[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_auth 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[];
};


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;
    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;
    ps->options = htonl(ifa->oa->options);
    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_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
 * @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 == NULL)
    return;

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

  if (n->state == NEIGHBOR_EXSTART)
    return;

  /* Master should restart RXMT timer for each DBDES exchange */
  if (n->myimms & DBDES_MS)
    tm_start(n->rxmt_timer, n->ifa->rxmtint);

  if (!(n->myimms & DBDES_MS))
    if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
      ospf_neigh_sm(n, INM_EXDONE);
}

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);
}

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");

    en = ospf_hash_find(p->gr, lsa_domain, lsa.id, lsa.rt, lsa_type);
    if (!en || (lsa_comp(&lsa, &(en->lsa)) == CMP_NEWER))
    {
      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);

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

  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, err_seqmis = 0;

  /* RFC 2328 10.6 */

  plen = ntohs(pkt->length);
  if (plen < ospf_dbdes_hdrlen(p))
    DROP("too short", plen);

  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);
  }

  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;

  case NEIGHBOR_EXSTART:
    if ((ifa->type != OSPF_IT_VLINK) &&
	(rcv_iface_mtu != ifa->iface->mtu) &&
	(rcv_iface_mtu != 0) &&
	(ifa->iface->mtu != 0))
      LOG_PKT_WARN("MTU mismatch with nbr %R on %s (remote %d, local %d)",
		   n->rid, ifa->ifname, rcv_iface_mtu, ifa->iface->mtu);

    if ((rcv_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;
      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);
    }
    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;

    /* Do INM_SEQMIS during packet error */
    err_seqmis = 1;

    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))
	ospf_neigh_sm(n, INM_EXDONE);
      else
	ospf_send_dbdes(p, n);
    }
    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);
    }
    break;

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

    err_seqmis = 1;

    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);

