lib/rstp-common.h

   1 /*
   2  * Copyright (c) 2011-2015 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) common header file.
  19  *
  20  * Authors:
  21  *         Martino Fornasa <mf@fornasa.it>
  22  *         Daniele Venturino <daniele.venturino@m3s.it>
  23  *         Carlo Andreotti <c.andreotti@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_COMMON_H
  31 #define RSTP_COMMON_H 1
  32
  33 #include "rstp.h"
  34 #include <stdbool.h>
  35 #include <stdint.h>
  36 #include "openvswitch/hmap.h"
  37 #include "openvswitch/list.h"
  38 #include "ovs-atomic.h"
  39 #include "packets.h"
  40
  41 enum admin_port_state {
  42     RSTP_ADMIN_BRIDGE_PORT_STATE_DISABLED = 0,
  43     RSTP_ADMIN_BRIDGE_PORT_STATE_ENABLED = 1
  44 };
  45
  46 enum oper_p2p_mac_state {
  47     RSTP_OPER_P2P_MAC_STATE_DISABLED = 0,
  48     RSTP_OPER_P2P_MAC_STATE_ENABLED = 1
  49 };
  50
  51 /* State enumerations for state machines defined in rstp-state-machines.c */
  52 enum port_receive_state_machine {
  53     PORT_RECEIVE_SM_INIT,
  54     PORT_RECEIVE_SM_DISCARD_EXEC,
  55     PORT_RECEIVE_SM_DISCARD,
  56     PORT_RECEIVE_SM_RECEIVE_EXEC,
  57     PORT_RECEIVE_SM_RECEIVE
  58 };
  59 enum port_transmit_state_machine {
  60     PORT_TRANSMIT_SM_INIT,
  61     PORT_TRANSMIT_SM_TRANSMIT_INIT_EXEC,
  62     PORT_TRANSMIT_SM_TRANSMIT_INIT,
  63     PORT_TRANSMIT_SM_TRANSMIT_PERIODIC_EXEC,
  64     PORT_TRANSMIT_SM_TRANSMIT_PERIODIC,
  65     PORT_TRANSMIT_SM_IDLE_EXEC,
  66     PORT_TRANSMIT_SM_IDLE,
  67     PORT_TRANSMIT_SM_TRANSMIT_CONFIG_EXEC,
  68     PORT_TRANSMIT_SM_TRANSMIT_CONFIG,
  69     PORT_TRANSMIT_SM_TRANSMIT_TCN_EXEC,
  70     PORT_TRANSMIT_SM_TRANSMIT_TCN,
  71     PORT_TRANSMIT_SM_TRANSMIT_RSTP_EXEC,
  72     PORT_TRANSMIT_SM_TRANSMIT_RSTP
  73 };
  74 enum bridge_detection_state_machine {
  75     BRIDGE_DETECTION_SM_INIT,
  76     BRIDGE_DETECTION_SM_EDGE_EXEC,
  77     BRIDGE_DETECTION_SM_EDGE,
  78     BRIDGE_DETECTION_SM_NOT_EDGE_EXEC,
  79     BRIDGE_DETECTION_SM_NOT_EDGE
  80 };
  81 enum port_protocol_migration_state_machine {
  82     PORT_PROTOCOL_MIGRATION_SM_INIT,
  83     PORT_PROTOCOL_MIGRATION_SM_CHECKING_RSTP_EXEC,
  84     PORT_PROTOCOL_MIGRATION_SM_CHECKING_RSTP,
  85     PORT_PROTOCOL_MIGRATION_SM_SELECTING_STP_EXEC,
  86     PORT_PROTOCOL_MIGRATION_SM_SELECTING_STP,
  87     PORT_PROTOCOL_MIGRATION_SM_SENSING_EXEC,
  88     PORT_PROTOCOL_MIGRATION_SM_SENSING
  89 };
  90 enum port_information_state_machine {
  91     PORT_INFORMATION_SM_INIT,
  92     PORT_INFORMATION_SM_DISABLED_EXEC,
  93     PORT_INFORMATION_SM_DISABLED,
  94     PORT_INFORMATION_SM_AGED_EXEC,
  95     PORT_INFORMATION_SM_AGED,
  96     PORT_INFORMATION_SM_UPDATE_EXEC,
  97     PORT_INFORMATION_SM_UPDATE,
  98     PORT_INFORMATION_SM_CURRENT_EXEC,
  99     PORT_INFORMATION_SM_CURRENT,
 100     PORT_INFORMATION_SM_RECEIVE_EXEC,
 101     PORT_INFORMATION_SM_RECEIVE,
 102     PORT_INFORMATION_SM_OTHER_EXEC,
 103     PORT_INFORMATION_SM_OTHER,
 104     PORT_INFORMATION_SM_NOT_DESIGNATED_EXEC,
 105     PORT_INFORMATION_SM_NOT_DESIGNATED,
 106     PORT_INFORMATION_SM_INFERIOR_DESIGNATED_EXEC,
 107     PORT_INFORMATION_SM_INFERIOR_DESIGNATED,
 108     PORT_INFORMATION_SM_REPEATED_DESIGNATED_EXEC,
 109     PORT_INFORMATION_SM_REPEATED_DESIGNATED,
 110     PORT_INFORMATION_SM_SUPERIOR_DESIGNATED_EXEC,
