src/modules/rlm_eap/rlm_eap.c

   1 /*
   2  * rlm_eap.c  contains handles that are called from modules.
   3  *
   4  * Version:     $Id$
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  * Copyright 2000-2003,2006  The FreeRADIUS server project
  21  * Copyright 2001  hereUare Communications, Inc. <raghud@hereuare.com>
  22  * Copyright 2003  Alan DeKok <aland@freeradius.org>
  23  */
  24
  25 #include <freeradius-devel/ident.h>
  26 RCSID("$Id$")
  27
  28 #include <freeradius-devel/radiusd.h>
  29 #include <freeradius-devel/modules.h>
  30
  31 #include "rlm_eap.h"
  32
  33 static const CONF_PARSER module_config[] = {
  34         { "default_eap_type", PW_TYPE_STRING_PTR,
  35           offsetof(rlm_eap_t, default_eap_type_name), NULL, "md5" },
  36         { "timer_expire", PW_TYPE_INTEGER,
  37           offsetof(rlm_eap_t, timer_limit), NULL, "60"},
  38         { "ignore_unknown_eap_types", PW_TYPE_BOOLEAN,
  39           offsetof(rlm_eap_t, ignore_unknown_eap_types), NULL, "no" },
  40         { "cisco_accounting_username_bug", PW_TYPE_BOOLEAN,
  41           offsetof(rlm_eap_t, cisco_accounting_username_bug), NULL, "no" },
  42         { "max_sessions", PW_TYPE_INTEGER,
  43           offsetof(rlm_eap_t, max_sessions), NULL, "2048"},
  44
  45         { NULL, -1, 0, NULL, NULL }           /* end the list */
  46 };
  47
  48 /*
  49  * delete all the allocated space by eap module
  50  */
  51 static int eap_detach(void *instance)
  52 {
  53         rlm_eap_t *inst;
  54         int i;
  55
  56         inst = (rlm_eap_t *)instance;
  57
  58         rbtree_free(inst->session_tree);
  59         if (inst->handler_tree) rbtree_free(inst->handler_tree);
  60         inst->session_tree = NULL;
  61         eaplist_free(inst);
  62
  63         for (i = 0; i < PW_EAP_MAX_TYPES; i++) {
  64                 if (inst->types[i]) eaptype_free(inst->types[i]);
  65                 inst->types[i] = NULL;
  66         }
  67
  68         pthread_mutex_destroy(&(inst->session_mutex));
  69
  70         free(inst);
  71
  72         return 0;
  73 }
  74
  75
  76 /*
  77  *      Compare two handlers.
  78  */
  79 static int eap_handler_cmp(const void *a, const void *b)
  80 {
  81         int rcode;
  82         const EAP_HANDLER *one = a;
  83         const EAP_HANDLER *two = b;
  84
  85         if (one->eap_id < two->eap_id) return -1;
  86         if (one->eap_id > two->eap_id) return +1;
  87
  88         rcode = memcmp(one->state, two->state, sizeof(one->state));
  89         if (rcode != 0) return rcode;
  90
  91         /*
  92          *      As of 2.1.8, we don't key off of source IP.  This
  93          *      a NAS to send packets load-balanced (or fail-over)
  94          *      across multiple intermediate proxies, and still have
  95          *      EAP work.
  96          */
  97         if (fr_ipaddr_cmp(&one->src_ipaddr, &two->src_ipaddr) != 0) {
  98                 DEBUG("WARNING: EAP packets are arriving from two different upstream servers.  Has there been a proxy fail-over?");
  99         }
 100
 101         return 0;
 102 }
 103
 104
 105 /*
 106  *      Compare two handler pointers
 107  */
 108 static int eap_handler_ptr_cmp(const void *a, const void *b)
 109 {
 110   return (a - b);
 111 }
 112
 113
 114 /*
 115  * read the config section and load all the eap authentication types present.
