ospfd/ospf_api.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * API message handling module for OSPF daemon and client.
   4  * Copyright (C) 2001, 2002 Ralph Keller
   5  * Copyright (c) 2022, LabN Consulting, L.L.C.
   6  */
   7
   8
   9 /* This file is used both by the OSPFd and client applications to
  10    define message formats used for communication. */
  11
  12 #ifndef _OSPF_API_H
  13 #define _OSPF_API_H
  14
  15 #include <zebra.h>
  16 #include "ospf_lsa.h"
  17
  18 #define OSPF_API_VERSION           1
  19
  20 /* MTYPE definition is not reflected to "memory.h". */
  21 #define MTYPE_OSPF_API_MSG      MTYPE_TMP
  22 #define MTYPE_OSPF_API_FIFO     MTYPE_TMP
  23
  24 /* Default API server port to accept connection request from client-side. */
  25 /* This value could be overridden by "ospfapi" entry in "/etc/services". */
  26 #define OSPF_API_SYNC_PORT      2607
  27
  28 /* -----------------------------------------------------------
  29  * Generic messages
  30  * -----------------------------------------------------------
  31  */
  32
  33 /* Message header structure, fields are in network byte order and
  34    aligned to four octets. */
  35 struct apimsghdr {
  36         uint8_t version; /* OSPF API protocol version */
  37         uint8_t msgtype; /* Type of message */
  38         uint16_t msglen; /* Length of message w/o header */
  39         uint32_t msgseq; /* Sequence number */
  40 };
  41
  42 /* Message representation with header and body */
  43 struct msg {
  44         struct msg *next; /* to link into fifo */
  45
  46         /* Message header */
  47         struct apimsghdr hdr;
  48
  49         /* Message body */
  50         struct stream *s;
  51 };
  52
  53 /* Prototypes for generic messages. */
  54 extern struct msg *msg_new(uint8_t msgtype, void *msgbody, uint32_t seqnum,
  55                            uint16_t msglen);
  56 extern struct msg *msg_dup(struct msg *msg);
  57 extern void msg_print(struct msg *msg); /* XXX debug only */
  58 extern void msg_free(struct msg *msg);
  59 struct msg *msg_read(int fd);
  60 extern int msg_write(int fd, struct msg *msg);
  61
  62 /* For requests, the message sequence number is between MIN_SEQ and
  63    MAX_SEQ. For notifications, the sequence number is 0. */
  64
  65 #define MIN_SEQ          1
  66 #define MAX_SEQ 2147483647
  67
  68 extern void msg_set_seq(struct msg *msg, uint32_t seqnr);
  69 extern uint32_t msg_get_seq(struct msg *msg);
  70
  71 /* -----------------------------------------------------------
  72  * Message fifo queues
  73  * -----------------------------------------------------------
  74  */
  75
  76 /* Message queue structure. */
  77 struct msg_fifo {
  78         unsigned long count;
  79
  80         struct msg *head;
  81         struct msg *tail;
  82 };
  83
  84 /* Prototype for message fifo queues. */
  85 extern struct msg_fifo *msg_fifo_new(void);
  86 extern void msg_fifo_push(struct msg_fifo *, struct msg *msg);
  87 extern struct msg *msg_fifo_pop(struct msg_fifo *fifo);
  88 extern struct msg *msg_fifo_head(struct msg_fifo *fifo);
  89 extern void msg_fifo_flush(struct msg_fifo *fifo);
  90 extern void msg_fifo_free(struct msg_fifo *fifo);
  91
  92 /* -----------------------------------------------------------
  93  * Specific message type and format definitions
  94  * -----------------------------------------------------------
  95  */
  96
  97 /* Messages to OSPF daemon. */
  98 #define MSG_REGISTER_OPAQUETYPE   1
  99 #define MSG_UNREGISTER_OPAQUETYPE 2
 100 #define MSG_REGISTER_EVENT        3
 101 #define MSG_SYNC_LSDB             4
 102 #define MSG_ORIGINATE_REQUEST     5
 103 #define MSG_DELETE_REQUEST        6
 104 #define MSG_SYNC_REACHABLE        7
 105 #define MSG_SYNC_ISM              8
 106 #define MSG_SYNC_NSM              9
 107 #define MSG_SYNC_ROUTER_ID        19
 108
