includes/tree.h

   1 /* tree.h
   2
   3    Definitions for address trees... */
   4
   5 /*
   6  * Copyright (c) 2004,2007-2008 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  *   https://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  * ``https://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         unsigned width;
  55         struct enumeration_value *values;
  56 };
  57
  58 /* Tree node types... */
  59 #define TREE_CONCAT             1
  60 #define TREE_HOST_LOOKUP        2
  61 #define TREE_CONST              3
  62 #define TREE_LIMIT              4
  63 #define TREE_DATA_EXPR          5
  64
  65 /* A data buffer with a reference count. */
  66 struct buffer {
  67         int refcnt;
  68         unsigned char data [1];
  69 };
  70
  71 /* XXX The mechanism by which data strings are returned is currently
  72    XXX broken: rather than returning an ephemeral pointer, we create
  73    XXX a reference to the data in the caller's space, which the caller
  74    XXX then has to dereference - instead, the reference should be
  75    XXX ephemeral by default and be made a persistent reference explicitly. */
  76 /* XXX on the other hand, it seems to work pretty nicely, so maybe the
  77    XXX above comment is meshuggenah. */
  78 /* XXX I think the above comment tries to say this:
  79    XXX    http://tinyurl.com/2tjqre */
  80
  81 /* A string of data bytes, possibly accompanied by a larger buffer. */
  82 struct data_string {
  83         struct buffer *buffer;
  84         const unsigned char *data;
  85         unsigned len;   /* Does not include NUL terminator, if any. */
  86         int terminated;
  87 };
  88
  89 enum expression_context {
  90         context_any, /* indefinite */
  91         context_boolean,
  92         context_data,
  93         context_numeric,
  94         context_dns,
  95         context_data_or_numeric, /* indefinite */
  96         context_function
  97 };
  98
  99 struct fundef {
 100         int refcnt;
 101         struct string_list *args;
 102         struct executable_statement *statements;
 103 };
 104
 105 struct binding_value {
 106         int refcnt;
 107         enum {
 108                 binding_boolean,
 109                 binding_data,
 110                 binding_numeric,
 111                 binding_dns,
 112                 binding_function
 113         } type;
 114         union value {
 115                 struct data_string data;
 116                 unsigned long intval;
 117                 int boolean;
 118 #if defined (NSUPDATE_OLD)
 119                 ns_updrec *dns;
 120 #endif
 121                 struct fundef *fundef;
 122                 struct binding_value *bv;
 123         } value;
 124 };
 125
 126 struct binding {
 127         struct binding *next;
 128         char *name;
 129         struct binding_value *value;
 130 };
 131
 132 struct binding_scope {
 133         int refcnt;
 134         struct binding_scope *outer;
 135         struct binding *bindings;
 136 };
 137
 138 /* Expression tree structure. */
 139
 140 enum expr_op {
 141         expr_none,
 142         expr_match,
 143         expr_check,
 144         expr_equal,
 145         expr_substring,
 146         expr_suffix,
 147         expr_concat,
 148         expr_host_lookup,
 149         expr_and,
 150         expr_or,
 151         expr_not,
 152         expr_option,
 153         expr_hardware,
 154         expr_packet,
 155         expr_const_data,
 156         expr_extract_int8,
 157         expr_extract_int16,
 158         expr_extract_int32,
 159         expr_encode_int8,
 160         expr_encode_int16,
 161         expr_encode_int32,
 162         expr_const_int,
 163         expr_exists,
 164         expr_encapsulate,
 165         expr_known,
 166         expr_reverse,
 167         expr_leased_address,
 168         expr_binary_to_ascii,
 169         expr_config_option,
 170         expr_host_decl_name,
 171         expr_pick_first_value,
 172         expr_lease_time,
 173         expr_dns_transaction,
 174         expr_static,
 175         expr_ns_add,
 176         expr_ns_delete,
 177         expr_ns_exists,
 178         expr_ns_not_exists,
 179         expr_not_equal,
 180         expr_null,
 181         expr_variable_exists,
 182         expr_variable_reference,
 183         expr_filename,
 184         expr_sname,
 185         expr_arg,
 186         expr_funcall,
 187         expr_function,
 188         expr_add,
 189         expr_subtract,
 190         expr_multiply,
 191         expr_divide,
 192         expr_remainder,
 193         expr_binary_and,
 194         expr_binary_or,
 195         expr_binary_xor,
 196         expr_client_state,
 197         expr_ucase,
 198         expr_lcase,
 199         expr_regex_match,
 200         expr_iregex_match,
 201         expr_gethostname
 202 };
 203
 204 struct expression {
 205         int refcnt;
 206         enum expr_op op;
 207         union expr_union {
 208                 struct {
 209                         struct expression *expr;
 210                         struct expression *offset;
 211                         struct expression *len;
 212                 } substring;
 213                 struct expression *equal [2];
 214                 struct expression *and [2];
 215                 struct expression *or [2];
 216                 struct expression *not;
 217                 struct expression *add;
 218                 struct expression *subtract;
 219                 struct expression *multiply;
 220                 struct expression *divide;
 221                 struct expression *remainder;
 222                 struct collection *check;
 223                 struct {
 224                         struct expression *expr;
 225                         struct expression *len;
