dist/dhcp/server/class.c

   1 /* class.c
   2
   3    Handling for client classes. */
   4
   5 /*
   6  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 1998-2003 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 #ifndef lint
  36 static char copyright[] =
  37 "$Id: class.c,v 1.4 2005/08/11 17:13:30 drochner Exp $ Copyright (c) 2004 Internet Systems Consortium.  All rights reserved.\n";
  38
  39 #endif /* not lint */
  40
  41 #include "dhcpd.h"
  42
  43 struct collection default_collection = {
  44         (struct collection *)0,
  45         "default",
  46         (struct class *)0,
  47 };
  48
  49 struct collection *collections = &default_collection;
  50 struct executable_statement *default_classification_rules;
  51
  52 int have_billing_classes;
  53
  54 /* Build the default classification rule tree. */
  55
  56 void classification_setup ()
  57 {
  58         /* eval ... */
  59         default_classification_rules = (struct executable_statement *)0;
  60         if (!executable_statement_allocate (&default_classification_rules,
  61                                             MDL))
  62                 log_fatal ("Can't allocate check of default collection");
  63         default_classification_rules -> op = eval_statement;
  64
  65         /* check-collection "default" */
  66         if (!expression_allocate (&default_classification_rules -> data.eval,
  67                                   MDL))
  68                 log_fatal ("Can't allocate default check expression");
  69         default_classification_rules -> data.eval -> op = expr_check;
  70         default_classification_rules -> data.eval -> data.check =
  71                 &default_collection;
  72 }
  73
  74 void classify_client (packet)
  75         struct packet *packet;
  76 {
  77         execute_statements ((struct binding_value **)0, packet,
  78                             (struct lease *)0, (struct client_state *)0,
  79                             packet -> options, (struct option_state *)0,
  80                             &global_scope, default_classification_rules);
  81 }
  82
  83 int check_collection (packet, lease, collection)
  84         struct packet *packet;
  85         struct lease *lease;
  86         struct collection *collection;
  87 {
  88         struct class *class, *nc;
  89         struct data_string data;
  90         int matched = 0;
  91         int status;
  92         int ignorep;
  93
  94         for (class = collection -> classes; class; class = class -> nic) {
  95 #if defined (DEBUG_CLASS_MATCHING)
  96                 log_info ("checking against class %s...", class -> name);
  97 #endif
  98                 memset (&data, 0, sizeof data);
  99
 100                 /* If there is a "match if" expression, check it.   If
 101                    we get a match, and there's no subclass expression,
 102                    it's a match.   If we get a match and there is a subclass
 103                    expression, then we check the submatch.   If it's not a
 104                    match, that's final - we don't check the submatch. */
 105
 106                 if (class -> expr) {
 107                         status = (evaluate_boolean_expression_result
 108                                   (&ignorep, packet, lease,
 109                                    (struct client_state *)0,
 110                                    packet -> options, (struct option_state *)0,
 111                                    lease ? &lease -> scope : &global_scope,
 112                                    class -> expr));
 113                         if (status) {
 114                                 if (!class -> submatch) {
 115                                         matched = 1;
 116 #if defined (DEBUG_CLASS_MATCHING)
 117                                         log_info ("matches class.");
 118 #endif
 119                                         classify (packet, class);
 120                                         continue;
 121                                 }
 122                         } else
 123                                 continue;
 124                 }
 125
 126                 /* Check to see if the client matches an existing subclass.