  if (err_seqmis)
    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 OZ	16	struct ospf_packet hdr;
	17	union ospf_auth auth;
	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
70945cb6 OZ	41	static inline uint
	42	ospf_dbdes_hdrlen(struct ospf_proto *p)
	43	{
	44	return ospf_is_v2(p) ?
	45	sizeof(struct ospf_dbdes2_packet) : sizeof(struct ospf_dbdes3_packet);
	46	}
	47
	48
	49	static void
	50	ospf_dbdes_body(struct ospf_proto p, struct ospf_packet pkt,
	51	struct ospf_lsa_header *body, uint count)
	52	{
	53	uint plen = ntohs(pkt->length);
	54	uint hlen = ospf_dbdes_hdrlen(p);
	55
	56	body = ((void ) pkt) + hlen;
	57	*count = (plen - hlen) / sizeof(struct ospf_lsa_header);
	58	}
742029eb	59
70945cb6 OZ	60	static void
70945cb6 OZ	61	ospf_dump_dbdes(struct ospf_proto p, struct ospf_packet pkt)
8298d780	62	{
70945cb6 OZ	63	struct ospf_lsa_header *lsas;
	64	uint i, lsa_count;
	65	u32 pkt_ddseq;
	66	u16 pkt_iface_mtu;
	67	u8 pkt_imms;
8298d780	68
70945cb6 OZ	69	ASSERT(pkt->type == DBDES_P);
70945cb6 OZ	70	ospf_dump_common(p, pkt);
8298d780	71
70945cb6 OZ	72	if (ospf_is_v2(p))
	73	{
	74	struct ospf_dbdes2_packet ps = (void ) pkt;
	75	pkt_iface_mtu = ntohs(ps->iface_mtu);
	76	pkt_imms = ps->imms;
	77	pkt_ddseq = ntohl(ps->ddseq);
	78	}
	79	else /* OSPFv3 */
	80	{
	81	struct ospf_dbdes3_packet ps = (void ) pkt;
	82	pkt_iface_mtu = ntohs(ps->iface_mtu);
	83	pkt_imms = ps->imms;
	84	pkt_ddseq = ntohl(ps->ddseq);
	85	}
8298d780	86
70945cb6 OZ	87	log(L_TRACE "%s: mtu %u", p->p.name, pkt_iface_mtu);
	88	log(L_TRACE "%s: imms %s%s%s", p->p.name,
	89	(pkt_imms & DBDES_I) ? "I " : "",
	90	(pkt_imms & DBDES_M) ? "M " : "",
	91	(pkt_imms & DBDES_MS) ? "MS" : "");
	92	log(L_TRACE "%s: ddseq %u", p->p.name, pkt_ddseq);
8298d780	93
70945cb6 OZ	94	ospf_dbdes_body(p, pkt, &lsas, &lsa_count);
	95	for (i = 0; i < lsa_count; i++)
	96	ospf_dump_lsahdr(p, lsas + i);
8298d780 OZ	97	}
	98
	99
70945cb6	100	static void
f8fefde3	101	ospf_prepare_dbdes(struct ospf_proto p, struct ospf_neighbor n)
70945cb6 OZ	102	{
	103	struct ospf_iface *ifa = n->ifa;
	104	struct ospf_packet *pkt;
	105	uint length;
	106
	107	u16 iface_mtu = (ifa->type == OSPF_IT_VLINK) ? 0 : ifa->iface->mtu;
	108
f8fefde3	109	/* Update DBDES buffer */
70945cb6 OZ	110	if (n->ldd_bsize != ifa->tx_length)
	111	{
	112	mb_free(n->ldd_buffer);
	113	n->ldd_buffer = mb_allocz(n->pool, ifa->tx_length);
	114	n->ldd_bsize = ifa->tx_length;
	115	}
	116
	117	pkt = n->ldd_buffer;
	118	ospf_pkt_fill_hdr(ifa, pkt, DBDES_P);
	119
	120	if (ospf_is_v2(p))
	121	{
	122	struct ospf_dbdes2_packet ps = (void ) pkt;
	123	ps->iface_mtu = htons(iface_mtu);
	124	ps->options = ifa->oa->options;
	125	ps->imms = 0; /* Will be set later */
	126	ps->ddseq = htonl(n->dds);
	127	length = sizeof(struct ospf_dbdes2_packet);
	128	}
	129	else /* OSPFv3 */
	130	{
	131	struct ospf_dbdes3_packet ps = (void ) pkt;
	132	ps->options = htonl(ifa->oa->options);
	133	ps->iface_mtu = htons(iface_mtu);
	134	ps->padding = 0;
	135	ps->imms = 0; /* Will be set later */
	136	ps->ddseq = htonl(n->dds);
	137	length = sizeof(struct ospf_dbdes3_packet);
	138	}
	139
f8fefde3 OZ	140	/* Prepare DBDES body */
f8fefde3 OZ	141	if (!(n->myimms & DBDES_I) && (n->myimms & DBDES_M))
70945cb6 OZ	142	{
	143	struct ospf_lsa_header *lsas;
	144	struct top_hash_entry *en;
	145	uint i = 0, lsa_max;
	146
	147	ospf_dbdes_body(p, pkt, &lsas, &lsa_max);
	148	en = (void *) s_get(&(n->dbsi));
