OSPFv3 */
  {
    struct ospf_dbdes3_packet *ps = (void *) pkt;
    rcv_options = ntohl(ps->options);
    rcv_iface_mtu = ntohs(ps->iface_mtu);
    rcv_imms = ps->imms;
    rcv_ddseq = ntohl(ps->ddseq);
  }

  /* Reject packets with non-matching MTU */
  if ((ifa->type != OSPF_IT_VLINK) &&
      (rcv_iface_mtu != ifa->iface->mtu) &&
      (rcv_iface_mtu != 0) && (ifa->iface->mtu != 0))
  {
    LOG_PKT("MTU mismatch with nbr %R on %s (remote %d, local %d)",
	    n->rid, ifa->ifname, rcv_iface_mtu, ifa->iface->mtu);
    return;
  }

  switch (n->state)
  {
  case NEIGHBOR_DOWN:
  case NEIGHBOR_ATTEMPT:
  case NEIGHBOR_2WAY:
    OSPF_TRACE(D_PACKETS, "DBDES packet ignored - lesser state than ExStart");
    return;

  case NEIGHBOR_INIT:
    ospf_neigh_sm(n, INM_2WAYREC);
    if (n->state != NEIGHBOR_EXSTART)
      return;
    /* fallthrough */

  case NEIGHBOR_EXSTART:
    if (((rcv_imms & DBDES_IMMS) == DBDES_IMMS) &&
	(n->rid > p->router_id) &&
	(plen == ospf_dbdes_hdrlen(p)))
    {
      /* I'm slave! */
      n->dds = rcv_ddseq;
      n->ddr = rcv_ddseq;
      n->options = rcv_options;
      n->myimms &= ~DBDES_MS;
      n->imms = rcv_imms;
      tm_stop(n->dbdes_timer);
      ospf_neigh_sm(n, INM_NEGDONE);
      ospf_send_dbdes(p, n);
      break;
    }

    if (!(rcv_imms & DBDES_I) &&
	!(rcv_imms & DBDES_MS) &&
	(n->rid < p->router_id) &&
	(n->dds == rcv_ddseq))
    {
      /* I'm master! */
      n->options = rcv_options;
      n->ddr = rcv_ddseq - 1;	/* It will be set corectly a few lines down */
      n->imms = rcv_imms;
      ospf_neigh_sm(n, INM_NEGDONE);
      /* Continue to the NEIGHBOR_EXCHANGE case */
    }
    else
    {
      DBG("%s: Nothing happend to %I (imms=%d)\n", p->name, n->ip, rcv_imms);
      break;
    }

  case NEIGHBOR_EXCHANGE:
    if ((rcv_imms == n->imms) &&
	(rcv_options == n->options) &&
	(rcv_ddseq == n->ddr))
      goto duplicate;

    if ((rcv_imms & DBDES_MS) != (n->imms & DBDES_MS))
      DROP("MS-bit mismatch", rcv_imms);

    if (rcv_imms & DBDES_I)
      DROP("I-bit mismatch", rcv_imms);

    if (rcv_options != n->options)
      DROP("options mismatch", rcv_options);

    n->ddr = rcv_ddseq;
    n->imms = rcv_imms;

    if (n->myimms & DBDES_MS)
    {
      /* MASTER */

      if (rcv_ddseq != n->dds)
	DROP("DD sequence number mismatch", rcv_ddseq);

      n->dds++;

      if (ospf_process_dbdes(p, pkt, n) < 0)
	return;

      if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
      {
	tm_stop(n->dbdes_timer);
	ospf_reset_ldd(p, n);
	ospf_neigh_sm(n, INM_EXDONE);
	break;
      }

      ospf_send_dbdes(p, n);
      tm_start(n->dbdes_timer, n->ifa->rxmtint S);
    }
    else
    {
      /* SLAVE */

      if (rcv_ddseq != (n->dds + 1))
	DROP("DD sequence number mismatch", rcv_ddseq);

      n->ddr = rcv_ddseq;
      n->dds = rcv_ddseq;

      if (ospf_process_dbdes(p, pkt, n) < 0)
	return;

      ospf_send_dbdes(p, n);

      if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
      {
	/* Use dbdes timer to postpone freeing of Last DBDES packet buffer */
	tm_start(n->dbdes_timer, n->ifa->deadint S);
	ospf_neigh_sm(n, INM_EXDONE);
      }
    }
    break;

  case NEIGHBOR_LOADING:
  case NEIGHBOR_FULL:
    if ((rcv_imms == n->imms) &&
	(rcv_options == n->options) &&
	(rcv_ddseq == n->ddr))
      goto duplicate;