 127                    If it doesn't, and this is a spawning class, spawn a new
 128                    subclass and put the client in it. */
 129                 if (class -> submatch) {
 130                         status = (evaluate_data_expression
 131                                   (&data, packet, lease,
 132                                    (struct client_state *)0,
 133                                    packet -> options, (struct option_state *)0,
 134                                    lease ? &lease -> scope : &global_scope,
 135                                    class -> submatch, MDL));
 136                         if (status && data.len) {
 137                                 nc = (struct class *)0;
 138                                 if (class_hash_lookup (&nc, class -> hash,
 139                                                        (const char *)data.data,
 140                                                        data.len, MDL)) {
 141 #if defined (DEBUG_CLASS_MATCHING)
 142                                         log_info ("matches subclass %s.",
 143                                               print_hex_1 (data.len,
 144                                                            data.data, 60));
 145 #endif
 146                                         data_string_forget (&data, MDL);
 147                                         classify (packet, nc);
 148                                         matched = 1;
 149                                         class_dereference (&nc, MDL);
 150                                         continue;
 151                                 }
 152                                 if (!class -> spawning) {
 153                                         data_string_forget (&data, MDL);
 154                                         continue;
 155                                 }
 156                                 /* XXX Write out the spawned class? */
 157 #if defined (DEBUG_CLASS_MATCHING)
 158                                 log_info ("spawning subclass %s.",
 159                                       print_hex_1 (data.len, data.data, 60));
 160 #endif
 161                                 status = class_allocate (&nc, MDL);
 162                                 group_reference (&nc -> group,
 163                                                  class -> group, MDL);
 164                                 class_reference (&nc -> superclass,
 165                                                  class, MDL);
 166                                 nc -> lease_limit = class -> lease_limit;
 167                                 nc -> dirty = 1;
 168                                 if (nc -> lease_limit) {
 169                                         nc -> billed_leases =
 170                                                 (dmalloc
 171                                                  (nc -> lease_limit *
 172                                                   sizeof (struct lease *),
 173                                                   MDL));
 174                                         if (!nc -> billed_leases) {
 175                                                 log_error ("no memory for%s",
 176                                                            " billing");
 177                                                 data_string_forget
 178                                                         (&nc -> hash_string,
 179                                                          MDL);
 180                                                 class_dereference (&nc, MDL);
 181                                                 data_string_forget (&data,
 182                                                                     MDL);
 183                                                 continue;
 184                                         }
 185                                         memset (nc -> billed_leases, 0,
 186                                                 (nc -> lease_limit *
 187                                                  sizeof nc -> billed_leases));
 188                                 }
 189                                 data_string_copy (&nc -> hash_string, &data,
 190                                                   MDL);
 191                                 data_string_forget (&data, MDL);
 192                                 if (!class -> hash)
 193                                     class_new_hash (&class -> hash, 0, MDL);
 194                                 class_hash_add (class -> hash,
 195                                                 (const char *)
 196                                                 nc -> hash_string.data,
 197                                                 nc -> hash_string.len,
 198                                                 nc, MDL);
 199                                 classify (packet, nc);
 200                                 class_dereference (&nc, MDL);
 201                         }
 202                 }
 203         }
 204         return matched;
 205 }
 206
 207 void classify (packet, class)
 208         struct packet *packet;
 209         struct class *class;
 210 {
 211         if (packet -> class_count < PACKET_MAX_CLASSES)
 212                 class_reference (&packet -> classes [packet -> class_count++],
 213                                  class, MDL);
 214         else
 215                 log_error ("too many classes match %s",
 216                       print_hw_addr (packet -> raw -> htype,
 217                                      packet -> raw -> hlen,
 218                                      packet -> raw -> chaddr));
 219 }
 220
 221 isc_result_t find_class (struct class **class, const char *name,
 222                          const char *file, int line)
 223 {
 224         struct collection *lp;
 225         struct class *cp;
 226
 227         for (lp = collections; lp; lp = lp -> next) {
 228                 for (cp = lp -> classes; cp; cp = cp -> nic)
 229                         if (cp -> name && !strcmp (name, cp -> name)) {
 230                                 return class_reference (class, cp, file, line);
 231                         }
 232         }
 233         return ISC_R_NOTFOUND;
 234 }
 235
 236 int unbill_class (lease, class)
 237         struct lease *lease;
 238         struct class *class;
 239 {
 240         int i;
 241
 242         for (i = 0; i < class -> lease_limit; i++)
 243                 if (class -> billed_leases [i] == lease)
 244                         break;
 245         if (i == class -> lease_limit) {
 246                 log_error ("lease %s unbilled with no billing arrangement.",
 247                       piaddr (lease -> ip_addr));
 248                 return 0;
 249         }
 250         class_dereference (&lease -> billing_class, MDL);
 251         lease_dereference (&class -> billed_leases [i], MDL);
 252         class -> leases_consumed--;
 253         return 1;
 254 }
 255
 256 int bill_class (lease, class)
 257         struct lease *lease;
 258         struct class *class;
 259 {
 260         int i;
 261
 262         if (lease -> billing_class) {
 263                 log_error ("lease billed with existing billing arrangement.");
 264                 unbill_class (lease, lease -> billing_class);
 265         }
 266
 267         if (class -> leases_consumed == class -> lease_limit)
 268                 return 0;
 269
 270         for (i = 0; i < class -> lease_limit; i++)
 271                 if (!class -> billed_leases [i])
 272                         break;
 273
 274         if (i == class -> lease_limit) {
 275                 log_error ("class billing consumption disagrees with leases.");
 276                 return 0;
 277         }
 278
 279         lease_reference (&class -> billed_leases [i], lease, MDL);
 280         class_reference (&lease -> billing_class, class, MDL);
 281         class -> leases_consumed++;
 282         return 1;
 283 }