ospfd/ospf_gr.h

   1 /*
   2  * OSPF Graceful Restart helper functions.
   3  *
   4  * Copyright (C) 2020-21 Vmware, Inc.
   5  * Rajesh Kumar Girada
   6  *
   7  * This file is part of GNU Zebra.
   8  *
   9  * GNU Zebra is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the
  11  * Free Software Foundation; either version 2, or (at your option) any
  12  * later version.
  13  *
  14  * GNU Zebra is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; see the file COPYING; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #ifndef _ZEBRA_OSPF_GR_H
  25 #define _ZEBRA_OSPF_GR_H
  26
  27 #define OSPF_GR_NOT_HELPER 0
  28 #define OSPF_GR_ACTIVE_HELPER 1
  29
  30 #define OSPF_GR_HELPER_NO_LSACHECK 0
  31 #define OSPF_GR_HELPER_LSACHECK 1
  32
  33 #define OSPF_MAX_GRACE_INTERVAL 1800
  34 #define OSPF_MIN_GRACE_INTERVAL 1
  35 #define OSPF_DFLT_GRACE_INTERVAL 120
  36
  37 enum ospf_helper_exit_reason {
  38         OSPF_GR_HELPER_EXIT_NONE = 0,
  39         OSPF_GR_HELPER_INPROGRESS,
  40         OSPF_GR_HELPER_TOPO_CHG,
  41         OSPF_GR_HELPER_GRACE_TIMEOUT,
  42         OSPF_GR_HELPER_COMPLETED
  43 };
  44
  45 enum ospf_gr_restart_reason {
  46         OSPF_GR_UNKNOWN_RESTART = 0,
  47         OSPF_GR_SW_RESTART = 1,
  48         OSPF_GR_SW_UPGRADE = 2,
  49         OSPF_GR_SWITCH_REDUNDANT_CARD = 3,
  50         OSPF_GR_INVALID_REASON_CODE = 4
  51 };
  52
  53 enum ospf_gr_helper_rejected_reason {
  54         OSPF_HELPER_REJECTED_NONE,
  55         OSPF_HELPER_SUPPORT_DISABLED,
  56         OSPF_HELPER_NOT_A_VALID_NEIGHBOUR,
  57         OSPF_HELPER_PLANNED_ONLY_RESTART,
  58         OSPF_HELPER_TOPO_CHANGE_RTXMT_LIST,
  59         OSPF_HELPER_LSA_AGE_MORE,
  60         OSPF_HELPER_RESTARTING,
  61 };
  62
  63 /* Ref RFC3623 appendex-A */
  64 /* Grace period TLV */
  65 #define GRACE_PERIOD_TYPE 1
  66 #define GRACE_PERIOD_LENGTH 4
  67
  68 struct grace_tlv_graceperiod {
  69         struct tlv_header header;
  70         uint32_t interval;
  71 };
  72
  73 /* Restart reason TLV */
  74 #define RESTART_REASON_TYPE 2
  75 #define RESTART_REASON_LENGTH 1
  76
  77 struct grace_tlv_restart_reason {
  78         struct tlv_header header;
  79         uint8_t reason;
  80         uint8_t reserved[3];
  81 };
  82
  83 /* Restarter ip address TLV */
  84 #define RESTARTER_IP_ADDR_TYPE 3
  85 #define RESTARTER_IP_ADDR_LEN 4
  86
  87 struct grace_tlv_restart_addr {
  88         struct tlv_header header;
  89         struct in_addr addr;
  90 };
  91
  92 struct ospf_helper_info {
  93
  94         /* Grace interval received from
  95          * Restarting Router.
  96          */
  97         uint32_t recvd_grace_period;
  98
  99         /* Grace interval used for grace
 100          * gracetimer.
 101          */
 102         uint32_t actual_grace_period;
 103
 104         /* Grace timer,This Router acts as
 105          * helper until this timer until
 106          * this timer expires.
