Source/charon/sa/states/responder_init.c

   1 /**
   2  * @file responder_init.c
   3  *
   4  * @brief Implementation of responder_init_t.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005 Jan Hutter, Martin Willi
  10  * Hochschule fuer Technik Rapperswil
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 2 of the License, or (at your
  15  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  */
  22
  23 #include "responder_init.h"
  24
  25 #include <daemon.h>
  26 #include <sa/states/state.h>
  27 #include <sa/states/ike_sa_init_responded.h>
  28 #include <utils/allocator.h>
  29 #include <encoding/payloads/sa_payload.h>
  30 #include <encoding/payloads/ke_payload.h>
  31 #include <encoding/payloads/nonce_payload.h>
  32 #include <transforms/diffie_hellman.h>
  33
  34
  35 typedef struct private_responder_init_t private_responder_init_t;
  36
  37 /**
  38  * Private data of a responder_init_t object.
  39  *
  40  */
  41 struct private_responder_init_t {
  42         /**
  43          * Methods of the state_t interface.
  44          */
  45         responder_init_t public;
  46
  47         /**
  48          * Assigned IKE_SA.
  49          */
  50         protected_ike_sa_t *ike_sa;
  51
  52         /**
  53          * Diffie Hellman object used to compute shared secret.
  54          *
  55          * After processing of incoming IKE_SA_INIT-Request the shared key is
  56          * passed to the next state of type ike_sa_init_responded_t.
  57          */
  58         diffie_hellman_t *diffie_hellman;
  59
  60         /**
  61          * Diffie Hellman group number.
  62          */
  63         u_int16_t dh_group_number;
  64
  65         /**
  66          * Priority used to get matching dh_group number.
  67          */
  68         u_int16_t dh_group_priority;
  69
  70         /**
  71          * Sent nonce value.
  72          *
  73          * This value is passed to the next state of type ike_sa_init_responded_t.
  74          */
  75         chunk_t sent_nonce;
  76
  77         /**
  78          * Received nonce value
  79          *
  80          * This value is passed to the next state of type ike_sa_init_responded_t.
  81          */
  82         chunk_t received_nonce;
  83
  84         /**
  85          * Logger used to log data
  86          *
  87          * Is logger of ike_sa!
  88          */
  89         logger_t *logger;
  90
  91         /**
  92          * Selected proposal from suggested ones.
  93          */
  94         ike_proposal_t selected_proposal;
  95
  96         /**
  97          * Builds the SA payload for this state.
  98          *
  99          * @param this          calling object
 100          * @param payload       The generated SA payload object of type ke_payload_t is
 101          *                                      stored at this location.
 102          */
 103         void (*build_sa_payload) (private_responder_init_t *this, payload_t **payload);
 104
 105         /**
 106          * Builds the KE payload for this state.
 107          *
 108          * @param this          calling object
 109          * @param payload       The generated KE payload object of type ke_payload_t is
 110          *                                      stored at this location.
 111          */
 112         void (*build_ke_payload) (private_responder_init_t *this, payload_t **payload);
 113
 114         /**
 115          * Builds the NONCE payload for this state.
 116          *
 117          * @param this          calling object
 118          * @param payload       The generated NONCE payload object of type ke_payload_t is
 119          *                                      stored at this location.
 120          */
 121         void (*build_nonce_payload) (private_responder_init_t *this, payload_t **payload);
 122
 123         /**
 124          * Destroy function called internally of this class after state change succeeded.
 125          *
 126          * This destroy function does not destroy objects which were passed to the new state.