	149
	150	while (i < lsa_max)
	151	{
	152	if (!SNODE_VALID(en))
	153	{
	154	n->myimms &= ~DBDES_M; /* Unset More bit */
	155	break;
	156	}
	157
	158	if ((en->lsa.age < LSA_MAXAGE) &&
	159	lsa_flooding_allowed(en->lsa_type, en->domain, ifa))
	160	{
	161	lsa_hton_hdr(&(en->lsa), lsas + i);
	162	i++;
	163	}
	164
	165	en = SNODE_NEXT(en);
	166	}
	167
	168	s_put(&(n->dbsi), SNODE en);
	169
	170	length += i * sizeof(struct ospf_lsa_header);
	171	}
	172
	173	if (ospf_is_v2(p))
	174	((struct ospf_dbdes2_packet *) pkt)->imms = n->myimms;
	175	else
	176	((struct ospf_dbdes3_packet *) pkt)->imms = n->myimms;
	177
	178	pkt->length = htons(length);
	179	}
	180
	181	static void
	182	ospf_do_send_dbdes(struct ospf_proto p, struct ospf_neighbor n)
	183	{
	184	struct ospf_iface *ifa = n->ifa;
	185
	186	OSPF_PACKET(ospf_dump_dbdes, n->ldd_buffer,
f8fefde3	187	"DBDES packet sent to nbr %R on %s", n->rid, ifa->ifname);
70945cb6 OZ	188	sk_set_tbuf(ifa->sk, n->ldd_buffer);
	189	ospf_send_to(ifa, n->ip);
	190	sk_set_tbuf(ifa->sk, NULL);
	191	}
	192
eee9cefd	193	/**
70945cb6	194	* ospf_send_dbdes - transmit database description packet
eee9cefd OF	195	* @n: neighbor
eee9cefd OF	196	*
c3226991	197	* Sending of a database description packet is described in 10.8 of RFC 2328.
baa5dd6c OF	198	* Reception of each packet is acknowledged in the sequence number of another.
	199	* When I send a packet to a neighbor I keep a copy in a buffer. If the neighbor
	200	* does not reply, I don't create a new packet but just send the content
	201	* of the buffer.
eee9cefd	202	*/
4364b47e	203	void
f8fefde3	204	ospf_send_dbdes(struct ospf_proto p, struct ospf_neighbor n)
4364b47e	205	{
70945cb6	206	/* RFC 2328 10.8 */
4364b47e	207
f8fefde3 OZ	208	ASSERT((n->state == NEIGHBOR_EXSTART) \|\| (n->state == NEIGHBOR_EXCHANGE));
f8fefde3 OZ	209
a7a7372a	210	if (n->ifa->oa->rt == NULL)
70945cb6	211	return;
054a3524	212
f8fefde3 OZ	213	ospf_prepare_dbdes(p, n);
f8fefde3 OZ	214	ospf_do_send_dbdes(p, n);
30147b89	215
f8fefde3 OZ	216	if (n->state == NEIGHBOR_EXSTART)
f8fefde3 OZ	217	return;
781aa475	218
f8fefde3 OZ	219	/* Master should restart RXMT timer for each DBDES exchange */
	220	if (n->myimms & DBDES_MS)
	221	tm_start(n->rxmt_timer, n->ifa->rxmtint);
12bed559	222
f8fefde3 OZ	223	if (!(n->myimms & DBDES_MS))
	224	if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
	225	ospf_neigh_sm(n, INM_EXDONE);
	226	}
12bed559	227
f8fefde3 OZ	228	void
	229	ospf_rxmt_dbdes(struct ospf_proto p, struct ospf_neighbor n)
	230	{
	231	ASSERT(n->state > NEIGHBOR_EXSTART);
e7ef86a5	232
f8fefde3 OZ	233	if (!n->ldd_buffer)
	234	{
	235	log(L_WARN "%s: No DBDES packet for retransmit", p->p.name);
	236	ospf_neigh_sm(n, INM_SEQMIS);
	237	return;
70945cb6	238	}
04c6319a	239
f8fefde3 OZ	240	/* Send last packet */
	241	ospf_do_send_dbdes(p, n);
	242	}
48e5f32d	243
70945cb6 OZ	244	static int
	245	ospf_process_dbdes(struct ospf_proto p, struct ospf_packet pkt, struct ospf_neighbor *n)
	246	{
	247	struct ospf_iface *ifa = n->ifa;
f8fefde3 OZ	248	struct ospf_lsa_header *lsas, lsa;
	249	struct top_hash_entry en, req;
	250	const char *err_dsc = NULL;
	251	u32 lsa_type, lsa_domain;
70945cb6 OZ	252	uint i, lsa_count;
	253
	254	ospf_dbdes_body(p, pkt, &lsas, &lsa_count);
	255
	256	for (i = 0; i < lsa_count; i++)
	257	{
70945cb6 OZ	258	lsa_ntoh_hdr(lsas + i, &lsa);
70945cb6 OZ	259	lsa_get_type_domain(&lsa, ifa, &lsa_type, &lsa_domain);
