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
  31
  32 typedef struct private_ike_rekey_t private_ike_rekey_t;
  33
  34 /**
  35  * Private members of a ike_rekey_t task.
  36  */
  37 struct private_ike_rekey_t {
  38
  39         /**
  40          * Public methods and task_t interface.
  41          */
  42         ike_rekey_t public;
  43
  44         /**
  45          * Assigned IKE_SA.
  46          */
  47         ike_sa_t *ike_sa;
  48
  49         /**
  50          * New IKE_SA which replaces the current one
  51          */
  52         ike_sa_t *new_sa;
  53
  54         /**
  55          * Are we the initiator?
  56          */
  57         bool initiator;
  58
  59         /**
  60          * the IKE_INIT task which is reused to simplify rekeying
  61          */
  62         ike_init_t *ike_init;
  63
  64         /**
  65          * colliding task detected by the task manager
  66          */
  67         task_t *collision;
  68 };
  69
  70 /**
  71  * Implementation of task_t.build for initiator
  72  */
  73 static status_t build_i(private_ike_rekey_t *this, message_t *message)
  74 {
  75         connection_t *connection;
  76         policy_t *policy;
  77         ike_sa_id_t *id;
  78
  79         id = ike_sa_id_create(0, 0, TRUE);
  80         this->new_sa = charon->ike_sa_manager->checkout(charon->ike_sa_manager, id);
  81         id->destroy(id);
  82
  83         connection = this->ike_sa->get_connection(this->ike_sa);
  84         policy = this->ike_sa->get_policy(this->ike_sa);
  85         this->new_sa->set_connection(this->new_sa, connection);
  86         this->new_sa->set_policy(this->new_sa, policy);
  87
  88         this->ike_init = ike_init_create(this->new_sa, TRUE, this->ike_sa);
  89         this->ike_init->task.build(&this->ike_init->task, message);
  90
  91         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
  92
  93         return NEED_MORE;
  94 }
  95
  96 /**
  97  * Implementation of task_t.process for initiator
  98  */
  99 static status_t process_r(private_ike_rekey_t *this, message_t *message)
 100 {
 101         connection_t *connection;
 102         policy_t *policy;
 103         ike_sa_id_t *id;
 104         iterator_t *iterator;
 105         child_sa_t *child_sa;
 106
 107         if (this->ike_sa->get_state(this->ike_sa) == IKE_DELETING)
 108         {
 109                 DBG1(DBG_IKE, "peer initiated rekeying, but we are deleting");
 110                 return NEED_MORE;
 111         }
 112
 113         iterator = this->ike_sa->create_child_sa_iterator(this->ike_sa);
 114         while (iterator->iterate(iterator, (void**)&child_sa))
 115         {
 116                 switch (child_sa->get_state(child_sa))
 117                 {
 118                         case CHILD_CREATED:
 119                         case CHILD_REKEYING:
 120                         case CHILD_DELETING:
 121                                 /* we do not allow rekeying while we have children in-progress */
 122                                 DBG1(DBG_IKE, "peer initiated rekeying, but a child is half-open");
 123                                 iterator->destroy(iterator);
 124                                 return NEED_MORE;
 125                         default:
 126                                 break;
 127                 }
 128         }
 129         iterator->destroy(iterator);
 130
 131         id = ike_sa_id_create(0, 0, FALSE);
 132         this->new_sa = charon->ike_sa_manager->checkout(charon->ike_sa_manager, id);
 133         id->destroy(id);
 134
 135         connection = this->ike_sa->get_connection(this->ike_sa);
 136         policy = this->ike_sa->get_policy(this->ike_sa);
 137         this->new_sa->set_connection(this->new_sa, connection);
 138         this->new_sa->set_policy(this->new_sa, policy);
 139
 140         this->ike_init = ike_init_create(this->new_sa, FALSE, this->ike_sa);
 141         this->ike_init->task.process(&this->ike_init->task, message);
 142
 143         return NEED_MORE;
 144 }
 145
 146 /**
 147  * Implementation of task_t.build for responder
 148  */
 149 static status_t build_r(private_ike_rekey_t *this, message_t *message)
 150 {
 151         if (this->new_sa == NULL)
 152         {
 153                 /* IKE_SA/a CHILD_SA is in an inacceptable state, deny rekeying */
 154                 message->add_notify(message, TRUE, NO_PROPOSAL_CHOSEN, chunk_empty);
 155                 return SUCCESS;
 156         }
 157
 158         if (this->ike_init->task.build(&this->ike_init->task, message) == FAILED)
 159         {
 160                 return SUCCESS;
 161         }
 162
 163         this->ike_sa->set_state(this->ike_sa, IKE_REKEYING);
 164         this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
 165
 166         return SUCCESS;
 167 }
 168
 169 /**
 170  * Implementation of task_t.process for initiator
 171  */
 172 static status_t process_i(private_ike_rekey_t *this, message_t *message)
 173 {
 174         job_t *job;
 175         ike_sa_id_t *to_delete;
 176
 177         if (this->ike_init->task.process(&this->ike_init->task, message) == FAILED)
 178         {
 179                 /* rekeying failed, fallback to old SA */
 180                 if (!(this->collision &&
 181                         this->collision->get_type(this->collision) == IKE_DELETE))
 182                 {
 183                         this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 184                         /* TODO: reschedule rekeying */
 185                 }
 186                 return SUCCESS;
 187         }
 188
