src/charon/sa/transactions/create_child_sa.c

   1 /**
   2  * @file create_child_sa.c
   3  *
   4  * @brief Implementation of create_child_sa_t transaction.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2006 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 "create_child_sa.h"
  24
  25 #include <string.h>
  26
  27 #include <daemon.h>
  28 #include <encoding/payloads/sa_payload.h>
  29 #include <encoding/payloads/nonce_payload.h>
  30 #include <encoding/payloads/ts_payload.h>
  31 #include <sa/transactions/delete_child_sa.h>
  32 #include <utils/randomizer.h>
  33
  34
  35 typedef struct private_create_child_sa_t private_create_child_sa_t;
  36
  37 /**
  38  * Private members of a create_child_sa_t object..
  39  */
  40 struct private_create_child_sa_t {
  41
  42         /**
  43          * Public methods and transaction_t interface.
  44          */
  45         create_child_sa_t public;
  46
  47         /**
  48          * Assigned IKE_SA.
  49          */
  50         ike_sa_t *ike_sa;
  51
  52         /**
  53          * Message sent by our peer, if already generated
  54          */
  55         message_t *message;
  56
  57         /**
  58          * Message ID this transaction uses
  59          */
  60         u_int32_t message_id;
  61
  62         /**
  63          * Times we did send the request
  64          */
  65         u_int32_t requested;
  66
  67         /**
  68          * initiators inbound SPI of the CHILD_SA which gets rekeyed
  69          */
  70         u_int32_t rekey_spi;
  71
  72         /**
  73          * reqid to use for new CHILD_SA
  74          */
  75         u_int32_t reqid;
  76
  77         /**
  78          * policy definition used
  79          */
  80         policy_t *policy;
  81
  82         /**
  83          * Negotiated proposal used for CHILD_SA
  84          */
  85         proposal_t *proposal;
  86
  87         /**
  88          * initiator chosen nonce
  89          */
  90         chunk_t nonce_i;
  91
  92         /**
  93          * responder chosen nonce
  94          */
  95         chunk_t nonce_r;
  96
  97         /**
  98          * lower of the nonces of a simultaneus rekeying request
  99          */
 100         chunk_t nonce_s;
 101
 102         /**
 103          * Negotiated traffic selectors for initiator
 104          */
 105         linked_list_t *tsi;
 106
 107         /**
 108          * Negotiated traffic selectors for responder
 109          */
 110         linked_list_t *tsr;
 111
 112         /**
 113          * CHILD_SA created by this transaction
 114          */
 115         child_sa_t *child_sa;
 116
 117         /**
 118          * CHILD_SA rekeyed if we are rekeying
 119          */
 120         child_sa_t *rekeyed_sa;
 121
 122         /**
 123          * Have we lost the simultaneous rekeying nonce compare?
 124          */
 125         bool lost;
 126
 127         /**
 128          * source of randomness
 129          */
 130         randomizer_t *randomizer;
 131
 132         /**
 133          * signal to emit when transaction fails. As this transaction is used
 134          * for CHILD_SA creation AND rekeying, we must emit different signals.
 135          */
 136         signal_t failsig;
 137 };
 138
 139 /**
 140  * Implementation of transaction_t.get_message_id.
 141  */
 142 static u_int32_t get_message_id(private_create_child_sa_t *this)
 143 {
 144         return this->message_id;
 145 }
 146
 147 /**
 148  * Implementation of transaction_t.requested.
 149  */
 150 static u_int32_t requested(private_create_child_sa_t *this)
 151 {
 152         return this->requested++;
 153 }
 154
 155 /**
 156  * Implementation of create_child_sa_t.set_policy.
 157  */
 158 static void set_policy(private_create_child_sa_t *this, policy_t *policy)
 159 {
 160         this->policy = policy;
 161 }
 162
 163 /**
 164  * Implementation of create_child_sa_t.set_reqid.
 165  */
 166 static void set_reqid(private_create_child_sa_t *this, u_int32_t reqid)
 167 {
 168         this->reqid = reqid;
 169 }
 170
 171 /**
 172  * Implementation of create_child_sa_t.rekeys_child.
 173  */
 174 static void rekeys_child(private_create_child_sa_t *this, child_sa_t *child_sa)
 175 {
 176         this->rekeyed_sa = child_sa;
 177         this->failsig = CHILD_REKEY_FAILED;
 178 }
 179
 180 /**
 181  * Implementation of create_child_sa_t.cancel.
 182  */
 183 static void cancel(private_create_child_sa_t *this)
 184 {
 185         this->rekeyed_sa = NULL;
 186         this->lost = TRUE;
 187 }
 188
 189 /**
 190  * Implementation of transaction_t.get_request.
