contrib/isc-dhcp/includes/failover.h

   1 /* failover.h
   2
   3    Definitions for address trees... */
   4
   5 /*
   6  * Copyright (c) 2000-2001 Internet Software Consortium.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of The Internet Software Consortium nor the names
  19  *    of its contributors may be used to endorse or promote products derived
  20  *    from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
  23  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  24  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  25  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  26  * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
  27  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  29  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  30  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  31  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  32  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  33  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * This software has been written for the Internet Software Consortium
  37  * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
  38  * To learn more about the Internet Software Consortium, see
  39  * ``http://www.isc.org/''.  To learn more about Vixie Enterprises,
  40  * see ``http://www.vix.com''.   To learn more about Nominum, Inc., see
  41  * ``http://www.nominum.com''.
  42  */
  43
  44 #if defined (FAILOVER_PROTOCOL)
  45 struct failover_option_info {
  46         int code;
  47         const char *name;
  48         enum { FT_UINT8, FT_IPADDR, FT_UINT32, FT_BYTES, FT_TEXT_OR_BYTES,
  49                FT_DDNS, FT_DDNS1, FT_UINT16, FT_TEXT,
  50                FT_UNDEF, FT_DIGEST } type;
  51         int num_present;
  52         int offset;
  53         u_int32_t bit;
  54 };
  55
  56 typedef struct {
  57         unsigned count;
  58         u_int8_t *data;
  59 } failover_option_t;
  60
  61 #define FM_OFFSET(x) (long)(&(((failover_message_t *)0) -> x))
  62
  63 /* Failover message options: */
  64 #define FTO_BINDING_STATUS              1
  65 #define FTB_BINDING_STATUS                      0x00000002
  66 #define FTO_ASSIGNED_IP_ADDRESS         2
  67 #define FTB_ASSIGNED_IP_ADDRESS                 0x00000004
  68 #define FTO_SERVER_ADDR                 3
  69 #define FTB_SERVER_ADDR                         0x00000008
  70 #define FTO_ADDRESSES_TRANSFERRED       4
  71 #define FTB_ADDRESSES_TRANSFERRED               0x00000010
  72 #define FTO_CLIENT_IDENTIFIER           5
  73 #define FTB_CLIENT_IDENTIFIER                   0x00000020
  74 #define FTO_CHADDR                      6
  75 #define FTB_CHADDR                              0x00000040
  76 #define FTO_DDNS                        7
  77 #define FTB_DDNS                                0x00000080
  78 #define FTO_REJECT_REASON               8
  79 #define FTB_REJECT_REASON                       0x00000100
  80 #define FTO_MESSAGE                     9
  81 #define FTB_MESSAGE                             0x00000200
  82 #define FTO_MCLT                        10
  83 #define FTB_MCLT                                0x00000400
  84 #define FTO_VENDOR_CLASS                11
  85 #define FTB_VENDOR_CLASS                        0x00000800
  86 #define FTO_LEASE_EXPIRY                13
  87 #define FTB_LEASE_EXPIRY                        0x00002000
  88 #define FTO_POTENTIAL_EXPIRY            14
  89 #define FTB_POTENTIAL_EXPIRY                    0x00004000
  90 #define FTO_GRACE_EXPIRY                15
  91 #define FTB_GRACE_EXPIRY                        0x00008000
  92 #define FTO_CLTT                        16
  93 #define FTB_CLTT                                0x00010000
  94 #define FTO_STOS                        17
  95 #define FTB_STOS                                0x00020000
  96 #define FTO_SERVER_STATE                18
  97 #define FTB_SERVER_STATE                        0x00040000
  98 #define FTO_SERVER_FLAGS                19
  99 #define FTB_SERVER_FLAGS                        0x00080000
 100 #define FTO_VENDOR_OPTIONS              20
 101 #define FTB_VENDOR_OPTIONS                      0x00100000
 102 #define FTO_MAX_UNACKED                 21
 103 #define FTB_MAX_UNACKED                         0x00200000
 104 #define FTO_RECEIVE_TIMER               23
 105 #define FTB_RECEIVE_TIMER                       0x00800000
