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 <encoding/payloads/notify_payload.h>
  33 #include <transforms/diffie_hellman.h>
  34
  35
  36 typedef struct private_responder_init_t private_responder_init_t;
  37
  38 /**
  39  * Private data of a responder_init_t object.
  40  *
  41  */
  42 struct private_responder_init_t {
  43         /**
  44          * Methods of the state_t interface.
  45          */
  46         responder_init_t public;
  47
  48         /**
  49          * Assigned IKE_SA.
  50          */
  51         protected_ike_sa_t *ike_sa;
  52
  53         /**
  54          * Diffie Hellman object used to compute shared secret.
  55          *
  56          * After processing of incoming IKE_SA_INIT-Request the shared key is
  57          * passed to the next state of type ike_sa_init_responded_t.
  58          */
  59         diffie_hellman_t *diffie_hellman;
  60
  61         /**
  62          * Diffie Hellman group number.
  63          */
  64         u_int16_t dh_group_number;
  65
  66         /**
  67          * Priority used to get matching dh_group number.
  68          */
  69         u_int16_t dh_group_priority;
  70
  71         /**
  72          * Sent nonce value.
  73          *
  74          * This value is passed to the next state of type ike_sa_init_responded_t.
  75          */
  76         chunk_t sent_nonce;
  77
  78         /**
  79          * Received nonce value
  80          *
  81          * This value is passed to the next state of type ike_sa_init_responded_t.
  82          */
  83         chunk_t received_nonce;
  84
  85         /**
  86          * Logger used to log data
  87          *
  88          * Is logger of ike_sa!
  89          */
  90         logger_t *logger;
  91
  92         /**
  93          * Selected proposal from suggested ones.
  94          */
  95         ike_proposal_t selected_proposal;
  96
  97         /**
  98          * Builds the IKE_SA_INIT reply message
  99          *
 100          * @param this          calling object
 101          * @param message       the message will be written to this location.
 102          */
 103         void (*build_ike_sa_init_reply) (private_responder_init_t *this, message_t **message);
 104
 105         /**
 106          * Builds the SA payload for this state.
 107          *
 108          * @param this          calling object
 109          * @param payload       The generated SA payload object of type ke_payload_t is
 110          *                                      stored at this location.
 111          */
 112         void (*build_sa_payload) (private_responder_init_t *this, payload_t **payload);
 113
 114         /**
 115          * Builds the KE payload for this state.
 116          *
 117          * @param this          calling object
 118          * @param payload       The generated KE payload object of type ke_payload_t is
 119          *                                      stored at this location.
 120          */
 121         void (*build_ke_payload) (private_responder_init_t *this, payload_t **payload);
 122
 123         /**
 124          * Builds the NONCE payload for this state.
 125          *
 126          * @param this          calling object
 127          * @param payload       The generated NONCE payload object of type ke_payload_t is
 128          *                                      stored at this location.
 129          */
 130         void (*build_nonce_payload) (private_responder_init_t *this, payload_t **payload);
 131
 132         /**
 133          * Destroy function called internally of this class after state change succeeded.
 134          *
 135          * This destroy function does not destroy objects which were passed to the new state.
 136          *
 137          * @param this          calling object
 138          */
 139         void (*destroy_after_state_change) (private_responder_init_t *this);
 140
 141         /**
 142          * Sends a IKE_SA_INIT reply with a notify payload.
