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