src/modules/rlm_eap/types/rlm_eap_peap/rlm_eap_peap.c

   1 /*
   2  * rlm_eap_peap.c  contains the interfaces that are called from eap
   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 2003 Alan DeKok <aland@freeradius.org>
  21  * Copyright 2006 The FreeRADIUS server project
  22  */
  23
  24 #include <freeradius-devel/ident.h>
  25 RCSID("$Id$")
  26
  27 #include <freeradius-devel/autoconf.h>
  28 #include "eap_peap.h"
  29
  30 typedef struct rlm_eap_peap_t {
  31         /*
  32          *      Default tunneled EAP type
  33          */
  34         char    *default_eap_type_name;
  35         int     default_eap_type;
  36
  37         /*
  38          *      Use the reply attributes from the tunneled session in
  39          *      the non-tunneled reply to the client.
  40          */
  41         int     use_tunneled_reply;
  42
  43         /*
  44          *      Use SOME of the request attributes from outside of the
  45          *      tunneled session in the tunneled request
  46          */
  47         int     copy_request_to_tunnel;
  48
  49         /*
  50          *      Proxy tunneled session as EAP, or as de-capsulated
  51          *      protocol.
  52          */
  53         int     proxy_tunneled_request_as_eap;
  54
  55         /*
  56          *      Virtual server for inner tunnel session.
  57          */
  58         char    *virtual_server;
  59 } rlm_eap_peap_t;
  60
  61
  62 static CONF_PARSER module_config[] = {
  63         { "default_eap_type", PW_TYPE_STRING_PTR,
  64           offsetof(rlm_eap_peap_t, default_eap_type_name), NULL, "mschapv2" },
  65
  66         { "copy_request_to_tunnel", PW_TYPE_BOOLEAN,
  67           offsetof(rlm_eap_peap_t, copy_request_to_tunnel), NULL, "no" },
  68
  69         { "use_tunneled_reply", PW_TYPE_BOOLEAN,
  70           offsetof(rlm_eap_peap_t, use_tunneled_reply), NULL, "no" },
  71
  72         { "proxy_tunneled_request_as_eap", PW_TYPE_BOOLEAN,
  73           offsetof(rlm_eap_peap_t, proxy_tunneled_request_as_eap), NULL, "yes" },
  74
  75         { "virtual_server", PW_TYPE_STRING_PTR,
  76           offsetof(rlm_eap_peap_t, virtual_server), NULL, NULL },
  77
  78         { NULL, -1, 0, NULL, NULL }           /* end the list */
  79 };
  80
  81 /*
  82  *      Detach the module.
  83  */
  84 static int eappeap_detach(void *arg)
  85 {
  86         rlm_eap_peap_t *inst = (rlm_eap_peap_t *) arg;
  87
  88
  89         free(inst);
  90
  91         return 0;
  92 }
  93
  94 /*
  95  *      Attach the module.
  96  */
  97 static int eappeap_attach(CONF_SECTION *cs, void **instance)
  98 {
  99         rlm_eap_peap_t *inst;
 100
 101         inst = malloc(sizeof(*inst));
 102         if (!inst) {
 103                 radlog(L_ERR, "rlm_eap_peap: out of memory");
 104                 return -1;
 105         }
 106         memset(inst, 0, sizeof(*inst));
 107
 108         /*
 109          *      Parse the configuration attributes.
 110          */
 111         if (cf_section_parse(cs, inst, module_config) < 0) {
 112                 eappeap_detach(inst);
 113                 return -1;
 114         }
 115
 116         /*
 117          *      Convert the name to an integer, to make it easier to
 118          *      handle.