 191  */
 192 static status_t get_request(private_create_child_sa_t *this, message_t **result)
 193 {
 194         message_t *request;
 195         host_t *me, *other;
 196         identification_t *my_id, *other_id;
 197
 198         /* check if we already have built a message (retransmission) */
 199         if (this->message)
 200         {
 201                 *result = this->message;
 202                 return SUCCESS;
 203         }
 204
 205         /* check if we are not already rekeying */
 206         if (this->rekeyed_sa)
 207         {
 208                 SIG(CHILD_REKEY_START, "rekeying CHILD_SA");
 209
 210                 switch (this->rekeyed_sa->get_state(this->rekeyed_sa))
 211                 {
 212                         case CHILD_REKEYING:
 213                                 SIG(CHILD_REKEY_FAILED,
 214                                          "rekeying a CHILD_SA which is already rekeying, aborted");
 215                                 return FAILED;
 216                         case CHILD_DELETING:
 217                                 SIG(CHILD_REKEY_FAILED,
 218                                          "rekeying a CHILD_SA which is deleting, aborted");
 219                                 return FAILED;
 220                         default:
 221                                 break;
 222                 }
 223                 this->rekeyed_sa->set_state(this->rekeyed_sa, CHILD_REKEYING);
 224         }
 225         else
 226         {
 227                 SIG(CHILD_UP_START, "creating CHILD_SA");
 228         }
 229
 230         me = this->ike_sa->get_my_host(this->ike_sa);
 231         other = this->ike_sa->get_other_host(this->ike_sa);
 232         my_id = this->ike_sa->get_my_id(this->ike_sa);
 233         other_id = this->ike_sa->get_other_id(this->ike_sa);
 234
 235         /* build the request */
 236         request = message_create();
 237         request->set_source(request, me->clone(me));
 238         request->set_destination(request, other->clone(other));
 239         request->set_exchange_type(request, CREATE_CHILD_SA);
 240         request->set_request(request, TRUE);
 241         request->set_ike_sa_id(request, this->ike_sa->get_id(this->ike_sa));
 242         *result = request;
 243         this->message = request;
 244
 245         {       /* build SA payload */
 246                 sa_payload_t *sa_payload;
 247                 linked_list_t *proposals;
 248                 bool use_natt;
 249
 250                 /* get a policy, if we are rekeying */
 251                 if (this->rekeyed_sa)
 252                 {
 253                         linked_list_t *my_ts, *other_ts;
 254                         identification_t *my_id, *other_id;
 255
 256                         my_ts = this->rekeyed_sa->get_my_traffic_selectors(this->rekeyed_sa);
 257                         other_ts = this->rekeyed_sa->get_other_traffic_selectors(this->rekeyed_sa);
 258                         my_id = this->ike_sa->get_my_id(this->ike_sa);
 259                         other_id = this->ike_sa->get_other_id(this->ike_sa);
 260
 261                         this->policy = charon->policies->get_policy(charon->policies,
 262                                                                                                                 my_id, other_id,
 263                                                                                                                 my_ts, other_ts,
 264                                                                                                             me, other);
 265
 266                         this->reqid = this->rekeyed_sa->get_reqid(this->rekeyed_sa);
 267
 268                         if (this->policy == NULL)
 269                         {
 270                                 SIG(IKE_REKEY_FAILED, "no policy found to rekey "
 271                                          "CHILD_SA with reqid %d", this->reqid);
 272                                 return FAILED;
 273                         }
 274                 }
 275
 276                 proposals = this->policy->get_proposals(this->policy);
 277                 use_natt = this->ike_sa->is_natt_enabled(this->ike_sa);
 278                 this->child_sa = child_sa_create(this->reqid, me, other, my_id, other_id,
 279                                                         this->policy->get_soft_lifetime(this->policy),
 280                                                         this->policy->get_hard_lifetime(this->policy),
 281                                                         this->policy->get_updown(this->policy),
 282                                                         this->policy->get_hostaccess(this->policy),
 283                                                         use_natt);
 284                 this->child_sa->set_name(this->child_sa, this->policy->get_name(this->policy));
 285                 if (this->child_sa->alloc(this->child_sa, proposals) != SUCCESS)
 286                 {
 287                         SIG(this->failsig, "could not install CHILD_SA, CHILD_SA creation failed");
 288                         return FAILED;
 289                 }
 290                 sa_payload = sa_payload_create_from_proposal_list(proposals);
 291                 proposals->destroy_offset(proposals, offsetof(proposal_t, destroy));
 292                 request->add_payload(request, (payload_t*)sa_payload);
 293         }
 294
 295         {       /* build the NONCE payload for us (initiator) */
 296                 nonce_payload_t *nonce_payload;
 297
 298                 if (this->randomizer->allocate_pseudo_random_bytes(this->randomizer,