 143          *
 144          * @param this          calling object
 145          * @param type          type of notify message
 146          * @param data          data of notify message
 147          */
 148         void (*send_notify_reply) (private_responder_init_t *this,notify_message_type_t type, chunk_t data);
 149
 150 };
 151
 152 /**
 153  * Implements state_t.get_state
 154  */
 155 static status_t process_message(private_responder_init_t *this, message_t *message)
 156 {
 157         ike_sa_init_responded_t *next_state;
 158         exchange_type_t exchange_type;
 159         host_t *source, *destination;
 160         init_config_t *init_config;
 161         randomizer_t *randomizer;
 162         chunk_t shared_secret;
 163         iterator_t *payloads;
 164         message_t *response;
 165         host_t *other_host;
 166         packet_t *packet;
 167         host_t *my_host;
 168         status_t status;
 169
 170         exchange_type = message->get_exchange_type(message);
 171         if (exchange_type != IKE_SA_INIT)
 172         {
 173                 this->logger->log(this->logger, ERROR | MORE, "Message of type %s not supported in state responder_init",mapping_find(exchange_type_m,exchange_type));
 174                 return DELETE_ME;
 175         }
 176         if (!message->get_request(message))
 177         {
 178                 this->logger->log(this->logger, ERROR | MORE, "Only requests of type IKE_SA_INIT supported in state responder_init");
 179                 return DELETE_ME;
 180         }
 181         /* this is the first message we process, so get host infos */
 182         source = message->get_source(message);
 183         destination = message->get_destination(message);
 184
 185         status = charon->configuration_manager->get_init_config_for_host(charon->configuration_manager,destination,source,&init_config);
 186         if (status != SUCCESS)
 187         {
 188                 /* no configuration matches given host */
 189                 this->logger->log(this->logger, ERROR | MORE, "No INIT configuration found for given remote and local hosts");
 190                 return DELETE_ME;
 191         }
 192
 193         this->ike_sa->set_init_config(this->ike_sa,init_config);
 194
 195         /* we need to clone them, since we destroy the message later */
 196         my_host = destination->clone(destination);
 197         other_host = source->clone(source);
 198
 199         this->ike_sa->set_my_host(this->ike_sa, my_host);
 200         this->ike_sa->set_other_host(this->ike_sa, other_host);
 201
 202         /* parse incoming message */
 203         status = message->parse_body(message, NULL, NULL);
 204         if (status != SUCCESS)
 205         {
 206                 this->logger->log(this->logger, ERROR | MORE, "Could not parse body of request message");
 207                 return DELETE_ME;
 208         }
 209
 210         /* iterate over incoming payloads. We can be sure, the message contains only accepted payloads! */
 211         payloads = message->get_payload_iterator(message);
 212
 213         while (payloads->has_next(payloads))
 214         {
 215                 payload_t *payload;
 216
 217                 /* get current payload */
 218                 payloads->current(payloads, (void**)&payload);
 219
 220                 this->logger->log(this->logger, CONTROL|MORE, "Processing payload of type %s", mapping_find(payload_type_m, payload->get_type(payload)));
 221                 switch (payload->get_type(payload))
 222                 {
 223                         case SECURITY_ASSOCIATION:
 224                         {
 225                                 sa_payload_t *sa_payload = (sa_payload_t*)payload;
 226                                 ike_proposal_t *ike_proposals;
 227                                 size_t proposal_count;
 228
 229                                 /* get the list of suggested proposals */
 230                                 status = sa_payload->get_ike_proposals (sa_payload, &ike_proposals,&proposal_count);
 231                                 if (status != SUCCESS)
 232                                 {
 233                                         this->logger->log(this->logger, ERROR | MORE, "SA payload does not contain IKE proposals");
 234                                         payloads->destroy(payloads);
 235                                         return DELETE_ME;
 236                                 }
 237
 238                                 status = init_config->select_proposal(init_config, ike_proposals,proposal_count,&(this->selected_proposal));
 239                                 allocator_free(ike_proposals);
 240                                 if (status != SUCCESS)
 241                                 {
 242                                         this->logger->log(this->logger, ERROR | MORE, "No proposal of suggested proposals selected");
 243                                         payloads->destroy(payloads);
 244                                         this->send_notify_reply(this,NO_PROPOSAL_CHOSEN,CHUNK_INITIALIZER);
 245                                         return DELETE_ME;
 246                                 }
 247
 248                                 this->dh_group_number = this->selected_proposal.diffie_hellman_group;
 249
 250                                 status = this->ike_sa->create_transforms_from_proposal(this->ike_sa,&(this->selected_proposal));
