void
ospf_if_set_multicast(struct ospf_interface *oi)
{
if ((oi->state > ISM_Loopback) &&
(oi->type != OSPF_IFTYPE_LOOPBACK) &&
(oi->type != OSPF_IFTYPE_VIRTUALLINK) &&
(OSPF_IF_PASSIVE_STATUS(oi) == OSPF_IF_ACTIVE))
{
/* The interface should belong to the OSPF-all-routers group. */
if (!OI_MEMBER_CHECK(oi, MEMBER_ALLROUTERS) &&
(ospf_if_add_allspfrouters(oi->ospf, oi->address,
oi->ifp->ifindex) >= 0))
/* Set the flag only if the system call to join succeeded. */
OI_MEMBER_JOINED(oi, MEMBER_ALLROUTERS);
}
else
{
/* The interface should NOT belong to the OSPF-all-routers group. */
if (OI_MEMBER_CHECK(oi, MEMBER_ALLROUTERS))
{
/* Only actually drop if this is the last reference */
if (OI_MEMBER_COUNT(oi, MEMBER_ALLROUTERS) == 1)
ospf_if_drop_allspfrouters (oi->ospf, oi->address,
oi->ifp->ifindex);
/* Unset the flag regardless of whether the system call to leave
the group succeeded, since it's much safer to assume that
we are not a member. */
OI_MEMBER_LEFT(oi,MEMBER_ALLROUTERS);
}
}
if (((oi->type == OSPF_IFTYPE_BROADCAST) ||
(oi->type == OSPF_IFTYPE_POINTOPOINT)) &&
((oi->state == ISM_DR) || (oi->state == ISM_Backup)) &&
(OSPF_IF_PASSIVE_STATUS(oi) == OSPF_IF_ACTIVE))
{
/* The interface should belong to the OSPF-designated-routers group. */
if (!OI_MEMBER_CHECK(oi, MEMBER_DROUTERS) &&
(ospf_if_add_alldrouters(oi->ospf, oi->address,
oi->ifp->ifindex) >= 0))
/* Set the flag only if the system call to join succeeded. */
OI_MEMBER_JOINED(oi, MEMBER_DROUTERS);
}
else
{
/* The interface should NOT belong to the OSPF-designated-routers group */
if (OI_MEMBER_CHECK(oi, MEMBER_DROUTERS))
{
/* drop only if last reference */
if (OI_MEMBER_COUNT(oi, MEMBER_DROUTERS) == 1)
ospf_if_drop_alldrouters(oi->ospf, oi->address, oi->ifp->ifindex);
/* Unset the flag regardless of whether the system call to leave
the group succeeded, since it's much safer to assume that
we are not a member. */
OI_MEMBER_LEFT(oi, MEMBER_DROUTERS);
}
}
}
int
ospf_dr_election (struct ospf_interface *oi)
{
struct in_addr old_dr, old_bdr;
int old_state, new_state;
struct list *el_list;
struct ospf_neighbor *dr, *bdr;
/* backup current values. */
old_dr = DR (oi);
old_bdr = BDR (oi);
old_state = oi->state;
el_list = list_new ();
/* List eligible routers. */
ospf_dr_eligible_routers (oi->nbrs, el_list);
/* First election of DR and BDR. */
bdr = ospf_elect_bdr (oi, el_list);
dr = ospf_elect_dr (oi, el_list);
new_state = ospf_ism_state (oi);
zlog_info ("DR-Election[1st]: Backup %s", inet_ntoa (BDR (oi)));
zlog_info ("DR-Election[1st]: DR %s", inet_ntoa (DR (oi)));
if (new_state != old_state &&
!(new_state == ISM_DROther && old_state < ISM_DROther))
{
ospf_elect_bdr (oi, el_list);
ospf_elect_dr (oi, el_list);
new_state = ospf_ism_state (oi);
zlog_info ("DR-Election[2nd]: Backup %s", inet_ntoa (BDR (oi)));
zlog_info ("DR-Election[2nd]: DR %s", inet_ntoa (DR (oi)));
}
list_delete (el_list);
/* if DR or BDR changes, cause AdjOK? neighbor event. */
if (!IPV4_ADDR_SAME (&old_dr, &DR (oi)) ||
!IPV4_ADDR_SAME (&old_bdr, &BDR (oi)))
ospf_dr_change (oi->ospf, oi->nbrs);
if (oi->type == OSPF_IFTYPE_BROADCAST || oi->type == OSPF_IFTYPE_POINTOPOINT)
{
/* Multicast group change. */
if ((old_state != ISM_DR && old_state != ISM_Backup) &&
(new_state == ISM_DR || new_state == ISM_Backup))
ospf_if_add_alldrouters (oi->ospf, oi->address, oi->ifp->ifindex);
else if ((old_state == ISM_DR || old_state == ISM_Backup) &&
(new_state != ISM_DR && new_state != ISM_Backup))
ospf_if_drop_alldrouters (oi->ospf, oi->address, oi->ifp->ifindex);
}
return new_state;
}