 299                         NONCE_SIZE, &this->nonce_i) != SUCCESS)
 300                 {
 301                         SIG(this->failsig, "could not create nonce, CHILD_SA creation failed");
 302                         return FAILED;
 303                 }
 304                 nonce_payload = nonce_payload_create();
 305                 nonce_payload->set_nonce(nonce_payload, this->nonce_i);
 306                 request->add_payload(request, (payload_t*)nonce_payload);
 307         }
 308
 309         {       /* build TSi payload */
 310                 linked_list_t *ts_list;
 311                 ts_payload_t *ts_payload;
 312
 313                 ts_list = this->policy->get_my_traffic_selectors(this->policy, me);
 314                 ts_payload = ts_payload_create_from_traffic_selectors(TRUE, ts_list);
 315                 ts_list->destroy_offset(ts_list, offsetof(traffic_selector_t, destroy));
 316                 request->add_payload(request, (payload_t*)ts_payload);
 317         }
 318
 319         {       /* build TSr payload */
 320                 linked_list_t *ts_list;
 321                 ts_payload_t *ts_payload;
 322
 323                 ts_list = this->policy->get_other_traffic_selectors(this->policy, other);
 324                 ts_payload = ts_payload_create_from_traffic_selectors(FALSE, ts_list);
 325                 ts_list->destroy_offset(ts_list, offsetof(traffic_selector_t, destroy));
 326                 request->add_payload(request, (payload_t*)ts_payload);
 327         }
 328
 329         if (this->rekeyed_sa)
 330         {       /* add REKEY_SA notify if we are rekeying */
 331                 notify_payload_t *notify;
 332                 protocol_id_t protocol;
 333
 334                 protocol = this->rekeyed_sa->get_protocol(this->rekeyed_sa);
 335                 notify = notify_payload_create_from_protocol_and_type(protocol, REKEY_SA);
 336                 notify->set_spi(notify, this->rekeyed_sa->get_spi(this->rekeyed_sa, TRUE));
 337                 request->add_payload(request, (payload_t*)notify);
 338
 339                 /* register us as rekeying to detect multiple rekeying */
 340                 this->rekeyed_sa->set_rekeying_transaction(this->rekeyed_sa, &this->public);
 341         }
 342
 343         this->message_id = this->ike_sa->get_next_message_id(this->ike_sa);
 344         request->set_message_id(request, this->message_id);
 345
 346         return SUCCESS;
 347 }
 348
 349 /**
 350  * Handle all kind of notifys
 351  */
 352 static status_t process_notifys(private_create_child_sa_t *this, notify_payload_t *notify_payload)
 353 {
 354         notify_type_t notify_type = notify_payload->get_notify_type(notify_payload);
 355
 356         DBG2(DBG_IKE, "process notify type %N", notify_type_names, notify_type);
 357
 358         switch (notify_type)
 359         {
 360                 case SINGLE_PAIR_REQUIRED:
 361                 {
 362                         SIG(this->failsig, "received a SINGLE_PAIR_REQUIRED notify");
 363                         return FAILED;
 364                 }
 365                 case TS_UNACCEPTABLE:
 366                 {
 367                         SIG(this->failsig, "received TS_UNACCEPTABLE notify");
 368                         return FAILED;
 369                 }
 370                 case NO_PROPOSAL_CHOSEN:
 371                 {
 372                         SIG(this->failsig, "received NO_PROPOSAL_CHOSEN notify");
 373                         return FAILED;
 374                 }
 375                 case REKEY_SA:
 376                 {
 377                         u_int32_t spi;
 378                         protocol_id_t protocol;
 379
 380                         protocol = notify_payload->get_protocol_id(notify_payload);
 381                         switch (protocol)
 382                         {
 383                                 case PROTO_AH:
 384                                 case PROTO_ESP:
 385                                         spi = notify_payload->get_spi(notify_payload);
 386                                         this->rekeyed_sa = this->ike_sa->get_child_sa(this->ike_sa,
 387                                                                                                                                   protocol, spi,
 388                                                                                                                                   FALSE);
 389                                         this->failsig = CHILD_REKEY_FAILED;
 390                                         break;
 391                                 default:
 392                                         break;
 393                         }
 394                         return SUCCESS;
 395                 }
 396                 default:
 397                 {
 398                         if (notify_type < 16383)
 399                         {
 400                                 SIG(this->failsig, "received %N notify error, CHILD_SA "
 401                                          "creation failed", notify_type_names, notify_type);
 402                                 return FAILED;
 403                         }
 404                         else
 405                         {
 406                                 DBG1(DBG_IKE, "received %N notify, ignored",
 407                                          notify_type_names, notify_type);
 408                                 return SUCCESS;
 409                         }
 410                 }
 411         }
 412 }
 413
 414 /**
 415  * Build a notify message.