 116  */
 117 static int eap_instantiate(CONF_SECTION *cs, void **instance)
 118 {
 119         int             i, eap_type;
 120         int             num_types;
 121         CONF_SECTION    *scs;
 122         rlm_eap_t       *inst;
 123
 124         inst = (rlm_eap_t *) malloc(sizeof(*inst));
 125         if (!inst) {
 126                 return -1;
 127         }
 128         memset(inst, 0, sizeof(*inst));
 129         if (cf_section_parse(cs, inst, module_config) < 0) {
 130                 eap_detach(inst);
 131                 return -1;
 132         }
 133
 134         /*
 135          *      Create our own random pool.
 136          */
 137         for (i = 0; i < 256; i++) {
 138                 inst->rand_pool.randrsl[i] = fr_rand();
 139         }
 140         fr_randinit(&inst->rand_pool, 1);
 141         inst->rand_pool.randcnt = 0;
 142
 143         inst->xlat_name = cf_section_name2(cs);
 144         if (!inst->xlat_name) inst->xlat_name = "EAP";
 145
 146         /* Load all the configured EAP-Types */
 147         num_types = 0;
 148         for(scs=cf_subsection_find_next(cs, NULL, NULL);
 149                 scs != NULL;
 150                 scs=cf_subsection_find_next(cs, scs, NULL)) {
 151
 152                 const char      *auth_type;
 153
 154                 auth_type = cf_section_name1(scs);
 155
 156                 if (!auth_type)  continue;
 157
 158                 eap_type = eaptype_name2type(auth_type);
 159                 if (eap_type < 0) {
 160                         radlog(L_ERR, "rlm_eap: Unknown EAP type %s",
 161                                auth_type);
 162                         eap_detach(inst);
 163                         return -1;
 164                 }
 165
 166 #ifndef HAVE_OPENSSL_SSL_H
 167                 /*
 168                  *      This allows the default configuration to be
 169                  *      shipped with EAP-TLS, etc. enabled.  If the
 170                  *      system doesn't have OpenSSL, they will be
 171                  *      ignored.
 172                  *
 173                  *      If the system does have OpenSSL, then this
 174                  *      code will not be used.  The administrator will
 175                  *      then have to delete the tls,
 176                  *      etc. configurations from eap.conf in order to
 177                  *      have EAP without the TLS types.
 178                  */
 179                 if ((eap_type == PW_EAP_TLS) ||
 180                     (eap_type == PW_EAP_TTLS) ||
 181                     (eap_type == PW_EAP_PEAP)) {
 182                         DEBUG2("Ignoring EAP-Type/%s because we do not have OpenSSL support.", auth_type);
 183                         continue;
 184                 }
 185 #endif
 186
 187                 /*
 188                  *      If we're asked to load TTLS or PEAP, ensure
 189                  *      that we've first loaded TLS.
 190                  */
 191                 if (((eap_type == PW_EAP_TTLS) ||
 192                      (eap_type == PW_EAP_PEAP)) &&
 193                     (inst->types[PW_EAP_TLS] == NULL)) {
 194                         radlog(L_ERR, "rlm_eap: Unable to load EAP-Type/%s, as EAP-Type/TLS is required first.",
 195                                auth_type);
 196                         return -1;
 197                 }
 198
 199                 /*
 200                  *      Load the type.
 201                  */
 202                 if (eaptype_load(&inst->types[eap_type], eap_type, scs) < 0) {
 203                         eap_detach(inst);
 204                         return -1;
 205                 }
 206
 207                 num_types++;    /* successfully loaded one more types */
 208         }
 209
 210         if (num_types == 0) {
 211                 radlog(L_ERR|L_CONS, "rlm_eap: No EAP type configured, module cannot do anything.");
 212                 eap_detach(inst);
 213                 return -1;
 214         }
 215
 216         /*
 217          *      Ensure that the default EAP type is loaded.