 189         this->new_sa->set_state(this->new_sa, IKE_ESTABLISHED);
 190         to_delete = this->ike_sa->get_id(this->ike_sa);
 191
 192         /* check for collisions */
 193         if (this->collision &&
 194                 this->collision->get_type(this->collision) == IKE_REKEY)
 195         {
 196                 chunk_t this_nonce, other_nonce;
 197                 host_t *host;
 198                 private_ike_rekey_t *other = (private_ike_rekey_t*)this->collision;
 199
 200                 this_nonce = this->ike_init->get_lower_nonce(this->ike_init);
 201                 other_nonce = other->ike_init->get_lower_nonce(other->ike_init);
 202
 203                 /* if we have the lower nonce, delete rekeyed SA. If not, delete
 204                  * the redundant. */
 205                 if (memcmp(this_nonce.ptr, other_nonce.ptr,
 206                                    min(this_nonce.len, other_nonce.len)) < 0)
 207                 {
 208                         DBG1(DBG_IKE, "IKE_SA rekey collision won, deleting rekeyed IKE_SA");
 209                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, other->new_sa);
 210                 }
 211                 else
 212                 {
 213                         DBG1(DBG_IKE, "IKE_SA rekey collision lost, deleting redundant IKE_SA");
 214                         /* apply host for a proper delete */
 215                         host = this->ike_sa->get_my_host(this->ike_sa);
 216                         this->new_sa->set_my_host(this->new_sa, host->clone(host));
 217                         host = this->ike_sa->get_other_host(this->ike_sa);
 218                         this->new_sa->set_other_host(this->new_sa, host->clone(host));
 219                         this->ike_sa->set_state(this->ike_sa, IKE_ESTABLISHED);
 220                         to_delete = this->new_sa->get_id(this->new_sa);
 221                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
 222                         /* inherit to other->new_sa in destroy() */
 223                         this->new_sa = other->new_sa;
 224                         other->new_sa = NULL;
 225                 }
 226         }
 227
 228         job = (job_t*)delete_ike_sa_job_create(to_delete, TRUE);
 229         charon->job_queue->add(charon->job_queue, job);
 230
 231         return SUCCESS;
 232 }
 233
 234 /**
 235  * Implementation of task_t.get_type
 236  */
 237 static task_type_t get_type(private_ike_rekey_t *this)
 238 {
 239         return IKE_REKEY;
 240 }
 241
 242 static void collide(private_ike_rekey_t* this, task_t *other)
 243 {
 244         DESTROY_IF(this->collision);
 245         this->collision = other;
 246 }
 247
 248 /**
 249  * Implementation of task_t.migrate
 250  */
 251 static void migrate(private_ike_rekey_t *this, ike_sa_t *ike_sa)
 252 {
 253         if (this->ike_init)
 254         {
 255                 this->ike_init->task.destroy(&this->ike_init->task);
 256         }
 257         if (this->new_sa)
 258         {
 259                 charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
 260                                                                                                         this->new_sa);
 261         }
 262         DESTROY_IF(this->collision);
 263
 264         this->collision = NULL;
 265         this->ike_sa = ike_sa;
 266         this->new_sa = NULL;
 267         this->ike_init = NULL;
 268 }
 269
 270 /**
 271  * Implementation of task_t.destroy
 272  */
 273 static void destroy(private_ike_rekey_t *this)
 274 {
 275         if (this->new_sa)
 276         {
 277                 if (this->new_sa->get_state(this->new_sa) == IKE_ESTABLISHED)
 278                 {
 279                         this->new_sa->inherit(this->new_sa, this->ike_sa);
 280                         charon->ike_sa_manager->checkin(charon->ike_sa_manager, this->new_sa);
 281                 }
 282                 else
 283                 {
 284                         charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
 285                                                                                                                 this->new_sa);
 286                 }
 287         }
 288         if (this->ike_init)
 289         {
 290                 this->ike_init->task.destroy(&this->ike_init->task);
 291         }
 292         DESTROY_IF(this->collision);
 293         free(this);
 294 }
 295
 296 /*
 297  * Described in header.
 298  */
 299 ike_rekey_t *ike_rekey_create(ike_sa_t *ike_sa, bool initiator)
 300 {
 301         private_ike_rekey_t *this = malloc_thing(private_ike_rekey_t);
 302
 303         this->public.collide = (void(*)(ike_rekey_t*,task_t*))collide;
 304         this->public.task.get_type = (task_type_t(*)(task_t*))get_type;
 305         this->public.task.migrate = (void(*)(task_t*,ike_sa_t*))migrate;
 306         this->public.task.destroy = (void(*)(task_t*))destroy;
 307         if (initiator)
 308         {
 309                 this->public.task.build = (status_t(*)(task_t*,message_t*))build_i;
 310                 this->public.task.process = (status_t(*)(task_t*,message_t*))process_i;
 311         }
 312         else
 313         {
 314                 this->public.task.build = (status_t(*)(task_t*,message_t*))build_r;
 315                 this->public.task.process = (status_t(*)(task_t*,message_t*))process_r;
 316         }
 317
 318         this->ike_sa = ike_sa;
 319         this->new_sa = NULL;
 320         this->ike_init = NULL;
 321         this->initiator = initiator;
 322         this->collision = NULL;
 323
 324         return &this->public;
 325 }