 127          *
 128          * @param this          calling object
 129          */
 130         void (*destroy_after_state_change) (private_responder_init_t *this);
 131 };
 132
 133 /**
 134  * Implements state_t.get_state
 135  */
 136 static status_t process_message(private_responder_init_t *this, message_t *message)
 137 {
 138         iterator_t *payloads;
 139         host_t *source, *destination;
 140         status_t status;
 141         message_t *response;
 142         payload_t *payload;
 143         packet_t *packet;
 144         chunk_t shared_secret;
 145         exchange_type_t exchange_type;
 146         ike_sa_init_responded_t *next_state;
 147         host_t *my_host;
 148         host_t *other_host;
 149         randomizer_t *randomizer;
 150         init_config_t *init_config;
 151         diffie_hellman_group_t dh_group = MODP_UNDEFINED;
 152
 153         exchange_type = message->get_exchange_type(message);
 154         if (exchange_type != IKE_SA_INIT)
 155         {
 156                 this->logger->log(this->logger, ERROR | MORE, "Message of type %s not supported in state responder_init",mapping_find(exchange_type_m,exchange_type));
 157                 return FAILED;
 158         }
 159         if (!message->get_request(message))
 160         {
 161                 this->logger->log(this->logger, ERROR | MORE, "Only requests of type IKE_SA_INIT supported in state responder_init");
 162                 return FAILED;
 163         }
 164         /* this is the first message we process, so copy host infos */
 165         source = message->get_source(message);
 166         destination = message->get_destination(message);
 167
 168         status = charon->configuration_manager->get_init_config_for_host(charon->configuration_manager,destination,source,&init_config);
 169
 170         if (status != SUCCESS)
 171         {
 172                 /* no configuration matches given host */
 173                 this->logger->log(this->logger, ERROR | MORE, "No INIT configuration found for given remote and local hosts");
 174                 return FAILED;
 175         }
 176
 177         this->ike_sa->set_init_config(this->ike_sa,init_config);
 178
 179
 180         /* we need to clone them, since we destroy the message later */
 181         my_host = destination->clone(destination);
 182         other_host = source->clone(source);
 183
 184         this->ike_sa->set_my_host(this->ike_sa, my_host);
 185         this->ike_sa->set_other_host(this->ike_sa, other_host);
 186
 187         /* parse incoming message */
 188         status = message->parse_body(message, NULL, NULL);
 189         if (status != SUCCESS)
 190         {
 191                 this->logger->log(this->logger, ERROR | MORE, "Could not parse body of request message");
 192                 return status;
 193         }
 194         /* iterate over incoming payloads. We can be sure, the message contains only accepted payloads! */
 195         payloads = message->get_payload_iterator(message);
 196
 197         while (payloads->has_next(payloads))
 198         {
 199                 payload_t *payload;
 200
 201                 /* get current payload */
 202                 payloads->current(payloads, (void**)&payload);
 203
 204                 this->logger->log(this->logger, CONTROL|MORE, "Processing payload of type %s", mapping_find(payload_type_m, payload->get_type(payload)));
 205                 switch (payload->get_type(payload))
 206                 {
 207                         case SECURITY_ASSOCIATION:
 208                         {
 209                                 sa_payload_t *sa_payload = (sa_payload_t*)payload;
 210                                 ike_proposal_t *ike_proposals;
 211                                 size_t proposal_count;
 212
 213                                 /* get the list of suggested proposals */
 214                                 status = sa_payload->get_ike_proposals (sa_payload, &ike_proposals,&proposal_count);
 215                                 if (status != SUCCESS)
 216                                 {
 217                                         this->logger->log(this->logger, ERROR | MORE, "SA payload does not contain IKE proposals");
 218                                         payloads->destroy(payloads);
 219                                         return status;
 220                                 }
 221