 111     PORT_INFORMATION_SM_SUPERIOR_DESIGNATED
 112 };
 113 enum port_role_selection_state_machine {
 114     PORT_ROLE_SELECTION_SM_INIT,
 115     PORT_ROLE_SELECTION_SM_INIT_BRIDGE_EXEC,
 116     PORT_ROLE_SELECTION_SM_INIT_BRIDGE,
 117     PORT_ROLE_SELECTION_SM_ROLE_SELECTION_EXEC,
 118     PORT_ROLE_SELECTION_SM_ROLE_SELECTION
 119 };
 120 enum port_role_transition_state_machine {
 121     PORT_ROLE_TRANSITION_SM_INIT,
 122     PORT_ROLE_TRANSITION_SM_INIT_PORT_EXEC,
 123     PORT_ROLE_TRANSITION_SM_DISABLE_PORT_EXEC,
 124     PORT_ROLE_TRANSITION_SM_DISABLE_PORT,
 125     PORT_ROLE_TRANSITION_SM_DISABLED_PORT_EXEC,
 126     PORT_ROLE_TRANSITION_SM_DISABLED_PORT,
 127     PORT_ROLE_TRANSITION_SM_ROOT_PORT_EXEC,
 128     PORT_ROLE_TRANSITION_SM_ROOT_PORT,
 129     PORT_ROLE_TRANSITION_SM_REROOT_EXEC,
 130     PORT_ROLE_TRANSITION_SM_ROOT_AGREED_EXEC,
 131     PORT_ROLE_TRANSITION_SM_ROOT_PROPOSED_EXEC,
 132     PORT_ROLE_TRANSITION_SM_ROOT_FORWARD_EXEC,
 133     PORT_ROLE_TRANSITION_SM_ROOT_LEARN_EXEC,
 134     PORT_ROLE_TRANSITION_SM_REROOTED_EXEC,
 135     PORT_ROLE_TRANSITION_SM_DESIGNATED_PORT_EXEC,
 136     PORT_ROLE_TRANSITION_SM_DESIGNATED_PORT,
 137     PORT_ROLE_TRANSITION_SM_DESIGNATED_RETIRED_EXEC,
 138     PORT_ROLE_TRANSITION_SM_DESIGNATED_SYNCED_EXEC,
 139     PORT_ROLE_TRANSITION_SM_DESIGNATED_PROPOSE_EXEC,
 140     PORT_ROLE_TRANSITION_SM_DESIGNATED_FORWARD_EXEC,
 141     PORT_ROLE_TRANSITION_SM_DESIGNATED_LEARN_EXEC,
 142     PORT_ROLE_TRANSITION_SM_DESIGNATED_DISCARD_EXEC,
 143     PORT_ROLE_TRANSITION_SM_ALTERNATE_PORT_EXEC,
 144     PORT_ROLE_TRANSITION_SM_ALTERNATE_PORT,
 145     PORT_ROLE_TRANSITION_SM_ALTERNATE_AGREED_EXEC,
 146     PORT_ROLE_TRANSITION_SM_ALTERNATE_PROPOSED_EXEC,
 147     PORT_ROLE_TRANSITION_SM_BLOCK_PORT_EXEC,
 148     PORT_ROLE_TRANSITION_SM_BLOCK_PORT,
 149     PORT_ROLE_TRANSITION_SM_BACKUP_PORT_EXEC
 150 };
 151 enum port_state_transition_state_machine {
 152     PORT_STATE_TRANSITION_SM_INIT,
 153     PORT_STATE_TRANSITION_SM_DISCARDING_EXEC,
 154     PORT_STATE_TRANSITION_SM_DISCARDING,
 155     PORT_STATE_TRANSITION_SM_LEARNING_EXEC,
 156     PORT_STATE_TRANSITION_SM_LEARNING,
 157     PORT_STATE_TRANSITION_SM_FORWARDING_EXEC,
 158     PORT_STATE_TRANSITION_SM_FORWARDING
 159 };
 160 enum topology_change_state_machine {
 161     TOPOLOGY_CHANGE_SM_INIT,
 162     TOPOLOGY_CHANGE_SM_INACTIVE_EXEC,
 163     TOPOLOGY_CHANGE_SM_INACTIVE,
 164     TOPOLOGY_CHANGE_SM_LEARNING_EXEC,
 165     TOPOLOGY_CHANGE_SM_LEARNING,
 166     TOPOLOGY_CHANGE_SM_DETECTED_EXEC,
 167     TOPOLOGY_CHANGE_SM_ACTIVE_EXEC,
 168     TOPOLOGY_CHANGE_SM_ACTIVE,
 169     TOPOLOGY_CHANGE_SM_ACKNOWLEDGED_EXEC,
 170     TOPOLOGY_CHANGE_SM_PROPAGATING_EXEC,
 171     TOPOLOGY_CHANGE_SM_NOTIFIED_TC_EXEC,
 172     TOPOLOGY_CHANGE_SM_NOTIFIED_TCN_EXEC,
 173 };
 174
 175
 176 /* [17.18.4, 17.13, Table 17-1]. */
 177 struct rstp_times {
 178     /* [17.13.5 - Bridge Forward Delay] The delay (expressed in seconds) used
 179      * by STP Bridges (17.4) to transition Root and Designated Ports to
 180      * Forwarding (Table 17-1).
 181      * Default = 15.0 s. Values in range 4.0 - 30.0
 182      */
 183     uint16_t forward_delay;
 184
 185     /* [17.13.6 - Bridge Hello Time]
 186      * The interval between periodic transmissions of Configuration Messages
 187      * by Designated Ports (Table 17-1).