 119          */
 120         inst->default_eap_type = eaptype_name2type(inst->default_eap_type_name);
 121         if (inst->default_eap_type < 0) {
 122                 radlog(L_ERR, "rlm_eap_peap: Unknown EAP type %s",
 123                        inst->default_eap_type_name);
 124                 eappeap_detach(inst);
 125                 return -1;
 126         }
 127
 128         *instance = inst;
 129
 130         return 0;
 131 }
 132
 133 /*
 134  *      Free the PEAP per-session data
 135  */
 136 static void peap_free(void *p)
 137 {
 138         peap_tunnel_t *t = (peap_tunnel_t *) p;
 139
 140         if (!t) return;
 141
 142         pairfree(&t->username);
 143         pairfree(&t->state);
 144         pairfree(&t->accept_vps);
 145
 146         free(t);
 147 }
 148
 149
 150 /*
 151  *      Free the PEAP per-session data
 152  */
 153 static peap_tunnel_t *peap_alloc(rlm_eap_peap_t *inst)
 154 {
 155         peap_tunnel_t *t;
 156
 157         t = rad_malloc(sizeof(*t));
 158         memset(t, 0, sizeof(*t));
 159
 160         t->default_eap_type = inst->default_eap_type;
 161         t->copy_request_to_tunnel = inst->copy_request_to_tunnel;
 162         t->use_tunneled_reply = inst->use_tunneled_reply;
 163         t->proxy_tunneled_request_as_eap = inst->proxy_tunneled_request_as_eap;
 164         t->virtual_server = inst->virtual_server;
 165         t->session_resumption_state = PEAP_RESUMPTION_MAYBE;
 166
 167         return t;
 168 }
 169
 170 /*
 171  *      Do authentication, by letting EAP-TLS do most of the work.
 172  */
 173 static int eappeap_authenticate(void *arg, EAP_HANDLER *handler)
 174 {
 175         int rcode;
 176         eaptls_status_t status;
 177         rlm_eap_peap_t *inst = (rlm_eap_peap_t *) arg;
 178         tls_session_t *tls_session = (tls_session_t *) handler->opaque;
 179         peap_tunnel_t *peap = tls_session->opaque;
 180         REQUEST *request = handler->request;
 181
 182         /*
 183          *      Session resumption requires the storage of data, so
 184          *      allocate it if it doesn't already exist.
 185          */
 186         if (!tls_session->opaque) {
 187                 peap = tls_session->opaque = peap_alloc(inst);
 188                 tls_session->free_opaque = peap_free;
 189         }
 190
 191         status = eaptls_process(handler);
 192         RDEBUG2("eaptls_process returned %d\n", status);
 193         switch (status) {
 194                 /*
 195                  *      EAP-TLS handshake was successful, tell the
 196                  *      client to keep talking.
 197                  *
 198                  *      If this was EAP-TLS, we would just return
 199                  *      an EAP-TLS-Success packet here.
 200                  */
 201         case EAPTLS_SUCCESS:
 202                 if (SSL_session_reused(tls_session->ssl)) {
 203                         uint8_t tlv_packet[11];
 204
 205                         RDEBUG2("Skipping Phase2 because of session resumption.");
 206                         peap->session_resumption_state = PEAP_RESUMPTION_YES;
 207
 208                         tlv_packet[0] = PW_EAP_REQUEST;
 209                         tlv_packet[1] = handler->eap_ds->response->id +1;
 210                         tlv_packet[2] = 0;
 211                         tlv_packet[3] = 11;     /* length of this packet */
 212                         tlv_packet[4] = PW_EAP_TLV;
 213                         tlv_packet[5] = 0x80;
 214                         tlv_packet[6] = EAP_TLV_ACK_RESULT;
 215                         tlv_packet[7] = 0;
 216                         tlv_packet[8] = 2;      /* length of the data portion */
 217                         tlv_packet[9] = 0;
 218                         tlv_packet[10] = EAP_TLV_SUCCESS;
 219
 220                         peap->status = PEAP_STATUS_SENT_TLV_SUCCESS;
 221
 222                         (tls_session->record_plus)(&tls_session->clean_in, tlv_packet, 11);
 223                         tls_handshake_send(tls_session);
 224                         (tls_session->record_init)(&tls_session->clean_in);
 225
 226                 } else {
 227                         eap_packet_t eap_packet;
 228
 229                         eap_packet.code = PW_EAP_REQUEST;
 230                         eap_packet.id = handler->eap_ds->response->id + 1;
 231                         eap_packet.length[0] = 0;
 232                         eap_packet.length[1] = EAP_HEADER_LEN + 1;
 233                         eap_packet.data[0] = PW_EAP_IDENTITY;
 234
 235                         (tls_session->record_plus)(&tls_session->clean_in,
 236                                                   &eap_packet, sizeof(eap_packet));
 237
 238                         tls_handshake_send(tls_session);
 239                         (tls_session->record_init)(&tls_session->clean_in);
 240                 }
 241
 242                 eaptls_request(handler->eap_ds, tls_session);
 243                 RDEBUG2("EAPTLS_SUCCESS");
 244                 return 1;
 245
 246                 /*
 247                  *      The TLS code is still working on the TLS
 248                  *      exchange, and it's a valid TLS request.