 218          */
 219         eap_type = eaptype_name2type(inst->default_eap_type_name);
 220         if (eap_type < 0) {
 221                 radlog(L_ERR|L_CONS, "rlm_eap: Unknown default EAP type %s",
 222                        inst->default_eap_type_name);
 223                 eap_detach(inst);
 224                 return -1;
 225         }
 226
 227         if (inst->types[eap_type] == NULL) {
 228                 radlog(L_ERR|L_CONS, "rlm_eap: No such sub-type for default EAP type %s",
 229                        inst->default_eap_type_name);
 230                 eap_detach(inst);
 231                 return -1;
 232         }
 233         inst->default_eap_type = eap_type; /* save the numerical type */
 234
 235         /*
 236          *      List of sessions are set to NULL by the memset
 237          *      of 'inst', above.
 238          */
 239
 240         /*
 241          *      Lookup sessions in the tree.  We don't free them in
 242          *      the tree, as that's taken care of elsewhere...
 243          */
 244         inst->session_tree = rbtree_create(eap_handler_cmp, NULL, 0);
 245         if (!inst->session_tree) {
 246                 radlog(L_ERR|L_CONS, "rlm_eap: Cannot initialize tree");
 247                 eap_detach(inst);
 248                 return -1;
 249         }
 250
 251         if (fr_debug_flag) {
 252                 inst->handler_tree = rbtree_create(eap_handler_ptr_cmp, NULL, 0);
 253                 if (!inst->handler_tree) {
 254                         radlog(L_ERR|L_CONS, "rlm_eap: Cannot initialize tree");
 255                         eap_detach(inst);
 256                         return -1;
 257                 }
 258         }
 259
 260         pthread_mutex_init(&(inst->session_mutex), NULL);
 261
 262         *instance = inst;
 263         return 0;
 264 }
 265
 266
 267 /*
 268  *      For backwards compatibility.
 269  */
 270 static int eap_authenticate(void *instance, REQUEST *request)
 271 {
 272         rlm_eap_t       *inst;
 273         EAP_HANDLER     *handler;
 274         eap_packet_t    *eap_packet;
 275         int             rcode;
 276
 277         inst = (rlm_eap_t *) instance;
 278
 279         if (!pairfind(request->packet->vps, PW_EAP_MESSAGE, 0)) {
 280                 RDEBUG("ERROR: You set 'Auth-Type = EAP' for a request that does not contain an EAP-Message attribute!");
 281                 return RLM_MODULE_INVALID;
 282         }
 283
 284         /*
 285          *      Get the eap packet  to start with
 286          */
 287         eap_packet = eap_vp2packet(request->packet->vps);
 288         if (eap_packet == NULL) {
 289                 radlog_request(L_ERR, 0, request, "Malformed EAP Message");
 290                 return RLM_MODULE_FAIL;
 291         }
 292
 293         /*
 294          *      Create the eap handler.  The eap_packet will end up being
 295          *      "swallowed" into the handler, so we can't access it after
 296          *      this call.
 297          */
 298         handler = eap_handler(inst, &eap_packet, request);
 299         if (handler == NULL) {
 300                 RDEBUG2("Failed in handler");
 301                 return RLM_MODULE_INVALID;
 302         }
 303
 304         /*
 305          *      Select the appropriate eap_type or default to the
 306          *      configured one
 307          */
 308         rcode = eaptype_select(inst, handler);
 309
 310         /*
 311          *      If it failed, die.
 312          */
 313         if (rcode == EAP_INVALID) {
 314                 eap_fail(handler);
 315                 eap_handler_free(inst, handler);
 316                 RDEBUG2("Failed in EAP select");
 317                 return RLM_MODULE_INVALID;
 318         }
 319
 320 #ifdef WITH_PROXY
 321         /*
 322          *      If we're doing horrible tunneling work, remember it.