 106 #define FTO_HBA                         24
 107 #define FTB_HBA                                 0x01000000
 108 #define FTO_MESSAGE_DIGEST              25
 109 #define FTB_MESSAGE_DIGEST                      0x02000000
 110 #define FTO_PROTOCOL_VERSION            26
 111 #define FTB_PROTOCOL_VERSION                    0x04000000
 112 #define FTO_TLS_REQUEST                 27
 113 #define FTB_TLS_REQUEST                         0x08000000
 114 #define FTO_TLS_REPLY                   28
 115 #define FTB_TLS_REPLY                           0x10000000
 116 #define FTO_REQUEST_OPTIONS             29
 117 #define FTB_REQUEST_OPTIONS                     0x20000000
 118 #define FTO_REPLY_OPTIONS               30
 119 #define FTB_REPLY_OPTIONS                       0x40000000
 120 #define FTO_MAX                         FTO_REPLY_OPTIONS
 121
 122 /* Failover protocol message types: */
 123 #define FTM_POOLREQ             1
 124 #define FTM_POOLRESP            2
 125 #define FTM_BNDUPD              3
 126 #define FTM_BNDACK              4
 127 #define FTM_CONNECT             5
 128 #define FTM_CONNECTACK          6
 129 #define FTM_UPDREQ              7
 130 #define FTM_UPDDONE             8
 131 #define FTM_UPDREQALL           9
 132 #define FTM_STATE               10
 133 #define FTM_CONTACT             11
 134 #define FTM_DISCONNECT          12
 135
 136 /* Reject reasons: */
 137
 138 #define FTR_ILLEGAL_IP_ADDR     1
 139 #define FTR_FATAL_CONFLICT      2
 140 #define FTR_MISSING_BINDINFO    3
 141 #define FTR_TIMEMISMATCH        4
 142 #define FTR_INVALID_MCLT        5
 143 #define FTR_MISC_REJECT         6
 144 #define FTR_DUP_CONNECTION      7
 145 #define FTR_INVALID_PARTNER     8
 146 #define FTR_TLS_UNSUPPORTED     9
 147 #define FTR_TLS_UNCONFIGURED    10
 148 #define FTR_TLS_REQUIRED        11
 149 #define FTR_DIGEST_UNSUPPORTED  12
 150 #define FTR_DIGEST_UNCONFIGURED 13
 151 #define FTR_VERSION_MISMATCH    14
 152 #define FTR_MISSING_BIND_INFO   15
 153 #define FTR_OUTDATED_BIND_INFO  16
 154 #define FTR_LESS_CRIT_BIND_INFO 17
 155 #define FTR_NO_TRAFFIC          18
 156 #define FTR_HBA_CONFLICT        19
 157 #define FTR_UNKNOWN             254
 158
 159 #define DHCP_FAILOVER_MAX_MESSAGE_SIZE  2048
 160
 161 /* Failover server flags. */
 162 #define FTF_STARTUP     1
 163
 164 typedef struct failover_message {
 165         int refcnt;
 166         struct failover_message *next;
 167
 168         u_int8_t type;
 169
 170         u_int8_t binding_status;
 171         u_int8_t protocol_version;
 172         u_int8_t reject_reason;
 173         u_int8_t server_flags;
 174         u_int8_t server_state;
 175         u_int8_t tls_reply;
 176         u_int8_t tls_request;
 177         u_int32_t stos;
 178         u_int32_t time;
 179         u_int32_t xid;
 180         u_int32_t addresses_transferred;
 181         u_int32_t assigned_addr;
 182         u_int32_t client_ltt;
 183         u_int32_t expiry;
 184         u_int32_t grace_expiry;
 185         u_int32_t max_unacked;
 186         u_int32_t mclt;
 187         u_int32_t potential_expiry;
 188         u_int32_t receive_timer;
 189         u_int32_t server_addr;
 190         failover_option_t chaddr;
 191         failover_option_t client_identifier;
 192         failover_option_t hba;
 193         failover_option_t message;
 194         failover_option_t reply_options;
 195         failover_option_t request_options;
 196         ddns_fqdn_t ddns;
 197         failover_option_t vendor_class;
 198         failover_option_t vendor_options;
 199
 200         int options_present;
 201 } failover_message_t;
 202
 203 typedef struct {
 204         OMAPI_OBJECT_PREAMBLE;
 205         struct option_cache *peer_address;
 206         unsigned peer_port;
 207         int options_present;
 208         enum dhcp_flink_state {
 209                 dhcp_flink_start,
 210                 dhcp_flink_message_length_wait,
 211                 dhcp_flink_message_wait,
 212                 dhcp_flink_disconnected,
 213                 dhcp_flink_state_max
 214         } state;
 215         failover_message_t *imsg;
 216         struct _dhcp_failover_state *state_object;
 217         u_int16_t imsg_len;
 218         unsigned imsg_count;
 219         u_int8_t imsg_payoff; /* Pay*load* offset. :') */
 220         u_int32_t xid;
 221 } dhcp_failover_link_t;