b1f7229a	260
70945cb6	261	/* RFC 2328 10.6 and RFC 5340 4.2.2 */
b1f7229a	262
70945cb6	263	if (!lsa_type)
f8fefde3	264	DROP1("LSA of unknown type");
4364b47e	265
70945cb6	266	if (!oa_is_ext(ifa->oa) && (LSA_SCOPE(lsa_type) == LSA_SCOPE_AS))
f8fefde3	267	DROP1("LSA with AS scope in stub area");
4364b47e	268
70945cb6 OZ	269	/* Errata 3746 to RFC 2328 - rt-summary-LSAs forbidden in stub areas */
70945cb6 OZ	270	if (!oa_is_ext(ifa->oa) && (lsa_type == LSA_T_SUM_RT))
f8fefde3	271	DROP1("rt-summary-LSA in stub area");
910e557b	272
70945cb6 OZ	273	/* Not explicitly mentioned in RFC 5340 4.2.2 but makes sense */
70945cb6 OZ	274	if (LSA_SCOPE(lsa_type) == LSA_SCOPE_RES)
f8fefde3	275	DROP1("LSA with invalid scope");
910e557b	276
70945cb6 OZ	277	en = ospf_hash_find(p->gr, lsa_domain, lsa.id, lsa.rt, lsa_type);
	278	if (!en \|\| (lsa_comp(&lsa, &(en->lsa)) == CMP_NEWER))
	279	{
	280	req = ospf_hash_get(n->lsrqh, lsa_domain, lsa.id, lsa.rt, lsa_type);
6d2b3211	281
70945cb6 OZ	282	if (!SNODE_VALID(req))
70945cb6 OZ	283	s_add_tail(&n->lsrql, SNODE req);
6d2b3211	284
70945cb6	285	req->lsa = lsa;
a7a7372a	286	req->lsa_body = LSA_BODY_DUMMY;
95eb1dba	287	}
6d2b3211	288	}
70945cb6 OZ	289
	290	return 0;
	291
f8fefde3 OZ	292	drop:
	293	LOG_LSA1("Bad LSA (Type: %04x, Id: %R, Rt: %R) in DBDES", lsa_type, lsa.id, lsa.rt);
	294	LOG_LSA2(" received from nbr %R on %s - %s", n->rid, ifa->ifname, err_dsc);
	295
70945cb6 OZ	296	ospf_neigh_sm(n, INM_SEQMIS);
70945cb6 OZ	297	return -1;
4364b47e OF	298	}
	299
	300	void
70945cb6	301	ospf_receive_dbdes(struct ospf_packet pkt, struct ospf_iface ifa,
c3226991	302	struct ospf_neighbor *n)
4364b47e	303	{
70945cb6	304	struct ospf_proto *p = ifa->oa->po;
f8fefde3	305	const char *err_dsc = NULL;
70945cb6 OZ	306	u32 rcv_ddseq, rcv_options;
	307	u16 rcv_iface_mtu;
	308	u8 rcv_imms;
f8fefde3	309	uint plen, err_val = 0, err_seqmis = 0;
4364b47e	310
70945cb6 OZ	311	/* RFC 2328 10.6 */
	312
	313	plen = ntohs(pkt->length);
	314	if (plen < ospf_dbdes_hdrlen(p))
f8fefde3	315	DROP("too short", plen);
a6bc04d5	316
f8fefde3	317	OSPF_PACKET(ospf_dump_dbdes, pkt, "DBDES packet received from nbr %R on %s", n->rid, ifa->ifname);
b1f7229a	318
4bb9ce56	319	ospf_neigh_sm(n, INM_HELLOREC);
353f3261	320
70945cb6 OZ	321	if (ospf_is_v2(p))
	322	{
	323	struct ospf_dbdes2_packet ps = (void ) pkt;
	324	rcv_iface_mtu = ntohs(ps->iface_mtu);
	325	rcv_options = ps->options;
	326	rcv_imms = ps->imms;
	327	rcv_ddseq = ntohl(ps->ddseq);
	328	}
	329	else /* OSPFv3 */
	330	{
	331	struct ospf_dbdes3_packet ps = (void ) pkt;
	332	rcv_options = ntohl(ps->options);
	333	rcv_iface_mtu = ntohs(ps->iface_mtu);
	334	rcv_imms = ps->imms;
	335	rcv_ddseq = ntohl(ps->ddseq);
	336	}
742029eb	337
12bed559	338	switch (n->state)
4364b47e	339	{
12bed559 OF	340	case NEIGHBOR_DOWN:
	341	case NEIGHBOR_ATTEMPT:
	342	case NEIGHBOR_2WAY:
f8fefde3	343	OSPF_TRACE(D_PACKETS, "DBDES packet ignored - lesser state than ExStart");
12bed559	344	return;
70945cb6	345
12bed559 OF	346	case NEIGHBOR_INIT:
	347	ospf_neigh_sm(n, INM_2WAYREC);
	348	if (n->state != NEIGHBOR_EXSTART)
	349	return;
9f1500f5	350
70945cb6 OZ	351	case NEIGHBOR_EXSTART:
	352	if ((ifa->type != OSPF_IT_VLINK) &&
	353	(rcv_iface_mtu != ifa->iface->mtu) &&
	354	(rcv_iface_mtu != 0) &&
	355	(ifa->iface->mtu != 0))
f8fefde3 OZ	356	LOG_PKT_WARN("MTU mismatch with nbr %R on %s (remote %d, local %d)",
