lib/rstp.h

   1 /*
   2  * Copyright (c) 2011-2014 M3S, Srl - Italy
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 /*
  18  * Rapid Spanning Tree Protocol (IEEE 802.1D-2004) public interface (header
  19  * file).
  20  *
  21  * Authors:
  22  *         Martino Fornasa <mf@fornasa.it>
  23  *         Daniele Venturino <daniele.venturino@m3s.it>
  24  *
  25  * References to IEEE 802.1D-2004 standard are enclosed in square brackets.
  26  * E.g. [17.3], [Table 17-1], etc.
  27  *
  28  */
  29
  30 #ifndef RSTP_H
  31 #define RSTP_H 1
  32
  33 #include <stdint.h>
  34 #include <stdbool.h>
  35 #include "compiler.h"
  36 #include "util.h"
  37
  38 /* Thread Safety: Callers passing in RSTP and RSTP port object
  39  * pointers must hold a reference to the passed object to ensure that
  40  * the object does not become stale while it is being accessed. */
  41
  42 extern struct ovs_mutex rstp_mutex;
  43
  44 #define RSTP_MAX_PORTS 4095
  45
  46 struct ofpbuf;
  47
  48 /* Bridge priority defaults [Table 17-2] */
  49 #define RSTP_MIN_PRIORITY 0
  50 #define RSTP_MAX_PRIORITY 61440
  51 #define RSTP_PRIORITY_STEP 4096
  52 #define RSTP_DEFAULT_PRIORITY 32768
  53
  54 /* Port priority defaults [Table 17-2] */
  55 #define RSTP_MIN_PORT_PRIORITY 0
  56 #define RSTP_MAX_PORT_PRIORITY 240
  57 #define RSTP_STEP_PORT_PRIORITY 16
  58 #define RSTP_DEFAULT_PORT_PRIORITY 128
  59
  60 /* Performance parameters defaults. [Table 7-5] and [Table 17-1]
  61  * These values are expressed in seconds.
  62  */
  63 #define RSTP_DEFAULT_AGEING_TIME 300
  64 #define RSTP_MIN_AGEING_TIME 10
  65 #define RSTP_MAX_AGEING_TIME 1000000
  66
  67 #define RSTP_DEFAULT_BRIDGE_MAX_AGE 20
  68 #define RSTP_MIN_BRIDGE_MAX_AGE 6
  69 #define RSTP_MAX_BRIDGE_MAX_AGE 40
  70
  71 #define RSTP_DEFAULT_BRIDGE_FORWARD_DELAY 15
  72 #define RSTP_MIN_BRIDGE_FORWARD_DELAY 4
  73 #define RSTP_MAX_BRIDGE_FORWARD_DELAY 30
  74
  75 #define RSTP_DEFAULT_TRANSMIT_HOLD_COUNT 6
  76 #define RSTP_MIN_TRANSMIT_HOLD_COUNT 1
  77 #define RSTP_MAX_TRANSMIT_HOLD_COUNT 10
  78
  79 #define RSTP_BRIDGE_HELLO_TIME 2 /* Value is fixed [Table 17-1] */
  80
  81 #define RSTP_MIGRATE_TIME 3  /* Value is fixed [Table 17-1] */
  82
  83 /* Port path cost [Table 17-3] */
  84 #define RSTP_MIN_PORT_PATH_COST 1
  85 #define RSTP_MAX_PORT_PATH_COST 200000000
  86 #define RSTP_DEFAULT_PORT_PATH_COST 200000
  87
  88 /* RSTP Bridge identifier [9.2.5].  Top four most significant bits are a
  89  * priority value. The next most significant twelve bits are a locally
  90  * assigned system ID extension. Bottom 48 bits are MAC address of bridge.
