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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  * Copyright 2000,2001  The FreeRADIUS server project
  21  * Copyright 2001  hereUare Communications, Inc. <raghud@hereuare.com>
  22  */
  23
  24 #include "autoconf.h"
  25 #include "eap.h"
  26
  27 static CONF_PARSER module_config[] = {
  28         { "default_eap_type", PW_TYPE_STRING_PTR, offsetof(EAP_CONF, default_eap_type), NULL, "md5" },
  29         { "timer_expire", PW_TYPE_INTEGER, offsetof(EAP_CONF, timer_limit), NULL, "60"},
  30
  31         { NULL, -1, 0, NULL, NULL }           /* end the list */
  32 };
  33
  34 static int eap_init(void)
  35 {
  36         return 0;
  37 }
  38
  39
  40 /*
  41  * read the config section and load all the eap authentication types present.
  42  */
  43 static int eap_instantiate(CONF_SECTION *cs, void **instance)
  44 {
  45         char            *auth_name;
  46         CONF_SECTION    *scs;
  47         EAP_TYPES       *types;
  48         EAP_CONF        *conf;
  49         rlm_eap_t       **eap_stuff;
  50
  51         eap_stuff = (rlm_eap_t **)instance;
  52         types    = NULL;
  53         conf     = NULL;
  54         auth_name = NULL;
  55
  56         conf = (EAP_CONF *)malloc(sizeof(EAP_CONF));
  57         if (conf == NULL) {
  58                 radlog(L_ERR, "rlm_eap: out of memory");
  59                 return -1;
  60         }
  61         if (cf_section_parse(cs, conf, module_config) < 0) {
  62                 free(conf);
  63                 return -1;
  64         }
  65
  66         for(scs=cf_subsection_find_next(cs, NULL, NULL);
  67                         scs != NULL;
  68                         scs=cf_subsection_find_next(cs, scs, NULL)) {
  69                 auth_name = cf_section_name1(scs);
  70
  71                 if (!auth_name)  continue;
  72                 eaptype_load(&types, auth_name, scs);
  73         }
  74
  75         if (!types) {
  76                 free(conf->default_eap_type);
  77                 conf->default_eap_type = NULL;
  78                 free(conf);
  79                 conf = NULL;
  80                 return -1;
  81         }
  82
  83         *eap_stuff = (rlm_eap_t *)malloc(sizeof(rlm_eap_t));
  84         if (*eap_stuff) {
  85                 (*eap_stuff)->typelist = types;
  86                 (*eap_stuff)->echolist = NULL;
  87                 (*eap_stuff)->conf = conf;
  88         }  else {
  89                 radlog(L_ERR, "rlm_eap: out of memory");
  90                 eaptype_freelist(&types);
  91                 return -1;
  92         }
  93
  94         /* Generate a state key, specific to eap */
  95         generate_key();
  96         return 0;
  97 }
  98
  99 /*
 100  * delete all the allocated space by eap module
 101  */
 102 static int eap_detach(void *instance)
 103 {
 104         rlm_eap_t *t;
 105         t = (rlm_eap_t *)instance;
 106
 107         eaplist_free(&(t->echolist));
 108         eaptype_freelist(&(t->typelist));
 109
 110         free(t->conf->default_eap_type);
 111         free(t->conf);
 112
 113         free(t);
 114
 115         return 0;
 116 }
 117
 118 /*
 119  * Assumption: Any one of the Authorization module should
 120  *      get the configured password for any valid user.
 121  *      If not, Authentication fails to validate.
 122  *
 123  * All EAP types will be handled in their respective sub modules.
 124  *
 125  * To Handle EAP-response, we keep track of the EAP-request we send.
 126  * When Success or Failure or when timed out, we delete them.
 127  */
 128 static int eap_authenticate(void *instance, REQUEST *request)
 129 {
 130         EAP_HANDLER     *handler;
 131         rlm_eap_t       *eap_stuff;
 132         eap_packet_t    *eap_packet;
 133         int             status;
 134
 135         eap_stuff = (rlm_eap_t *)instance;
 136
 137         /*
 138          * Always, clean the list first as it is not timer based
 139          * FIXME: Appropriate cleaning mechanism.