 416  */
 417 static void build_notify(notify_type_t type, chunk_t data, message_t *message, bool flush_message)
 418 {
 419         notify_payload_t *notify;
 420
 421         if (flush_message)
 422         {
 423                 payload_t *payload;
 424                 iterator_t *iterator = message->get_payload_iterator(message);
 425                 while (iterator->iterate(iterator, (void**)&payload))
 426                 {
 427                         payload->destroy(payload);
 428                         iterator->remove(iterator);
 429                 }
 430                 iterator->destroy(iterator);
 431         }
 432
 433         notify = notify_payload_create();
 434         notify->set_notify_type(notify, type);
 435         notify->set_notification_data(notify, data);
 436         message->add_payload(message, (payload_t*)notify);
 437 }
 438
 439 /**
 440  * Install a CHILD_SA for usage
 441  */
 442 static status_t install_child_sa(private_create_child_sa_t *this, bool initiator)
 443 {
 444         prf_plus_t *prf_plus;
 445         chunk_t seed;
 446         status_t status;
 447
 448         seed = chunk_alloc(this->nonce_i.len + this->nonce_r.len);
 449         memcpy(seed.ptr, this->nonce_i.ptr, this->nonce_i.len);
 450         memcpy(seed.ptr + this->nonce_i.len, this->nonce_r.ptr, this->nonce_r.len);
 451         prf_plus = prf_plus_create(this->ike_sa->get_child_prf(this->ike_sa), seed);
 452         chunk_free(&seed);
 453
 454         if (initiator)
 455         {
 456                 status = this->child_sa->update(this->child_sa, this->proposal, prf_plus);
 457         }
 458         else
 459         {
 460                 status = this->child_sa->add(this->child_sa, this->proposal, prf_plus);
 461         }
 462         prf_plus->destroy(prf_plus);
 463         if (status != SUCCESS)
 464         {
 465                 return DESTROY_ME;
 466         }
 467         if (initiator)
 468         {
 469                 status = this->child_sa->add_policies(this->child_sa, this->tsi, this->tsr);
 470         }
 471         else
 472         {
 473                 status = this->child_sa->add_policies(this->child_sa, this->tsr, this->tsi);
 474         }
 475         if (status != SUCCESS)
 476         {
 477                 return DESTROY_ME;
 478         }
 479
 480         /* add to IKE_SA, and remove from transaction */
 481         this->child_sa->set_state(this->child_sa, CHILD_INSTALLED);
 482         this->ike_sa->add_child_sa(this->ike_sa, this->child_sa);
 483         this->child_sa = NULL;
 484         return SUCCESS;
 485 }
 486
 487 /**
 488  * Implementation of transaction_t.get_response.
 489  */
 490 static status_t get_response(private_create_child_sa_t *this, message_t *request,
 491                                                          message_t **result, transaction_t **next)
 492 {
 493         host_t *me, *other;
 494         identification_t *my_id, *other_id;
 495         message_t *response;
 496         status_t status;
 497         iterator_t *payloads;
 498         payload_t *payload;
 499         sa_payload_t *sa_request = NULL;
 500         nonce_payload_t *nonce_request = NULL;
 501         ts_payload_t *tsi_request = NULL;
 502         ts_payload_t *tsr_request = NULL;
 503         nonce_payload_t *nonce_response;
 504
 505         /* check if we already have built a response (retransmission) */
 506         if (this->message)
 507         {
 508                 *result = this->message;
 509                 return SUCCESS;
 510         }
 511
 512         me = this->ike_sa->get_my_host(this->ike_sa);
 513         other = this->ike_sa->get_other_host(this->ike_sa);
 514         my_id = this->ike_sa->get_my_id(this->ike_sa);
 515         other_id = this->ike_sa->get_other_id(this->ike_sa);
 516         this->message_id = request->get_message_id(request);
 517
 518         /* set up response */
 519         response = message_create();
 520         response->set_source(response, me->clone(me));
 521         response->set_destination(response, other->clone(other));
 522         response->set_exchange_type(response, CREATE_CHILD_SA);
 523         response->set_request(response, FALSE);
 524         response->set_message_id(response, this->message_id);
 525         response->set_ike_sa_id(response, this->ike_sa->get_id(this->ike_sa));
 526         this->message = response;
 527         *result = response;
 528
 529         /* check message type */
 530         if (request->get_exchange_type(request) != CREATE_CHILD_SA)
 531         {
 532                 DBG1(DBG_IKE, "CREATE_CHILD_SA response of invalid type, aborted");
 533                 return FAILED;
 534         }
 535
 536         /* we do not allow the creation of new CHILDren/rekeying when IKE_SA is
 537          * rekeying */
 538         if (this->ike_sa->get_state(this->ike_sa) == IKE_REKEYING ||
 539                 this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
 540         {
 541                 build_notify(NO_ADDITIONAL_SAS, CHUNK_INITIALIZER, response, TRUE);
 542                 DBG1(DBG_IKE, "unable to create new CHILD_SAs, as rekeying in progress");
 543                 return FAILED;
 544         }
 545
