bgpd/bgp_fsm.h

   1 /* BGP-4 Finite State Machine
   2  * From RFC1771 [A Border Gateway Protocol 4 (BGP-4)]
   3  * Copyright (C) 1998 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef _QUAGGA_BGP_FSM_H
  23 #define _QUAGGA_BGP_FSM_H
  24
  25 /* Macro for BGP read, write and timer thread.  */
  26 #define BGP_TIMER_ON(T, F, V)                                                  \
  27         do {                                                                   \
  28                 if ((peer->status != Deleted))                                 \
  29                         thread_add_timer(bm->master, (F), peer, (V), &(T));    \
  30         } while (0)
  31
  32 #define BGP_TIMER_OFF(T)                                                       \
  33         do {                                                                   \
  34                 THREAD_OFF((T));                                               \
  35         } while (0)
  36
  37 #define BGP_EVENT_ADD(P, E)                                                    \
  38         do {                                                                   \
  39                 if ((P)->status != Deleted)                                    \
  40                         thread_add_event(bm->master, bgp_event, (P), (E),      \
  41                                          NULL);                                \
  42         } while (0)
  43
  44 #define BGP_EVENT_FLUSH(P)                                                     \
  45         do {                                                                   \
  46                 assert(peer);                                                  \
  47                 thread_cancel_event_ready(bm->master, (P));                    \
  48         } while (0)
  49
  50 #define BGP_UPDATE_GROUP_TIMER_ON(T, F)                                        \
  51         do {                                                                   \
  52                 if (BGP_SUPPRESS_FIB_ENABLED(peer->bgp) &&                     \
  53                     PEER_ROUTE_ADV_DELAY(peer))                                \
  54                         thread_add_timer_msec(bm->master, (F), peer,           \
  55                                 (BGP_DEFAULT_UPDATE_ADVERTISEMENT_TIME * 1000),\
  56                                 (T));                                          \
  57                 else                                                           \
  58                         thread_add_timer_msec(bm->master, (F), peer,           \
  59                                               0, (T));                         \
  60         } while (0)                                                            \
  61
  62 #define BGP_MSEC_JITTER 10
  63
  64 /* Status codes for bgp_event_update() */
  65 #define FSM_PEER_NOOP           0
  66 #define FSM_PEER_STOPPED        1
  67 #define FSM_PEER_TRANSFERRED    2
  68 #define FSM_PEER_TRANSITIONED   3
  69
  70 #define BGP_PEER_GR_HELPER_ENABLE(peer) \
  71         do {            \
  72                 UNSET_FLAG( \
  73                         peer->peer_gr_new_status_flag,          \
  74                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART);       \
  75                 SET_FLAG( \
  76                         peer->peer_gr_new_status_flag,  \
  77                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  78         } while (0)
  79
  80 #define BGP_PEER_GR_ENABLE(peer)\
  81         do {                            \
  82                 SET_FLAG(   \
  83                         peer->peer_gr_new_status_flag,  \
  84                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART); \
  85                 UNSET_FLAG( \
  86                         peer->peer_gr_new_status_flag,  \
  87                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  88         } while (0)
  89
  90 #define BGP_PEER_GR_DISABLE(peer)\
  91         do {                            \
  92                 UNSET_FLAG( \
  93                         peer->peer_gr_new_status_flag,  \
  94                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART);\
  95                 UNSET_FLAG(\
  96                         peer->peer_gr_new_status_flag, \
  97                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  98         } while (0)
  99
 100 #define BGP_PEER_GR_GLOBAL_INHERIT_SET(peer) \
 101                         SET_FLAG(peer->peer_gr_new_status_flag, \
 102                                 PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)
 103
 104 #define BGP_PEER_GR_GLOBAL_INHERIT_UNSET(peer)  \
 105                         UNSET_FLAG(peer->peer_gr_new_status_flag, \
 106                                 PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)
 107
 108 #define BGP_PEER_GRACEFUL_RESTART_CAPABLE(peer)                                \
 109         (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_ADV)                           \
 110          && CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV))
 111
 112 #define BGP_PEER_RESTARTING_MODE(peer)                                         \
 113         (CHECK_FLAG(peer->flags, PEER_FLAG_GRACEFUL_RESTART)                   \
 114          && CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_ADV)                    \
 115          && !CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_RCV))
 116
 117 #define BGP_PEER_HELPER_MODE(peer)                                             \
 118         (CHECK_FLAG(peer->flags, PEER_FLAG_GRACEFUL_RESTART_HELPER)            \
 119          && CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_RCV)                    \
 120          && !CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_ADV))
 121
 122 /* Prototypes. */
 123
 124 /*
 125  * Update FSM for peer based on whether we have valid nexthops or not.
