includes/tree.h

   1 /* tree.h
   2
   3    Definitions for address trees... */
   4
   5 /*
   6  * Copyright (c) 2004-2017 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 1996-2003 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  *   PO Box 360
  23  *   Newmarket, NH 03857 USA
  24  *   <info@isc.org>
  25  *   https://www.isc.org/
  26  *
  27  */
  28
  29 /* A pair of pointers, suitable for making a linked list. */
  30 typedef struct _pair {
  31         caddr_t car;
  32         struct _pair *cdr;
  33 } *pair;
  34
  35 struct option_chain_head {
  36         int refcnt;
  37         pair first;
  38 };
  39
  40 struct enumeration_value {
  41         const char *name;
  42         u_int8_t value;
  43 };
  44
  45 struct enumeration {
  46         struct enumeration *next;
  47         const char *name;
  48         unsigned width;
  49         struct enumeration_value *values;
  50 };
  51
  52 /* Tree node types... */
  53 #define TREE_CONCAT             1
  54 #define TREE_HOST_LOOKUP        2
  55 #define TREE_CONST              3
  56 #define TREE_LIMIT              4
  57 #define TREE_DATA_EXPR          5
  58
  59 /* A data buffer with a reference count. */
  60 struct buffer {
  61         int refcnt;
  62         unsigned char data [1];
  63 };
  64
  65 /* XXX The mechanism by which data strings are returned is currently
  66    XXX broken: rather than returning an ephemeral pointer, we create
  67    XXX a reference to the data in the caller's space, which the caller
  68    XXX then has to dereference - instead, the reference should be
  69    XXX ephemeral by default and be made a persistent reference explicitly. */
  70 /* XXX on the other hand, it seems to work pretty nicely, so maybe the
  71    XXX above comment is meshuggenah. */
  72 /* XXX I think the above comment tries to say this:
  73    XXX    http://tinyurl.com/2tjqre */
  74
  75 /* A string of data bytes, possibly accompanied by a larger buffer. */
  76 struct data_string {
  77         struct buffer *buffer;
  78         const unsigned char *data;
  79         unsigned len;   /* Does not include NUL terminator, if any. */
  80         int terminated;
  81 };
  82
  83 enum expression_context {
  84         context_any, /* indefinite */
  85         context_boolean,
  86         context_data,
  87         context_numeric,
  88         context_dns,
  89         context_data_or_numeric, /* indefinite */
  90         context_function
  91 };
  92
  93 struct fundef {
  94         int refcnt;
  95         struct string_list *args;
  96         struct executable_statement *statements;
  97 };
  98
  99 struct binding_value {
 100         int refcnt;
 101         enum {
 102                 binding_boolean,
 103                 binding_data,
 104                 binding_numeric,
 105                 binding_dns,
 106                 binding_function
 107         } type;
 108         union value {
 109                 struct data_string data;
 110                 unsigned long intval;
 111                 int boolean;
 112                 struct fundef *fundef;
 113                 struct binding_value *bv;
 114         } value;
 115 };
 116
 117 struct binding {
 118         struct binding *next;
 119         char *name;
 120         struct binding_value *value;
 121 };
 122
 123 struct binding_scope {
 124         int refcnt;
 125         struct binding_scope *outer;
 126         struct binding *bindings;
 127 };
 128
 129 /* Expression tree structure. */
 130
 131 enum expr_op {
 132         expr_none,
 133         expr_match,
 134         expr_check,
 135         expr_equal,
 136         expr_substring,
 137         expr_suffix,
 138         expr_concat,
 139         expr_host_lookup,
 140         expr_and,
 141         expr_or,
 142         expr_not,
 143         expr_option,
 144         expr_hardware,
 145         expr_packet,
 146         expr_const_data,
 147         expr_extract_int8,
 148         expr_extract_int16,
 149         expr_extract_int32,
 150         expr_encode_int8,
 151         expr_encode_int16,
 152         expr_encode_int32,
 153         expr_const_int,
 154         expr_exists,
 155         expr_encapsulate,
 156         expr_known,
 157         expr_reverse,
 158         expr_leased_address,
 159         expr_binary_to_ascii,
 160         expr_config_option,
 161         expr_host_decl_name,
 162         expr_pick_first_value,
 163         expr_lease_time,
 164         expr_dns_transaction,
 165         expr_static,
 166         expr_ns_add,
 167         expr_ns_delete,
 168         expr_ns_exists,
 169         expr_ns_not_exists,
 170         expr_not_equal,
 171         expr_null,
 172         expr_variable_exists,
 173         expr_variable_reference,
 174         expr_filename,
 175         expr_sname,
 176         expr_arg,
 177         expr_funcall,
 178         expr_function,
 179         expr_add,
 180         expr_subtract,
 181         expr_multiply,
 182         expr_divide,
 183         expr_remainder,
 184         expr_binary_and,
 185         expr_binary_or,
 186         expr_binary_xor,
 187         expr_client_state,
 188         expr_ucase,
 189         expr_lcase,
 190         expr_regex_match,
 191         expr_iregex_match,
 192         expr_gethostname,
 193         expr_v6relay,
 194         expr_concat_dclist
 195 };
 196
 197 struct expression {
 198         int refcnt;
 199         enum expr_op op;
 200         union expr_union {
 201                 struct {
 202                         struct expression *expr;
 203                         struct expression *offset;
 204                         struct expression *len;
 205                 } substring;
 206                 struct expression *equal [2];
 207                 struct expression *and [2];
 208                 struct expression *or [2];
 209                 struct expression *not;
 210                 struct expression *add;
 211                 struct expression *subtract;
 212                 struct expression *multiply;
 213                 struct expression *divide;
 214                 struct expression *remainder;