 188      * Default = 2.0 s. Fixed value
 189      */
 190     uint16_t hello_time;
 191
 192     /* [17.13.8 - Bridge Max Age]
 193      * The maximum age of the information transmitted by the Bridge when it is
 194      * the Root Bridge (Table 17-1).
 195      * Default = 20.0 s. Values in range 6.0 - 40.0 */
 196     uint16_t max_age;
 197
 198     uint16_t message_age;
 199 };
 200
 201 /* Priority vector [17.6] */
 202 struct rstp_priority_vector {
 203     rstp_identifier root_bridge_id;
 204     uint32_t root_path_cost;
 205     rstp_identifier designated_bridge_id;
 206     uint16_t designated_port_id;
 207     uint16_t bridge_port_id;
 208 };
 209
 210 enum rstp_bpdu_type {
 211     CONFIGURATION_BPDU = 0x0,
 212     TOPOLOGY_CHANGE_NOTIFICATION_BPDU = 0x80,
 213     RAPID_SPANNING_TREE_BPDU = 0x2
 214 };
 215
 216 enum rstp_bpdu_flag {
 217     BPDU_FLAG_TOPCHANGE = 0x01,
 218     BPDU_FLAG_PROPOSAL = 0x02,
 219     BPDU_FLAG_LEARNING = 0x10,
 220     BPDU_FLAG_FORWARDING = 0x20,
 221     BPDU_FLAG_AGREEMENT = 0x40,
 222     BPDU_FLAG_TOPCHANGEACK = 0x80
 223 };
 224
 225 /* Rapid Spanning Tree BPDU [9.3.3] */
 226 OVS_PACKED(
 227 struct rstp_bpdu {
 228     ovs_be16 protocol_identifier;
 229     uint8_t protocol_version_identifier;
 230     uint8_t bpdu_type;
 231     uint8_t flags;
 232     ovs_be64 root_bridge_id;
 233     ovs_be32 root_path_cost;
 234     ovs_be64 designated_bridge_id;
 235     ovs_be16 designated_port_id;
 236     ovs_be16 message_age;
 237     ovs_be16 max_age;
 238     ovs_be16 hello_time;
 239     ovs_be16 forward_delay;
 240     uint8_t version1_length;
 241     uint8_t padding[7];
 242 });
 243
 244 enum rstp_info_is {
 245     INFO_IS_DISABLED,
 246     INFO_IS_RECEIVED,
 247     INFO_IS_AGED,
 248     INFO_IS_MINE
 249 };
 250
 251 enum rstp_rcvd_info {
 252     SUPERIOR_DESIGNATED_INFO,
 253     REPEATED_DESIGNATED_INFO,
 254     INFERIOR_DESIGNATED_INFO,
 255     INFERIOR_ROOT_ALTERNATE_INFO,
 256     OTHER_INFO
 257 };
 258
 259 struct rstp_port {
 260     struct ovs_refcount ref_cnt;
 261
 262     struct rstp *rstp OVS_GUARDED_BY(rstp_mutex);
 263     struct hmap_node node OVS_GUARDED_BY(rstp_mutex); /* In rstp->ports. */
 264     void *aux OVS_GUARDED_BY(rstp_mutex);
 265     char *port_name;
 266     struct rstp_bpdu received_bpdu_buffer OVS_GUARDED_BY(rstp_mutex);
 267     /*************************************************************************
 268      * MAC status parameters
 269      ************************************************************************/
 270     /* [6.4.2 - MAC_Operational]
 271      * The value of this parameter is TRUE if [...] the MAC entity can be used
 272      * to transmit and/or receive frames, and its use is permitted by
 273      * management.
 274      */
 275     bool mac_operational OVS_GUARDED_BY(rstp_mutex);
 276
 277     /* [14.8.2.2] Administrative Bridge Port State */
 278     bool is_administrative_bridge_port OVS_GUARDED_BY(rstp_mutex);
 279
 280     /* [6.4.3 - operPointToPointMAC]
 281      *  a) True. The MAC is connected to a point-to-point LAN; i.e., there is
 282      *     at most one other system attached to the LAN.
 283      *  b) False. The MAC is connected to a non-point-to-point LAN; i.e.,
 284      *     there can be more than one other system attached to the LAN.
 285      *
 286      *  If adminPointToPointMAC is set to ForceTrue, then operPointToPointMAC
 287      *  shall be set True. If adminPointToPointMAC is set to ForceFalse, then
 288      *  operPointToPointMAC shall be set False.
 289      */
 290     bool oper_point_to_point_mac OVS_GUARDED_BY(rstp_mutex);
 291
 292     /* [6.4.3 - adminPointToPointMAC]
 293      *  a) ForceTrue. The administrator requires the MAC to be treated as if it
 294      *     is connected to a point-to-point LAN, regardless of any indications
 295      *     to the contrary that are generated by the MAC entity.
 296      *  b) ForceFalse. The administrator requires the MAC to be treated as
 297      *     connected to a non-point-to-point LAN, regardless of any indications
 298      *     to the contrary that are generated by the MAC entity.
 299      *  c) Auto. The administrator requires the point-to-point status of the
 300      *     MAC to be determined in accordance with the specific MAC procedures
 301      *     defined in 6.5.
 302      */
 303     enum rstp_admin_point_to_point_mac_state admin_point_to_point_mac OVS_GUARDED_BY(rstp_mutex);
 304
 305
 306     /*************************************************************************
 307      * [17.3 - RSTP performance parameters] Set by management actions on the
 308      * bridge
 309      *************************************************************************/
 310
 311     /* [17.13.1 - Admin Edge Port]
 312      * The AdminEdgePort parameter for the Port (14.8.2).