 222                                 status = init_config->select_proposal(init_config, ike_proposals,proposal_count,&(this->selected_proposal));
 223                                 allocator_free(ike_proposals);
 224                                 if (status != SUCCESS)
 225                                 {
 226                                         this->logger->log(this->logger, ERROR | MORE, "No proposal of suggested proposals selected");
 227                                         payloads->destroy(payloads);
 228                                         return status;
 229                                 }
 230
 231                                 dh_group = this->selected_proposal.diffie_hellman_group;
 232
 233                                 status = this->ike_sa->create_transforms_from_proposal(this->ike_sa,&(this->selected_proposal));
 234                                 if (status != SUCCESS)
 235                                 {
 236                                         this->logger->log(this->logger, ERROR | MORE, "Transform objects could not be created from selected proposal");
 237                                         payloads->destroy(payloads);
 238                                         return status;
 239                                 }
 240
 241                                 this->logger->log(this->logger, CONTROL | MORE, "SA Payload processed");
 242                                 /* ok, we have what we need for sa_payload (proposals are stored in this->proposals)*/
 243                                 break;
 244                         }
 245                         case KEY_EXCHANGE:
 246                         {
 247                                 ke_payload_t *ke_payload = (ke_payload_t*)payload;
 248                                 diffie_hellman_group_t group;
 249                                 diffie_hellman_t *dh;
 250                                 bool allowed_group;
 251
 252                                 group = ke_payload->get_dh_group_number(ke_payload);
 253
 254                                 if (dh_group == MODP_UNDEFINED)
 255                                 {
 256                                         this->logger->log(this->logger, ERROR | MORE, "Could not get informations about DH group. SA payload before KE payload?");
 257                                         payloads->destroy(payloads);
 258                                         return status;
 259                                 }
 260                                 if (!allowed_group)
 261                                 {
 262                                         /** @todo Send info reply */
 263                                 }
 264
 265                                 /* create diffie hellman object to handle DH exchange */
 266                                 dh = diffie_hellman_create(group);
 267                                 if (dh == NULL)
 268                                 {
 269                                         this->logger->log(this->logger, ERROR, "Could not generate DH object");
 270                                         payloads->destroy(payloads);
 271                                         return NOT_SUPPORTED;
 272                                 }
 273                                 this->logger->log(this->logger, CONTROL | MORE, "Set other DH public value");
 274
 275                                 dh->set_other_public_value(dh, ke_payload->get_key_exchange_data(ke_payload));
 276
 277                                 this->diffie_hellman = dh;
 278
 279                                 this->logger->log(this->logger, CONTROL | MORE, "KE Payload processed");
 280                                 break;
 281                         }
 282                         case NONCE:
 283                         {
 284                                 nonce_payload_t *nonce_payload = (nonce_payload_t*)payload;
 285
 286                                 allocator_free(this->received_nonce.ptr);
 287                                 this->received_nonce = CHUNK_INITIALIZER;
 288
 289                                 this->logger->log(this->logger, CONTROL | MORE, "Get nonce value and store it");
 290                                 nonce_payload->get_nonce(nonce_payload, &(this->received_nonce));
 291
 292                                 this->logger->log(this->logger, CONTROL | MORE, "Nonce Payload processed");