 323          */
 324         if ((request->options & RAD_REQUEST_OPTION_PROXY_EAP) != 0) {
 325                 RDEBUG2("  Not-EAP proxy set.  Not composing EAP");
 326                 /*
 327                  *      Add the handle to the proxied list, so that we
 328                  *      can retrieve it in the post-proxy stage, and
 329                  *      send a response.
 330                  */
 331                 rcode = request_data_add(request,
 332                                          inst, REQUEST_DATA_EAP_HANDLER,
 333                                          handler,
 334                                          (void *) eap_handler_free);
 335                 rad_assert(rcode == 0);
 336
 337                 return RLM_MODULE_HANDLED;
 338         }
 339 #endif
 340
 341 #ifdef WITH_PROXY
 342         /*
 343          *      Maybe the request was marked to be proxied.  If so,
 344          *      proxy it.
 345          */
 346         if (request->proxy != NULL) {
 347                 VALUE_PAIR *vp = NULL;
 348
 349                 rad_assert(request->proxy_reply == NULL);
 350
 351                 /*
 352                  *      Add the handle to the proxied list, so that we
 353                  *      can retrieve it in the post-proxy stage, and
 354                  *      send a response.
 355                  */
 356                 rcode = request_data_add(request,
 357                                          inst, REQUEST_DATA_EAP_HANDLER,
 358                                          handler,
 359                                          (void *) eap_handler_free);
 360                 rad_assert(rcode == 0);
 361
 362                 /*
 363                  *      Some simple sanity checks.  These should really
 364                  *      be handled by the radius library...
 365                  */
 366                 vp = pairfind(request->proxy->vps, PW_EAP_MESSAGE, 0);
 367                 if (vp) {
 368                         vp = pairfind(request->proxy->vps, PW_MESSAGE_AUTHENTICATOR, 0);
 369                         if (!vp) {
 370                                 vp = pairmake("Message-Authenticator",
 371                                               "0x00", T_OP_EQ);
 372                                 rad_assert(vp != NULL);
 373                                 pairadd(&(request->proxy->vps), vp);
 374                         }
 375                 }
 376
 377                 /*
 378                  *      Delete the "proxied to" attribute, as it's
 379                  *      set to 127.0.0.1 for tunneled requests, and
 380                  *      we don't want to tell the world that...
 381                  */
 382                 pairdelete(&request->proxy->vps, PW_FREERADIUS_PROXIED_TO, VENDORPEC_FREERADIUS);
 383
 384                 RDEBUG2("  Tunneled session will be proxied.  Not doing EAP.");
 385                 return RLM_MODULE_HANDLED;
 386         }
 387 #endif
 388
 389         /*
 390          *      We are done, wrap the EAP-request in RADIUS to send
 391          *      with all other required radius attributes
 392          */
 393         rcode = eap_compose(handler);
 394
 395         /*
 396          *      Add to the list only if it is EAP-Request, OR if
 397          *      it's LEAP, and a response.
 398          */
 399         if (((handler->eap_ds->request->code == PW_EAP_REQUEST) &&
 400             (handler->eap_ds->request->type.type >= PW_EAP_MD5)) ||
 401
 402                 /*
 403                  *      LEAP is a little different.  At Stage 4,
 404                  *      it sends an EAP-Success message, but we still
 405                  *      need to keep the State attribute & session
 406                  *      data structure around for the AP Challenge.
 407                  *
 408                  *      At stage 6, LEAP sends an EAP-Response, which
 409                  *      isn't put into the list.
 410                  */
 411             ((handler->eap_ds->response->code == PW_EAP_RESPONSE) &&
 412              (handler->eap_ds->response->type.type == PW_EAP_LEAP) &&
 413              (handler->eap_ds->request->code == PW_EAP_SUCCESS) &&
 414              (handler->eap_ds->request->type.type == 0))) {
 415
 416                 /*
 417                  *      Return FAIL if we can't remember the handler.
