src/charon/sa/tasks/ike_rekey.c

   1 /**
   2  * @file ike_rekey.c
   3  *
   4  * @brief Implementation of the ike_rekey task.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005-2007 Martin Willi
  10  * Copyright (C) 2005 Jan Hutter
  11  * Hochschule fuer Technik Rapperswil
  12  *
  13  * This program is free software; you can redistribute it and/or modify it
  14  * under the terms of the GNU General Public License as published by the
  15  * Free Software Foundation; either version 2 of the License, or (at your
  16  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  17  *
  18  * This program is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  20  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  21  * for more details.
  22  */
  23
  24 #include "ike_rekey.h"
  25
  26 #include <daemon.h>
  27 #include <encoding/payloads/notify_payload.h>
  28 #include <sa/tasks/ike_init.h>
  29 #include <queues/jobs/delete_ike_sa_job.h>
  30 #include <queues/jobs/rekey_ike_sa_job.h>
  31
  32
  33 typedef struct private_ike_rekey_t private_ike_rekey_t;
  34
  35 /**
  36  * Private members of a ike_rekey_t task.
  37  */
  38 struct private_ike_rekey_t {
  39
  40         /**
  41          * Public methods and task_t interface.
  42          */
  43         ike_rekey_t public;
  44
  45         /**
  46          * Assigned IKE_SA.
  47          */
  48         ike_sa_t *ike_sa;
  49
  50         /**
  51          * New IKE_SA which replaces the current one
  52          */
  53         ike_sa_t *new_sa;
  54
  55         /**
  56          * Are we the initiator?
  57          */
  58         bool initiator;
  59
  60         /**
  61          * the IKE_INIT task which is reused to simplify rekeying
  62          */
  63         ike_init_t *ike_init;
  64
  65         /**
  66          * colliding task detected by the task manager
  67          */
  68         task_t *collision;
  69 };
  70
  71 /**
  72  * Implementation of task_t.build for initiator
  73  */
  74 static status_t build_i(private_ike_rekey_t *this, message_t *message)
  75 {
  76         connection_t *connection;
  77         policy_t *policy;
  78
  79         this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
  80                                                                                                                 TRUE);
  81
  82         connection = this->ike_sa->get_connection(this->ike_sa);
  83         policy = this->ike_sa->get_policy(this->ike_sa);
  84         this->new_sa->set_connection(this->new_sa, connection);
  85         this->new_sa->set_policy(this->new_sa, policy);
  86
  87         this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
  88         this->ike_init->task.build(&this->ike_init->task, message);
  89
  90         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
  91
  92         return NEED_MORE;
  93 }
  94
  95 /**
  96  * Implementation of task_t.process for initiator
  97  */
  98 static status_t process_r(private_ike_rekey_t *this, message_t *message)
  99 {
 100         connection_t *connection;
 101         policy_t *policy;
 102         iterator_t *iterator;
 103         child_sa_t *child_sa;
 104
 105         if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
 106         {
 107                 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
 108                 return NEED_MORE;
 109         }
 110
 111         iterator = this->ike_sa->create_child_sa_iterator(this->ike_sa);
 112         while (iterator->iterate(iterator, (void**)&child_sa))
 113         {
 114                 switch (child_sa->get_state(child_sa))
 115                 {
 116                         case CHILD_CREATED:
 117                         case CHILD_REKEYING:
 118                         case CHILD_DELETING:
 119                                 /* we do not allow rekeying while we have children in-progress */
 120                                 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
 121                                 iterator->destroy(iterator);
 122                                 return NEED_MORE;
 123                         default:
 124                                 break;
 125                 }
 126         }
 127         iterator->destroy(iterator);
 128
 129         this->new_sa = charon->ike_sa_manager->checkout_new(charon->ike_sa_manager,
 130                                                                                                                 FALSE);
 131
 132         connection = this->ike_sa->get_connection(this->ike_sa);
 133         policy = this->ike_sa->get_policy(this->ike_sa);
 134         this->new_sa->set_connection(this->new_sa, connection);
 135         this->new_sa->set_policy(this->new_sa, policy);
 136
 137         this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
 138         this->ike_init->task.process(&this->ike_init->task, message);
 139
 140         return NEED_MORE;
 141 }
 142
 143 /**
 144  * Implementation of task_t.build for responder
 145  */
 146 static status_t build_r(private_ike_rekey_t *this, message_t *message)
 147 {
 148         if (this->new_sa == NULL)
 149         {
 150                 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
 151                 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
 152                 return SUCCESS;
 153         }
 154
 155         if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
 156         {
 157                 return SUCCESS;
 158         }
 159
 160         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
 161         this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
 162
 163         return SUCCESS;
 164 }
 165
 166 /**
 167  * Implementation of task_t.process for initiator
 168  */
 169 static status_t process_i(private_ike_rekey_t *this, message_t *message)
 170 {
 171         job_t *job;
 172         ike_sa_id_t *to_delete;
 173
 174         if (this->ike_init->task.process(&this->ike_init->task, message) == FAILED)
 175         {
 176                 /* rekeying failed, fallback to old SA */
 177                 if (!(this->collision &&
 178                         this->collision->get_type(this->collision) == IKE_DELETE))
 179                 {
 180                         job_t *job;
 181                         u_int32_t retry = charon->configuration->get_retry_interval(