 293                                 break;
 294                         }
 295                         default:
 296                         {
 297                                 this->logger->log(this->logger, ERROR | MORE, "Payload type not supported!");
 298                                 payloads->destroy(payloads);
 299                                 return NOT_SUPPORTED;
 300                         }
 301                 }
 302         }
 303         /* iterator can be destroyed */
 304         payloads->destroy(payloads);
 305
 306         this->logger->log(this->logger, CONTROL | MORE, "Request successfully handled. Going to create reply.");
 307
 308         this->logger->log(this->logger, CONTROL | MOST, "Going to create nonce.");
 309
 310         randomizer = this->ike_sa->get_randomizer(this->ike_sa);
 311
 312         randomizer->allocate_pseudo_random_bytes(randomizer, NONCE_SIZE, &(this->sent_nonce));
 313
 314         /* store shared secret  */
 315         this->logger->log(this->logger, CONTROL | MOST, "Retrieve shared secret and store it");
 316         status = this->diffie_hellman->get_shared_secret(this->diffie_hellman, &shared_secret);
 317         this->logger->log_chunk(this->logger, PRIVATE, "Shared secret", &shared_secret);
 318
 319         this->ike_sa->compute_secrets(this->ike_sa,shared_secret,this->received_nonce, this->sent_nonce);
 320
 321         /* set up the reply */
 322         this->ike_sa->build_message(this->ike_sa, IKE_SA_INIT, FALSE, &response);
 323
 324
 325         /* build SA payload */
 326         this->build_sa_payload(this, &payload);
 327         this->logger->log(this->logger, CONTROL|MOST, "add SA payload to message");
 328         response->add_payload(response, payload);
 329
 330         /* build KE payload */
 331         this->build_ke_payload(this,&payload);
 332         this->logger->log(this->logger, CONTROL|MOST, "add KE payload to message");
 333         response->add_payload(response, payload);
 334
 335         /* build Nonce payload */
 336         this->build_nonce_payload(this, &payload);
 337         this->logger->log(this->logger, CONTROL|MOST, "add nonce payload to message");
 338         response->add_payload(response, payload);
 339
 340         /* generate packet */
 341         this->logger->log(this->logger, CONTROL|MOST, "generate packet from message");
 342         status = response->generate(response, NULL, NULL, &packet);
 343         if (status != SUCCESS)
 344         {
 345                 this->logger->log(this->logger, ERROR, "could not generate packet from message");
 346                 return status;
 347         }
 348
 349         this->logger->log(this->logger, CONTROL|MOST, "Add packet to global send queue");
 350          charon->send_queue->add(charon->send_queue, packet);
 351
 352         /* state can now be changed */
 353         this->logger->log(this->logger, CONTROL|MOST, "Create next state object");
 354
 355         next_state = ike_sa_init_responded_create(this->ike_sa, shared_secret, this->received_nonce, this->sent_nonce);
 356
 357         /* last message can now be set */
 358         status = this->ike_sa->set_last_responded_message(this->ike_sa, response);
 359
 360         if (status != SUCCESS)
 361         {
 362                 this->logger->log(this->logger, ERROR, "Could not set last responded message");
 363                 response->destroy(response);
 364                 (next_state->state_interface).destroy(&(next_state->state_interface));
 365                 return status;
 366         }
 367
 368         /* state can now be changed */
 369         this->ike_sa->set_new_state(this->ike_sa, (state_t *) next_state);
 370         /* state has NOW changed :-) */
 371         this->logger->log(this->logger, CONTROL|MORE, "Changed state of IKE_SA from %s to %s",mapping_find(ike_sa_state_m,RESPONDER_INIT),mapping_find(ike_sa_state_m,IKE_SA_INIT_RESPONDED) );
 372
 373         this->logger->log(this->logger, CONTROL|MOST, "Destroy old sate object");
 374         this->destroy_after_state_change(this);
 375
 376         return SUCCESS;
 377 }
 378
 379 /**
 380  * implements private_initiator_init_t.build_sa_payload
 381  */
 382 static void build_sa_payload(private_responder_init_t *this, payload_t **payload)
 383 {
 384         sa_payload_t* sa_payload;
 385