 313      */
 314     bool admin_edge OVS_GUARDED_BY(rstp_mutex);
 315
 316     /* [17.13.3 - AutoEdge]
 317      *  The AutoEdgePort parameter for the Port (14.8.2).
 318      */
 319     bool auto_edge OVS_GUARDED_BY(rstp_mutex);
 320
 321
 322     /*************************************************************************
 323      * The following variables are set by management actions on the bridge
 324      ************************************************************************/
 325
 326     /* Port number and priority
 327      * >=1 (max 12 bits [9.2.7])
 328      */
 329     uint16_t port_number OVS_GUARDED_BY(rstp_mutex);
 330
 331     /* Port priority
 332      * Range: 0-240 in steps of 16 (table 17-2)
 333      */
 334     uint8_t priority OVS_GUARDED_BY(rstp_mutex);
 335
 336     /* [17.13.11 - PortPathCost]
 337      * The Port's contribution, when it is the Root Port, to the Root Path Cost
 338      * (17.3.1, 17.5, 17.6) for the Bridge.
 339      */
 340     uint32_t port_path_cost OVS_GUARDED_BY(rstp_mutex);
 341
 342     /*************************************************************************
 343      * The following variables are defined in [17.17 - State machine timers]
 344      ************************************************************************/
 345     /* [17.17.1 - edgeDelayWhile]
 346      * The Edge Delay timer. The time remaining, in the absence of a received
 347      * BPDU, before this port is identified as an operEdgePort.
 348      */
 349     uint16_t edge_delay_while OVS_GUARDED_BY(rstp_mutex);
 350
 351     /* [17.17.2 - fdWhile]
 352      * The Forward Delay timer. Used to delay Port State transitions until
 353      * other Bridges have received spanning tree information.
 354      */
 355     uint16_t fd_while OVS_GUARDED_BY(rstp_mutex);
 356
 357     /* [17.17.3 - helloWhen]
 358      * The Hello timer. Used to ensure that at least one BPDU is transmitted by
 359      * a Designated Port in each HelloTime period.
 360      */
 361     uint16_t hello_when OVS_GUARDED_BY(rstp_mutex);
 362
 363     /* [17.17.4 - mdelayWhile]
 364      * The Migration Delay timer. Used by the Port Protocol Migration state
 365      * machine to allow time for another RSTP Bridge on the same LAN to
 366      * synchronize its migration state with this Port before the receipt of a
 367      * BPDU can cause this Port to change the BPDU types it transmits.
 368      * Initialized to MigrateTime (17.13.9).
 369      */
 370     uint16_t mdelay_while OVS_GUARDED_BY(rstp_mutex);
 371
 372     /* [17.17.5 - rbWhile]
 373      * The Recent Backup timer. Maintained at its initial value, twice
 374      * HelloTime, while the Port is a Backup Port.
 375      */
 376     uint16_t rb_while OVS_GUARDED_BY(rstp_mutex);
 377
 378     /* [17.17.6 - rcvdInfoWhile]
 379      * The Received Info timer. The time remaining before the spanning tree
 380      * information received by this Port [portPriority (17.19.21) and portTimes
 381      * (17.19.22)] is aged out if not refreshed by the receipt of a further
 382      * Configuration Message.
 383      */
 384     uint16_t rcvd_info_while OVS_GUARDED_BY(rstp_mutex);
 385
 386     /* [17.17.7 - rrWhile]
 387      * The Recent Root timer.
 388      */
 389     uint16_t rr_while OVS_GUARDED_BY(rstp_mutex);
 390
 391     /* [17.17.8 - tcWhile]
 392      * The Topology Change timer. TCN Messages are sent while this timer is
 393      * running.
 394      */
 395     uint16_t tc_while OVS_GUARDED_BY(rstp_mutex);
 396
 397
 398     /*************************************************************************
 399      * The following variables are defined in [17.19 - Per-Port variables]
 400      ************************************************************************/
 401
 402     /* [17.19.1 - ageingTime]
 403      * Filtering database entries for this Port are aged out after ageingTime
 404      * has elapsed since they were first created or refreshed by the Learning
 405      * Process.
 406      * The value of this parameter is normally Ageing Time (7.9.2, Table 7-5),
 407      * and is changed to FwdDelay (17.20.6) for a period of FwdDelay after
 408      * fdbFlush (17.19.7) is set by the topology change state machine if
 409      * stpVersion (17.19.7) is TRUE.
 410      */
 411     uint32_t ageing_time OVS_GUARDED_BY(rstp_mutex);
 412
 413     /* [17.19.2 - agree]
 414      * Set if synced is set for all other Ports. An RST BPDU with the Agreement
 415      * flag set is transmitted and proposed is reset when agree is first set,
 416      * and when proposed is set.
 417      * Initialized by Port Information state machine.
 418      */
 419     bool agree OVS_GUARDED_BY(rstp_mutex);
 420
 421     /* [17.19.3 - agreed]
 422      * Set when an RST BPDU is received with a Port Role of Root, Alternate, or
 423      * Backup Port, the Agreement flag set, and a message priority the same or
 424      * worse than the port priority. When agreed is set, the Designated Port
 425      * knows that its neighbouring Bridge has confirmed that it can proceed to
 426      * the Forwarding state without further delay.
 427      * Initialized by Port Information state machine.