    DROP("too late for DD exchange", n->state);

  default:
    bug("Undefined interface state");
  }
  return;

duplicate:
  OSPF_TRACE(D_PACKETS, "DBDES packet is duplicate");

  /* Slave should retransmit DBDES packet */
  if (!(n->myimms & DBDES_MS))
    ospf_rxmt_dbdes(p, n);
  return;

drop:
  LOG_PKT("Bad DBDES packet from nbr %R on %s - %s (%u)",
	  n->rid, ifa->ifname, err_dsc, err_val);

  ospf_neigh_sm(n, INM_SEQMIS);
  return;
}
Commit	Line	Data
4364b47e OF	1	/*
	2	* BIRD -- OSPF
	3	*
f158bb71	4	* (c) 1999--2004 Ondrej Filip <feela@network.cz>
70945cb6 OZ	5	* (c) 2009--2014 Ondrej Zajicek <santiago@crfreenet.org>
70945cb6 OZ	6	* (c) 2009--2014 CZ.NIC z.s.p.o.
4364b47e OF	7	*
	8	* Can be freely distributed and used under the terms of the GNU GPL.
	9	*/
	10
	11	#include "ospf.h"
	12
c3226991	13
70945cb6	14	struct ospf_dbdes2_packet
c3226991	15	{
70945cb6	16	struct ospf_packet hdr;
4727d1db	17	union ospf_auth2 auth;
70945cb6	18
c3226991 OZ	19	u16 iface_mtu;
c3226991 OZ	20	u8 options;
70945cb6	21	u8 imms; /* I, M, MS bits */
c3226991	22	u32 ddseq;
c3226991	23
70945cb6 OZ	24	struct ospf_lsa_header lsas[];
70945cb6 OZ	25	};
c3226991	26
70945cb6	27	struct ospf_dbdes3_packet
c3226991	28	{
70945cb6 OZ	29	struct ospf_packet hdr;
70945cb6 OZ	30
c3226991 OZ	31	u32 options;
	32	u16 iface_mtu;
	33	u8 padding;
70945cb6	34	u8 imms; /* I, M, MS bits */
c3226991	35	u32 ddseq;
70945cb6 OZ	36
70945cb6 OZ	37	struct ospf_lsa_header lsas[];
c3226991 OZ	38	};
c3226991 OZ	39
c3226991	40
4727d1db OZ	41	uint
	42	ospf_dbdes3_options(struct ospf_packet *pkt)
	43	{
	44	struct ospf_dbdes3_packet ps = (void ) pkt;
	45	return ntohl(ps->options);
	46	}
	47
70945cb6 OZ	48	static inline uint
	49	ospf_dbdes_hdrlen(struct ospf_proto *p)
	50	{
	51	return ospf_is_v2(p) ?
	52	sizeof(struct ospf_dbdes2_packet) : sizeof(struct ospf_dbdes3_packet);
	53	}
	54
70945cb6 OZ	55	static void
	56	ospf_dbdes_body(struct ospf_proto p, struct ospf_packet pkt,
	57	struct ospf_lsa_header *body, uint count)
	58	{
	59	uint plen = ntohs(pkt->length);
	60	uint hlen = ospf_dbdes_hdrlen(p);
	61
	62	body = ((void ) pkt) + hlen;
	63	*count = (plen - hlen) / sizeof(struct ospf_lsa_header);
	64	}
742029eb	65
70945cb6 OZ	66	static void
70945cb6 OZ	67	ospf_dump_dbdes(struct ospf_proto p, struct ospf_packet pkt)
8298d780	68	{
70945cb6 OZ	69	struct ospf_lsa_header *lsas;
	70	uint i, lsa_count;
	71	u32 pkt_ddseq;
	72	u16 pkt_iface_mtu;
	73	u8 pkt_imms;
8298d780	74
70945cb6 OZ	75	ASSERT(pkt->type == DBDES_P);
70945cb6 OZ	76	ospf_dump_common(p, pkt);
8298d780	77
70945cb6 OZ	78	if (ospf_is_v2(p))
	79	{
	80	struct ospf_dbdes2_packet ps = (void ) pkt;
	81	pkt_iface_mtu = ntohs(ps->iface_mtu);
	82	pkt_imms = ps->imms;