 222
 223 typedef struct _dhcp_failover_listener {
 224         OMAPI_OBJECT_PREAMBLE;
 225         struct _dhcp_failover_listener *next;
 226         omapi_addr_t address;
 227 } dhcp_failover_listener_t;
 228 #endif /* FAILOVER_PROTOCOL */
 229
 230 /* A failover peer. */
 231 enum failover_state {
 232         unknown_state,
 233         partner_down,
 234         normal,
 235         communications_interrupted,
 236         resolution_interrupted,
 237         potential_conflict,
 238         recover,
 239         recover_done,
 240         shut_down,
 241         paused,
 242         startup,
 243         recover_wait
 244 };
 245
 246 /* Service states are simplifications of failover states, particularly
 247    useful because the startup state isn't actually implementable as a
 248    seperate failover state without maintaining a state stack. */
 249
 250 enum service_state {
 251         unknown_service_state,
 252         cooperating,
 253         not_cooperating,
 254         service_partner_down,
 255         not_responding,
 256         service_startup
 257 };
 258
 259 #if defined (FAILOVER_PROTOCOL)
 260 typedef struct _dhcp_failover_config {
 261         struct option_cache *address;
 262         int port;
 263         u_int32_t max_flying_updates;
 264         enum failover_state state;
 265         TIME stos;
 266         u_int32_t max_response_delay;
 267 } dhcp_failover_config_t;
 268
 269 typedef struct _dhcp_failover_state {
 270         OMAPI_OBJECT_PREAMBLE;
 271         struct _dhcp_failover_state *next;
 272         char *name;                     /* Name of this failover instance. */
 273         dhcp_failover_config_t me;      /* My configuration. */
 274         dhcp_failover_config_t partner; /* Partner's configuration. */
 275         enum failover_state saved_state; /* Saved state during startup. */
 276         struct data_string server_identifier; /* Server identifier (IP addr) */
 277         u_int32_t mclt;
 278
 279         u_int8_t *hba;  /* Hash bucket array for load balancing. */
 280         int load_balance_max_secs;
 281
 282         enum service_state service_state;
 283         const char *nrr;        /* Printable reason why we're in the
 284                                    not_responding service state (empty
 285                                    string if we are responding. */
 286
 287         dhcp_failover_link_t *link_to_peer;     /* Currently-established link
 288                                                    to peer. */
 289
 290         enum {
 291                 primary, secondary
 292         } i_am;         /* We are primary or secondary in this relationship. */
 293
 294         TIME last_packet_sent;          /* Timestamp on last packet we sent. */
 295         TIME last_timestamp_received;   /* The last timestamp we sent that
 296                                            has been returned by our partner. */
 297         TIME skew;      /* The skew between our clock and our partner's. */
 298         struct lease *update_queue_head; /* List of leases we haven't sent
 299                                             to peer. */
 300         struct lease *update_queue_tail;
 301
 302         struct lease *ack_queue_head;   /* List of lease updates the peer
 303                                            hasn't yet acked. */
 304         struct lease *ack_queue_tail;
 305
 306         struct lease *send_update_done; /* When we get a BNDACK for this
 307                                            lease, send an UPDDONE message. */
 308         int cur_unacked_updates;        /* Number of updates we've sent
 309                                            that have not yet been acked. */
 310
 311                                         /* List of messages which we haven't
 312                                            acked yet. */
 313         failover_message_t *toack_queue_head;
 314         failover_message_t *toack_queue_tail;
 315         int pending_acks;               /* Number of messages in the toack
 316                                            queue. */
 317         int pool_count;                 /* Number of pools referencing this
 318                                            failover state object. */
 319 } dhcp_failover_state_t;
 320
 321 #define DHCP_FAILOVER_VERSION           1
 322 #endif /* FAILOVER_PROTOCOL */