 428      */
 429     bool agreed OVS_GUARDED_BY(rstp_mutex);
 430
 431     /* [17.19.4 - designatedPriority]
 432      * The first four components of the Port's designated priority vector
 433      * value, as defined in 17.6. The fifth component of the designated
 434      * priority vector value is portId (17.19.19).
 435      * (Fifth component of the structure must not be used)
 436      */
 437     struct rstp_priority_vector designated_priority_vector OVS_GUARDED_BY(rstp_mutex);
 438
 439     /* [17.19.5 - designatedTimes]
 440      * The designatedTimes variable comprises the set of timer parameter values
 441      * (Message Age, Max Age, Forward Delay, and Hello Time) that used to
 442      * update Port Times when updtInfo is set. Updated by the updtRolesTree()
 443      * procedure (17.21.25).
 444      */
 445     struct rstp_times designated_times OVS_GUARDED_BY(rstp_mutex);
 446
 447     /* [17.19.6 - disputed] */
 448     bool disputed OVS_GUARDED_BY(rstp_mutex);
 449
 450     /* [17.19.7 - fdbFlush]
 451      * A boolean. Set by the topology change state machine to instruct the
 452      * filtering database to remove all entries for this Port, immediately if
 453      * rstpVersion (17.20.11) is TRUE, or by rapid ageing (17.19.1) if
 454      * stpVersion (17.20.12) is TRUE. Reset by the filtering database once the
 455      * entries are
 456      * removed if rstpVersion is TRUE, and immediately if stpVersion is TRUE.
 457      */
 458     uint8_t fdb_flush OVS_GUARDED_BY(rstp_mutex);
 459
 460     /* [17.19.8 - forward]
 461      * Initialized by Port State Transition state machine.
 462      */
 463     bool forward OVS_GUARDED_BY(rstp_mutex);
 464
 465     /* [17.19.9 - forwarding]
 466      * Initialized by Port State Transition state machine.
 467      */
 468     bool forwarding OVS_GUARDED_BY(rstp_mutex);
 469
 470     /* [17.19.10 - infoIs]
 471      * A variable that takes the values Mine, Aged, Received, or Disabled, to
 472      * indicate the origin/state of the Port's Spanning Tree information
 473      * (portInfo) held for the Port, as follows:
 474      *  a) If infoIs is Received, the port has received current (not aged out)
 475      *     information from the Designated Bridge for the attached LAN (a
 476      *     point-to-point bridge link being a special case of a LAN).
 477      *  b) If infoIs is Mine, information for the port has been derived from
 478      *     the Root Port for the Bridge (with the addition of root port cost
 479      *     information). This includes the possibility that the Root Port is
 480      *     "Port 0," i.e., the bridge is the Root Bridge for the Bridged Local
 481      *     Area Network.
 482      *  c) If infoIs is Aged, information from the Root Bridge has been aged
 483      *     out. Just as for "reselect" (see 17.19.34), the state machine does
 484      *     not formally allow the "Aged" state to persist. However, if there is
 485      *     a delay in recomputing the new root port, correct processing of a
 486      *     received BPDU is specified.
 487      *  d) Finally if the port is disabled, infoIs is Disabled.
 488      */
 489     enum rstp_info_is info_is OVS_GUARDED_BY(rstp_mutex);
 490
 491     /* [17.19.11 - learn]
 492      * Initialized by Port State Transition state machine.
 493      */
 494     bool learn OVS_GUARDED_BY(rstp_mutex);
 495
 496     /* [17.19.12 - learning]
 497      * Initialized by Port State Transition state machine.
 498      */
 499     bool learning OVS_GUARDED_BY(rstp_mutex);
 500
 501     /* [17.19.13 - mcheck]
 502      * A boolean. May be set by management to force the Port Protocol Migration
 503      * state machine to transmit RST BPDUs for a MigrateTime (17.13.9) period,
 504      * to test whether all STP Bridges (17.4) on the attached LAN have been
 505      * removed and the Port can continue to transmit RSTP BPDUs. Setting mcheck
 506      * has no effect if stpVersion (17.20.12) is TRUE, i.e., the Bridge is
 507      * operating in STP Compatibility mode.
 508      */
 509     bool mcheck OVS_GUARDED_BY(rstp_mutex);
 510
 511     /* [17.19.14 - msgPriority]
 512      * The first four components of the message priority vector conveyed in a
 513      * received BPDU, as defined in 17.6.
 514      * (Fifth component of the structure must not be used).
 515      */
 516     struct rstp_priority_vector msg_priority OVS_GUARDED_BY(rstp_mutex);
 517
 518     /* [17.19.15 - msgTimes]
 519      * The msgTimes variable comprises the timer parameter values (Message Age,
 520      * Max Age, Forward Delay, and Hello Time) conveyed in a received BPDU.
 521      */
 522     struct rstp_times msg_times OVS_GUARDED_BY(rstp_mutex);
 523
 524     /* [17.19.16 - newInfo]
 525      * A boolean. Set if a BPDU is to be transmitted. Reset by the Port
 526      * Transmit state machine.
 527      */
 528     bool new_info OVS_GUARDED_BY(rstp_mutex);
 529
 530     /* [17.19.17 - operEdge]
 531      * A boolean. The value of the operEdgePort parameter, as determined by the
 532      * operation of the Bridge Detection state machine (17.25).