 226                 } suffix;
 227                 struct expression *lcase;
 228                 struct expression *ucase;
 229                 struct option *option;
 230                 struct option *config_option;
 231                 struct {
 232                         struct expression *offset;
 233                         struct expression *len;
 234                 } packet;
 235                 struct data_string const_data;
 236                 struct expression *extract_int;
 237                 struct expression *encode_int;
 238                 unsigned long const_int;
 239                 struct expression *concat [2];
 240                 struct dns_host_entry *host_lookup;
 241                 struct option *exists;
 242                 struct data_string encapsulate;
 243                 struct {
 244                         struct expression *base;
 245                         struct expression *width;
 246                         struct expression *separator;
 247                         struct expression *buffer;
 248                 } b2a;
 249                 struct {
 250                         struct expression *width;
 251                         struct expression *buffer;
 252                 } reverse;
 253                 struct {
 254                         struct expression *car;
 255                         struct expression *cdr;
 256                 } pick_first_value;
 257                 struct {
 258                         struct expression *car;
 259                         struct expression *cdr;
 260                 } dns_transaction;
 261                 struct {
 262                         unsigned rrclass;
 263                         unsigned rrtype;
 264                         struct expression *rrname;
 265                         struct expression *rrdata;
 266                         struct expression *ttl;
 267                 } ns_add;
 268                 struct {
 269                         unsigned rrclass;
 270                         unsigned rrtype;
 271                         struct expression *rrname;
 272                         struct expression *rrdata;
 273                 } ns_delete, ns_exists, ns_not_exists;
 274                 char *variable;
 275                 struct {
 276                         struct expression *val;
 277                         struct expression *next;
 278                 } arg;
 279                 struct {
 280                         char *name;
 281                         struct expression *arglist;
 282                 } funcall;
 283                 struct fundef *func;
 284         } data;
 285         int flags;
 286 #       define EXPR_EPHEMERAL   1
 287 };
 288
 289 /* DNS host entry structure... */
 290 struct dns_host_entry {
 291         int refcnt;
 292         TIME timeout;
 293         struct data_string data;
 294         char hostname [1];
 295 };
 296
 297 struct option_cache; /* forward */
 298 struct packet; /* forward */
 299 struct option_state; /* forward */
 300 struct decoded_option_state; /* forward */
 301 struct lease; /* forward */
 302 struct client_state; /* forward */
 303
 304 struct universe {
 305         const char *name;
 306         struct option_cache *(*lookup_func) (struct universe *,
 307                                              struct option_state *,
 308                                              unsigned);
 309         void (*save_func) (struct universe *, struct option_state *,
 310                            struct option_cache *, isc_boolean_t);
 311         void (*foreach) (struct packet *,
 312                          struct lease *, struct client_state *,
 313                          struct option_state *, struct option_state *,
 314                          struct binding_scope **, struct universe *, void *,
 315                          void (*) (struct option_cache *, struct packet *,
 316                                    struct lease *, struct client_state *,
 317                                    struct option_state *,
 318                                    struct option_state *,
 319                                    struct binding_scope **,
 320                                    struct universe *, void *));
 321         void (*delete_func) (struct universe *universe,
 322                              struct option_state *, int);
 323         int (*option_state_dereference) (struct universe *,
 324                                          struct option_state *,
 325                                          const char *, int);
 326         int (*decode) (struct option_state *,
 327                        const unsigned char *, unsigned, struct universe *);
 328         int (*encapsulate) (struct data_string *, struct packet *,
 329                             struct lease *, struct client_state *,
 330                             struct option_state *, struct option_state *,
 331                             struct binding_scope **,
 332                             struct universe *);
 333         u_int32_t (*get_tag) (const unsigned char *);
 334         void (*store_tag) PROTO ((unsigned char *, u_int32_t));
 335         u_int32_t (*get_length) (const unsigned char *);
 336         void (*store_length) PROTO ((unsigned char *, u_int32_t));
 337         int tag_size, length_size;
 338         unsigned site_code_min, end;
 339         option_name_hash_t *name_hash;
 340         option_code_hash_t *code_hash;
 341         struct option *enc_opt;
 342         int index;
 343
 344         /* Flags should probably become condensed. */
 345         int concat_duplicates;
 346 };
 347
 348 struct option {
 349         const char *name;
 350         const char *format;
 351         struct universe *universe;
 352         unsigned code;
 353         int refcnt;
 354 };