includes/failover.h

   1 /* failover.h
   2
   3    Definitions for address trees... */
   4
   5 /*
   6  * Copyright (c) 2004-2017 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 2000-2003 by Internet Software Consortium
   8  *
   9  * This Source Code Form is subject to the terms of the Mozilla Public
  10  * License, v. 2.0. If a copy of the MPL was not distributed with this
  11  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  15  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  19  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20  *
  21  *   Internet Systems Consortium, Inc.
  22  *   950 Charter Street
  23  *   Redwood City, CA 94063
  24  *   <info@isc.org>
  25  *   https://www.isc.org/
  26  *
  27  */
  28
  29 #if defined (FAILOVER_PROTOCOL)
  30 struct failover_option_info {
  31         int code;
  32         const char *name;
  33         enum { FT_UINT8, FT_IPADDR, FT_UINT32, FT_BYTES, FT_TEXT_OR_BYTES,
  34                FT_DDNS, FT_DDNS1, FT_UINT16, FT_TEXT,
  35                FT_UNDEF, FT_DIGEST } type;
  36         int num_present;
  37         int offset;
  38         u_int32_t bit;
  39 };
  40
  41 typedef struct {
  42         unsigned count;
  43         u_int8_t *data;
  44 } failover_option_t;
  45
  46 /* Failover configuration defaults. */
  47 #ifndef  DEFAULT_MAX_BALANCE_TIME
  48 # define DEFAULT_MAX_BALANCE_TIME       3600
  49 #endif
  50
  51 #ifndef  DEFAULT_MIN_BALANCE_TIME
  52 # define DEFAULT_MIN_BALANCE_TIME       60
  53 #endif
  54
  55 #ifndef  DEFAULT_MAX_LEASE_MISBALANCE
  56 # define DEFAULT_MAX_LEASE_MISBALANCE   15
  57 #endif
  58
  59 #ifndef  DEFAULT_MAX_LEASE_OWNERSHIP
  60 # define DEFAULT_MAX_LEASE_OWNERSHIP    10
  61 #endif
  62
  63 #ifndef  DEFAULT_MAX_FLYING_UPDATES
  64 # define DEFAULT_MAX_FLYING_UPDATES     100
  65 #endif
  66
  67 #ifndef  DEFAULT_MAX_RESPONSE_DELAY
  68 # define DEFAULT_MAX_RESPONSE_DELAY     20
  69 #endif
  70
  71 /*
  72  * IANA has assigned ports 647 ("dhcp-failover") and 847 ("dhcp-failover2").
  73  * Of these, only port 647 is mentioned in the -12 draft revision.  We're not
  74  * sure if they are supposed to indicate primary and secondary?  No matter,
  75  * we'll stick to the -12 draft revision level.
  76  */
  77 #ifndef  DEFAULT_FAILOVER_PORT
  78 # define DEFAULT_FAILOVER_PORT          647
  79 #endif
  80
  81 #define FM_OFFSET(x) (long)(&(((failover_message_t *)0) -> x))
  82
  83 /* All of the below definitions are mandated by draft-ietf-dhc-failover-12.
  84  * The Sections referenced are Sections within that document of that
  85  * version, and may be different in other documents of other versions.