	83	pkt_ddseq = ntohl(ps->ddseq);
	84	}
	85	else /* OSPFv3 */
	86	{
	87	struct ospf_dbdes3_packet ps = (void ) pkt;
	88	pkt_iface_mtu = ntohs(ps->iface_mtu);
	89	pkt_imms = ps->imms;
	90	pkt_ddseq = ntohl(ps->ddseq);
	91	}
8298d780	92
70945cb6 OZ	93	log(L_TRACE "%s: mtu %u", p->p.name, pkt_iface_mtu);
	94	log(L_TRACE "%s: imms %s%s%s", p->p.name,
	95	(pkt_imms & DBDES_I) ? "I " : "",
	96	(pkt_imms & DBDES_M) ? "M " : "",
	97	(pkt_imms & DBDES_MS) ? "MS" : "");
	98	log(L_TRACE "%s: ddseq %u", p->p.name, pkt_ddseq);
8298d780	99
70945cb6 OZ	100	ospf_dbdes_body(p, pkt, &lsas, &lsa_count);
	101	for (i = 0; i < lsa_count; i++)
	102	ospf_dump_lsahdr(p, lsas + i);
8298d780 OZ	103	}
	104
	105
70945cb6	106	static void
f8fefde3	107	ospf_prepare_dbdes(struct ospf_proto p, struct ospf_neighbor n)
70945cb6 OZ	108	{
	109	struct ospf_iface *ifa = n->ifa;
	110	struct ospf_packet *pkt;
	111	uint length;
	112
	113	u16 iface_mtu = (ifa->type == OSPF_IT_VLINK) ? 0 : ifa->iface->mtu;
	114
f8fefde3	115	/* Update DBDES buffer */
70945cb6 OZ	116	if (n->ldd_bsize != ifa->tx_length)
	117	{
	118	mb_free(n->ldd_buffer);
	119	n->ldd_buffer = mb_allocz(n->pool, ifa->tx_length);
	120	n->ldd_bsize = ifa->tx_length;
	121	}
	122
	123	pkt = n->ldd_buffer;
	124	ospf_pkt_fill_hdr(ifa, pkt, DBDES_P);
	125
	126	if (ospf_is_v2(p))
	127	{
	128	struct ospf_dbdes2_packet ps = (void ) pkt;
	129	ps->iface_mtu = htons(iface_mtu);
1aec7112	130	ps->options = ifa->oa->options & DBDES2_OPT_MASK;
70945cb6 OZ	131	ps->imms = 0; /* Will be set later */
	132	ps->ddseq = htonl(n->dds);
	133	length = sizeof(struct ospf_dbdes2_packet);
	134	}
	135	else /* OSPFv3 */
	136	{
	137	struct ospf_dbdes3_packet ps = (void ) pkt;
1aec7112 OZ	138	u32 options = ifa->oa->options \| (ifa->autype == OSPF_AUTH_CRYPT ? OPT_AT : 0);
1aec7112 OZ	139	ps->options = htonl(options & DBDES3_OPT_MASK);
70945cb6 OZ	140	ps->iface_mtu = htons(iface_mtu);
	141	ps->padding = 0;
	142	ps->imms = 0; /* Will be set later */
	143	ps->ddseq = htonl(n->dds);
	144	length = sizeof(struct ospf_dbdes3_packet);
	145	}
	146
f8fefde3 OZ	147	/* Prepare DBDES body */
f8fefde3 OZ	148	if (!(n->myimms & DBDES_I) && (n->myimms & DBDES_M))
70945cb6 OZ	149	{
	150	struct ospf_lsa_header *lsas;
	151	struct top_hash_entry *en;
	152	uint i = 0, lsa_max;
	153
	154	ospf_dbdes_body(p, pkt, &lsas, &lsa_max);
	155	en = (void *) s_get(&(n->dbsi));
	156
	157	while (i < lsa_max)
	158	{
	159	if (!SNODE_VALID(en))
	160	{
	161	n->myimms &= ~DBDES_M; /* Unset More bit */
	162	break;
	163	}
	164
	165	if ((en->lsa.age < LSA_MAXAGE) &&
5a50a989 OZ	166	lsa_flooding_allowed(en->lsa_type, en->domain, ifa) &&
5a50a989 OZ	167	lsa_is_acceptable(en->lsa_type, n, p))
70945cb6 OZ	168	{