 418                  *      This is actually disallowed by the
 419                  *      specification, as unexpected FAILs could have
 420                  *      been forged.  However, we want to signal to
 421                  *      everyone else involved that we are
 422                  *      intentionally failing the session, as opposed
 423                  *      to accidentally failing it.
 424                  */
 425                 if (!eaplist_add(inst, handler)) {
 426                         eap_fail(handler);
 427                         eap_handler_free(inst, handler);
 428                         return RLM_MODULE_FAIL;
 429                 }
 430
 431         } else {
 432                 RDEBUG2("Freeing handler");
 433                 /* handler is not required any more, free it now */
 434                 eap_handler_free(inst, handler);
 435         }
 436
 437         /*
 438          *      If it's an Access-Accept, RFC 2869, Section 2.3.1
 439          *      says that we MUST include a User-Name attribute in the
 440          *      Access-Accept.
 441          */
 442         if ((request->reply->code == PW_AUTHENTICATION_ACK) &&
 443             request->username) {
 444                 VALUE_PAIR *vp;
 445
 446                 /*
 447                  *      Doesn't exist, add it in.
 448                  */
 449                 vp = pairfind(request->reply->vps, PW_USER_NAME, 0);
 450                 if (!vp) {
 451                         vp = pairmake("User-Name", "",
 452                                       T_OP_EQ);
 453                         strlcpy(vp->vp_strvalue, request->username->vp_strvalue,
 454                                 sizeof(vp->vp_strvalue));
 455                         vp->length = request->username->length;
 456                         rad_assert(vp != NULL);
 457                         pairadd(&(request->reply->vps), vp);
 458                 }
 459
 460                 /*
 461                  *      Cisco AP1230 has a bug and needs a zero
 462                  *      terminated string in Access-Accept.
 463                  */
 464                 if ((inst->cisco_accounting_username_bug) &&
 465                     (vp->length < (int) sizeof(vp->vp_strvalue))) {
 466                         vp->vp_strvalue[vp->length] = '\0';
 467                         vp->length++;
 468                 }
 469         }
 470
 471         return rcode;
 472 }
 473
 474 /*
 475  * EAP authorization DEPENDS on other rlm authorizations,
 476  * to check for user existance & get their configured values.
 477  * It Handles EAP-START Messages, User-Name initilization.
 478  */
 479 static int eap_authorize(void *instance, REQUEST *request)
 480 {
 481         rlm_eap_t       *inst;
 482         int             status;
 483         VALUE_PAIR      *vp;
 484
 485         inst = (rlm_eap_t *)instance;
 486
 487 #ifdef WITH_PROXY
 488         /*
 489          *      We don't do authorization again, once we've seen the
 490          *      proxy reply (or the proxied packet)
 491          */
 492         if (request->proxy != NULL)
 493                 return RLM_MODULE_NOOP;
 494 #endif
 495
 496         /*
 497          *      For EAP_START, send Access-Challenge with EAP Identity
 498          *      request.  even when we have to proxy this request
 499          *
 500          *      RFC 2869, Section 2.3.1 notes that the "domain" of the
 501          *      user, (i.e. where to proxy him) comes from the EAP-Identity,
 502          *      so we CANNOT proxy the user, until we know his identity.
 503          *
 504          *      We therefore send an EAP Identity request.
 505          */
 506         status = eap_start(inst, request);
 507         switch(status) {
 508         case EAP_NOOP:
 509                 return RLM_MODULE_NOOP;
 510         case EAP_FAIL:
 511                 return RLM_MODULE_FAIL;
 512         case EAP_FOUND:
 513                 return RLM_MODULE_HANDLED;
 514         case EAP_OK:
 515         case EAP_NOTFOUND:
 516         default:
 517                 break;
 518         }
 519
 520         /*
 521          *      RFC 2869, Section 2.3.1.  If a NAS sends an EAP-Identity,
 522          *      it MUST copy the identity into the User-Name attribute.
 523          *
 524          *      But we don't worry about that too much.  We depend on
 525          *      each EAP sub-module to look for handler->request->username,
 526          *      and to get excited if it doesn't appear.