 251                                 if (status != SUCCESS)
 252                                 {
 253                                         this->logger->log(this->logger, ERROR | MORE, "Transform objects could not be created from selected proposal");
 254                                         payloads->destroy(payloads);
 255                                         return DELETE_ME;
 256                                 }
 257
 258                                 this->logger->log(this->logger, CONTROL | MORE, "SA Payload processed");
 259                                 /* ok, we have what we need for sa_payload (proposals are stored in this->proposals)*/
 260                                 break;
 261                         }
 262                         case KEY_EXCHANGE:
 263                         {
 264                                 ke_payload_t *ke_payload = (ke_payload_t*)payload;
 265                                 diffie_hellman_group_t group;
 266                                 diffie_hellman_t *dh;
 267
 268                                 group = ke_payload->get_dh_group_number(ke_payload);
 269
 270                                 if (group == MODP_UNDEFINED)
 271                                 {
 272                                         this->logger->log(this->logger, ERROR | MORE, "Diffie hellman group set to undefined!");
 273                                         payloads->destroy(payloads);
 274                                         return DELETE_ME;
 275                                 }
 276                                 if (this->dh_group_number != group)
 277                                 {
 278                                         u_int16_t accepted_group;
 279                                         chunk_t accepted_group_chunk;
 280                                         /* group not same as selected one
 281                                          * Maybe key exchange payload is before SA payload */
 282                                         this->logger->log(this->logger, ERROR | MORE, "Diffie hellman group not as in selected proposal!");
 283                                         payloads->destroy(payloads);
 284
 285                                         accepted_group = htons(this->dh_group_number);
 286                                         accepted_group_chunk.ptr = (u_int8_t*) &(accepted_group);
 287                                         accepted_group_chunk.len = 2;
 288                                         this->send_notify_reply(this,INVALID_KE_PAYLOAD,accepted_group_chunk);
 289                                         return DELETE_ME;
 290                                 }
 291
 292                                 /* create diffie hellman object to handle DH exchange */
 293                                 dh = diffie_hellman_create(group);
 294                                 if (dh == NULL)
 295                                 {
 296                                         this->logger->log(this->logger, ERROR, "Could not generate DH object with group %d",mapping_find(diffie_hellman_group_m,group) );
 297                                         payloads->destroy(payloads);
 298                                         return DELETE_ME;
 299                                 }
 300                                 this->logger->log(this->logger, CONTROL | MORE, "Set other DH public value");
 301
 302                                 dh->set_other_public_value(dh, ke_payload->get_key_exchange_data(ke_payload));
 303
 304                                 this->diffie_hellman = dh;
 305
 306                                 this->logger->log(this->logger, CONTROL | MORE, "KE Payload processed.");
 307                                 break;
 308                         }
 309                         case NONCE:
 310                         {
 311                                 nonce_payload_t *nonce_payload = (nonce_payload_t*)payload;
 312
 313                                 allocator_free(this->received_nonce.ptr);
 314                                 this->received_nonce = CHUNK_INITIALIZER;
 315
 316                                 this->logger->log(this->logger, CONTROL | MORE, "Get nonce value and store it");
 317                                 nonce_payload->get_nonce(nonce_payload, &(this->received_nonce));
 318
 319                                 this->logger->log(this->logger, CONTROL | MORE, "Nonce Payload processed");
 320                                 break;
 321                         }
 322                         default:
 323                         {
 324                                 this->logger->log(this->logger, ERROR | MORE, "Payload type not supported!");
 325                                 payloads->destroy(payloads);
 326                                 return DELETE_ME;
 327                         }
 328                 }
 329         }
 330         /* iterator can be destroyed */
 331         payloads->destroy(payloads);
 332
 333         this->logger->log(this->logger, CONTROL | MORE, "Request successfully handled. Going to create reply.");
 334
 335         this->logger->log(this->logger, CONTROL | MOST, "Going to create nonce.");
 336
 337         randomizer = this->ike_sa->get_randomizer(this->ike_sa);
 338         randomizer->allocate_pseudo_random_bytes(randomizer, NONCE_SIZE, &(this->sent_nonce));
 339
 340         /* store shared secret  */