 109 /* Messages from OSPF daemon. */
 110 #define MSG_REPLY                10
 111 #define MSG_READY_NOTIFY         11
 112 #define MSG_LSA_UPDATE_NOTIFY    12
 113 #define MSG_LSA_DELETE_NOTIFY    13
 114 #define MSG_NEW_IF               14
 115 #define MSG_DEL_IF               15
 116 #define MSG_ISM_CHANGE           16
 117 #define MSG_NSM_CHANGE           17
 118 #define MSG_REACHABLE_CHANGE     18
 119 #define MSG_ROUTER_ID_CHANGE     20
 120
 121 struct msg_register_opaque_type {
 122         uint8_t lsatype;
 123         uint8_t opaquetype;
 124         uint8_t pad[2]; /* padding */
 125 };
 126
 127 struct msg_unregister_opaque_type {
 128         uint8_t lsatype;
 129         uint8_t opaquetype;
 130         uint8_t pad[2]; /* padding */
 131 };
 132
 133 /* Power2 is needed to convert LSA types into bit positions,
 134  * see typemask below. Type definition starts at 1, so
 135  * Power2[0] is not used. */
 136
 137
 138 static const uint16_t Power2[] = {
 139         0,       (1 << 0),  (1 << 1),  (1 << 2),  (1 << 3), (1 << 4),
 140         (1 << 5),  (1 << 6),  (1 << 7),  (1 << 8),  (1 << 9), (1 << 10),
 141         (1 << 11), (1 << 12), (1 << 13), (1 << 14), (1 << 15)};
 142
 143 struct lsa_filter_type {
 144         uint16_t typemask; /* bitmask for selecting LSA types (1..16) */
 145         uint8_t origin;    /* selects according to origin. */
 146 #define NON_SELF_ORIGINATED     0
 147 #define SELF_ORIGINATED  (OSPF_LSA_SELF)
 148 #define ANY_ORIGIN 2
 149
 150         uint8_t num_areas; /* number of areas in the filter. */
 151                            /* areas, if any, go here. */
 152 };
 153
 154 struct msg_register_event {
 155         struct lsa_filter_type filter;
 156 };
 157
 158 struct msg_sync_lsdb {
 159         struct lsa_filter_type filter;
 160 };
 161
 162 struct msg_originate_request {
 163         /* Used for LSA type 9 otherwise ignored */
 164         struct in_addr ifaddr;
 165
 166         /* Used for LSA type 10 otherwise ignored */
 167         struct in_addr area_id;
 168
 169         /* LSA header and LSA-specific part */
 170         struct lsa_header data;
 171 };
 172
 173
 174 /* OSPF API MSG Delete Flag. */
 175 #define OSPF_API_DEL_ZERO_LEN_LSA 0x01 /* send withdrawal with no LSA data */
 176
 177 #define IS_DEL_ZERO_LEN_LSA(x) ((x)->flags & OSPF_API_DEL_ZERO_LEN_LSA)
 178
 179 struct msg_delete_request {
 180         struct in_addr addr; /* intf IP for link local, area for type 10,
 181                                 "0.0.0.0" for AS-external */
 182         uint8_t lsa_type;
 183         uint8_t opaque_type;
 184         uint8_t pad;   /* padding */
 185         uint8_t flags; /* delete flags */
 186         uint32_t opaque_id;
 187 };
 188
 189 struct msg_reply {
 190         signed char errcode;
 191 #define OSPF_API_OK                         0
 192 #define OSPF_API_NOSUCHINTERFACE          (-1)
 193 #define OSPF_API_NOSUCHAREA               (-2)
 194 #define OSPF_API_NOSUCHLSA                (-3)
 195 #define OSPF_API_ILLEGALLSATYPE           (-4)
 196 #define OSPF_API_OPAQUETYPEINUSE          (-5)
 197 #define OSPF_API_OPAQUETYPENOTREGISTERED  (-6)
 198 #define OSPF_API_NOTREADY                 (-7)
 199 #define OSPF_API_NOMEMORY                 (-8)
 200 #define OSPF_API_ERROR                    (-9)
 201 #define OSPF_API_UNDEF                   (-10)
 202         uint8_t pad[3]; /* padding to four byte alignment */
 203 };
 204
 205 /* Message to tell client application that it ospf daemon is
 206  * ready to accept opaque LSAs for a given interface or area. */
 207
 208 struct msg_ready_notify {
 209         uint8_t lsa_type;
 210         uint8_t opaque_type;
 211         uint8_t pad[2];      /* padding */
 212         struct in_addr addr; /* interface address or area address */
 213 };
 214
 215 /* These messages have a dynamic length depending on the embodied LSA.