 527          */
 528
 529         vp = pairfind(request->config_items, PW_AUTH_TYPE, 0);
 530         if ((!vp) ||
 531             (vp->vp_integer != PW_AUTHTYPE_REJECT)) {
 532                 vp = pairmake("Auth-Type", inst->xlat_name, T_OP_EQ);
 533                 if (!vp) {
 534                         RDEBUG2("Failed to create Auth-Type %s: %s\n",
 535                                 inst->xlat_name, fr_strerror());
 536                         return RLM_MODULE_FAIL;
 537                 }
 538                 pairadd(&request->config_items, vp);
 539         } else {
 540                 RDEBUG2("WARNING: Auth-Type already set.  Not setting to EAP");
 541         }
 542
 543         if (status == EAP_OK) return RLM_MODULE_OK;
 544
 545         return RLM_MODULE_UPDATED;
 546 }
 547
 548
 549 #ifdef WITH_PROXY
 550 /*
 551  *      If we're proxying EAP, then there may be magic we need
 552  *      to do.
 553  */
 554 static int eap_post_proxy(void *inst, REQUEST *request)
 555 {
 556         size_t          i;
 557         size_t          len;
 558         VALUE_PAIR      *vp;
 559         EAP_HANDLER     *handler;
 560
 561         /*
 562          *      Just in case the admin lists EAP in post-proxy-type Fail.
 563          */
 564         if (!request->proxy_reply) return RLM_MODULE_NOOP;
 565
 566         /*
 567          *      If there was a handler associated with this request,
 568          *      then it's a tunneled request which was proxied...
 569          */
 570         handler = request_data_get(request, inst, REQUEST_DATA_EAP_HANDLER);
 571         if (handler != NULL) {
 572                 int             rcode;
 573                 eap_tunnel_data_t *data;
 574
 575                 /*
 576                  *      Grab the tunnel callbacks from the request.
 577                  */
 578                 data = (eap_tunnel_data_t *) request_data_get(request,
 579                                                               request->proxy,
 580                                                               REQUEST_DATA_EAP_TUNNEL_CALLBACK);
 581                 if (!data) {
 582                         radlog_request(L_ERR, 0, request, "Failed to retrieve callback for tunneled session!");
 583                         eap_handler_free(inst, handler);
 584                         return RLM_MODULE_FAIL;
 585                 }
 586
 587                 /*
 588                  *      Do the callback...
 589                  */
 590                 RDEBUG2("Doing post-proxy callback");
 591                 rcode = data->callback(handler, data->tls_session);
 592                 free(data);
 593                 if (rcode == 0) {
 594                         RDEBUG2("Failed in post-proxy callback");
 595                         eap_fail(handler);
 596                         eap_handler_free(inst, handler);
 597                         return RLM_MODULE_REJECT;
 598                 }
 599
 600                 /*
 601                  *      We are done, wrap the EAP-request in RADIUS to send
 602                  *      with all other required radius attributes
 603                  */
 604                 eap_compose(handler);
 605
 606                 /*
 607                  *      Add to the list only if it is EAP-Request, OR if
 608                  *      it's LEAP, and a response.
 609                  */
 610                 if ((handler->eap_ds->request->code == PW_EAP_REQUEST) &&
 611                     (handler->eap_ds->request->type.type >= PW_EAP_MD5)) {
 612                         if (!eaplist_add(inst, handler)) {
 613                                 eap_fail(handler);
 614                                 eap_handler_free(inst, handler);
 615                                 return RLM_MODULE_FAIL;
 616                         }
 617
 618                 } else {        /* couldn't have been LEAP, there's no tunnel */
 619                         RDEBUG2("Freeing handler");
 620                         /* handler is not required any more, free it now */
 621                         eap_handler_free(inst, handler);
 622                 }
 623
 624                 /*
 625                  *      If it's an Access-Accept, RFC 2869, Section 2.3.1
 626                  *      says that we MUST include a User-Name attribute in the
 627                  *      Access-Accept.