  86  */
  87
  88 /* Failover message options from Section 12: */
  89 #define FTO_ADDRESSES_TRANSFERRED       1
  90 #define FTB_ADDRESSES_TRANSFERRED               0x00000002
  91 #define FTO_ASSIGNED_IP_ADDRESS         2
  92 #define FTB_ASSIGNED_IP_ADDRESS                 0x00000004
  93 #define FTO_BINDING_STATUS              3
  94 #define FTB_BINDING_STATUS                      0x00000008
  95 #define FTO_CLIENT_IDENTIFIER           4
  96 #define FTB_CLIENT_IDENTIFIER                   0x00000010
  97 #define FTO_CHADDR                      5
  98 #define FTB_CHADDR                              0x00000020
  99 #define FTO_CLTT                        6
 100 #define FTB_CLTT                                0x00000040
 101 #define FTO_REPLY_OPTIONS               7
 102 #define FTB_REPLY_OPTIONS                       0x00000080
 103 #define FTO_REQUEST_OPTIONS             8
 104 #define FTB_REQUEST_OPTIONS                     0x00000100
 105 #define FTO_DDNS                        9
 106 #define FTB_DDNS                                0x00000200
 107 #define FTO_DELAYED_SERVICE             10
 108 #define FTB_DELAYED_SERVICE                     0x00000400
 109 #define FTO_HBA                         11
 110 #define FTB_HBA                                 0x00000800
 111 #define FTO_IP_FLAGS                    12
 112 #define FTB_IP_FLAGS                            0x00001000
 113 #define FTO_LEASE_EXPIRY                13
 114 #define FTB_LEASE_EXPIRY                        0x00002000
 115 #define FTO_MAX_UNACKED                 14
 116 #define FTB_MAX_UNACKED                         0x00004000
 117 #define FTO_MCLT                        15
 118 #define FTB_MCLT                                0x00008000
 119 #define FTO_MESSAGE                     16
 120 #define FTB_MESSAGE                             0x00010000
 121 #define FTO_MESSAGE_DIGEST              17
 122 #define FTB_MESSAGE_DIGEST                      0x00020000
 123 #define FTO_POTENTIAL_EXPIRY            18
 124 #define FTB_POTENTIAL_EXPIRY                    0x00040000
 125 #define FTO_RECEIVE_TIMER               19
 126 #define FTB_RECEIVE_TIMER                       0x00080000
 127 #define FTO_PROTOCOL_VERSION            20
 128 #define FTB_PROTOCOL_VERSION                    0x00100000
 129 #define FTO_REJECT_REASON               21
 130 #define FTB_REJECT_REASON                       0x00200000
 131 #define FTO_RELATIONSHIP_NAME           22
 132 #define FTB_RELATIONSHIP_NAME                   0x00400000
 133 #define FTO_SERVER_FLAGS                23
 134 #define FTB_SERVER_FLAGS                        0x00800000
 135 #define FTO_SERVER_STATE                24
 136 #define FTB_SERVER_STATE                        0x01000000
 137 #define FTO_STOS                        25
 138 #define FTB_STOS                                0x02000000
 139 #define FTO_TLS_REPLY                   26
 140 #define FTB_TLS_REPLY                           0x04000000
 141 #define FTO_TLS_REQUEST                 27
 142 #define FTB_TLS_REQUEST                         0x08000000
 143 #define FTO_VENDOR_CLASS                28
 144 #define FTB_VENDOR_CLASS                        0x10000000
 145 #define FTO_VENDOR_OPTIONS              29
 146 #define FTB_VENDOR_OPTIONS                      0x20000000
 147
 148 #define FTO_MAX                         FTO_VENDOR_OPTIONS
 149
 150 /* Failover protocol message types from Section 6.1: */
 151 #define FTM_POOLREQ             1
 152 #define FTM_POOLRESP            2
 153 #define FTM_BNDUPD              3
 154 #define FTM_BNDACK              4
 155 #define FTM_CONNECT             5
 156 #define FTM_CONNECTACK          6
 157 #define FTM_UPDREQALL           7
 158 #define FTM_UPDDONE             8
 159 #define FTM_UPDREQ              9
 160 #define FTM_STATE               10
 161 #define FTM_CONTACT             11
 162 #define FTM_DISCONNECT          12
 163
 164 #define FTM_MAX                 FTM_DISCONNECT
 165
 166 /* Reject reasons from Section 12.21: */
 167 #define FTR_ILLEGAL_IP_ADDR     1
 168 #define FTR_FATAL_CONFLICT      2
 169 #define FTR_MISSING_BINDINFO    3
 170 #define FTR_TIMEMISMATCH        4
 171 #define FTR_INVALID_MCLT        5
 172 #define FTR_MISC_REJECT         6
 173 #define FTR_DUP_CONNECTION      7
 174 #define FTR_INVALID_PARTNER     8
 175 #define FTR_TLS_UNSUPPORTED     9
 176 #define FTR_TLS_UNCONFIGURED    10
 177 #define FTR_TLS_REQUIRED        11
 178 #define FTR_DIGEST_UNSUPPORTED  12
 179 #define FTR_DIGEST_UNCONFIGURED 13
 180 #define FTR_VERSION_MISMATCH    14
 181 #define FTR_OUTDATED_BIND_INFO  15
 182 #define FTR_LESS_CRIT_BIND_INFO 16
 183 #define FTR_NO_TRAFFIC          17