 341         this->logger->log(this->logger, CONTROL | MOST, "Retrieve shared secret and store it.");
 342         status = this->diffie_hellman->get_shared_secret(this->diffie_hellman, &shared_secret);
 343         this->logger->log_chunk(this->logger, PRIVATE, "Shared secret", &shared_secret);
 344
 345         this->ike_sa->compute_secrets(this->ike_sa,shared_secret,this->received_nonce, this->sent_nonce);
 346
 347         this->build_ike_sa_init_reply(this,&response);
 348
 349         /* generate packet */
 350         this->logger->log(this->logger, CONTROL|MOST, "generate packet from message");
 351         status = response->generate(response, NULL, NULL, &packet);
 352         if (status != SUCCESS)
 353         {
 354                 this->logger->log(this->logger, ERROR, "could not generate packet from message");
 355                 return DELETE_ME;
 356         }
 357
 358         this->logger->log(this->logger, CONTROL|MOST, "Add packet to global send queue");
 359          charon->send_queue->add(charon->send_queue, packet);
 360
 361         /* state can now be changed */
 362         this->logger->log(this->logger, CONTROL|MOST, "Create next state object");
 363
 364         next_state = ike_sa_init_responded_create(this->ike_sa, shared_secret, this->received_nonce, this->sent_nonce);
 365
 366         /* last message can now be set */
 367         status = this->ike_sa->set_last_responded_message(this->ike_sa, response);
 368
 369         if (status != SUCCESS)
 370         {
 371                 this->logger->log(this->logger, ERROR, "Could not set last responded message");
 372                 response->destroy(response);
 373                 (next_state->state_interface).destroy(&(next_state->state_interface));
 374                 return DELETE_ME;
 375         }
 376
 377         /* state can now be changed */
 378         this->ike_sa->set_new_state(this->ike_sa, (state_t *) next_state);
 379         /* state has NOW changed :-) */
 380         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) );
 381
 382         this->logger->log(this->logger, CONTROL|MOST, "Destroy old sate object");
 383         this->destroy_after_state_change(this);
 384
 385         return SUCCESS;
 386 }
 387
 388
 389 /**
 390  * implements private_responder_init_t.build_ike_sa_init_reply
 391  */
 392 static void build_ike_sa_init_reply (private_responder_init_t *this, message_t **message)
 393 {
 394         message_t *response;
 395         payload_t *payload;
 396
 397         this->logger->log(this->logger, CONTROL|MOST, "Going to build message");
 398         /* set up the reply */
 399         this->ike_sa->build_message(this->ike_sa, IKE_SA_INIT, FALSE, &response);
 400
 401         /* build SA payload */
 402         this->build_sa_payload(this, &payload);
 403         this->logger->log(this->logger, CONTROL|MOST, "add SA payload to message");
 404         response->add_payload(response, payload);
 405
 406         /* build KE payload */
 407         this->build_ke_payload(this,&payload);
 408         this->logger->log(this->logger, CONTROL|MOST, "add KE payload to message");
 409         response->add_payload(response, payload);
 410
 411         /* build Nonce payload */
 412         this->build_nonce_payload(this, &payload);
 413         this->logger->log(this->logger, CONTROL|MOST, "add nonce payload to message");
 414         response->add_payload(response, payload);
 415
 416         *message = response;
 417 }
 418
 419 /**
 420  * implements private_initiator_init_t.build_sa_payload
 421  */
 422 static void build_sa_payload(private_responder_init_t *this, payload_t **payload)
 423 {
 424         sa_payload_t* sa_payload;
 425
 426         this->logger->log(this->logger, CONTROL|MORE, "building sa payload");
 427         sa_payload = sa_payload_create_from_ike_proposals(&(this->selected_proposal),1);
 428
 429         *payload = (payload_t *) sa_payload;
 430 }
 431
 432 /**
 433  * implements private_initiator_init_t.build_ke_payload
 434  */
 435 static void build_ke_payload(private_responder_init_t *this, payload_t **payload)
 436 {
 437         ke_payload_t *ke_payload;
 438         chunk_t key_data;
 439
 440         this->logger->log(this->logger, CONTROL|MORE, "building ke payload");
 441         this->diffie_hellman->get_my_public_value(this->diffie_hellman,&key_data);
 442
 443         ke_payload = ke_payload_create();
 444         ke_payload->set_key_exchange_data(ke_payload,key_data);
 445         ke_payload->set_dh_group_number(ke_payload, this->dh_group_number);
 446         allocator_free_chunk(&key_data);
 447
 448         *payload = (payload_t *) ke_payload;
 449 }
 450
 451 /**
 452  * implements private_initiator_init_t.build_nonce_payload
 453  */
 454 static void build_nonce_payload(private_responder_init_t *this, payload_t **payload)
 455 {
 456         nonce_payload_t *nonce_payload;
 457
 458         this->logger->log(this->logger, CONTROL|MORE, "building nonce payload");
 459         nonce_payload = nonce_payload_create();
 460         nonce_payload->set_nonce(nonce_payload, this->sent_nonce);
 461
 462         *payload = (payload_t *) nonce_payload;
 463 }
 464
 465
 466 /**
 467  * Implements state_t.get_state
 468  */
 469 static ike_sa_state_t get_state(private_responder_init_t *this)
 470 {
 471         return RESPONDER_INIT;
 472 }
 473
 474 /**
 475  * Implementation of private_initiator_init_t.send_notify_reply.