	169	lsa_hton_hdr(&(en->lsa), lsas + i);
	170	i++;
	171	}
	172
	173	en = SNODE_NEXT(en);
	174	}
	175
	176	s_put(&(n->dbsi), SNODE en);
	177
	178	length += i * sizeof(struct ospf_lsa_header);
	179	}
	180
	181	if (ospf_is_v2(p))
	182	((struct ospf_dbdes2_packet *) pkt)->imms = n->myimms;
	183	else
	184	((struct ospf_dbdes3_packet *) pkt)->imms = n->myimms;
	185
	186	pkt->length = htons(length);
	187	}
	188
	189	static void
	190	ospf_do_send_dbdes(struct ospf_proto p, struct ospf_neighbor n)
	191	{
	192	struct ospf_iface *ifa = n->ifa;
	193
	194	OSPF_PACKET(ospf_dump_dbdes, n->ldd_buffer,
f8fefde3	195	"DBDES packet sent to nbr %R on %s", n->rid, ifa->ifname);
70945cb6 OZ	196	sk_set_tbuf(ifa->sk, n->ldd_buffer);
	197	ospf_send_to(ifa, n->ip);
	198	sk_set_tbuf(ifa->sk, NULL);
	199	}
	200
eee9cefd	201	/**
70945cb6	202	* ospf_send_dbdes - transmit database description packet
8e433d6a	203	* @p: OSPF protocol instance
eee9cefd OF	204	* @n: neighbor
eee9cefd OF	205	*
c3226991	206	* Sending of a database description packet is described in 10.8 of RFC 2328.
baa5dd6c OF	207	* Reception of each packet is acknowledged in the sequence number of another.
	208	* When I send a packet to a neighbor I keep a copy in a buffer. If the neighbor
	209	* does not reply, I don't create a new packet but just send the content
	210	* of the buffer.
eee9cefd	211	*/
4364b47e	212	void
f8fefde3	213	ospf_send_dbdes(struct ospf_proto p, struct ospf_neighbor n)
4364b47e	214	{
70945cb6	215	/* RFC 2328 10.8 */
4364b47e	216
f8fefde3 OZ	217	ASSERT((n->state == NEIGHBOR_EXSTART) \|\| (n->state == NEIGHBOR_EXCHANGE));
f8fefde3 OZ	218
1a2ad348	219	if (!n->ifa->oa->rt && !p->gr_recovery)
70945cb6	220	return;
054a3524	221
f8fefde3 OZ	222	ospf_prepare_dbdes(p, n);
f8fefde3 OZ	223	ospf_do_send_dbdes(p, n);
f8fefde3	224	}
12bed559	225
f8fefde3 OZ	226	void
	227	ospf_rxmt_dbdes(struct ospf_proto p, struct ospf_neighbor n)
	228	{
	229	ASSERT(n->state > NEIGHBOR_EXSTART);
e7ef86a5	230
f8fefde3 OZ	231	if (!n->ldd_buffer)
	232	{
	233	log(L_WARN "%s: No DBDES packet for retransmit", p->p.name);
	234	ospf_neigh_sm(n, INM_SEQMIS);
	235	return;
70945cb6	236	}
04c6319a	237
f8fefde3 OZ	238	/* Send last packet */
	239	ospf_do_send_dbdes(p, n);
	240	}
48e5f32d	241
16605f2f OZ	242	void
	243	ospf_reset_ldd(struct ospf_proto p UNUSED, struct ospf_neighbor n)
	244	{
	245	mb_free(n->ldd_buffer);
	246	n->ldd_buffer = NULL;
	247	n->ldd_bsize = 0;
	248	}
	249
70945cb6 OZ	250	static int
	251	ospf_process_dbdes(struct ospf_proto p, struct ospf_packet pkt, struct ospf_neighbor *n)
	252	{
	253	struct ospf_iface *ifa = n->ifa;
f8fefde3 OZ	254	struct ospf_lsa_header *lsas, lsa;
	255	struct top_hash_entry en, req;
	256	const char *err_dsc = NULL;