 216    They are aligned to four octets. msg_lsa_change_notify is used for
 217    both LSA update and LSAs delete. */
 218
 219 struct msg_lsa_change_notify {
 220         /* Used for LSA type 9 otherwise ignored */
 221         struct in_addr ifaddr;
 222         /* Area ID. Not valid for AS-External and Opaque11 LSAs. */
 223         struct in_addr area_id;
 224         uint8_t is_self_originated; /* 1 if self originated. */
 225         uint8_t pad[3];
 226         struct lsa_header data;
 227 };
 228
 229 struct msg_new_if {
 230         struct in_addr ifaddr;  /* interface IP address */
 231         struct in_addr area_id; /* area this interface belongs to */
 232 };
 233
 234 struct msg_del_if {
 235         struct in_addr ifaddr; /* interface IP address */
 236 };
 237
 238 struct msg_ism_change {
 239         struct in_addr ifaddr;  /* interface IP address */
 240         struct in_addr area_id; /* area this interface belongs to */
 241         uint8_t status;         /* interface status (up/down) */
 242         uint8_t pad[3];         /* not used */
 243 };
 244
 245 struct msg_nsm_change {
 246         struct in_addr ifaddr;    /* attached interface */
 247         struct in_addr nbraddr;   /* Neighbor interface address */
 248         struct in_addr router_id; /* Router ID of neighbor */
 249         uint8_t status;           /* NSM status */
 250         uint8_t pad[3];
 251 };
 252
 253 struct msg_reachable_change {
 254         uint16_t nadd;
 255         uint16_t nremove;
 256         struct in_addr router_ids[]; /* add followed by remove */
 257 };
 258
 259 struct msg_router_id_change {
 260         struct in_addr router_id; /* this systems router id */
 261 };
 262
 263 /* We make use of a union to define a structure that covers all
 264    possible API messages. This allows us to find out how much memory
 265    needs to be reserved for the largest API message. */
 266 struct apimsg {
 267         struct apimsghdr hdr;
 268         union {
 269                 struct msg_register_opaque_type register_opaque_type;
 270                 struct msg_register_event register_event;
 271                 struct msg_sync_lsdb sync_lsdb;
 272                 struct msg_originate_request originate_request;
 273                 struct msg_delete_request delete_request;
 274                 struct msg_reply reply;
 275                 struct msg_ready_notify ready_notify;
 276                 struct msg_new_if new_if;
 277                 struct msg_del_if del_if;
 278                 struct msg_ism_change ism_change;
 279                 struct msg_nsm_change nsm_change;
 280                 struct msg_lsa_change_notify lsa_change_notify;
 281                 struct msg_reachable_change reachable_change;
 282                 struct msg_router_id_change router_id_change;
 283         } u;
 284 };
 285
 286 #define OSPF_API_MAX_MSG_SIZE (sizeof(struct apimsg) + OSPF_MAX_PACKET_SIZE)
 287
 288 /* -----------------------------------------------------------
 289  * Prototypes for specific messages
 290  * -----------------------------------------------------------
 291  */
 292
 293 /* For debugging only. */
 294 extern void api_opaque_lsa_print(struct ospf_lsa *lsa);
 295
 296 /* Messages sent by client */
 297 extern struct msg *new_msg_register_opaque_type(uint32_t seqnum, uint8_t ltype,
 298                                                 uint8_t otype);
 299 extern struct msg *new_msg_register_event(uint32_t seqnum,
 300                                           struct lsa_filter_type *filter);
 301 extern struct msg *new_msg_sync_lsdb(uint32_t seqnum,
 302                                      struct lsa_filter_type *filter);
 303 extern struct msg *new_msg_originate_request(uint32_t seqnum,
 304                                              struct in_addr ifaddr,
 305                                              struct in_addr area_id,
 306                                              struct lsa_header *data);
 307 extern struct msg *new_msg_delete_request(uint32_t seqnum, struct in_addr addr,
 308                                           uint8_t lsa_type, uint8_t opaque_type,
 309                                           uint32_t opaque_id, uint8_t flags);
 310
 311 /* Messages sent by OSPF daemon */
 312 extern struct msg *new_msg_reply(uint32_t seqnum, uint8_t rc);
 313
 314 extern struct msg *new_msg_ready_notify(uint32_t seqnr, uint8_t lsa_type,
 315                                         uint8_t opaque_type,
 316                                         struct in_addr addr);
 317
 318 extern struct msg *new_msg_new_if(uint32_t seqnr, struct in_addr ifaddr,
 319                                   struct in_addr area);
 320
 321 extern struct msg *new_msg_del_if(uint32_t seqnr, struct in_addr ifaddr);
 322
 323 extern struct msg *new_msg_ism_change(uint32_t seqnr, struct in_addr ifaddr,
 324                                       struct in_addr area, uint8_t status);
 325
 326 extern struct msg *new_msg_nsm_change(uint32_t seqnr, struct in_addr ifaddr,
 327                                       struct in_addr nbraddr,
 328                                       struct in_addr router_id, uint8_t status);
 329
 330 /* msgtype is MSG_LSA_UPDATE_NOTIFY or MSG_LSA_DELETE_NOTIFY */
 331 extern struct msg *new_msg_lsa_change_notify(uint8_t msgtype, uint32_t seqnum,
 332                                              struct in_addr ifaddr,
 333                                              struct in_addr area_id,
 334                                              uint8_t is_self_originated,
 335                                              struct lsa_header *data);
 336
 337 extern struct msg *new_msg_reachable_change(uint32_t seqnum, uint16_t nadd,
 338                                             struct in_addr *add,
 339                                             uint16_t nremove,
 340                                             struct in_addr *remove);
 341
 342 extern struct msg *new_msg_router_id_change(uint32_t seqnr,
 343                                             struct in_addr router_id);
 344 /* string printing functions */
 345 extern const char *ospf_api_errname(int errcode);
 346 extern const char *ospf_api_typename(int msgtype);
 347
 348 #endif /* _OSPF_API_H */