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                 if (T)                                                         \
  35                         THREAD_TIMER_OFF(T);                                   \
  36         } while (0)
  37
  38 #define BGP_EVENT_ADD(P, E)                                                    \
  39         do {                                                                   \
  40                 if ((P)->status != Deleted)                                    \
  41                         thread_add_event(bm->master, bgp_event, (P), (E),      \
  42                                          NULL);                                \
  43         } while (0)
  44
  45 #define BGP_EVENT_FLUSH(P)                                                     \
  46         do {                                                                   \
  47                 assert(peer);                                                  \
  48                 thread_cancel_event(bm->master, (P));                          \
  49         } while (0)
  50
  51 #define BGP_MSEC_JITTER 10
  52
  53 /* Status codes for bgp_event_update() */
  54 #define FSM_PEER_NOOP           0
  55 #define FSM_PEER_STOPPED        1
  56 #define FSM_PEER_TRANSFERRED    2
  57 #define FSM_PEER_TRANSITIONED   3
  58
  59 #define BGP_PEER_GR_HELPER_ENABLE(peer) \
  60         do {            \
  61                 UNSET_FLAG( \
  62                         peer->peer_gr_new_status_flag,          \
  63                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART);       \
  64                 SET_FLAG( \
  65                         peer->peer_gr_new_status_flag,  \
  66                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  67         } while (0)
  68
  69 #define BGP_PEER_GR_ENABLE(peer)\
  70         do {                            \
  71                 SET_FLAG(   \
  72                         peer->peer_gr_new_status_flag,  \
  73                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART); \
  74                 UNSET_FLAG( \
  75                         peer->peer_gr_new_status_flag,  \
  76                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  77         } while (0)
  78
  79 #define BGP_PEER_GR_DISABLE(peer)\
  80         do {                            \
  81                 UNSET_FLAG( \
  82                         peer->peer_gr_new_status_flag,  \
  83                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART);\
  84                 UNSET_FLAG(\
  85                         peer->peer_gr_new_status_flag, \
  86                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  87         } while (0)
  88
  89 #define BGP_PEER_GR_GLOBAL_INHERIT_SET(peer) \
  90                         SET_FLAG(peer->peer_gr_new_status_flag, \
  91                                 PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)
  92
  93 #define BGP_PEER_GR_GLOBAL_INHERIT_UNSET(peer)  \
  94                         UNSET_FLAG(peer->peer_gr_new_status_flag, \
  95                                 PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)
  96
  97 #define BGP_PEER_GRACEFUL_RESTART_CAPABLE(peer)                         \
  98         (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_ADV) &&                 \
  99          CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV))
 100
 101 #define BGP_PEER_RESTARTING_MODE(peer)\
 102         (CHECK_FLAG(peer->flags, PEER_FLAG_GRACEFUL_RESTART) && \
 103          CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_ADV) &&     \
 104          !CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_RCV))
 105
 106 #define BGP_PEER_HELPER_MODE(peer)\
 107         (CHECK_FLAG(peer->flags, PEER_FLAG_GRACEFUL_RESTART_HELPER) && \
 108          CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_RCV) &&           \
 109          !CHECK_FLAG(peer->cap, PEER_CAP_RESTART_BIT_ADV))
 110
 111 /* Prototypes. */
 112 extern void bgp_fsm_event_update(struct peer *peer, int valid);
 113 extern int bgp_event(struct thread *);
 114 extern int bgp_event_update(struct peer *, int event);
 115 extern int bgp_stop(struct peer *peer);
 116 extern void bgp_timer_set(struct peer *);
 117 extern int bgp_routeadv_timer(struct thread *);
 118 extern void bgp_fsm_change_status(struct peer *peer, int status);
 119 extern const char *const peer_down_str[];
 120 extern void bgp_update_delay_end(struct bgp *);
 121 extern void bgp_maxmed_update(struct bgp *);
 122 extern int bgp_maxmed_onstartup_configured(struct bgp *);
 123 extern int bgp_maxmed_onstartup_active(struct bgp *);
 124
 125 /**
 126  * Start the route advertisement timer (that honors MRAI) for all the
 127  * peers. Typically called at the end of initial convergence, coming
 128  * out of read-only mode.
 129  */
 130 extern void bgp_start_routeadv(struct bgp *);
 131
 132 /**
 133  * See if the route advertisement timer needs to be adjusted for a
 134  * peer. For example, if the last update was written to the peer a
 135  * long while back, we don't need to wait for the periodic advertisement
 136  * timer to expire to send the new set of prefixes. It should fire
 137  * instantly and updates should go out sooner.
 138  */
 139 extern void bgp_adjust_routeadv(struct peer *);
 140
 141 #include "hook.h"
 142 DECLARE_HOOK(peer_backward_transition, (struct peer *peer), (peer))
 143 DECLARE_HOOK(peer_established, (struct peer *peer), (peer))
 144
 145 int bgp_gr_update_all(struct bgp *bgp, int global_gr_cmd);
 146 int bgp_neighbor_graceful_restart(struct peer *peer,
 147                         int peer_gr_cmd);
 148 unsigned int bgp_peer_gr_action(struct peer *peer,
 149                 int old_peer_state, int new_peer_state);
 150 void bgp_peer_move_to_gr_mode(struct peer *peer, int new_state);
 151 unsigned int bgp_peer_gr_helper_enable(struct peer *peer);
 152 unsigned int bgp_peer_gr_enable(struct peer *peer);
 153 unsigned int bgp_peer_gr_global_inherit(struct peer *peer);
 154 unsigned int bgp_peer_gr_disable(struct peer *peer);
 155 enum peer_mode bgp_peer_gr_mode_get(struct peer *peer);
 156 enum global_mode bgp_global_gr_mode_get(struct bgp *bgp);
 157 enum peer_mode bgp_get_peer_gr_mode_from_flags(struct peer *peer);
 158 unsigned int bgp_peer_gr_global_inherit_unset(struct peer *peer);
 159 int bgp_gr_lookup_n_update_all_peer(struct bgp *bgp,
 160                 enum global_mode global_new_state,
 161                 enum global_mode global_old_state);
 162 void bgp_peer_gr_flags_update(struct peer *peer);
 163 const char *print_peer_gr_mode(enum peer_mode pr_mode);
 164 const char *print_peer_gr_cmd(enum peer_gr_command pr_gr_cmd);
 165 const char *print_global_gr_mode(enum global_mode gl_mode);
 166 const char *print_global_gr_cmd(enum global_gr_command gl_gr_cmd);
 167 #endif /* _QUAGGA_BGP_FSM_H */