 628                  */
 629                 if ((request->reply->code == PW_AUTHENTICATION_ACK) &&
 630                     request->username) {
 631                         /*
 632                          *      Doesn't exist, add it in.
 633                          */
 634                         vp = pairfind(request->reply->vps, PW_USER_NAME, 0);
 635                         if (!vp) {
 636                                 vp = pairmake("User-Name", request->username->vp_strvalue,
 637                                               T_OP_EQ);
 638                                 rad_assert(vp != NULL);
 639                                 pairadd(&(request->reply->vps), vp);
 640                         }
 641                 }
 642
 643                 return RLM_MODULE_OK;
 644         } else {
 645                 RDEBUG2("No pre-existing handler found");
 646         }
 647
 648         /*
 649          *      There may be more than one Cisco-AVPair.
 650          *      Ensure we find the one with the LEAP attribute.
 651          */
 652         vp = request->proxy_reply->vps;
 653         for (;;) {
 654                 /*
 655                  *      Hmm... there's got to be a better way to
 656                  *      discover codes for vendor attributes.
 657                  *
 658                  *      This is vendor Cisco (9), Cisco-AVPair
 659                  *      attribute (1)
 660                  */
 661                 vp = pairfind(vp, 1, 9);
 662                 if (!vp) {
 663                         return RLM_MODULE_NOOP;
 664                 }
 665
 666                 /*
 667                  *      If it's "leap:session-key", then stop.
 668                  *
 669                  *      The format is VERY specific!
 670                  */
 671                 if (strncasecmp(vp->vp_strvalue, "leap:session-key=", 17) == 0) {
 672                         break;
 673                 }
 674
 675                 /*
 676                  *      Not this AV-pair.  Go to the next one.
 677                  */
 678                 vp = vp->next;
 679         }
 680
 681         /*
 682          *      The format is very specific.
 683          */
 684         if (vp->length != 17 + 34) {
 685                 RDEBUG2("Cisco-AVPair with leap:session-key has incorrect length %d: Expected %d",
 686                        vp->length, 17 + 34);
 687                 return RLM_MODULE_NOOP;
 688         }
 689
 690         /*
 691          *      Decrypt the session key, using the proxy data.
 692          */
 693         i = 34;                 /* starts off with 34 octets */
 694         len = rad_tunnel_pwdecode(vp->vp_octets + 17, &i,
 695                                   request->home_server->secret,
 696                                   request->proxy->vector);
 697
 698         /*
 699          *      FIXME: Assert that i == 16.
 700          */
 701
 702         /*
 703          *      Encrypt the session key again, using the request data.
 704          */
 705         rad_tunnel_pwencode(vp->vp_strvalue + 17, &len,
 706                             request->client->secret,
 707                             request->packet->vector);
 708
 709         return RLM_MODULE_UPDATED;
 710 }
 711 #endif
 712
 713 /*
 714  *      The module name should be the only globally exported symbol.
 715  *      That is, everything else should be 'static'.
 716  */
 717 module_t rlm_eap = {
 718         RLM_MODULE_INIT,
 719         "eap",
 720         RLM_TYPE_CHECK_CONFIG_SAFE,     /* type */
 721         eap_instantiate,                /* instantiation */
 722         eap_detach,                     /* detach */
 723         {
 724                 eap_authenticate,       /* authentication */
 725                 eap_authorize,          /* authorization */
 726                 NULL,                   /* preaccounting */
 727                 NULL,                   /* accounting */
 728                 NULL,                   /* checksimul */
 729                 NULL,                   /* pre-proxy */
 730 #ifdef WITH_PROXY
 731                 eap_post_proxy,         /* post-proxy */
 732 #else
 733                 NULL,
 734 #endif
 735                 NULL                    /* post-auth */
 736         },
 737 };