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_EVENT_ADD(P, E)                                                    \
  33         do {                                                                   \
  34                 if ((P)->status != Deleted)                                    \
  35                         thread_add_event(bm->master, bgp_event, (P), (E),      \
  36                                          NULL);                                \
  37         } while (0)
  38
  39 #define BGP_EVENT_FLUSH(P)                                                     \
  40         do {                                                                   \
  41                 assert(peer);                                                  \
  42                 thread_cancel_event_ready(bm->master, (P));                    \
  43         } while (0)
  44
  45 #define BGP_UPDATE_GROUP_TIMER_ON(T, F)                                        \
  46         do {                                                                   \
  47                 if (BGP_SUPPRESS_FIB_ENABLED(peer->bgp) &&                     \
  48                     PEER_ROUTE_ADV_DELAY(peer))                                \
  49                         thread_add_timer_msec(bm->master, (F), peer,           \
  50                                 (BGP_DEFAULT_UPDATE_ADVERTISEMENT_TIME * 1000),\
  51                                 (T));                                          \
  52                 else                                                           \
  53                         thread_add_timer_msec(bm->master, (F), peer,           \
  54                                               0, (T));                         \
  55         } while (0)                                                            \
  56
  57 #define BGP_MSEC_JITTER 10
  58
  59 /* Status codes for bgp_event_update() */
  60 #define FSM_PEER_NOOP           0
  61 #define FSM_PEER_STOPPED        1
  62 #define FSM_PEER_TRANSFERRED    2
  63 #define FSM_PEER_TRANSITIONED   3
  64
  65 #define BGP_PEER_GR_HELPER_ENABLE(peer) \
  66         do {            \
  67                 UNSET_FLAG( \
  68                         peer->peer_gr_new_status_flag,          \
  69                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART);       \
  70                 SET_FLAG( \
  71                         peer->peer_gr_new_status_flag,  \
  72                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  73         } while (0)
  74
  75 #define BGP_PEER_GR_ENABLE(peer)\
  76         do {                            \
  77                 SET_FLAG(   \
  78                         peer->peer_gr_new_status_flag,  \
  79                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART); \
  80                 UNSET_FLAG( \
  81                         peer->peer_gr_new_status_flag,  \
  82                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  83         } while (0)
  84
  85 #define BGP_PEER_GR_DISABLE(peer)\
  86         do {                            \
  87                 UNSET_FLAG( \
  88                         peer->peer_gr_new_status_flag,  \
  89                         PEER_GRACEFUL_RESTART_NEW_STATE_RESTART);\
  90                 UNSET_FLAG(\
  91                         peer->peer_gr_new_status_flag, \
  92                         PEER_GRACEFUL_RESTART_NEW_STATE_HELPER);\
  93         } while (0)
  94
  95 #define BGP_PEER_GR_GLOBAL_INHERIT_SET(peer) \
  96                         SET_FLAG(peer->peer_gr_new_status_flag, \
  97                                 PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)
  98
  99 #define BGP_PEER_GR_GLOBAL_INHERIT_UNSET(peer)  \
 100                         UNSET_FLAG(peer->peer_gr_new_status_flag, \
 101                                 PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)
 102
 103 #define BGP_PEER_GRACEFUL_RESTART_CAPABLE(peer)                                \
 104         (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_ADV)                           \
 105          && CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV))
 106
 107 #define BGP_PEER_RESTARTING_MODE(peer)                                         \
 108         (CHECK_FLAG(peer->flags, PEER_FLAG_GRACEFUL_RESTART) &&                \
 109          CHECK_FLAG(peer->cap, PEER_CAP_GRACEFUL_RESTART_R_BIT_ADV) &&         \
 110          !CHECK_FLAG(peer->cap, PEER_CAP_GRACEFUL_RESTART_R_BIT_RCV))
 111
 112 #define BGP_PEER_HELPER_MODE(peer)                                             \
 113         (CHECK_FLAG(peer->flags, PEER_FLAG_GRACEFUL_RESTART_HELPER) &&         \
 114          CHECK_FLAG(peer->cap, PEER_CAP_GRACEFUL_RESTART_R_BIT_RCV) &&         \
 115          !CHECK_FLAG(peer->cap, PEER_CAP_GRACEFUL_RESTART_R_BIT_ADV))
 116
 117 /* Prototypes. */
 118
 119 /*
 120  * Update FSM for peer based on whether we have valid nexthops or not.