 249                  *      do nothing.
 250                  */
 251         case EAPTLS_HANDLED:
 252           /*
 253            *    FIXME: If the SSL session is established, grab the state
 254            *    and EAP id from the inner tunnel, and update it with
 255            *    the expected EAP id!
 256            */
 257                 RDEBUG2("EAPTLS_HANDLED");
 258                 return 1;
 259
 260                 /*
 261                  *      Handshake is done, proceed with decoding tunneled
 262                  *      data.
 263                  */
 264         case EAPTLS_OK:
 265                 RDEBUG2("EAPTLS_OK");
 266                 break;
 267
 268                 /*
 269                  *      Anything else: fail.
 270                  */
 271         default:
 272                 RDEBUG2("EAPTLS_OTHERS");
 273                 return 0;
 274         }
 275
 276         /*
 277          *      Session is established, proceed with decoding
 278          *      tunneled data.
 279          */
 280         RDEBUG2("Session established.  Decoding tunneled attributes.");
 281
 282         /*
 283          *      We may need PEAP data associated with the session, so
 284          *      allocate it here, if it wasn't already alloacted.
 285          */
 286         if (!tls_session->opaque) {
 287                 tls_session->opaque = peap_alloc(inst);
 288                 tls_session->free_opaque = peap_free;
 289         }
 290
 291         /*
 292          *      Process the PEAP portion of the request.
 293          */
 294         rcode = eappeap_process(handler, tls_session);
 295         switch (rcode) {
 296         case RLM_MODULE_REJECT:
 297                 eaptls_fail(handler, 0);
 298                 return 0;
 299
 300         case RLM_MODULE_HANDLED:
 301                 eaptls_request(handler->eap_ds, tls_session);
 302                 return 1;
 303
 304         case RLM_MODULE_OK:
 305                 /*
 306                  *      Move the saved VP's from the Access-Accept to
 307                  *      our Access-Accept.
 308                  */
 309                 peap = tls_session->opaque;
 310                 if (peap->accept_vps) {
 311                         RDEBUG2("Using saved attributes from the original Access-Accept");
 312                         pairadd(&handler->request->reply->vps, &peap->accept_vps);
 313                         pairfree(&peap->accept_vps);
 314                 }
 315
 316                 /*
 317                  *      Success: Automatically return MPPE keys.
 318                  */
 319                 return eaptls_success(handler, 0);
 320
 321                 /*
 322                  *      No response packet, MUST be proxying it.
 323                  *      The main EAP module will take care of discovering
 324                  *      that the request now has a "proxy" packet, and
 325                  *      will proxy it, rather than returning an EAP packet.
 326                  */
 327         case RLM_MODULE_UPDATED:
 328                 rad_assert(handler->request->proxy != NULL);
 329                 return 1;
 330                 break;
 331
 332         default:
 333                 break;
 334         }
 335
 336         eaptls_fail(handler, 0);
 337         return 0;
 338 }
 339
 340
 341 /*
 342  *      The module name should be the only globally exported symbol.
 343  *      That is, everything else should be 'static'.
 344  */
 345 EAP_TYPE rlm_eap_peap = {
 346         "eap_peap",
 347         eappeap_attach,                 /* attach */
 348         /*
 349          *      Note! There is NO eappeap_initate() function, as the
 350          *      main EAP module takes care of calling
 351          *      eaptls_initiate().
 352          *
 353          *      This is because PEAP is a protocol on top of TLS, so
 354          *      before we need to do PEAP, we've got to initiate a TLS
 355          *      session.
 356          */
 357         NULL,                           /* Start the initial request */
 358         NULL,                           /* authorization */
 359         eappeap_authenticate,           /* authentication */
 360         eappeap_detach                  /* detach */
 361 };