  91  */
  92 typedef uint64_t rstp_identifier;
  93
  94 #define RSTP_ID_FMT "%01"PRIx8".%03"PRIx16".%012"PRIx64
  95 #define RSTP_ID_ARGS(rstp_id) \
  96     (uint8_t)((rstp_id) >> 60), \
  97     (uint16_t)(((rstp_id) & 0x0fff000000000000ULL) >> 48), \
  98     (uint64_t)((rstp_id) & 0xffffffffffffULL)
  99
 100 #define RSTP_PORT_ID_FMT "%04"PRIx16
 101
 102 enum rstp_state {
 103     RSTP_DISABLED,
 104     RSTP_LEARNING,
 105     RSTP_FORWARDING,
 106     RSTP_DISCARDING
 107 };
 108
 109 /* Force Protocol Version [17.13.4] */
 110 enum rstp_force_protocol_version {
 111     FPV_STP_COMPATIBILITY = 0,
 112     FPV_DEFAULT = 2
 113 };
 114
 115 enum rstp_port_role {
 116     ROLE_ROOT,
 117     ROLE_DESIGNATED,
 118     ROLE_ALTERNATE,
 119     ROLE_BACKUP,
 120     ROLE_DISABLED
 121 };
 122
 123 struct rstp;
 124 struct rstp_port;
 125 struct ofproto_rstp_settings;
 126
 127 const char *rstp_state_name(enum rstp_state);
 128 const char *rstp_port_role_name(enum rstp_port_role);
 129 static inline bool rstp_forward_in_state(enum rstp_state);
 130 static inline bool rstp_learn_in_state(enum rstp_state);
 131 static inline bool rstp_should_manage_bpdu(enum rstp_state state);
 132
 133 void rstp_init(void)
 134     OVS_EXCLUDED(rstp_mutex);
 135
 136 struct rstp * rstp_create(const char *, rstp_identifier bridge_id,
 137                           void (*send_bpdu)(struct ofpbuf *, void *port_aux,
 138                                             void *rstp_aux),
 139                           void *aux)
 140     OVS_EXCLUDED(rstp_mutex);
 141
 142 struct rstp *rstp_ref(struct rstp *)
 143     OVS_EXCLUDED(rstp_mutex);
 144 void rstp_unref(struct rstp *)
 145     OVS_EXCLUDED(rstp_mutex);
 146
 147 /* Functions used outside RSTP, to call functions defined in
 148    rstp-state-machines.h */
 149 void rstp_tick_timers(struct rstp *)
 150     OVS_EXCLUDED(rstp_mutex);
 151 void rstp_port_received_bpdu(struct rstp_port *, const void *bpdu,
 152                              size_t bpdu_size)
 153     OVS_EXCLUDED(rstp_mutex);
 154 bool rstp_check_and_reset_fdb_flush(struct rstp *)
 155     OVS_EXCLUDED(rstp_mutex);
 156 void *rstp_get_next_changed_port_aux(struct rstp *, struct rstp_port **)
 157     OVS_EXCLUDED(rstp_mutex);
 158 void rstp_port_set_mac_operational(struct rstp_port *,
 159                                    bool new_mac_operational)
 160     OVS_EXCLUDED(rstp_mutex);
 161
 162 /* Bridge setters */
 163 void rstp_set_bridge_address(struct rstp *, rstp_identifier bridge_address)
 164     OVS_EXCLUDED(rstp_mutex);
 165 void rstp_set_bridge_priority(struct rstp *, int new_priority)
 166     OVS_EXCLUDED(rstp_mutex);
 167 void rstp_set_bridge_ageing_time(struct rstp *, int new_ageing_time)
 168     OVS_EXCLUDED(rstp_mutex);
 169 void rstp_set_bridge_force_protocol_version(struct rstp *,
 170                                             enum rstp_force_protocol_version)
 171     OVS_EXCLUDED(rstp_mutex);
 172 void rstp_set_bridge_max_age(struct rstp *, int new_max_age)
 173     OVS_EXCLUDED(rstp_mutex);
 174 void rstp_set_bridge_forward_delay(struct rstp *, int new_forward_delay)
 175     OVS_EXCLUDED(rstp_mutex);
 176 void rstp_set_bridge_transmit_hold_count(struct rstp *,
 177                                          int new_transmit_hold_count)
 178     OVS_EXCLUDED(rstp_mutex);
 179
 180 /* Bridge getters */
 181 const char * rstp_get_name(const struct rstp *)
 182     OVS_EXCLUDED(rstp_mutex);
 183 rstp_identifier rstp_get_root_id(const struct rstp *)
 184     OVS_EXCLUDED(rstp_mutex);
 185 rstp_identifier rstp_get_bridge_id(const struct rstp *)
 186     OVS_EXCLUDED(rstp_mutex);
 187 rstp_identifier rstp_get_designated_id(const struct rstp *)
 188     OVS_EXCLUDED(rstp_mutex);
 189 uint32_t rstp_get_root_path_cost(const struct rstp *)
 190     OVS_EXCLUDED(rstp_mutex);
 191 uint16_t rstp_get_designated_port_id(const struct rstp *)
 192     OVS_EXCLUDED(rstp_mutex);