 533      */
 534     bool oper_edge OVS_GUARDED_BY(rstp_mutex);
 535
 536     /* [17.19.18 - portEnabled]
 537      * A boolean. Set if the Bridge's MAC Relay Entity and Spanning Tree
 538      * Protocol Entity can use the MAC Service provided by the Port's MAC
 539      * entity to transmit and receive frames to and from the attached LAN,
 540      * i.e., portEnabled is TRUE if and only if:
 541      *    a) MAC_Operational (6.4.2) is TRUE; and
 542      *    b) Administrative Bridge Port State (14.8.2.2) for the Port is
 543      *       Enabled; and
 544      *    c) AuthControlledPortStatus is Authorized [if the port is a network
 545      *       access port (IEEE Std 802.1X)].
 546      */
 547     bool port_enabled OVS_GUARDED_BY(rstp_mutex);
 548
 549     /* [17.19.19 - portId]
 550      * The Port Identifier. This variable forms the fifth component of the port
 551      * priority and designated priority vectors defined in 17.6.
 552      */
 553     uint16_t port_id OVS_GUARDED_BY(rstp_mutex);
 554
 555     /* [17.19.21 - portPriority]
 556      * The first four components of the Port's port priority vector value, as
 557      * defined in 17.6.
 558      * (Fifth component of the structure must not be used)
 559      */
 560     struct rstp_priority_vector port_priority OVS_GUARDED_BY(rstp_mutex);
 561
 562     /* [17.19.22 - portTimes]
 563      * The portTimes variable comprises the Port's timer parameter values
 564      * (Message Age, Max Age, Forward Delay, and Hello Time). These timer
 565      * values are used in BPDUs transmitted from the Port.
 566      */
 567     struct rstp_times port_times OVS_GUARDED_BY(rstp_mutex);
 568
 569     /* [17.19.23 - proposed]
 570      * Set when an RST BPDU with a Designated Port role and the Proposal flag
 571      * set is received. If agree is not set, proposed causes sync to be set for
 572      * all other Ports.of the Bridge.
 573      */
 574     bool proposed OVS_GUARDED_BY(rstp_mutex);
 575
 576     /* [17.19.24 - proposing]
 577      * Set by a Designated Port that is not Forwarding, and conveyed to the
 578      * Root Port or Alternate Port of a neighboring Bridge in the Proposal flag
 579      * of an RST BPDU (9.3.3).
 580      */
 581     bool proposing OVS_GUARDED_BY(rstp_mutex);
 582
 583     /* [17.19.25 - rcvdBPDU]
 584      * A boolean. Set by system dependent processes, this variable notifies the
 585      * Port Receive state machine (17.23) when a valid (9.3.4) Configuration,
 586      * TCN, or RST BPDU (9.3.1, 9.3.2, 9.3.3) is received on the Port. Reset
 587      * by the Port Receive state machine.
 588      */
 589     bool rcvd_bpdu OVS_GUARDED_BY(rstp_mutex);
 590
 591     /* [17.19.26 - rcvdInfo]
 592      * Set to the result of the rcvInfo() procedure (17.21.8).
 593      */
 594     enum rstp_rcvd_info rcvd_info OVS_GUARDED_BY(rstp_mutex);
 595
 596     /* [17.19.27 - rcvdMsg] */
 597     bool rcvd_msg OVS_GUARDED_BY(rstp_mutex);
 598
 599     /* [17.19.28 - rcvdRSTP] */
 600     bool rcvd_rstp OVS_GUARDED_BY(rstp_mutex);
 601
 602     /* [17.19.29 - rcvdSTP] */
 603     bool rcvd_stp OVS_GUARDED_BY(rstp_mutex);
 604
 605     /* [17.19.30 - rcvdTc] */
 606     bool rcvd_tc OVS_GUARDED_BY(rstp_mutex);
 607
 608     /* [17.19.31 - rcvdTcAck] */
 609     bool rcvd_tc_ack OVS_GUARDED_BY(rstp_mutex);
 610
 611     /* [17.19.32 - rcvdTcn] */
 612     bool rcvd_tcn OVS_GUARDED_BY(rstp_mutex);
 613
 614     /* [17.19.33 - reRoot] */
 615     bool re_root OVS_GUARDED_BY(rstp_mutex);
 616
 617     /* [17.19.34 - reselect] */
 618     bool reselect OVS_GUARDED_BY(rstp_mutex);
 619
 620     /* [17.19.35 - role]
 621      * The assigned Port Role (17.7).
 622      */
 623     enum rstp_port_role role OVS_GUARDED_BY(rstp_mutex);
 624
 625     /* [17.19.36 - selected]
 626      * A boolean. See 17.28, 17.21.16.
 627      */
 628     bool selected OVS_GUARDED_BY(rstp_mutex);
 629
 630     /* [17.19.37 - selectedRole]
 631      * The newly computed role for the Port (17.7, 17.28, 17.21.25, 17.19.35).
 632      */
 633     enum rstp_port_role selected_role OVS_GUARDED_BY(rstp_mutex);
 634
 635     /* [17.19.38 - sendRSTP]
 636      * A boolean. See 17.24, 17.26.
 637      */
 638     bool send_rstp OVS_GUARDED_BY(rstp_mutex);
 639
 640     /* [17.19.39 - sync]
 641      * A boolean. See 17.10.
 642      */
 643     bool sync OVS_GUARDED_BY(rstp_mutex);
 644
 645     /* [17.19.40 - synced]
 646      * A boolean. See 17.10.
 647      */
 648     bool synced OVS_GUARDED_BY(rstp_mutex);
 649
 650     /* [17.19.41 - tcAck]
 651      * A boolean. Set if a Configuration Message with a topology change
 652      * acknowledge flag set is to be transmitted.