 184 #define FTR_HBA_CONFLICT        18
 185 #define FTR_IP_NOT_RESERVED     19
 186 #define FTR_IP_DIGEST_FAILURE   20
 187 #define FTR_IP_MISSING_DIGEST   21
 188 #define FTR_UNKNOWN             254
 189
 190 /* Message size limitations defined in Section 6.1: */
 191 #define DHCP_FAILOVER_MIN_MESSAGE_SIZE    12
 192 #define DHCP_FAILOVER_MAX_MESSAGE_SIZE  2048
 193
 194 /* Failover server flags from Section 12.23: */
 195 #define FTF_SERVER_STARTUP      1
 196
 197 /* DDNS flags from Section 12.9.  These are really their names. */
 198 #define FTF_DDNS_C              0x0001
 199 #define FTF_DDNS_A              0x0002
 200 #define FTF_DDNS_D              0x0004
 201 #define FTF_DDNS_P              0x0008
 202
 203 /* FTO_IP_FLAGS contents from Section 12.12: */
 204 #define FTF_IP_FLAG_RESERVE     0x0001
 205 #define FTF_IP_FLAG_BOOTP       0x0002
 206
 207 /* FTO_MESSAGE_DIGEST Type Codes from Section 12.17: */
 208 #define FTT_MESSAGE_DIGEST_HMAC_MD5     0x01
 209
 210 typedef struct failover_message {
 211         int refcnt;
 212         struct failover_message *next;
 213
 214         int options_present;
 215
 216         u_int32_t time;
 217         u_int32_t xid;
 218         u_int8_t type;
 219
 220         /* One-byte options. */
 221         u_int8_t binding_status;
 222         u_int8_t delayed_service;
 223         u_int8_t protocol_version;
 224         u_int8_t reject_reason;
 225         u_int8_t server_flags;
 226         u_int8_t server_state;
 227         u_int8_t tls_reply;
 228         u_int8_t tls_request;
 229
 230         /* Two-byte options. */
 231         u_int16_t ip_flags;
 232
 233         /* Four-byte options. */
 234         u_int32_t addresses_transferred;
 235         u_int32_t assigned_addr;
 236         u_int32_t cltt;
 237         u_int32_t expiry;
 238         u_int32_t max_unacked;
 239         u_int32_t mclt;
 240         u_int32_t potential_expiry;
 241         u_int32_t receive_timer;
 242         u_int32_t stos;
 243
 244         /* Arbitrary field options. */
 245         failover_option_t chaddr;
 246         failover_option_t client_identifier;
 247         failover_option_t hba;
 248         failover_option_t message;
 249         failover_option_t message_digest;
 250         failover_option_t relationship_name;
 251         failover_option_t reply_options;
 252         failover_option_t request_options;
 253         failover_option_t vendor_class;
 254         failover_option_t vendor_options;
 255
 256         /* Special contents options. */
 257         ddns_fqdn_t ddns;
 258 } failover_message_t;
 259
 260 typedef struct {
 261         OMAPI_OBJECT_PREAMBLE;
 262         struct option_cache *peer_address;
 263         unsigned peer_port;
 264         int options_present;
 265         enum dhcp_flink_state {
 266                 dhcp_flink_start,
 267                 dhcp_flink_message_length_wait,
 268                 dhcp_flink_message_wait,
 269                 dhcp_flink_disconnected,
 270                 dhcp_flink_state_max
 271         } state;
 272         failover_message_t *imsg;
 273         struct _dhcp_failover_state *state_object;
 274         u_int16_t imsg_len;
 275         unsigned imsg_count;
 276         u_int8_t imsg_payoff; /* Pay*load* offset. :') */
 277         u_int32_t xid;
 278 } dhcp_failover_link_t;
 279
 280 typedef struct _dhcp_failover_listener {
 281         OMAPI_OBJECT_PREAMBLE;
 282         struct _dhcp_failover_listener *next;
 283         omapi_addr_t address;
 284 } dhcp_failover_listener_t;
 285 #endif /* FAILOVER_PROTOCOL */
 286
 287 /* A failover peer's running state. */
 288 enum failover_state {
 289         unknown_state                   =  0, /* XXX: Not a standard state. */
 290         startup                         =  1,
 291         normal                          =  2,
 292         communications_interrupted      =  3,
 293         partner_down                    =  4,
 294         potential_conflict              =  5,
 295         recover                         =  6,
 296         paused                          =  7,
 297         shut_down                       =  8,
 298         recover_done                    =  9,
 299         resolution_interrupted          = 10,
 300         conflict_done                   = 11,
 301
 302         /* Draft revision 12 of the failover protocol documents a RECOVER-WAIT
 303          * state, but does not enumerate its value in the section 12.24
 304          * table.  ISC DHCP 3.0.x used value 254 even though the state was
 305          * not documented at all.  For the time being, we will continue to use
 306          * this value.
