dist/dhcp/includes/tree.h

   1 /* tree.h
   2
   3    Definitions for address trees... */
   4
   5 /*
   6  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 1996-2003 by Internet Software Consortium
   8  *
   9  * Permission to use, copy, modify, and distribute this software for any
  10  * purpose with or without fee is hereby granted, provided that the above
  11  * copyright notice and this permission notice appear in all copies.
  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  *   http://www.isc.org/
  26  *
  27  * This software has been written for Internet Systems Consortium
  28  * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
  29  * To learn more about Internet Systems Consortium, see
  30  * ``http://www.isc.org/''.  To learn more about Vixie Enterprises,
  31  * see ``http://www.vix.com''.   To learn more about Nominum, Inc., see
  32  * ``http://www.nominum.com''.
  33  */
  34
  35 /* A pair of pointers, suitable for making a linked list. */
  36 typedef struct _pair {
  37         caddr_t car;
  38         struct _pair *cdr;
  39 } *pair;
  40
  41 struct option_chain_head {
  42         int refcnt;
  43         pair first;
  44 };
  45
  46 struct enumeration_value {
  47         const char *name;
  48         u_int8_t value;
  49 };
  50
  51 struct enumeration {
  52         struct enumeration *next;
  53         const char *name;
  54         struct enumeration_value *values;
  55 };
  56
  57 /* Tree node types... */
  58 #define TREE_CONCAT             1
  59 #define TREE_HOST_LOOKUP        2
  60 #define TREE_CONST              3
  61 #define TREE_LIMIT              4
  62 #define TREE_DATA_EXPR          5
  63
  64 /* A data buffer with a reference count. */
  65 struct buffer {
  66         int refcnt;
  67         unsigned char data [1];
  68 };
  69
  70 /* XXX The mechanism by which data strings are returned is currently
  71    XXX broken: rather than returning an ephemeral pointer, we create
  72    XXX a reference to the data in the caller's space, which the caller
  73    XXX then has to dereference - instead, the reference should be
  74    XXX ephemeral by default and be made a persistent reference explicitly. */
  75 /* XXX on the other hand, it seems to work pretty nicely, so maybe the
  76    XXX above comment is meshuggenah. */
  77
  78 /* A string of data bytes, possibly accompanied by a larger buffer. */
  79 struct data_string {
  80         struct buffer *buffer;
  81         const unsigned char *data;
  82         unsigned len;   /* Does not include NUL terminator, if any. */
  83         int terminated;
  84 };
  85
  86 enum expression_context {
  87         context_any, /* indefinite */
  88         context_boolean,
  89         context_data,
  90         context_numeric,
  91         context_dns,
  92         context_data_or_numeric, /* indefinite */
  93         context_function
  94 };
  95
  96 struct fundef {
  97         int refcnt;
  98         struct string_list *args;
  99         struct executable_statement *statements;
 100 };
 101
 102 struct binding_value {
 103         int refcnt;
 104         enum {
 105                 binding_boolean,
 106                 binding_data,
 107                 binding_numeric,
 108                 binding_dns,
 109                 binding_function
 110         } type;
 111         union value {
 112                 struct data_string data;
 113                 unsigned long intval;
 114                 int boolean;
 115 #if defined (NSUPDATE)
 116                 ns_updrec *dns;
 117 #endif
 118                 struct fundef *fundef;
 119                 struct binding_value *bv;
 120         } value;
 121 };
 122
 123 struct binding {
 124         struct binding *next;
 125         char *name;
 126         struct binding_value *value;
 127 };
 128
 129 struct binding_scope {
 130         int refcnt;
 131         struct binding_scope *outer;
 132         struct binding *bindings;
 133 };
 134
 135 /* Expression tree structure. */
 136
 137 enum expr_op {
 138         expr_none,
 139         expr_match,
 140         expr_check,
 141         expr_equal,
 142         expr_substring,
 143         expr_suffix,
 144         expr_concat,
 145         expr_host_lookup,
 146         expr_and,
 147         expr_or,
 148         expr_not,
 149         expr_option,
 150         expr_hardware,
 151         expr_packet,
 152         expr_const_data,
 153         expr_extract_int8,
 154         expr_extract_int16,
 155         expr_extract_int32,
 156         expr_encode_int8,
 157         expr_encode_int16,
 158         expr_encode_int32,
 159         expr_const_int,
 160         expr_exists,
 161         expr_encapsulate,
 162         expr_known,
 163         expr_reverse,
 164         expr_leased_address,
 165         expr_binary_to_ascii,
 166         expr_config_option,
 167         expr_host_decl_name,
 168         expr_pick_first_value,
 169         expr_lease_time,
 170         expr_dns_transaction,
 171         expr_static,
 172         expr_ns_add,
 173         expr_ns_delete,
 174         expr_ns_exists,
 175         expr_ns_not_exists,
 176         expr_not_equal,
 177         expr_null,
 178         expr_variable_exists,
 179         expr_variable_reference,
 180         expr_filename,
 181         expr_sname,
 182         expr_arg,
 183         expr_funcall,
 184         expr_function,
 185         expr_add,
 186         expr_subtract,
 187         expr_multiply,
 188         expr_divide,
 189         expr_remainder,
 190         expr_binary_and,
 191         expr_binary_or,
 192         expr_binary_xor,
 193         expr_client_state
 194 };
 195
 196 struct expression {
 197         int refcnt;
 198         enum expr_op op;
 199         union {
 200                 struct {
 201                         struct expression *expr;
 202                         struct expression *offset;
 203                         struct expression *len;
 204                 } substring;
 205                 struct expression *equal [2];