f8fefde3 OZ	357	n->rid, ifa->ifname, rcv_iface_mtu, ifa->iface->mtu);
70945cb6 OZ	358
	359	if ((rcv_imms == DBDES_IMMS) &&
	360	(n->rid > p->router_id) &&
	361	(plen == ospf_dbdes_hdrlen(p)))
12bed559 OF	362	{
12bed559 OF	363	/* I'm slave! */
70945cb6 OZ	364	n->dds = rcv_ddseq;
	365	n->ddr = rcv_ddseq;
	366	n->options = rcv_options;
	367	n->myimms &= ~DBDES_MS;
	368	n->imms = rcv_imms;
12bed559	369	ospf_neigh_sm(n, INM_NEGDONE);
f8fefde3	370	ospf_send_dbdes(p, n);
4364b47e	371	break;
12bed559	372	}
b1f7229a	373
70945cb6 OZ	374	if (!(rcv_imms & DBDES_I) &&
70945cb6 OZ	375	!(rcv_imms & DBDES_MS) &&
742029eb	376	(n->rid < p->router_id) &&
70945cb6	377	(n->dds == rcv_ddseq))
12bed559	378	{
b1f7229a	379	/* I'm master! */
70945cb6 OZ	380	n->options = rcv_options;
	381	n->ddr = rcv_ddseq - 1; /* It will be set corectly a few lines down */
	382	n->imms = rcv_imms;
b1f7229a	383	ospf_neigh_sm(n, INM_NEGDONE);
12bed559	384	}
b1f7229a OF	385	else
b1f7229a OF	386	{
70945cb6	387	DBG("%s: Nothing happend to %I (imms=%d)\n", p->name, n->ip, rcv_imms);
12bed559	388	break;
b1f7229a	389	}
70945cb6	390
12bed559	391	case NEIGHBOR_EXCHANGE:
70945cb6 OZ	392	if ((rcv_imms == n->imms) &&
	393	(rcv_options == n->options) &&
	394	(rcv_ddseq == n->ddr))
f8fefde3	395	goto duplicate;
910e557b	396
f8fefde3 OZ	397	/* Do INM_SEQMIS during packet error */
f8fefde3 OZ	398	err_seqmis = 1;
12bed559	399
f8fefde3 OZ	400	if ((rcv_imms & DBDES_MS) != (n->imms & DBDES_MS))
f8fefde3 OZ	401	DROP("MS-bit mismatch", rcv_imms);
12bed559	402
f8fefde3 OZ	403	if (rcv_imms & DBDES_I)
	404	DROP("I-bit mismatch", rcv_imms);
	405
	406	if (rcv_options != n->options)
	407	DROP("options mismatch", rcv_options);
4364b47e	408
70945cb6 OZ	409	n->ddr = rcv_ddseq;
	410	n->imms = rcv_imms;
	411
	412	if (n->myimms & DBDES_MS)
12bed559	413	{
f8fefde3 OZ	414	/* MASTER */
	415
	416	if (rcv_ddseq != n->dds)
	417	DROP("DD sequence number mismatch", rcv_ddseq);
70945cb6	418
12bed559	419	n->dds++;
70945cb6 OZ	420
	421	if (ospf_process_dbdes(p, pkt, n) < 0)
	422	return;
	423
	424	if (!(n->myimms & DBDES_M) && !(n->imms & DBDES_M))
12bed559	425	ospf_neigh_sm(n, INM_EXDONE);
12bed559	426	else
f8fefde3	427	ospf_send_dbdes(p, n);
12bed559 OF	428	}
	429	else
	430	{
f8fefde3 OZ	431	/* SLAVE */
	432
	433	if (rcv_ddseq != (n->dds + 1))
	434	DROP("DD sequence number mismatch", rcv_ddseq);
12bed559	435
70945cb6 OZ	436	n->ddr = rcv_ddseq;
	437	n->dds = rcv_ddseq;
	438
	439	if (ospf_process_dbdes(p, pkt, n) < 0)
	440	return;
	441
f8fefde3	442	ospf_send_dbdes(p, n);
70945cb6	443	}
12bed559	444	break;
70945cb6	445
12bed559 OF	446	case NEIGHBOR_LOADING:
12bed559 OF	447	case NEIGHBOR_FULL:
70945cb6 OZ	448	if ((rcv_imms == n->imms) &&
	449	(rcv_options == n->options) &&
	450	(rcv_ddseq == n->ddr))
f8fefde3 OZ	451	goto duplicate;
	452
	453	err_seqmis = 1;
	454
	455	DROP("too late for DD exchange", n->state);
70945cb6	456
189dab54	457	default:
f8fefde3	458	bug("Undefined interface state");
12bed559	459	}
f8fefde3 OZ	460	return;
	461
	462	duplicate:
	463	OSPF_TRACE(D_PACKETS, "DBDES packet is duplicate");
	464
	465	/* Slave should retransmit DBDES packet */
	466	if (!(n->myimms & DBDES_MS))
	467	ospf_rxmt_dbdes(p, n);
	468	return;
	469
	470	drop:
	471	LOG_PKT("Bad DBDES packet from nbr %R on %s - %s (%u)",
	472	n->rid, ifa->ifname, err_dsc, err_val);
	473
	474	if (err_seqmis)
	475	ospf_neigh_sm(n, INM_SEQMIS);
	476	return;
12bed559	477	}