 546         /* Iterate over all payloads. */
 547         payloads = request->get_payload_iterator(request);
 548         while (payloads->iterate(payloads, (void**)&payload))
 549         {
 550                 switch (payload->get_type(payload))
 551                 {
 552                         case SECURITY_ASSOCIATION:
 553                                 sa_request = (sa_payload_t*)payload;
 554                                 break;
 555                         case NONCE:
 556                                 nonce_request = (nonce_payload_t*)payload;
 557                                 break;
 558                         case TRAFFIC_SELECTOR_INITIATOR:
 559                                 tsi_request = (ts_payload_t*)payload;
 560                                 break;
 561                         case TRAFFIC_SELECTOR_RESPONDER:
 562                                 tsr_request = (ts_payload_t*)payload;
 563                                 break;
 564                         case KEY_EXCHANGE:
 565                         {
 566                                 u_int8_t dh_buffer[] = {0x00, 0x00}; /* MODP_NONE */
 567                                 chunk_t group = chunk_from_buf(dh_buffer);
 568                                 build_notify(INVALID_KE_PAYLOAD, group, response, TRUE);
 569                                 DBG1(DBG_IKE, "CREATE_CHILD_SA used PFS, sending INVALID_KE_PAYLOAD");
 570                                 return FAILED;
 571                         }
 572                         case NOTIFY:
 573                         {
 574                                 status = process_notifys(this, (notify_payload_t*)payload);
 575                                 if (status != SUCCESS)
 576                                 {
 577                                         payloads->destroy(payloads);
 578                                         return status;
 579                                 }
 580                                 break;
 581                         }
 582                         default:
 583                         {
 584                                 DBG1(DBG_IKE, "ignoring %N payload",
 585                                          payload_type_names, payload->get_type(payload));
 586                                 break;
 587                         }
 588                 }
 589         }
 590         payloads->destroy(payloads);
 591
 592         /* after processing the notify payloads, we know if this transaction is
 593          * for rekeying or for a new CHILD_SA. We can emit the signals now. */
 594         if (this->rekeyed_sa)
 595         {
 596                 SIG(CHILD_REKEY_START, "rekeying CHILD_SA");
 597         }
 598         else
 599         {
 600                 SIG(CHILD_UP_START, "creating CHILD_SA");
 601         }
 602
 603         /* check if we have all payloads */
 604         if (!(sa_request && nonce_request && tsi_request && tsr_request))
 605         {
 606                 build_notify(INVALID_SYNTAX, CHUNK_INITIALIZER, response, TRUE);
 607                 SIG(this->failsig, "request message incomplete, no CHILD_SA created");
 608                 return FAILED;
 609         }
 610
 611         {       /* process nonce payload */
 612                 this->nonce_i = nonce_request->get_nonce(nonce_request);
 613                 if (this->randomizer->allocate_pseudo_random_bytes(this->randomizer,
 614                         NONCE_SIZE, &this->nonce_r) != SUCCESS)
 615                 {
 616                         build_notify(NO_PROPOSAL_CHOSEN, CHUNK_INITIALIZER, response, TRUE);
 617                         SIG(this->failsig, "nonce generation failed, no CHILD_SA created");
 618                         return FAILED;
 619                 }
 620                 nonce_response = nonce_payload_create();
 621                 nonce_response->set_nonce(nonce_response, this->nonce_r);
 622         }
 623
 624         {       /* get a policy and process traffic selectors */
 625                 identification_t *my_id, *other_id;
 626                 linked_list_t *my_ts, *other_ts;
 627
 628                 my_id = this->ike_sa->get_my_id(this->ike_sa);
 629                 other_id = this->ike_sa->get_other_id(this->ike_sa);
 630
 631                 my_ts = tsr_request->get_traffic_selectors(tsr_request);
 632                 other_ts = tsi_request->get_traffic_selectors(tsi_request);
 633
 634                 this->policy = charon->policies->get_policy(charon->policies,
 635                                                                                                         my_id, other_id,
 636                                                                                                         my_ts, other_ts,
 637                                                                                                     me, other);
 638                 if (this->policy)
 639                 {
 640                         this->tsr = this->policy->select_my_traffic_selectors(this->policy, my_ts, me);
 641                         this->tsi = this->policy->select_other_traffic_selectors(this->policy, other_ts, other);
 642                 }