 476  */
 477 static void send_notify_reply (private_responder_init_t *this,notify_message_type_t type, chunk_t data)
 478 {
 479         notify_payload_t *payload;
 480         message_t *response;
 481         packet_t *packet;
 482         status_t status;
 483
 484         this->logger->log(this->logger, CONTROL|MOST, "Going to build message with notify payload");
 485         /* set up the reply */
 486         this->ike_sa->build_message(this->ike_sa, IKE_SA_INIT, FALSE, &response);
 487         payload = notify_payload_create_from_protocol_and_type(IKE,type);
 488         if ((data.ptr != NULL) && (data.len > 0))
 489         {
 490                 this->logger->log(this->logger, CONTROL|MOST, "Add Data to notify payload");
 491                 payload->set_notification_data(payload,data);
 492         }
 493
 494         this->logger->log(this->logger, CONTROL|MOST, "Add Notify payload to message");
 495         response->add_payload(response,(payload_t *) payload);
 496
 497         /* generate packet */
 498         this->logger->log(this->logger, CONTROL|MOST, "Gnerate packet from message");
 499         status = response->generate(response, NULL, NULL, &packet);
 500         if (status != SUCCESS)
 501         {
 502                 this->logger->log(this->logger, ERROR, "Could not generate packet from message");
 503                 return;
 504         }
 505
 506         this->logger->log(this->logger, CONTROL|MOST, "Add packet to global send queue");
 507         charon->send_queue->add(charon->send_queue, packet);
 508         this->logger->log(this->logger, CONTROL|MOST, "Destroy message");
 509         response->destroy(response);
 510 }
 511
 512 /**
 513  * Implements state_t.get_state
 514  */
 515 static void destroy(private_responder_init_t *this)
 516 {
 517         this->logger->log(this->logger, CONTROL | MORE, "Going to destroy responder init state object");
 518
 519         this->logger->log(this->logger, CONTROL | MOST, "Destroy sent nonce");
 520         allocator_free(this->sent_nonce.ptr);
 521         this->logger->log(this->logger, CONTROL | MOST, "Destroy received nonce");
 522         allocator_free(this->received_nonce.ptr);
 523
 524         if (this->diffie_hellman != NULL)
 525         {
 526                 this->logger->log(this->logger, CONTROL | MOST, "Destroy diffie_hellman_t hellman object");
 527                 this->diffie_hellman->destroy(this->diffie_hellman);
 528         }
 529         this->logger->log(this->logger, CONTROL | MOST, "Destroy object");
 530         allocator_free(this);
 531 }
 532
 533 /**
 534  * Implements private_responder_init_t.destroy_after_state_change
 535  */
 536 static void destroy_after_state_change (private_responder_init_t *this)
 537 {
 538         this->logger->log(this->logger, CONTROL | MORE, "Going to destroy responder_init_t state object");
 539
 540         /* destroy diffie hellman object */
 541         if (this->diffie_hellman != NULL)
 542         {
 543                 this->logger->log(this->logger, CONTROL | MOST, "Destroy diffie_hellman_t object");
 544                 this->diffie_hellman->destroy(this->diffie_hellman);
 545         }
 546
 547         this->logger->log(this->logger, CONTROL | MOST, "Destroy object");
 548         allocator_free(this);
 549 }
 550
 551 /*
 552  * Described in header.
 553  */
 554 responder_init_t *responder_init_create(protected_ike_sa_t *ike_sa)
 555 {
 556         private_responder_init_t *this = allocator_alloc_thing(private_responder_init_t);
 557
 558         /* interface functions */
 559         this->public.state_interface.process_message = (status_t (*) (state_t *,message_t *)) process_message;
 560         this->public.state_interface.get_state = (ike_sa_state_t (*) (state_t *)) get_state;
 561         this->public.state_interface.destroy  = (void (*) (state_t *)) destroy;
 562
 563         /* private functions */
 564         this->build_ike_sa_init_reply = build_ike_sa_init_reply;
 565         this->build_sa_payload = build_sa_payload;
 566         this->build_ke_payload = build_ke_payload;
 567         this->build_nonce_payload = build_nonce_payload;
 568         this->destroy_after_state_change = destroy_after_state_change;
 569         this->send_notify_reply = send_notify_reply;
 570
 571         /* private data */
 572         this->ike_sa = ike_sa;
 573         this->logger = this->ike_sa->get_logger(this->ike_sa);
 574         this->sent_nonce = CHUNK_INITIALIZER;
 575         this->received_nonce = CHUNK_INITIALIZER;
 576         this->dh_group_number = MODP_UNDEFINED;
 577
 578         return &(this->public);
 579 }