 182                                                                         charon->configuration);
 183                         job = (job_t*)rekey_ike_sa_job_create(
 184                                                                         this->ike_sa->get_id(this->ike_sa), FALSE);
 185                         DBG1(DBG_IKE, "IKE_SA rekeying failed, "
 186                                                                         "trying again in %d seconds", retry);
 187                         this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 188                         charon->event_queue->add_relative(charon->event_queue, job, retry * 1000);
 189                 }
 190                 return SUCCESS;
 191         }
 192
 193         this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
 194         to_delete = this->ike_sa->get_id(this->ike_sa);
 195
 196         /* check for collisions */
 197         if (this->collision &&
 198                 this->collision->get_type(this->collision) == IKE_REKEY)
 199         {
 200                 chunk_t this_nonce, other_nonce;
 201                 host_t *host;
 202                 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
 203
 204                 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
 205                 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
 206
 207                 /* if we have the lower nonce, delete rekeyed SA. If not, delete
 208                  * the redundant. */
 209                 if (memcmp(this_nonce.ptr, other_nonce.ptr,
 210                                    min(this_nonce.len, other_nonce.len)) < 0)
 211                 {
 212                         DBG1(DBG_IKE, "IKE_SA rekey collision won, deleting rekeyed IKE_SA");
 213                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
 214                 }
 215                 else
 216                 {
 217                         DBG1(DBG_IKE, "IKE_SA rekey collision lost, deleting redundant IKE_SA");
 218                         /* apply host for a proper delete */
 219                         host = this->ike_sa->get_my_host(this->ike_sa);
 220                         this->new_sa->set_my_host(this->new_sa, host->clone(host));
 221                         host = this->ike_sa->get_other_host(this->ike_sa);
 222                         this->new_sa->set_other_host(this->new_sa, host->clone(host));
 223                         this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 224                         to_delete = this->new_sa->get_id(this->new_sa);
 225                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
 226                         /* inherit to other->new_sa in destroy() */
 227                         this->new_sa = other->new_sa;
 228                         other->new_sa = NULL;
 229                 }
 230         }
 231
 232         job = (job_t*)delete_ike_sa_job_create(to_delete, TRUE);
 233         charon->job_queue->add(charon->job_queue, job);
 234
 235         return SUCCESS;
 236 }
 237
 238 /**
 239  * Implementation of task_t.get_type
 240  */
 241 static task_type_t get_type(private_ike_rekey_t *this)
 242 {
 243         return IKE_REKEY;
 244 }
 245
 246 static void collide(private_ike_rekey_t* this, task_t *other)
 247 {
 248         DESTROY_IF(this->collision);
 249         this->collision = other;
 250 }
 251
 252 /**
 253  * Implementation of task_t.migrate
 254  */
 255 static void migrate(private_ike_rekey_t *this, ike_sa_t *ike_sa)
 256 {
 257         if (this->ike_init)
 258         {
 259                 this->ike_init->task.destroy(&this->ike_init->task);
 260         }
 261         if (this->new_sa)
 262         {
 263                 charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
 264                                                                                                         this->new_sa);
 265         }
 266         DESTROY_IF(this->collision);
 267
 268         this->collision = NULL;
 269         this->ike_sa = ike_sa;
 270         this->new_sa = NULL;
 271         this->ike_init = NULL;
 272 }
 273
 274 /**
 275  * Implementation of task_t.destroy
 276  */
 277 static void destroy(private_ike_rekey_t *this)
 278 {
 279         if (this->new_sa)
 280         {
 281                 if (this->new_sa->get_state(this->new_sa) == IKE_ESTABLISHED &&
 282                         this->new_sa->inherit(this->new_sa, this->ike_sa) != DESTROY_ME)
 283                 {
 284                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
 285                 }
 286                 else
 287                 {
 288                         charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
 289                                                                                                                 this->new_sa);
 290                 }
 291         }
 292         if (this->ike_init)
 293         {
 294                 this->ike_init->task.destroy(&this->ike_init->task);
 295         }
 296         DESTROY_IF(this->collision);
 297         free(this);
 298 }
 299
 300 /*
 301  * Described in header.
 302  */
 303 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
 304 {
 305         private_ike_rekey_t *this = malloc_thing(private_ike_rekey_t);
 306
 307         this->public.collide = (void(*)(ike_rekey_t*,task_t*))collide;
 308         this->public.task.get_type = (task_type_t(*)(task_t*))get_type;
 309         this->public.task.migrate = (void(*)(task_t*,ike_sa_t*))migrate;
 310         this->public.task.destroy = (void(*)(task_t*))destroy;
 311         if (initiator)
 312         {
 313                 this->public.task.build = (status_t(*)(task_t*,message_t*))build_i;
 314                 this->public.task.process = (status_t(*)(task_t*,message_t*))process_i;
 315         }
 316         else
 317         {
 318                 this->public.task.build = (status_t(*)(task_t*,message_t*))build_r;
 319                 this->public.task.process = (status_t(*)(task_t*,message_t*))process_r;
 320         }
 321
 322         this->ike_sa = ike_sa;
 323         this->new_sa = NULL;
 324         this->ike_init = NULL;
 325         this->initiator = initiator;
 326         this->collision = NULL;
 327
 328         return &this->public;
 329 }