 193 uint16_t rstp_get_bridge_port_id(const struct rstp *)
 194     OVS_EXCLUDED(rstp_mutex);
 195 struct rstp_port * rstp_get_root_port(struct rstp *)
 196     OVS_EXCLUDED(rstp_mutex);
 197 rstp_identifier rstp_get_designated_root(const struct rstp *)
 198     OVS_EXCLUDED(rstp_mutex);
 199 bool rstp_is_root_bridge(const struct rstp *)
 200     OVS_EXCLUDED(rstp_mutex);
 201
 202 /* RSTP ports */
 203 struct rstp_port * rstp_add_port(struct rstp *)
 204     OVS_EXCLUDED(rstp_mutex);
 205 struct rstp_port *rstp_port_ref(const struct rstp_port *)
 206     OVS_EXCLUDED(rstp_mutex);
 207 void rstp_port_unref(struct rstp_port *)
 208     OVS_EXCLUDED(rstp_mutex);
 209
 210 uint32_t rstp_convert_speed_to_cost(unsigned int speed);
 211
 212 void rstp_port_set(struct rstp_port *, uint16_t port_num, int priority,
 213                    uint32_t path_cost, bool is_admin_edge, bool is_auto_edge,
 214                    bool do_mcheck, void *aux)
 215     OVS_EXCLUDED(rstp_mutex);
 216
 217 enum rstp_state rstp_port_get_state(const struct rstp_port *)
 218     OVS_EXCLUDED(rstp_mutex);
 219
 220 void rstp_port_get_status(const struct rstp_port *, uint16_t *id,
 221                           enum rstp_state *state, enum rstp_port_role *role,
 222                           rstp_identifier *designated_bridge_id,
 223                           uint16_t *designated_port_id,
 224                           uint32_t *designated_path_cost, int *tx_count,
 225                           int *rx_count, int *error_count, int *uptime)
 226     OVS_EXCLUDED(rstp_mutex);
 227
 228 void * rstp_get_port_aux(struct rstp *rstp, uint16_t port_number)
 229     OVS_EXCLUDED(rstp_mutex);
 230
 231 \f
 232 /* Internal API for rstp-state-machines.c */
 233
 234 void rstp_port_set_state__(struct rstp_port *, enum rstp_state state)
 235     OVS_REQUIRES(rstp_mutex);
 236
 237 \f
 238 /* Internal API for test-rstp.c */
 239
 240 struct rstp_port *rstp_get_port(struct rstp *rstp, uint16_t port_number)
 241     OVS_EXCLUDED(rstp_mutex);
 242 void reinitialize_port(struct rstp_port *p)
 243     OVS_EXCLUDED(rstp_mutex);
 244
 245 int rstp_port_get_number(const struct rstp_port *)
 246     OVS_EXCLUDED(rstp_mutex);
 247 void rstp_port_set_priority(struct rstp_port *port, int priority)
 248     OVS_EXCLUDED(rstp_mutex);
 249 void rstp_port_set_aux(struct rstp_port *p, void *aux)
 250     OVS_EXCLUDED(rstp_mutex);
 251 void rstp_port_set_path_cost(struct rstp_port *port, uint32_t path_cost)
 252     OVS_EXCLUDED(rstp_mutex);
 253 void rstp_port_set_state(struct rstp_port *p, enum rstp_state state)
 254     OVS_EXCLUDED(rstp_mutex);
 255
 256 \f
 257 /* Inline functions. */
 258 /* Returns true if 'state' is one in which BPDU packets should be received
 259  * and transmitted on a port, false otherwise.
 260  */
 261 static inline bool
 262 rstp_should_manage_bpdu(enum rstp_state state)
 263 {
 264     return (state == RSTP_DISCARDING || state == RSTP_LEARNING ||
 265             state == RSTP_FORWARDING);
 266 }
 267
 268 /* Returns true if 'state' is one in which packets received on a port should
 269  * be forwarded, false otherwise.
 270  *
 271  * Returns true if 'state' is RSTP_DISABLED, since presumably in that case the
 272  * port should still work, just not have RSTP applied to it.
 273  */
 274 static inline bool
 275 rstp_forward_in_state(enum rstp_state state)
 276 {
 277     return (state == RSTP_DISABLED || state == RSTP_FORWARDING);
 278 }
 279
 280 /* Returns true if 'state' is one in which MAC learning should be done on
 281  * packets received on a port, false otherwise.
 282  *
 283  * Returns true if 'state' is RSTP_DISABLED, since presumably in that case the
 284  * port should still work, just not have RSTP applied to it. */
 285 static inline bool
 286 rstp_learn_in_state(enum rstp_state state)
 287 {
 288     return (state == RSTP_DISABLED || state == RSTP_LEARNING ||
 289             state == RSTP_FORWARDING);
 290 }
 291
 292 #endif /* rstp.h */