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 } rlm_eap_peap_t;
  55
  56
  57 static CONF_PARSER module_config[] = {
  58         { "default_eap_type", PW_TYPE_STRING_PTR,
  59           offsetof(rlm_eap_peap_t, default_eap_type_name), NULL, "mschapv2" },
  60
  61         { "copy_request_to_tunnel", PW_TYPE_BOOLEAN,
  62           offsetof(rlm_eap_peap_t, copy_request_to_tunnel), NULL, "no" },
  63
  64         { "use_tunneled_reply", PW_TYPE_BOOLEAN,
  65           offsetof(rlm_eap_peap_t, use_tunneled_reply), NULL, "no" },
  66
  67         { "proxy_tunneled_request_as_eap", PW_TYPE_BOOLEAN,
  68           offsetof(rlm_eap_peap_t, proxy_tunneled_request_as_eap), NULL, "yes" },
  69
  70         { NULL, -1, 0, NULL, NULL }           /* end the list */
  71 };
  72
  73 /*
  74  *      Detach the module.
  75  */
  76 static int eappeap_detach(void *arg)
  77 {
  78         rlm_eap_peap_t *inst = (rlm_eap_peap_t *) arg;
  79
  80
  81         free(inst);
  82
  83         return 0;
  84 }
  85
  86 /*
  87  *      Attach the module.
  88  */
  89 static int eappeap_attach(CONF_SECTION *cs, void **instance)
  90 {
  91         rlm_eap_peap_t *inst;
  92
  93         inst = malloc(sizeof(*inst));
  94         if (!inst) {
  95                 radlog(L_ERR, "rlm_eap_peap: out of memory");
  96                 return -1;
  97         }
  98         memset(inst, 0, sizeof(*inst));
  99
 100         /*
 101          *      Parse the configuration attributes.
 102          */
 103         if (cf_section_parse(cs, inst, module_config) < 0) {
 104                 eappeap_detach(inst);
 105                 return -1;
 106         }
 107
 108         /*
 109          *      Convert the name to an integer, to make it easier to
 110          *      handle.
 111          */
 112         inst->default_eap_type = eaptype_name2type(inst->default_eap_type_name);
 113         if (inst->default_eap_type < 0) {
 114                 radlog(L_ERR, "rlm_eap_peap: Unknown EAP type %s",
 115                        inst->default_eap_type_name);
 116                 eappeap_detach(inst);
 117                 return -1;
 118         }
 119
 120         *instance = inst;
 121
 122         return 0;
 123 }
 124
 125 /*
 126  *      Free the PEAP per-session data
 127  */
 128 static void peap_free(void *p)
 129 {
 130         peap_tunnel_t *t = (peap_tunnel_t *) p;
 131
 132         if (!t) return;
 133
 134         pairfree(&t->username);
 135         pairfree(&t->state);
 136         pairfree(&t->accept_vps);
 137
 138         free(t);
 139 }
 140
 141
 142 /*
 143  *      Free the PEAP per-session data
 144  */
 145 static peap_tunnel_t *peap_alloc(rlm_eap_peap_t *inst)
 146 {
 147         peap_tunnel_t *t;
 148
 149         t = rad_malloc(sizeof(*t));
 150         memset(t, 0, sizeof(*t));
 151
 152         t->default_eap_type = inst->default_eap_type;
 153         t->copy_request_to_tunnel = inst->copy_request_to_tunnel;
 154         t->use_tunneled_reply = inst->use_tunneled_reply;
 155         t->proxy_tunneled_request_as_eap = inst->proxy_tunneled_request_as_eap;
 156
 157         return t;
 158 }
 159
 160 /*
 161  *      Do authentication, by letting EAP-TLS do most of the work.
 162  */
 163 static int eappeap_authenticate(void *arg, EAP_HANDLER *handler)
 164 {
 165         int rcode;
 166         eaptls_status_t status;
 167         rlm_eap_peap_t *inst = (rlm_eap_peap_t *) arg;
 168         tls_session_t *tls_session = (tls_session_t *) handler->opaque;
 169
 170         DEBUG2("  rlm_eap_peap: Authenticate");
 171
 172         status = eaptls_process(handler);
 173         DEBUG2("  eaptls_process returned %d\n", status);
 174         switch (status) {
 175                 /*
 176                  *      EAP-TLS handshake was successful, tell the
 177                  *      client to keep talking.
 178                  *
 179                  *      If this was EAP-TLS, we would just return
 180                  *      an EAP-TLS-Success packet here.