 215                 struct collection *check;
 216                 struct {
 217                         struct expression *expr;
 218                         struct expression *len;
 219                 } suffix;
 220                 struct expression *lcase;
 221                 struct expression *ucase;
 222                 struct option *option;
 223                 struct option *config_option;
 224                 struct {
 225                         struct expression *offset;
 226                         struct expression *len;
 227                 } packet;
 228                 struct data_string const_data;
 229                 struct expression *extract_int;
 230                 struct expression *encode_int;
 231                 unsigned long const_int;
 232                 struct expression *concat [2];
 233                 struct dns_host_entry *host_lookup;
 234                 struct option *exists;
 235                 struct data_string encapsulate;
 236                 struct {
 237                         struct expression *base;
 238                         struct expression *width;
 239                         struct expression *separator;
 240                         struct expression *buffer;
 241                 } b2a;
 242                 struct {
 243                         struct expression *width;
 244                         struct expression *buffer;
 245                 } reverse;
 246                 struct {
 247                         struct expression *car;
 248                         struct expression *cdr;
 249                 } pick_first_value;
 250                 struct {
 251                         struct expression *car;
 252                         struct expression *cdr;
 253                 } dns_transaction;
 254                 struct {
 255                         unsigned rrclass;
 256                         unsigned rrtype;
 257                         struct expression *rrname;
 258                         struct expression *rrdata;
 259                         struct expression *ttl;
 260                 } ns_add;
 261                 struct {
 262                         unsigned rrclass;
 263                         unsigned rrtype;
 264                         struct expression *rrname;
 265                         struct expression *rrdata;
 266                 } ns_delete, ns_exists, ns_not_exists;
 267                 char *variable;
 268                 struct {
 269                         struct expression *val;
 270                         struct expression *next;
 271                 } arg;
 272                 struct {
 273                         char *name;
 274                         struct expression *arglist;
 275                 } funcall;
 276                 struct fundef *func;
 277                 struct {
 278                         struct expression *relay;
 279                         struct expression *roption;
 280                 } v6relay;
 281         } data;
 282         int flags;
 283 #       define EXPR_EPHEMERAL   1
 284 };
 285
 286 /* DNS host entry structure... */
 287 struct dns_host_entry {
 288         int refcnt;
 289         TIME timeout;
 290         struct data_string data;
 291         char hostname [1];
 292 };
 293
 294 struct option_cache; /* forward */
 295 struct packet; /* forward */
 296 struct option_state; /* forward */
 297 struct decoded_option_state; /* forward */
 298 struct lease; /* forward */
 299 struct client_state; /* forward */
 300
 301 struct universe {
 302         const char *name;
 303         struct option_cache *(*lookup_func) (struct universe *,
 304                                              struct option_state *,
 305                                              unsigned);
 306         void (*save_func) (struct universe *, struct option_state *,
 307                            struct option_cache *, isc_boolean_t);
 308         void (*foreach) (struct packet *,
 309                          struct lease *, struct client_state *,
 310                          struct option_state *, struct option_state *,
 311                          struct binding_scope **, struct universe *, void *,
 312                          void (*) (struct option_cache *, struct packet *,
 313                                    struct lease *, struct client_state *,
 314                                    struct option_state *,
 315                                    struct option_state *,
 316                                    struct binding_scope **,
 317                                    struct universe *, void *));
 318         void (*delete_func) (struct universe *universe,
 319                              struct option_state *, int);
 320         int (*option_state_dereference) (struct universe *,
 321                                          struct option_state *,
 322                                          const char *, int);
 323         int (*decode) (struct option_state *,
 324                        const unsigned char *, unsigned, struct universe *);
 325         int (*encapsulate) (struct data_string *, struct packet *,
 326                             struct lease *, struct client_state *,
 327                             struct option_state *, struct option_state *,
 328                             struct binding_scope **,
 329                             struct universe *);
 330         u_int32_t (*get_tag) (const unsigned char *);
 331         void (*store_tag) (unsigned char *, u_int32_t);
 332         u_int32_t (*get_length) (const unsigned char *);
 333         void (*store_length) (unsigned char *, u_int32_t);
 334         int tag_size, length_size;
 335         unsigned site_code_min, end;
 336         option_name_hash_t *name_hash;
 337         option_code_hash_t *code_hash;
 338         struct option *enc_opt;
 339         int index;
 340
 341         /* Flags should probably become condensed. */
 342         int concat_duplicates;
 343 };
 344
 345 struct option {
 346         const char *name;
 347         const char *format;
 348         struct universe *universe;
 349         unsigned code;
 350         int refcnt;
 351 };