 386         /* SA payload takes proposals from this->ike_sa_init_data.proposals and writes them to the created sa_payload */
 387
 388         this->logger->log(this->logger, CONTROL|MORE, "building sa payload");
 389
 390         sa_payload = sa_payload_create_from_ike_proposals(&(this->selected_proposal),1);
 391
 392         *payload = (payload_t *) sa_payload;
 393 }
 394
 395 /**
 396  * implements private_initiator_init_t.build_ke_payload
 397  */
 398 static void build_ke_payload(private_responder_init_t *this, payload_t **payload)
 399 {
 400         ke_payload_t *ke_payload;
 401         chunk_t key_data;
 402
 403         this->logger->log(this->logger, CONTROL|MORE, "building ke payload");
 404         this->diffie_hellman->get_my_public_value(this->diffie_hellman,&key_data);
 405
 406         ke_payload = ke_payload_create();
 407         ke_payload->set_key_exchange_data(ke_payload,key_data);
 408         ke_payload->set_dh_group_number(ke_payload, MODP_1024_BIT);
 409
 410         allocator_free_chunk(&key_data);
 411         *payload = (payload_t *) ke_payload;
 412 }
 413
 414 /**
 415  * implements private_initiator_init_t.build_nonce_payload
 416  */
 417 static void build_nonce_payload(private_responder_init_t *this, payload_t **payload)
 418 {
 419         nonce_payload_t *nonce_payload;
 420         status_t status;
 421
 422         this->logger->log(this->logger, CONTROL|MORE, "building nonce payload");
 423
 424         nonce_payload = nonce_payload_create();
 425
 426         status = nonce_payload->set_nonce(nonce_payload, this->sent_nonce);
 427
 428         *payload = (payload_t *) nonce_payload;
 429 }
 430
 431
 432 /**
 433  * Implements state_t.get_state
 434  */
 435 static ike_sa_state_t get_state(private_responder_init_t *this)
 436 {
 437         return RESPONDER_INIT;
 438 }
 439
 440 /**
 441  * Implements state_t.get_state
 442  */
 443 static void destroy(private_responder_init_t *this)
 444 {
 445         this->logger->log(this->logger, CONTROL | MORE, "Going to destroy responder init state object");
 446
 447         /* destroy stored proposal */
 448         this->logger->log(this->logger, CONTROL | MOST, "Destroy stored proposals");
 449
 450         allocator_free(this->sent_nonce.ptr);
 451         allocator_free(this->received_nonce.ptr);
 452
 453         if (this->diffie_hellman != NULL)
 454         {
 455                 this->diffie_hellman->destroy(this->diffie_hellman);
 456         }
 457         allocator_free(this);
 458 }
 459
 460 /**
 461  * Implements private_responder_init_t.destroy_after_state_change
 462  */
 463 static void destroy_after_state_change (private_responder_init_t *this)
 464 {
 465         this->logger->log(this->logger, CONTROL | MORE, "Going to destroy responder_init_t state object");
 466
 467         /* destroy stored proposal */
 468         this->logger->log(this->logger, CONTROL | MOST, "Destroy stored proposals");
 469
 470         /* destroy diffie hellman object */
 471         if (this->diffie_hellman != NULL)
 472         {
 473                 this->logger->log(this->logger, CONTROL | MOST, "Destroy diffie_hellman_t object");
 474                 this->diffie_hellman->destroy(this->diffie_hellman);
 475         }
 476
 477         allocator_free(this);
 478 }
 479
 480 /*
 481  * Described in header.
 482  */
 483 responder_init_t *responder_init_create(protected_ike_sa_t *ike_sa)
 484 {
 485         private_responder_init_t *this = allocator_alloc_thing(private_responder_init_t);
 486
 487         /* interface functions */
 488         this->public.state_interface.process_message = (status_t (*) (state_t *,message_t *)) process_message;
 489         this->public.state_interface.get_state = (ike_sa_state_t (*) (state_t *)) get_state;
 490         this->public.state_interface.destroy  = (void (*) (state_t *)) destroy;
 491
 492         /* private functions */
 493         this->build_sa_payload = build_sa_payload;
 494         this->build_ke_payload = build_ke_payload;
 495         this->build_nonce_payload = build_nonce_payload;
 496         this->destroy_after_state_change = destroy_after_state_change;
 497
 498         /* private data */
 499         this->ike_sa = ike_sa;
 500         this->logger = this->ike_sa->get_logger(this->ike_sa);
 501         this->sent_nonce = CHUNK_INITIALIZER;
 502         this->received_nonce = CHUNK_INITIALIZER;
 503
 504         return &(this->public);
 505 }