	257	u32 lsa_type, lsa_domain;
70945cb6 OZ	258	uint i, lsa_count;
	259
	260	ospf_dbdes_body(p, pkt, &lsas, &lsa_count);
	261
	262	for (i = 0; i < lsa_count; i++)
	263	{
70945cb6 OZ	264	lsa_ntoh_hdr(lsas + i, &lsa);
70945cb6 OZ	265	lsa_get_type_domain(&lsa, ifa, &lsa_type, &lsa_domain);
b1f7229a	266
70945cb6	267	/* RFC 2328 10.6 and RFC 5340 4.2.2 */
b1f7229a	268
70945cb6	269	if (!lsa_type)
f8fefde3	270	DROP1("LSA of unknown type");
4364b47e	271
70945cb6	272	if (!oa_is_ext(ifa->oa) && (LSA_SCOPE(lsa_type) == LSA_SCOPE_AS))
f8fefde3	273	DROP1("LSA with AS scope in stub area");
4364b47e	274
70945cb6 OZ	275	/* Errata 3746 to RFC 2328 - rt-summary-LSAs forbidden in stub areas */
70945cb6 OZ	276	if (!oa_is_ext(ifa->oa) && (lsa_type == LSA_T_SUM_RT))
f8fefde3	277	DROP1("rt-summary-LSA in stub area");
910e557b	278
70945cb6 OZ	279	/* Not explicitly mentioned in RFC 5340 4.2.2 but makes sense */
70945cb6 OZ	280	if (LSA_SCOPE(lsa_type) == LSA_SCOPE_RES)
f8fefde3	281	DROP1("LSA with invalid scope");
910e557b	282
1a2ad348 OZ	283	/* RFC 3623 2.2 (2) special case - check for my router-LSA (GR recovery) */
	284	if ((lsa_type == LSA_T_RT) && (lsa.rt == p->router_id))
	285	n->got_my_rt_lsa = 1;
	286
70945cb6 OZ	287	en = ospf_hash_find(p->gr, lsa_domain, lsa.id, lsa.rt, lsa_type);
	288	if (!en \|\| (lsa_comp(&lsa, &(en->lsa)) == CMP_NEWER))
	289	{
6f8bbaa1	290	/* This should be splitted to ospf_lsa_lsrq_up() */
70945cb6	291	req = ospf_hash_get(n->lsrqh, lsa_domain, lsa.id, lsa.rt, lsa_type);
6d2b3211	292
70945cb6 OZ	293	if (!SNODE_VALID(req))
70945cb6 OZ	294	s_add_tail(&n->lsrql, SNODE req);
6d2b3211	295
6f8bbaa1 OZ	296	if (!SNODE_VALID(n->lsrqi))
	297	n->lsrqi = req;
	298
70945cb6	299	req->lsa = lsa;
a7a7372a	300	req->lsa_body = LSA_BODY_DUMMY;
6f8bbaa1	301
a6f79ca5 OZ	302	if (!tm_active(n->lsrq_timer))
a6f79ca5 OZ	303	tm_start(n->lsrq_timer, 0);
95eb1dba	304	}
6d2b3211	305	}
70945cb6 OZ	306
	307	return 0;
	308
f8fefde3 OZ	309	drop:
	310	LOG_LSA1("Bad LSA (Type: %04x, Id: %R, Rt: %R) in DBDES", lsa_type, lsa.id, lsa.rt);
	311	LOG_LSA2(" received from nbr %R on %s - %s", n->rid, ifa->ifname, err_dsc);
	312
70945cb6 OZ	313	ospf_neigh_sm(n, INM_SEQMIS);
70945cb6 OZ	314	return -1;
4364b47e OF	315	}
	316
	317	void
70945cb6	318	ospf_receive_dbdes(struct ospf_packet pkt, struct ospf_iface ifa,
c3226991	319	struct ospf_neighbor *n)
4364b47e	320	{
70945cb6	321	struct ospf_proto *p = ifa->oa->po;
f8fefde3	322	const char *err_dsc = NULL;
70945cb6 OZ	323	u32 rcv_ddseq, rcv_options;
	324	u16 rcv_iface_mtu;
	325	u8 rcv_imms;
6f8bbaa1	326	uint plen, err_val = 0;
4364b47e	327
70945cb6 OZ	328	/* RFC 2328 10.6 */
	329
	330	plen = ntohs(pkt->length);
	331	if (plen < ospf_dbdes_hdrlen(p))
6f8bbaa1 OZ	332	{