 126  */
 127 extern void bgp_fsm_nht_update(struct peer *peer, bool has_valid_nexthops);
 128 extern void bgp_event(struct thread *);
 129 extern int bgp_event_update(struct peer *, enum bgp_fsm_events event);
 130 extern int bgp_stop(struct peer *peer);
 131 extern void bgp_timer_set(struct peer *);
 132 extern void bgp_routeadv_timer(struct thread *);
 133 extern void bgp_fsm_change_status(struct peer *peer, int status);
 134 extern const char *const peer_down_str[];
 135 extern void bgp_update_delay_end(struct bgp *);
 136 extern void bgp_maxmed_update(struct bgp *);
 137 extern bool bgp_maxmed_onstartup_configured(struct bgp *);
 138 extern bool bgp_maxmed_onstartup_active(struct bgp *);
 139 extern int bgp_fsm_error_subcode(int status);
 140
 141 /**
 142  * Start the route advertisement timer (that honors MRAI) for all the
 143  * peers. Typically called at the end of initial convergence, coming
 144  * out of read-only mode.
 145  */
 146 extern void bgp_start_routeadv(struct bgp *);
 147
 148 /**
 149  * See if the route advertisement timer needs to be adjusted for a
 150  * peer. For example, if the last update was written to the peer a
 151  * long while back, we don't need to wait for the periodic advertisement
 152  * timer to expire to send the new set of prefixes. It should fire
 153  * instantly and updates should go out sooner.
 154  */
 155 extern void bgp_adjust_routeadv(struct peer *);
 156
 157 #include "hook.h"
 158 DECLARE_HOOK(peer_backward_transition, (struct peer *peer), (peer));
 159 DECLARE_HOOK(peer_established, (struct peer *peer), (peer));
 160
 161 int bgp_gr_update_all(struct bgp *bgp, int global_gr_cmd);
 162 int bgp_neighbor_graceful_restart(struct peer *peer, int peer_gr_cmd);
 163 unsigned int bgp_peer_gr_action(struct peer *peer,
 164                 int old_peer_state, int new_peer_state);
 165 void bgp_peer_move_to_gr_mode(struct peer *peer, int new_state);
 166 unsigned int bgp_peer_gr_helper_enable(struct peer *peer);
 167 unsigned int bgp_peer_gr_enable(struct peer *peer);
 168 unsigned int bgp_peer_gr_global_inherit(struct peer *peer);
 169 unsigned int bgp_peer_gr_disable(struct peer *peer);
 170 enum peer_mode bgp_peer_gr_mode_get(struct peer *peer);
 171 enum global_mode bgp_global_gr_mode_get(struct bgp *bgp);
 172 enum peer_mode bgp_get_peer_gr_mode_from_flags(struct peer *peer);
 173 unsigned int bgp_peer_gr_global_inherit_unset(struct peer *peer);
 174 int bgp_gr_lookup_n_update_all_peer(struct bgp *bgp,
 175                 enum global_mode global_new_state,
 176                 enum global_mode global_old_state);
 177 void bgp_peer_gr_flags_update(struct peer *peer);
 178 const char *print_peer_gr_mode(enum peer_mode pr_mode);
 179 const char *print_peer_gr_cmd(enum peer_gr_command pr_gr_cmd);
 180 const char *print_global_gr_mode(enum global_mode gl_mode);
 181 const char *print_global_gr_cmd(enum global_gr_command gl_gr_cmd);
 182 int bgp_peer_reg_with_nht(struct peer *peer);
 183 #endif /* _QUAGGA_BGP_FSM_H */