 643                 my_ts->destroy_offset(my_ts, offsetof(traffic_selector_t, destroy));
 644                 other_ts->destroy_offset(other_ts, offsetof(traffic_selector_t, destroy));
 645
 646                 if (this->policy == NULL)
 647                 {
 648                         SIG(this->failsig, "no acceptable policy found, sending TS_UNACCEPTABLE notify");
 649                         build_notify(TS_UNACCEPTABLE, CHUNK_INITIALIZER, response, TRUE);
 650                         return FAILED;
 651                 }
 652         }
 653
 654         {       /* process SA payload */
 655                 linked_list_t *proposal_list;
 656                 sa_payload_t *sa_response;
 657                 ts_payload_t *ts_response;
 658                 bool use_natt;
 659                 u_int32_t soft_lifetime, hard_lifetime;
 660
 661                 sa_response = sa_payload_create();
 662                 /* get proposals from request, and select one with ours */
 663                 proposal_list = sa_request->get_proposals(sa_request);
 664                 DBG2(DBG_IKE, "selecting proposals:");
 665                 this->proposal = this->policy->select_proposal(this->policy, proposal_list);
 666                 proposal_list->destroy_offset(proposal_list, offsetof(proposal_t, destroy));
 667
 668                 /* do we have a proposal? */
 669                 if (this->proposal == NULL)
 670                 {
 671                         SIG(this->failsig, "CHILD_SA proposals unacceptable, sending NO_PROPOSAL_CHOSEN notify");
 672                         build_notify(NO_PROPOSAL_CHOSEN, CHUNK_INITIALIZER, response, TRUE);
 673                         return FAILED;
 674                 }
 675                 /* do we have traffic selectors? */
 676                 else if (this->tsi->get_count(this->tsi) == 0 || this->tsr->get_count(this->tsr) == 0)
 677                 {
 678                         SIG(this->failsig, "CHILD_SA traffic selectors unacceptable, sending TS_UNACCEPTABLE notify");
 679                         build_notify(TS_UNACCEPTABLE, CHUNK_INITIALIZER, response, TRUE);
 680                         return FAILED;
 681                 }
 682                 else
 683                 {       /* create child sa */
 684                         if (this->rekeyed_sa)
 685                         {
 686                                 this->reqid = this->rekeyed_sa->get_reqid(this->rekeyed_sa);
 687                         }
 688                         soft_lifetime = this->policy->get_soft_lifetime(this->policy);
 689                         hard_lifetime = this->policy->get_hard_lifetime(this->policy);
 690                         use_natt = this->ike_sa->is_natt_enabled(this->ike_sa);
 691                         this->child_sa = child_sa_create(this->reqid, me, other, my_id, other_id,
 692                                                                                          soft_lifetime, hard_lifetime,
 693                                                                                          this->policy->get_updown(this->policy),
 694                                                                                          this->policy->get_hostaccess(this->policy),
 695                                                                                          use_natt);
 696                         this->child_sa->set_name(this->child_sa, this->policy->get_name(this->policy));
 697                         if (install_child_sa(this, FALSE) != SUCCESS)
 698                         {
 699                                 SIG(this->failsig, "installing CHILD_SA failed, sending NO_PROPOSAL_CHOSEN notify");
 700                                 build_notify(NO_PROPOSAL_CHOSEN, CHUNK_INITIALIZER, response, TRUE);
 701                                 return FAILED;
 702                         }
 703                         /* add proposal to sa payload */
 704                         sa_response->add_proposal(sa_response, this->proposal);
 705                 }
 706                 response->add_payload(response, (payload_t*)sa_response);
 707
 708                 /* add nonce/ts payload after sa payload */
 709                 response->add_payload(response, (payload_t *)nonce_response);
 710                 ts_response = ts_payload_create_from_traffic_selectors(TRUE, this->tsi);
 711                 response->add_payload(response, (payload_t*)ts_response);
 712                 ts_response = ts_payload_create_from_traffic_selectors(FALSE, this->tsr);
 713                 response->add_payload(response, (payload_t*)ts_response);
 714         }
 715         /* CHILD_SA successfully created. If another transaction is already rekeying
 716          * this SA, our lower nonce must be registered for a later nonce compare. */
 717         if (this->rekeyed_sa)
 718         {
 719                 private_create_child_sa_t *other;
 720
 721                 other = this->rekeyed_sa->get_rekeying_transaction(this->rekeyed_sa);
 722                 if (other)
 723                 {
 724                         /* store our lower nonce in the simultaneus transaction, it
 725                          * will later compare it against his nonces when it calls conclude().