	333	LOG_PKT("Bad DBDES packet from nbr %R on %s - %s (%u)", n->rid, ifa->ifname, "too short", plen);
	334	return;
	335	}
a6bc04d5	336
f8fefde3	337	OSPF_PACKET(ospf_dump_dbdes, pkt, "DBDES packet received from nbr %R on %s", n->rid, ifa->ifname);
b1f7229a	338
4bb9ce56	339	ospf_neigh_sm(n, INM_HELLOREC);
353f3261	340
70945cb6 OZ	341	if (ospf_is_v2(p))
	342	{
	343	struct ospf_dbdes2_packet ps = (void ) pkt;
	344	rcv_iface_mtu = ntohs(ps->iface_mtu);
	345	rcv_options = ps->options;
	346	rcv_imms = ps->imms;
	347	rcv_ddseq = ntohl(ps->ddseq);
	348	}
	349	else /* OSPFv3 */
	350	{
	351	struct ospf_dbdes3_packet ps = (void ) pkt;
	352	rcv_options = ntohl(ps->options);
	353	rcv_iface_mtu = ntohs(ps->iface_mtu);
	354	rcv_imms = ps->imms;
	355	rcv_ddseq = ntohl(ps->ddseq);
	356	}
742029eb	357
267da813 OZ	358	/* Reject packets with non-matching MTU */
	359	if ((ifa->type != OSPF_IT_VLINK) &&
	360	(rcv_iface_mtu != ifa->iface->mtu) &&
	361	(rcv_iface_mtu != 0) && (ifa->iface->mtu != 0))
	362	{
	363	LOG_PKT("MTU mismatch with nbr %R on %s (remote %d, local %d)",
	364	n->rid, ifa->ifname, rcv_iface_mtu, ifa->iface->mtu);
	365	return;
	366	}
	367
12bed559	368	switch (n->state)
4364b47e	369	{
12bed559 OF	370	case NEIGHBOR_DOWN:
	371	case NEIGHBOR_ATTEMPT:
	372	case NEIGHBOR_2WAY:
f8fefde3	373	OSPF_TRACE(D_PACKETS, "DBDES packet ignored - lesser state than ExStart");
12bed559	374	return;
70945cb6	375
12bed559 OF	376	case NEIGHBOR_INIT:
	377	ospf_neigh_sm(n, INM_2WAYREC);
	378	if (n->state != NEIGHBOR_EXSTART)
	379	return;
d4cebc6b	380	/* fallthrough */
9f1500f5	381
70945cb6	382	case NEIGHBOR_EXSTART:
d3f4f92b	383	if (((rcv_imms & DBDES_IMMS) == DBDES_IMMS) &&
70945cb6 OZ	384	(n->rid > p->router_id) &&
70945cb6 OZ	385	(plen == ospf_dbdes_hdrlen(p)))
12bed559 OF	386	{
12bed559 OF	387	/* I'm slave! */
70945cb6 OZ	388	n->dds = rcv_ddseq;
	389	n->ddr = rcv_ddseq;
	390	n->options = rcv_options;
	391	n->myimms &= ~DBDES_MS;
	392	n->imms = rcv_imms;
a6f79ca5	393	tm_stop(n->dbdes_timer);
12bed559	394	ospf_neigh_sm(n, INM_NEGDONE);
f8fefde3	395	ospf_send_dbdes(p, n);
4364b47e	396	break;
12bed559	397	}
b1f7229a	398
70945cb6 OZ	399	if (!(rcv_imms & DBDES_I) &&
70945cb6 OZ	400	!(rcv_imms & DBDES_MS) &&
742029eb	401	(n->rid < p->router_id) &&
70945cb6	402	(n->dds == rcv_ddseq))
12bed559	403	{
b1f7229a	404	/* I'm master! */
70945cb6 OZ	405	n->options = rcv_options;
	406	n->ddr = rcv_ddseq - 1; /* It will be set corectly a few lines down */
	407	n->imms = rcv_imms;
b1f7229a	408	ospf_neigh_sm(n, INM_NEGDONE);
6f8bbaa1	409	/* Continue to the NEIGHBOR_EXCHANGE case */
12bed559	410	}
b1f7229a OF	411	else
b1f7229a OF	412	{
70945cb6	413	DBG("%s: Nothing happend to %I (imms=%d)\n", p->name, n->ip, rcv_imms);