 121  */
 122 extern void bgp_fsm_nht_update(struct peer *peer, bool has_valid_nexthops);
 123 extern void bgp_event(struct thread *);
 124 extern int bgp_event_update(struct peer *, enum bgp_fsm_events event);
 125 extern int bgp_stop(struct peer *peer);
 126 extern void bgp_timer_set(struct peer *);
 127 extern void bgp_routeadv_timer(struct thread *);
 128 extern void bgp_fsm_change_status(struct peer *peer,
 129                                   enum bgp_fsm_status status);
 130 extern const char *const peer_down_str[];
 131 extern void bgp_update_delay_end(struct bgp *);
 132 extern void bgp_maxmed_update(struct bgp *);
 133 extern bool bgp_maxmed_onstartup_configured(struct bgp *);
 134 extern bool bgp_maxmed_onstartup_active(struct bgp *);
 135 extern int bgp_fsm_error_subcode(int status);
 136
 137 /**
 138  * Start the route advertisement timer (that honors MRAI) for all the
 139  * peers. Typically called at the end of initial convergence, coming
 140  * out of read-only mode.
 141  */
 142 extern void bgp_start_routeadv(struct bgp *);
 143
 144 /**
 145  * See if the route advertisement timer needs to be adjusted for a
 146  * peer. For example, if the last update was written to the peer a
 147  * long while back, we don't need to wait for the periodic advertisement
 148  * timer to expire to send the new set of prefixes. It should fire
 149  * instantly and updates should go out sooner.
 150  */
 151 extern void bgp_adjust_routeadv(struct peer *);
 152
 153 #include "hook.h"
 154 DECLARE_HOOK(peer_backward_transition, (struct peer *peer), (peer));
 155 DECLARE_HOOK(peer_established, (struct peer *peer), (peer));
 156
 157 int bgp_gr_update_all(struct bgp *bgp, int global_gr_cmd);
 158 int bgp_neighbor_graceful_restart(struct peer *peer, int peer_gr_cmd);
 159 unsigned int bgp_peer_gr_action(struct peer *peer,
 160                 int old_peer_state, int new_peer_state);
 161 void bgp_peer_move_to_gr_mode(struct peer *peer, int new_state);
 162 unsigned int bgp_peer_gr_helper_enable(struct peer *peer);
 163 unsigned int bgp_peer_gr_enable(struct peer *peer);
 164 unsigned int bgp_peer_gr_global_inherit(struct peer *peer);
 165 unsigned int bgp_peer_gr_disable(struct peer *peer);
 166 enum peer_mode bgp_peer_gr_mode_get(struct peer *peer);
 167 enum global_mode bgp_global_gr_mode_get(struct bgp *bgp);
 168 enum peer_mode bgp_get_peer_gr_mode_from_flags(struct peer *peer);
 169 unsigned int bgp_peer_gr_global_inherit_unset(struct peer *peer);
 170 int bgp_gr_lookup_n_update_all_peer(struct bgp *bgp,
 171                 enum global_mode global_new_state,
 172                 enum global_mode global_old_state);
 173 void bgp_peer_gr_flags_update(struct peer *peer);
 174 const char *print_peer_gr_mode(enum peer_mode pr_mode);
 175 const char *print_peer_gr_cmd(enum peer_gr_command pr_gr_cmd);
 176 const char *print_global_gr_mode(enum global_mode gl_mode);
 177 const char *print_global_gr_cmd(enum global_gr_command gl_gr_cmd);
 178 int bgp_peer_reg_with_nht(struct peer *peer);
 179
 180 extern void bgp_peer_update_orr_active_roots(struct peer *peer);
 181 #endif /* _QUAGGA_BGP_FSM_H */