 181                  */
 182         case EAPTLS_SUCCESS:
 183                 {
 184                         eap_packet_t eap_packet;
 185
 186                         eap_packet.code = PW_EAP_REQUEST;
 187                         eap_packet.id = handler->eap_ds->response->id + 1;
 188                         eap_packet.length[0] = 0;
 189                         eap_packet.length[1] = EAP_HEADER_LEN + 1;
 190                         eap_packet.data[0] = PW_EAP_IDENTITY;
 191
 192                         (tls_session->record_plus)(&tls_session->clean_in,
 193                                                   &eap_packet, sizeof(eap_packet));
 194
 195                         tls_handshake_send(tls_session);
 196                         (tls_session->record_init)(&tls_session->clean_in);
 197                 }
 198                 eaptls_request(handler->eap_ds, tls_session);
 199                 DEBUG2("  rlm_eap_peap: EAPTLS_SUCCESS");
 200                 return 1;
 201
 202                 /*
 203                  *      The TLS code is still working on the TLS
 204                  *      exchange, and it's a valid TLS request.
 205                  *      do nothing.
 206                  */
 207         case EAPTLS_HANDLED:
 208                 DEBUG2("  rlm_eap_peap: EAPTLS_HANDLED");
 209                 return 1;
 210
 211                 /*
 212                  *      Handshake is done, proceed with decoding tunneled
 213                  *      data.
 214                  */
 215         case EAPTLS_OK:
 216                 DEBUG2("  rlm_eap_peap: EAPTLS_OK");
 217                 break;
 218
 219                 /*
 220                  *      Anything else: fail.
 221                  */
 222         default:
 223                 DEBUG2("  rlm_eap_peap: EAPTLS_OTHERS");
 224                 return 0;
 225         }
 226
 227         /*
 228          *      Session is established, proceed with decoding
 229          *      tunneled data.
 230          */
 231         DEBUG2("  rlm_eap_peap: Session established.  Decoding tunneled attributes.");
 232
 233         /*
 234          *      We may need PEAP data associated with the session, so
 235          *      allocate it here, if it wasn't already alloacted.
 236          */
 237         if (!tls_session->opaque) {
 238                 tls_session->opaque = peap_alloc(inst);
 239                 tls_session->free_opaque = peap_free;
 240         }
 241
 242         /*
 243          *      Process the PEAP portion of the request.
 244          */
 245         rcode = eappeap_process(handler, tls_session);
 246         switch (rcode) {
 247         case RLM_MODULE_REJECT:
 248                 eaptls_fail(handler->eap_ds, 0);
 249                 return 0;
 250
 251         case RLM_MODULE_HANDLED:
 252                 eaptls_request(handler->eap_ds, tls_session);
 253                 return 1;
 254
 255         case RLM_MODULE_OK:
 256                 eaptls_success(handler->eap_ds, 0);
 257
 258                 /*
 259                  *      Move the saved VP's from the Access-Accept to
 260                  *      our Access-Accept.
 261                  */
 262                 if (((peap_tunnel_t *) tls_session->opaque)->accept_vps) {
 263                         DEBUG2("  Using saved attributes from the original Access-Accept");
 264                 }
 265                 pairadd(&handler->request->reply->vps,
 266                         ((peap_tunnel_t *) tls_session->opaque)->accept_vps);
 267                 ((peap_tunnel_t *) tls_session->opaque)->accept_vps = NULL;
 268
 269                 eaptls_gen_mppe_keys(&handler->request->reply->vps,
 270                                      tls_session->ssl,
 271                                      "client EAP encryption");
 272
 273                 return 1;
 274
 275                 /*
 276                  *      No response packet, MUST be proxying it.
 277                  *      The main EAP module will take care of discovering
 278                  *      that the request now has a "proxy" packet, and
 279                  *      will proxy it, rather than returning an EAP packet.
 280                  */
 281         case RLM_MODULE_UPDATED:
 282                 rad_assert(handler->request->proxy != NULL);
 283                 return 1;
 284                 break;
 285
 286         default:
 287                 break;
 288         }
 289
 290         eaptls_fail(handler->eap_ds, 0);
 291         return 0;
 292 }
 293
 294
 295 /*
 296  *      The module name should be the only globally exported symbol.
 297  *      That is, everything else should be 'static'.
 298  */
 299 EAP_TYPE rlm_eap_peap = {
 300         "eap_peap",
 301         eappeap_attach,                 /* attach */
 302         /*
 303          *      Note! There is NO eappeap_initate() function, as the
 304          *      main EAP module takes care of calling
 305          *      eaptls_initiate().
 306          *
 307          *      This is because PEAP is a protocol on top of TLS, so
 308          *      before we need to do PEAP, we've got to initiate a TLS
 309          *      session.
 310          */
 311         NULL,                           /* Start the initial request */
 312         NULL,                           /* authorization */
 313         eappeap_authenticate,           /* authentication */
 314         eappeap_detach                  /* detach */
 315 };