 140          */
 141         eaplist_clean(&(eap_stuff->echolist), (time_t)eap_stuff->conf->timer_limit);
 142
 143         /*
 144          * Incase if EAP is not configured in autz block
 145          * or eap_authorize is not invoked
 146          */
 147         status = eap_start(request);
 148         switch(status) {
 149         case EAP_NOOP:
 150                 return RLM_MODULE_NOOP;
 151         case EAP_FAIL:
 152                 return RLM_MODULE_FAIL;
 153         case EAP_FOUND:
 154                 return RLM_MODULE_OK;
 155         case EAP_NOTFOUND:
 156         default:
 157                 break;
 158         }
 159
 160         /* get the eap packet  to start with */
 161         eap_packet = eap_attribute(request->packet->vps);
 162         if (eap_packet == NULL) {
 163                 radlog(L_ERR, "rlm_eap: Malformed EAP Message");
 164                 return RLM_MODULE_FAIL;
 165         }
 166
 167         /*
 168          * create the eap handler
 169          */
 170         handler = eap_handler(&(eap_stuff->echolist), &eap_packet, request);
 171         if (handler == NULL) {
 172                 return RLM_MODULE_INVALID;
 173         }
 174
 175         /*
 176          * No User-Name, No authentication
 177          */
 178         if (request->username == NULL) {
 179                 radlog(L_ERR, "rlm_eap: Unknown User, authentication failed");
 180                 return RLM_MODULE_REJECT;
 181         }
 182
 183         /*
 184          * Always get the configured values, for each user.
 185          * to pass it to the specific EAP-Type
 186          */
 187         handler->configured = paircopy(request->config_items);
 188         if (handler->configured == NULL) {
 189                 radlog(L_INFO, "rlm_eap: No configured information for this user");
 190
 191                 /*
 192                  * FIXME: I think at least one item should be configured for any user
 193                  *      If nothing is configured, then atleast
 194                  *      config_items should provide the same username
 195                  *      if the user is present in the database
 196                  */
 197                 /*
 198                 eap_fail(request, handler->eap_ds->request);
 199                 eap_handler_free(&handler);
 200                 return RLM_MODULE_INVALID;
 201                 */
 202         }
 203
 204
 205         /*
 206          * Select the appropriate eap_type or default to the configured one
 207          */
 208         if (eaptype_select(eap_stuff->typelist, handler,
 209                 eap_stuff->conf->default_eap_type) == EAP_INVALID) {
 210
 211                 eap_fail(request, handler->eap_ds->request);
 212                 eap_handler_free(&handler);
 213                 return RLM_MODULE_INVALID;
 214         }
 215
 216         /*
 217          * We are done, wrap the EAP-request in RADIUS to send
 218          * with all other required radius attributes
 219          */
 220         eap_compose(request, handler->eap_ds->request);
 221
 222         /*
 223          * Add to the list only if it is EAP-Request
 224          */
 225         if ((handler->eap_ds->request->code == PW_EAP_REQUEST) &&
 226                 (handler->eap_ds->request->type.type >= PW_EAP_MD5)) {
 227
 228                 handler->id = eap_generateid(request, (u_char)handler->eap_ds->request->id);
 229                 if (handler->id == NULL) {
 230                         radlog(L_ERR, "rlm_eap: problem in generating ID, Present EAP is no more Valid");
 231                         eap_handler_free(&handler);
 232                 } else {
 233                         eaplist_add(&(eap_stuff->echolist), handler);
 234                 }
 235         } else {
 236                 /* handler is no more required, free it now */
 237                 eap_handler_free(&handler);
 238         }
 239         return RLM_MODULE_OK;
 240 }
 241
 242 /*
 243  * EAP authorization DEPENDS on other rlm authorizations,
 244  * to check for user existance & get their configured values.
 245  * It Handles EAP-START Messages, User-Name initilization.