 653      */
 654     bool tc_ack OVS_GUARDED_BY(rstp_mutex);
 655
 656     /* [17.19.42 - tcProp]
 657      * A boolean. Set by the Topology Change state machine of any other Port,
 658      * to indicate that a topology change should be propagated through this
 659      * Port.
 660      */
 661     bool tc_prop OVS_GUARDED_BY(rstp_mutex);
 662
 663     /* [17.19.43 - tick]
 664      * A boolean. See 17.22.
 665      */
 666     bool tick OVS_GUARDED_BY(rstp_mutex);
 667
 668     /* [17.19.44 - txCount]
 669      * A counter. Incremented by the Port Transmission (17.26) state machine on
 670      * every BPDU transmission, and decremented used by the Port Timers state
 671      * machine (17.22) once a second. Transmissions are delayed if txCount
 672      * reaches TxHoldCount (17.13.12).
 673      */
 674     uint16_t tx_count OVS_GUARDED_BY(rstp_mutex);
 675
 676     /* [17.19.45 - updtInfo]
 677      * A boolean. Set by the Port Role Selection state machine (17.28,
 678      * 17.21.25) to tell the Port Information state machine that it should copy
 679      * designatedPriority to portPriority and designatedTimes to portTimes.
 680      */
 681     bool updt_info OVS_GUARDED_BY(rstp_mutex);
 682
 683     /* Counter for RSTP received frames - for rstpd */
 684     uint32_t rx_rstp_bpdu_cnt;
 685
 686     /* Counter for bad RSTP received frames */
 687     uint32_t error_count OVS_GUARDED_BY(rstp_mutex);
 688
 689     /* [14.8.2.1.3] Outputs
 690      * a) Uptime count in seconds of the time elapsed since the Port was last
 691      *    reset or initialized.
 692      */
 693     uint32_t uptime OVS_GUARDED_BY(rstp_mutex);
 694
 695     enum rstp_state rstp_state OVS_GUARDED_BY(rstp_mutex);
 696     bool state_changed OVS_GUARDED_BY(rstp_mutex);
 697
 698     /* Per-port state machines state */
 699     enum port_receive_state_machine port_receive_sm_state OVS_GUARDED_BY(rstp_mutex);
 700     enum port_protocol_migration_state_machine port_protocol_migration_sm_state OVS_GUARDED_BY(rstp_mutex);
 701     enum bridge_detection_state_machine bridge_detection_sm_state OVS_GUARDED_BY(rstp_mutex);
 702     enum port_transmit_state_machine port_transmit_sm_state OVS_GUARDED_BY(rstp_mutex);
 703     enum port_information_state_machine port_information_sm_state OVS_GUARDED_BY(rstp_mutex);
 704     enum port_role_transition_state_machine port_role_transition_sm_state OVS_GUARDED_BY(rstp_mutex);
 705     enum port_state_transition_state_machine port_state_transition_sm_state OVS_GUARDED_BY(rstp_mutex);
 706     enum topology_change_state_machine topology_change_sm_state OVS_GUARDED_BY(rstp_mutex);
 707 };
 708
 709 struct rstp {
 710     struct ovs_list node OVS_GUARDED_BY(rstp_mutex);   /* In rstp instances list */
 711     char *name;     /* Bridge name. */
 712
 713     /* Changes in last SM execution. */
 714     bool changes OVS_GUARDED_BY(rstp_mutex);
 715
 716     /* Per-bridge state machines state */
 717     enum port_role_selection_state_machine port_role_selection_sm_state OVS_GUARDED_BY(rstp_mutex);
 718
 719     /* Bridge MAC address
 720      * (stored in the least significant 48 bits of rstp_identifier).
 721      */
 722     rstp_identifier address OVS_GUARDED_BY(rstp_mutex); /* [7.12.5] */
 723
 724     /* Bridge priority */
 725     uint16_t priority OVS_GUARDED_BY(rstp_mutex);      /* Valid values: 0-61440 in steps of 4096 */
 726
 727     /*************************************************************************
 728      * [17.3 - RSTP performance parameters]
 729      ************************************************************************/
 730
 731     /* [17.13]
 732      * The Spanning Tree Protocol Entity shall be reinitialized, as specified
 733      * by the assertion of BEGIN (17.18.1) in the state machine specification,
 734      * if the following parameters are modified:
 735      *  a) Force Protocol Version (17.13.4)
 736      *
 737      * The spanning tree priority vectors and Port Role assignments for a
 738      * Bridge shall be recomputed, as specified by the operation of the Port
 739      * Role Selection state machine (17.28) by clearing selected (17.19.36) and
 740      * setting reselect (17.19.34) for any Port or Ports for which the
 741      * following parameters are modified:
 742      *  b) Bridge Identifier Priority (17.13.7)
 743      *  c) Port Identifier Priority (17.13.10)
 744      *  d) Port Path Cost (17.13.11)
 745      *
 746      * If the Transmit Hold Count is modified the value of txCount (17.19.44)
 747      * for all Ports shall be set to zero.
 748      *
 749      * The RSTP specification permits changes in other performance parameters
 750      * without exceptional actions.
 751      */
 752
 753
 754     /* [17.13.2 - Ageing Time]
 755      * The Ageing Time parameter for the Bridge (7.9.2, Table 7-5).
 756      */
 757     uint32_t ageing_time OVS_GUARDED_BY(rstp_mutex);
 758
 759     /* [17.13.4 - Force Protocol Version]
 760      * The Force Protocol Version parameter for the Bridge (17.4, 14.8.1).
 761      * This can take the value 0 (STP Compatibility mode) or 2 (the default,
 762      * normal operation).