 206                 struct expression *and [2];
 207                 struct expression *or [2];
 208                 struct expression *not;
 209                 struct expression *add;
 210                 struct expression *subtract;
 211                 struct expression *multiply;
 212                 struct expression *divide;
 213                 struct expression *remainder;
 214                 struct collection *check;
 215                 struct {
 216                         struct expression *expr;
 217                         struct expression *len;
 218                 } suffix;
 219                 struct option *option;
 220                 struct option *config_option;
 221                 struct {
 222                         struct expression *offset;
 223                         struct expression *len;
 224                 } packet;
 225                 struct data_string const_data;
 226                 struct expression *extract_int;
 227                 struct expression *encode_int;
 228                 unsigned long const_int;
 229                 struct expression *concat [2];
 230                 struct dns_host_entry *host_lookup;
 231                 struct option *exists;
 232                 struct data_string encapsulate;
 233                 struct {
 234                         struct expression *base;
 235                         struct expression *width;
 236                         struct expression *seperator;
 237                         struct expression *buffer;
 238                 } b2a;
 239                 struct {
 240                         struct expression *width;
 241                         struct expression *buffer;
 242                 } reverse;
 243                 struct {
 244                         struct expression *car;
 245                         struct expression *cdr;
 246                 } pick_first_value;
 247                 struct {
 248                         struct expression *car;
 249                         struct expression *cdr;
 250                 } dns_transaction;
 251                 struct {
 252                         unsigned rrclass;
 253                         unsigned rrtype;
 254                         struct expression *rrname;
 255                         struct expression *rrdata;
 256                         struct expression *ttl;
 257                 } ns_add;
 258                 struct {
 259                         unsigned rrclass;
 260                         unsigned rrtype;
 261                         struct expression *rrname;
 262                         struct expression *rrdata;
 263                 } ns_delete, ns_exists, ns_not_exists;
 264                 char *variable;
 265                 struct {
 266                         struct expression *val;
 267                         struct expression *next;
 268                 } arg;
 269                 struct {
 270                         char *name;
 271                         struct expression *arglist;
 272                 } funcall;
 273                 struct fundef *func;
 274         } data;
 275         int flags;
 276 #       define EXPR_EPHEMERAL   1
 277 };
 278
 279 /* DNS host entry structure... */
 280 struct dns_host_entry {
 281         int refcnt;
 282         TIME timeout;
 283         struct data_string data;
 284         char hostname [1];
 285 };
 286
 287 struct option_cache; /* forward */
 288 struct packet; /* forward */
 289 struct option_state; /* forward */
 290 struct decoded_option_state; /* forward */
 291 struct lease; /* forward */
 292 struct client_state; /* forward */
 293
 294 struct universe {
 295         const char *name;
 296         struct option_cache *(*lookup_func) (struct universe *,
 297                                              struct option_state *,
 298                                              unsigned);
 299         void (*save_func) (struct universe *, struct option_state *,
 300                            struct option_cache *);
 301         void (*foreach) (struct packet *,
 302                          struct lease *, struct client_state *,
 303                          struct option_state *, struct option_state *,
 304                          struct binding_scope **, struct universe *, void *,
 305                          void (*) (struct option_cache *, struct packet *,
 306                                    struct lease *, struct client_state *,
 307                                    struct option_state *,
 308                                    struct option_state *,
 309                                    struct binding_scope **,
 310                                    struct universe *, void *));
 311         void (*delete_func) (struct universe *universe,
 312                              struct option_state *, int);
 313         int (*option_state_dereference) (struct universe *,
 314                                          struct option_state *,
 315                                          const char *, int);
 316         int (*decode) (struct option_state *,
 317                        const unsigned char *, unsigned, struct universe *);
 318         int (*encapsulate) (struct data_string *, struct packet *,
 319                             struct lease *, struct client_state *,
 320                             struct option_state *, struct option_state *,
 321                             struct binding_scope **,
 322                             struct universe *);
 323         void (*store_tag) PROTO ((unsigned char *, u_int32_t));
 324         void (*store_length) PROTO ((unsigned char *, u_int32_t));
 325         int tag_size, length_size;
 326         option_hash_t *hash;
 327         struct option *options [256];
 328         struct option *enc_opt;
 329         int index;
 330 };
 331
 332 struct option {
 333         const char *name;
 334         const char *format;
 335         struct universe *universe;
 336         unsigned code;
 337 };