 726                          */
 727                         if (memcmp(this->nonce_i.ptr, this->nonce_r.ptr,
 728                                 min(this->nonce_i.len, this->nonce_r.len)) < 0)
 729                         {
 730                                 other->nonce_s = chunk_clone(this->nonce_i);
 731                         }
 732                         else
 733                         {
 734                                 other->nonce_s = chunk_clone(this->nonce_r);
 735                         }
 736                 }
 737                 else
 738                 {
 739                         /* we only signal when no other transaction is rekeying */
 740                         SIG(CHILD_REKEY_SUCCESS, "CHILD_SA rekeyed");
 741                 }
 742                 this->rekeyed_sa->set_state(this->rekeyed_sa, CHILD_REKEYING);
 743         }
 744         else
 745         {
 746                 SIG(CHILD_UP_SUCCESS, "CHILD_SA created");
 747         }
 748         return SUCCESS;
 749 }
 750
 751 /**
 752  * Implementation of transaction_t.conclude
 753  */
 754 static status_t conclude(private_create_child_sa_t *this, message_t *response,
 755                                                  transaction_t **next)
 756 {
 757         iterator_t *payloads;
 758         payload_t *payload;
 759         host_t *me, *other;
 760         sa_payload_t *sa_payload = NULL;
 761         nonce_payload_t *nonce_payload = NULL;
 762         ts_payload_t *tsi_payload = NULL;
 763         ts_payload_t *tsr_payload = NULL;
 764         status_t status;
 765         child_sa_t *new_child = NULL;
 766         delete_child_sa_t *delete_child_sa;
 767
 768         /* check message type */
 769         if (response->get_exchange_type(response) != CREATE_CHILD_SA)
 770         {
 771                 SIG(this->failsig, "CREATE_CHILD_SA response of invalid type, aborting");
 772                 return FAILED;
 773         }
 774
 775         me = this->ike_sa->get_my_host(this->ike_sa);
 776         other = this->ike_sa->get_other_host(this->ike_sa);
 777
 778         /* Iterate over all payloads to collect them */
 779         payloads = response->get_payload_iterator(response);
 780         while (payloads->iterate(payloads, (void**)&payload))
 781         {
 782                 switch (payload->get_type(payload))
 783                 {
 784                         case SECURITY_ASSOCIATION:
 785                                 sa_payload = (sa_payload_t*)payload;
 786                                 break;
 787                         case NONCE:
 788                                 nonce_payload = (nonce_payload_t*)payload;
 789                                 break;
 790                         case TRAFFIC_SELECTOR_INITIATOR:
 791                                 tsi_payload = (ts_payload_t*)payload;
 792                                 break;
 793                         case TRAFFIC_SELECTOR_RESPONDER:
 794                                 tsr_payload = (ts_payload_t*)payload;
 795                                 break;
 796                         case NOTIFY:
 797                         {
 798                                 status = process_notifys(this, (notify_payload_t*)payload);
 799                                 if (status != SUCCESS)
 800                                 {
 801                                         payloads->destroy(payloads);
 802                                         return status;
 803                                 }
 804                                 break;
 805                         }
 806                         default:
 807                         {
 808                                 DBG1(DBG_IKE, "ignoring %N payload",
 809                                          payload_type_names, payload->get_type(payload));
 810                                 break;
 811                         }
 812                 }
 813         }
 814         payloads->destroy(payloads);
 815
 816         if (!(sa_payload && nonce_payload && tsi_payload && tsr_payload))
 817         {
 818                 SIG(this->failsig, "response message incomplete, no CHILD_SA built");
 819                 return FAILED;
 820         }
 821
 822         {       /* process NONCE payload  */
 823                 this->nonce_r = nonce_payload->get_nonce(nonce_payload);
 824         }
 825
 826         {       /* process traffic selectors for us */
 827                 linked_list_t *ts_received = tsi_payload->get_traffic_selectors(tsi_payload);
 828                 this->tsi = this->policy->select_my_traffic_selectors(this->policy, ts_received, me);
 829                 ts_received->destroy_offset(ts_received, offsetof(traffic_selector_t, destroy));
 830         }
 831
 832         {       /* process traffic selectors for other */
 833                 linked_list_t *ts_received = tsr_payload->get_traffic_selectors(tsr_payload);
 834                 this->tsr = this->policy->select_other_traffic_selectors(this->policy, ts_received, other);
 835                 ts_received->destroy_offset(ts_received, offsetof(traffic_selector_t, destroy));
 836         }
 837
 838         {       /* process sa payload */
 839                 linked_list_t *proposal_list;
 840
 841                 proposal_list = sa_payload->get_proposals(sa_payload);
 842                 /* we have to re-check here if other's selection is valid */
 843                 this->proposal = this->policy->select_proposal(this->policy, proposal_list);
 844                 proposal_list->destroy_offset(proposal_list, offsetof(proposal_t, destroy));
 845
 846                 /* everything fine to create CHILD? */
 847                 if (this->proposal == NULL ||
 848                         this->tsi->get_count(this->tsi) == 0 ||
 849                         this->tsr->get_count(this->tsr) == 0)
 850                 {
 851                         SIG(this->failsig, "CHILD_SA negotiation failed, no CHILD_SA built");
 852                         return FAILED;
 853                 }
 854                 new_child = this->child_sa;
 855                 if (install_child_sa(this, TRUE) != SUCCESS)
 856                 {
 857                         SIG(this->failsig, "installing CHILD_SA failed, no CHILD_SA built");
 858                         return FAILED;
 859                 }
 860         }
 861         /* CHILD_SA successfully created. If the other peer initiated rekeying
 862          * in the meantime, we detect this by comparing the rekeying_transaction
 863          * of the SA. If it changed, we are not alone. Then we must compare the nonces.