 763      */
 764     enum rstp_force_protocol_version force_protocol_version OVS_GUARDED_BY(rstp_mutex);
 765
 766     /* [17.13.5 - Bridge Forward Delay]
 767      *  The delay used by STP Bridges (17.4) to transition Root and Designated
 768      * Ports to Forwarding (Table 17-1).
 769      */
 770     uint16_t bridge_forward_delay OVS_GUARDED_BY(rstp_mutex);
 771
 772     /* [17.13.6 - Bridge Hello Time]
 773      *  The interval between periodic transmissions of Configuration Messages
 774      * by Designated Ports (Table 17-1).
 775      */
 776     uint16_t bridge_hello_time OVS_GUARDED_BY(rstp_mutex);
 777
 778     /* [17.13.8 - Bridge Max Age]
 779      * The maximum age of the information transmitted by the Bridge when it is
 780      * the Root Bridge (Table 17-1).
 781      */
 782     uint16_t bridge_max_age OVS_GUARDED_BY(rstp_mutex);
 783
 784     /* [17.13.9 - Migrate Time]
 785      * The initial value of the mdelayWhile and edgeDelayWhile timers (17.17.4,
 786      * 17.17.1), fixed for all RSTP implementations conforming to this
 787      * specification (Table 17-1).
 788      */
 789     uint16_t migrate_time OVS_GUARDED_BY(rstp_mutex);
 790
 791     /* [17.13.12 - Transmit Hold Count]
 792      * The Transmit Hold Count (Table 17-1) used by the Port Transmit state
 793      * machine to limit transmission rate.
 794      */
 795     uint16_t transmit_hold_count OVS_GUARDED_BY(rstp_mutex);
 796
 797
 798     /*************************************************************************
 799      * The following variables are defined in [17.18 - Per-Bridge variables]
 800      ************************************************************************/
 801
 802     /* [17.18.1 - BEGIN]
 803      * A Boolean controlled by the system initialization (17.16). If TRUE
 804      * causes all state machines, including per Port state machines, to
 805      * continuously execute their initial state.
 806      */
 807     bool begin OVS_GUARDED_BY(rstp_mutex);
 808
 809     /* [17.18.2 BridgeIdentifier]
 810      * The unique Bridge Identifier assigned to this Bridge, comprising two
 811      * components: the Bridge Identifier Priority, which may be modified by
 812      * management (see 9.2.5 and 14.8.1.2) and is the more significant when
 813      * Bridge Identifiers are compared, and a component derived from the Bridge
 814      * Address (7.12.5), which guarantees uniqueness of the Bridge Identifiers
 815      * of different Bridges.
 816      */
 817     rstp_identifier bridge_identifier OVS_GUARDED_BY(rstp_mutex);
 818
 819     /* [17.8.3 BridgePriority]
 820      * The bridge priority vector, as defined in 17.6. The first (RootBridgeID)
 821      * and third (DesignatedBridgeID) components are both equal to the value
 822      * of the Bridge Identifier (17.18.2). The other components are zero.
 823      */
 824     struct rstp_priority_vector bridge_priority OVS_GUARDED_BY(rstp_mutex);
 825
 826     /* [17.18.4 - BridgeTimes]
 827      * BridgeTimes comprises four components: the current values of Bridge
 828      * Forward Delay, Bridge Hello Time, Bridge Max Age (17.13, Table 17-1),
 829      * and a Message Age of zero.
 830      */
 831     struct rstp_times bridge_times OVS_GUARDED_BY(rstp_mutex);
 832
 833     /* [17.18.6 - rootPriority]
 834      * The first four components of the Bridge's root priority vector, as
 835      * defined in 17.6.
 836      */
 837     struct rstp_priority_vector root_priority OVS_GUARDED_BY(rstp_mutex);
 838
 839     /* [17.18.5 - rootPortId]
 840      * The Port Identifier of the Root Port. This is the fifth component of
 841      * the root priority vector, as defined in 17.6.
 842      */
 843     uint16_t root_port_id OVS_GUARDED_BY(rstp_mutex);
 844
 845     /* [17.18.7 - rootTimes]
 846      * The rootTimes variable comprises the Bridge's operational timer
 847      * parameter values (Message Age, Max Age, Forward Delay, and Hello Time),
 848      * derived from the values stored in portTimes (17.19.22) for the Root Port
 849      * or from BridgeTimes (17.18.4).
 850      */
 851     struct rstp_times root_times OVS_GUARDED_BY(rstp_mutex);
 852
 853     /* 17.20 State machine conditions and parameters */
 854
 855     /* [17.20.11] rstpVersion
 856      * TRUE if Force Protocol Version (17.13.4) is greater than or equal to 2.
 857      */
 858     bool rstp_version OVS_GUARDED_BY(rstp_mutex);
 859
 860     /* [17.20.12] stpVersion
 861      * TRUE if Force Protocol Version (17.13.4) is less than 2.
 862      */
 863     bool stp_version OVS_GUARDED_BY(rstp_mutex);
 864
 865     /* Ports */
 866     struct hmap ports OVS_GUARDED_BY(rstp_mutex);
 867
 868     struct ovs_refcount ref_cnt;
 869
 870     /* Interface to client. */
 871     void (*send_bpdu)(struct dp_packet *bpdu, void *port_aux, void *rstp_aux);
 872     void *aux;
 873
 874     bool root_changed;
 875     void *old_root_aux;
 876     void *new_root_aux;
 877 };
 878
 879 #endif /* rstp-common.h */