 307          */
 308         recover_wait                    = 254
 309 };
 310
 311 /* Service states are simplifications of failover states, particularly
 312    useful because the startup state isn't actually implementable as a
 313    separate failover state without maintaining a state stack. */
 314
 315 enum service_state {
 316         unknown_service_state,
 317         cooperating,
 318         not_cooperating,
 319         service_partner_down,
 320         not_responding,
 321         service_startup
 322 };
 323
 324 #if defined (FAILOVER_PROTOCOL)
 325 typedef struct _dhcp_failover_config {
 326         struct option_cache *address;
 327         int port;
 328         u_int32_t max_flying_updates;
 329         enum failover_state state;
 330         TIME stos;
 331         u_int32_t max_response_delay;
 332 } dhcp_failover_config_t;
 333
 334 typedef struct _dhcp_failover_state {
 335         OMAPI_OBJECT_PREAMBLE;
 336         struct _dhcp_failover_state *next;
 337         char *name;                     /* Name of this failover instance. */
 338         dhcp_failover_config_t me;      /* My configuration. */
 339         dhcp_failover_config_t partner; /* Partner's configuration. */
 340         enum failover_state saved_state; /* Saved state during startup. */
 341         struct data_string server_identifier; /* Server identifier (IP addr) */
 342         u_int32_t mclt;
 343
 344         u_int8_t *hba;  /* Hash bucket array for load balancing. */
 345         int load_balance_max_secs;
 346
 347         u_int32_t max_lease_misbalance, max_lease_ownership;
 348         u_int32_t max_balance, min_balance;
 349         TIME last_balance, sched_balance;
 350
 351         u_int32_t auto_partner_down;
 352
 353         enum service_state service_state;
 354         const char *nrr;        /* Printable reason why we're in the
 355                                    not_responding service state (empty
 356                                    string if we are responding. */
 357
 358         dhcp_failover_link_t *link_to_peer;     /* Currently-established link
 359                                                    to peer. */
 360
 361         enum {
 362                 primary, secondary
 363         } i_am;         /* We are primary or secondary in this relationship. */
 364
 365         TIME last_packet_sent;          /* Timestamp on last packet we sent. */
 366         TIME last_timestamp_received;   /* The last timestamp we sent that
 367                                            has been returned by our partner. */
 368         TIME skew;      /* The skew between our clock and our partner's. */
 369         struct lease *update_queue_head; /* List of leases we haven't sent
 370                                             to peer. */
 371         struct lease *update_queue_tail;
 372
 373         struct lease *ack_queue_head;   /* List of lease updates the peer
 374                                            hasn't yet acked. */
 375         struct lease *ack_queue_tail;
 376
 377         struct lease *send_update_done; /* When we get a BNDACK for this
 378                                            lease, send an UPDDONE message. */
 379         int cur_unacked_updates;        /* Number of updates we've sent
 380                                            that have not yet been acked. */
 381
 382                                         /* List of messages which we haven't
 383                                            acked yet. */
 384         failover_message_t *toack_queue_head;
 385         failover_message_t *toack_queue_tail;
 386         int pending_acks;               /* Number of messages in the toack
 387                                            queue. */
 388         int pool_count;                 /* Number of pools referencing this
 389                                            failover state object. */
 390         int curUPD;                     /* If an UPDREQ* message is in motion,
 391                                            this value indicates which one. */
 392         u_int32_t updxid;               /* XID of UPDREQ* message in action. */
 393 } dhcp_failover_state_t;
 394
 395 extern int check_secs_byte_order; /* check byte order of secs field when true */
 396
 397 #define DHCP_FAILOVER_VERSION           1
 398 #endif /* FAILOVER_PROTOCOL */