 107          */
 108         struct thread *t_grace_timer;
 109
 110         /* Helper status */
 111         uint32_t gr_helper_status;
 112
 113         /* Helper exit reason*/
 114         enum ospf_helper_exit_reason helper_exit_reason;
 115
 116         /* Planned/Unplanned restart*/
 117         enum ospf_gr_restart_reason  gr_restart_reason;
 118
 119         /* Helper rejected reason */
 120         enum ospf_gr_helper_rejected_reason rejected_reason;
 121 };
 122
 123 struct advRtr {
 124         struct in_addr advRtrAddr;
 125 };
 126
 127 #define OSPF_HELPER_ENABLE_RTR_COUNT(ospf) (ospf->enable_rtr_list->count)
 128
 129 /* Check for planned restart */
 130 #define OSPF_GR_IS_PLANNED_RESTART(reason)                                     \
 131         ((reason == OSPF_GR_SW_RESTART) || (reason == OSPF_GR_SW_UPGRADE))
 132
 133 /* Check the router is HELPER for current neighbour */
 134 #define OSPF_GR_IS_ACTIVE_HELPER(N)                                                         \
 135         ((N)->gr_helper_info.gr_helper_status == OSPF_GR_ACTIVE_HELPER)
 136
 137 /* Check the LSA is GRACE LSA */
 138 #define IS_GRACE_LSA(lsa)                                                      \
 139         ((lsa->data->type == OSPF_OPAQUE_LINK_LSA)                             \
 140          && (GET_OPAQUE_TYPE(ntohl(lsa->data->id.s_addr))                      \
 141              == OPAQUE_TYPE_GRACE_LSA))
 142
 143 /* Check neighbour is in FULL state */
 144 #define IS_NBR_STATE_FULL(nbr) (nsm_should_adj(nbr) && (nbr->state == NSM_Full))
 145
 146 /* Check neighbour is DR_OTHER and state is 2_WAY */
 147 #define IS_NBR_STATE_2_WAY_WITH_DROTHER(nbr)                                   \
 148         ((ospf_get_nbr_ism_role(nbr) == ISM_DROther)                           \
 149          && (nbr->state == NSM_TwoWay))
 150
 151 #define OSPF_GR_FALSE false
 152 #define OSPF_GR_TRUE true
 153
 154 #define OSPF_GR_SUCCESS 1
 155 #define OSPF_GR_FAILURE 0
 156 #define OSPF_GR_INVALID -1
 157
 158 const char *ospf_exit_reason2str(unsigned int reason);
 159 const char *ospf_restart_reason2str(unsigned int reason);
 160 const char *ospf_rejected_reason2str(unsigned int reason);
 161
 162 extern void ospf_gr_helper_instance_init(struct ospf *ospf);
 163 extern void ospf_gr_helper_instance_stop(struct ospf *ospf);
 164 extern void ospf_gr_helper_init(void);
 165 extern void ospf_gr_helper_stop(void);
 166 extern int ospf_process_grace_lsa(struct ospf *ospf, struct ospf_lsa *lsa,
 167                                   struct ospf_neighbor *nbr);
 168 extern void ospf_gr_helper_exit(struct ospf_neighbor *nbr,
 169                                 enum ospf_helper_exit_reason reason);
 170 extern void ospf_process_maxage_grace_lsa(struct ospf *ospf,
 171                                           struct ospf_lsa *lsa,
 172                                           struct ospf_neighbor *nbr);
 173 extern void ospf_helper_handle_topo_chg(struct ospf *ospf,
 174                                         struct ospf_lsa *lsa);
 175 extern void ospf_gr_helper_support_set(struct ospf *ospf, bool support);
 176 extern void ospf_gr_helper_support_set_per_routerid(struct ospf *ospf,
 177                                                     struct in_addr *rid,
 178                                                     bool support);
 179 extern void ospf_gr_helper_lsa_check_set(struct ospf *ospf, bool lsacheck);
 180 extern void ospf_gr_helper_supported_gracetime_set(struct ospf *ospf,
 181                                                    uint32_t interval);
 182 extern void ospf_gr_helper_set_supported_planned_only_restart(struct ospf *ospf,
 183                                                              bool planned_only);
 184
 185 extern void ospf_gr_check_lsdb_consistency(struct ospf *ospf,
 186                                                   struct ospf_area *area);
 187 extern void ospf_gr_check_adjs(struct ospf *ospf);
 188 extern void ospf_gr_nvm_read(struct ospf *ospf);
 189 extern void ospf_gr_init(void);
 190
 191 #endif /* _ZEBRA_OSPF_GR_H */