12bed559	414	break;
b1f7229a	415	}
70945cb6	416
12bed559	417	case NEIGHBOR_EXCHANGE:
70945cb6 OZ	418	if ((rcv_imms == n->imms) &&
	419	(rcv_options == n->options) &&
	420	(rcv_ddseq == n->ddr))
f8fefde3	421	goto duplicate;
910e557b	422
f8fefde3 OZ	423	if ((rcv_imms & DBDES_MS) != (n->imms & DBDES_MS))
f8fefde3 OZ	424	DROP("MS-bit mismatch", rcv_imms);
12bed559	425
f8fefde3 OZ	426	if (rcv_imms & DBDES_I)
	427	DROP("I-bit mismatch", rcv_imms);
	428
	429	if (rcv_options != n->options)
	430	DROP("options mismatch", rcv_options);
4364b47e	431
70945cb6 OZ	432	n->ddr = rcv_ddseq;
	433	n->imms = rcv_imms;
	434
	435	if (n->myimms & DBDES_MS)
12bed559	436	{
f8fefde3 OZ	437	/* MASTER */
	438
	439	if (rcv_ddseq != n->dds)
	440	DROP("DD sequence number mismatch", rcv_ddseq);
70945cb6	441
12bed559	442	n->dds++;
70945cb6 OZ	443
	444	if (ospf_process_dbdes(p, pkt, n) < 0)
	445	return;
	446
	447	if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
6f8bbaa1	448	{
a6f79ca5	449	tm_stop(n->dbdes_timer);
16605f2f	450	ospf_reset_ldd(p, n);
12bed559	451	ospf_neigh_sm(n, INM_EXDONE);
6f8bbaa1 OZ	452	break;
	453	}
	454
	455	ospf_send_dbdes(p, n);
a6f79ca5	456	tm_start(n->dbdes_timer, n->ifa->rxmtint S);
12bed559 OF	457	}
	458	else
	459	{
f8fefde3 OZ	460	/* SLAVE */
	461
	462	if (rcv_ddseq != (n->dds + 1))
	463	DROP("DD sequence number mismatch", rcv_ddseq);
12bed559	464
70945cb6 OZ	465	n->ddr = rcv_ddseq;
	466	n->dds = rcv_ddseq;
	467
	468	if (ospf_process_dbdes(p, pkt, n) < 0)
	469	return;
	470
f8fefde3	471	ospf_send_dbdes(p, n);
6f8bbaa1 OZ	472
6f8bbaa1 OZ	473	if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
16605f2f OZ	474	{
	475	/* Use dbdes timer to postpone freeing of Last DBDES packet buffer */
	476	tm_start(n->dbdes_timer, n->ifa->deadint S);
6f8bbaa1	477	ospf_neigh_sm(n, INM_EXDONE);
16605f2f	478	}
70945cb6	479	}
12bed559	480	break;
70945cb6	481
12bed559 OF	482	case NEIGHBOR_LOADING:
12bed559 OF	483	case NEIGHBOR_FULL:
70945cb6 OZ	484	if ((rcv_imms == n->imms) &&
	485	(rcv_options == n->options) &&
	486	(rcv_ddseq == n->ddr))
f8fefde3 OZ	487	goto duplicate;
f8fefde3 OZ	488
f8fefde3	489	DROP("too late for DD exchange", n->state);
70945cb6	490
189dab54	491	default:
f8fefde3	492	bug("Undefined interface state");
12bed559	493	}
f8fefde3 OZ	494	return;
	495
	496	duplicate:
	497	OSPF_TRACE(D_PACKETS, "DBDES packet is duplicate");
	498
	499	/* Slave should retransmit DBDES packet */
	500	if (!(n->myimms & DBDES_MS))
	501	ospf_rxmt_dbdes(p, n);
	502	return;
	503
	504	drop:
	505	LOG_PKT("Bad DBDES packet from nbr %R on %s - %s (%u)",
	506	n->rid, ifa->ifname, err_dsc, err_val);
	507
6f8bbaa1	508	ospf_neigh_sm(n, INM_SEQMIS);
f8fefde3	509	return;
12bed559	510	}