 864          * If no simultaneous rekeying is going on, we just initiate the delete of
 865          * the superseded SA. */
 866         if (this->rekeyed_sa)
 867         {
 868                 /* rekeying finished, update SA status */
 869                 this->rekeyed_sa->set_rekeying_transaction(this->rekeyed_sa, NULL);
 870
 871                 if (this->nonce_s.ptr)
 872                 {       /* simlutaneous rekeying is going on, not so good */
 873                         chunk_t this_lowest;
 874
 875                         /* first get our lowest nonce */
 876                         if (memcmp(this->nonce_i.ptr, this->nonce_r.ptr,
 877                                 min(this->nonce_i.len, this->nonce_r.len)) < 0)
 878                         {
 879                                 this_lowest = this->nonce_i;
 880                         }
 881                         else
 882                         {
 883                                 this_lowest = this->nonce_r;
 884                         }
 885                         /* then compare against other lowest nonce */
 886                         if (memcmp(this_lowest.ptr, this->nonce_s.ptr,
 887                                 min(this_lowest.len, this->nonce_s.len)) < 0)
 888                         {
 889                                 DBG1(DBG_IKE, "detected simultaneous CHILD_SA rekeying, deleting ours");
 890                                 this->lost = TRUE;
 891                         }
 892                         else
 893                         {
 894                                 DBG1(DBG_IKE, "detected simultaneous CHILD_SA rekeying, but ours is preferred");
 895                         }
 896                 }
 897                 /* delete the old SA if we have won the rekeying nonce compare*/
 898                 if (!this->lost)
 899                 {
 900                         delete_child_sa = delete_child_sa_create(this->ike_sa);
 901                         delete_child_sa->set_child_sa(delete_child_sa, this->rekeyed_sa);
 902                         *next = (transaction_t*)delete_child_sa;
 903                 }
 904                 /* we send a rekey SUCCESS signal in any case. If the other transaction
 905                 * detected our transaction, it did not send a signal. We do it for it. */
 906                 SIG(CHILD_REKEY_SUCCESS, "CHILD_SA rekeyed");
 907         }
 908         else
 909         {
 910                 SIG(CHILD_UP_SUCCESS, "CHILD_SA created");
 911         }
 912         if (this->lost)
 913         {
 914                 /* we have lost simlutaneous rekeying, delete the CHILD_SA we just have created */
 915                 delete_child_sa = delete_child_sa_create(this->ike_sa);
 916                 delete_child_sa->set_child_sa(delete_child_sa, new_child);
 917                 *next = (transaction_t*)delete_child_sa;
 918         }
 919         return SUCCESS;
 920 }
 921
 922 /**
 923  * implements transaction_t.destroy
 924  */
 925 static void destroy(private_create_child_sa_t *this)
 926 {
 927         DESTROY_IF(this->message);
 928         DESTROY_IF(this->proposal);
 929         DESTROY_IF(this->child_sa);
 930         DESTROY_IF(this->policy);
 931         this->tsi->destroy_offset(this->tsi, offsetof(traffic_selector_t, destroy));
 932         this->tsr->destroy_offset(this->tsr, offsetof(traffic_selector_t, destroy));
 933         chunk_free(&this->nonce_i);
 934         chunk_free(&this->nonce_r);
 935         chunk_free(&this->nonce_s);
 936         this->randomizer->destroy(this->randomizer);
 937         free(this);
 938 }
 939
 940 /*
 941  * Described in header.
 942  */
 943 create_child_sa_t *create_child_sa_create(ike_sa_t *ike_sa)
 944 {
 945         private_create_child_sa_t *this = malloc_thing(private_create_child_sa_t);
 946
 947         /* transaction interface functions */
 948         this->public.transaction.get_request = (status_t(*)(transaction_t*,message_t**))get_request;
 949         this->public.transaction.get_response = (status_t(*)(transaction_t*,message_t*,message_t**,transaction_t**))get_response;
 950         this->public.transaction.conclude = (status_t(*)(transaction_t*,message_t*,transaction_t**))conclude;
 951         this->public.transaction.get_message_id = (u_int32_t(*)(transaction_t*))get_message_id;
 952         this->public.transaction.requested = (u_int32_t(*)(transaction_t*))requested;
 953         this->public.transaction.destroy = (void(*)(transaction_t*))destroy;
 954
 955         /* public functions */
 956         this->public.set_policy = (void(*)(create_child_sa_t*,policy_t*))set_policy;
 957         this->public.set_reqid = (void(*)(create_child_sa_t*,u_int32_t))set_reqid;
 958         this->public.rekeys_child = (void(*)(create_child_sa_t*,child_sa_t*))rekeys_child;
 959         this->public.cancel = (void(*)(create_child_sa_t*))cancel;
 960
 961         /* private data */
 962         this->ike_sa = ike_sa;
 963         this->message_id = 0;
 964         this->message = NULL;
 965         this->requested = 0;
 966         this->rekey_spi = 0;
 967         this->reqid = 0;
 968         this->nonce_i = CHUNK_INITIALIZER;
 969         this->nonce_r = CHUNK_INITIALIZER;
 970         this->nonce_s = CHUNK_INITIALIZER;
 971         this->child_sa = NULL;
 972         this->rekeyed_sa = NULL;
 973         this->lost = FALSE;
 974         this->proposal = NULL;
 975         this->policy = NULL;
 976         this->tsi = NULL;
 977         this->tsr = NULL;
 978         this->randomizer = randomizer_create();
 979         this->failsig = CHILD_UP_FAILED;
 980
 981         return &this->public;
 982 }