 246  */
 247 static int eap_authorize(void *instance, REQUEST *request)
 248 {
 249         VALUE_PAIR      *atype, *vp;
 250         rlm_eap_t       *eap_stuff;
 251         eap_packet_t    *eap_packet;
 252         int             status;
 253         unsigned char   *id;
 254
 255         eap_stuff = (rlm_eap_t *)instance;
 256
 257         /* Authorization not valid for proxies */
 258         if (request->proxy != NULL)
 259                 return RLM_MODULE_NOOP;
 260
 261         /*
 262          * For EAP_START, send Access-Challenge with EAP Identity request.
 263          * even when we have to proxy this request
 264          */
 265         status = eap_start(request);
 266         switch(status) {
 267         case EAP_NOOP:
 268                 return RLM_MODULE_NOOP;
 269         case EAP_FAIL:
 270                 return RLM_MODULE_FAIL;
 271         case EAP_FOUND:
 272                 return RLM_MODULE_HANDLED;
 273         case EAP_NOTFOUND:
 274         default:
 275                 break;
 276         }
 277
 278         /*
 279          * We should have User-Name to proceed further
 280          */
 281         if (request->username == NULL) {
 282
 283                 /* get the eap packet */
 284                 eap_packet = eap_attribute(request->packet->vps);
 285                 if (eap_packet == NULL) {
 286                         radlog(L_ERR, "rlm_eap: Malformed EAP Message");
 287                         return RLM_MODULE_FAIL;
 288                 }
 289
 290                 id = eap_regenerateid(request, eap_packet->id);
 291                 if (id == NULL) {
 292                         radlog(L_ERR, "rlm_eap: User-Name cannot be obtained");
 293                         free(eap_packet);
 294                         return RLM_MODULE_FAIL;
 295                 }
 296
 297                 request->username = eap_useridentity(eap_stuff->echolist, eap_packet, id);
 298                 if (request->username == NULL) {
 299                         radlog(L_ERR, "rlm_eap: Unknown User, authorization failed");
 300                         free(eap_packet);
 301                         free(id);
 302                         return RLM_MODULE_FAIL;
 303                 }
 304                 free(eap_packet);
 305                 free(id);
 306         }
 307
 308         /*
 309          * Enforce EAP authentication
 310
 311          * Auth-type(s) already set?  overide it with EAP
 312          * If EAP-Message is present in RADIUS, then EAP authentication is MUST.
 313
 314          * TODO: When Multiple authentications are supported in RADIUS,
 315          *     then prioritize EAP by prepending it before all Auth-Types
 316          */
 317
 318         atype = pairfind(request->config_items, PW_AUTHTYPE);
 319         if ((atype == NULL) ||
 320                 ((atype->lvalue != PW_AUTHTYPE_EAP) &&
 321                 (atype->lvalue != PW_AUTHTYPE_ACCEPT) &&
 322                 (atype->lvalue != PW_AUTHTYPE_REJECT))) {
 323
 324                 vp = pairmake("Auth-Type", "EAP", T_OP_EQ);
 325                 if (vp == NULL) {
 326                         return RLM_MODULE_FAIL;
 327                 }
 328                 /* to overide */
 329                 pairdelete(&request->config_items, PW_AUTHTYPE);
 330                 pairadd(&request->config_items, vp);
 331
 332                 /* To prioritize
 333                 vp->next = request->config_items;
 334                 request->config_items = vp;
 335                 */
 336         }
 337
 338         return RLM_MODULE_UPDATED;
 339 }
 340
 341 /*
 342  *      The module name should be the only globally exported symbol.
 343  *      That is, everything else should be 'static'.
 344  */
 345 module_t rlm_eap = {
 346         "eap",
 347         RLM_TYPE_THREAD_UNSAFE,         /* type */
 348         eap_init,                       /* initialization */
 349         eap_instantiate,                /* instantiation */
 350         {
 351                 eap_authenticate,       /* authentication */
 352                 eap_authorize,          /* authorization */
 353                 NULL,                   /* preaccounting */
 354                 NULL,                   /* accounting */
 355                 NULL                    /* checksimul */
 356         },
 357         eap_detach,                     /* detach */
 358         NULL,                           /* destroy */
 359 };