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

   1 /*
   2  * 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 RCSID("$Id$")
  25 USES_APPLE_DEPRECATED_API       /* OpenSSL API has been deprecated by Apple */
  26
  27 #include "eap_peap.h"
  28
  29 static int setup_fake_request(REQUEST *request, REQUEST *fake, peap_tunnel_t *t);
  30
  31 /*
  32  *      Send protected EAP-Failure
  33  *
  34  *       Result-TLV = Failure
  35  */
  36 static int eappeap_failure(eap_handler_t *handler, tls_session_t *tls_session)
  37 {
  38         uint8_t tlv_packet[11];
  39         REQUEST *request = handler->request;
  40
  41         RDEBUG2("FAILURE");
  42
  43         tlv_packet[0] = PW_EAP_REQUEST;
  44         tlv_packet[1] = handler->eap_ds->response->id +1;
  45         tlv_packet[2] = 0;
  46         tlv_packet[3] = 11;     /* length of this packet */
  47         tlv_packet[4] = PW_EAP_TLV;
  48         tlv_packet[5] = 0x80;
  49         tlv_packet[6] = EAP_TLV_ACK_RESULT;
  50         tlv_packet[7] = 0;
  51         tlv_packet[8] = 2;      /* length of the data portion */
  52         tlv_packet[9] = 0;
  53         tlv_packet[10] = EAP_TLV_FAILURE;
  54
  55         (tls_session->record_plus)(&tls_session->clean_in, tlv_packet, 11);
  56
  57         /*
  58          *      FIXME: Check the return code.
  59          */
  60         tls_handshake_send(request, tls_session);
  61
  62         return 1;
  63 }
  64
  65
  66 /*
  67  *      Send protected EAP-Success
  68  *
  69  *       Result-TLV = Success
  70  */
  71 static int eappeap_success(eap_handler_t *handler, tls_session_t *tls_session)
  72 {
  73         uint8_t tlv_packet[11];
  74         REQUEST *request = handler->request;
  75
  76         RDEBUG2("SUCCESS");
  77
  78         tlv_packet[0] = PW_EAP_REQUEST;
  79         tlv_packet[1] = handler->eap_ds->response->id +1;
  80         tlv_packet[2] = 0;
  81         tlv_packet[3] = 11;     /* length of this packet */
  82         tlv_packet[4] = PW_EAP_TLV;
  83         tlv_packet[5] = 0x80;   /* mandatory AVP */
  84         tlv_packet[6] = EAP_TLV_ACK_RESULT;
  85         tlv_packet[7] = 0;
  86         tlv_packet[8] = 2;      /* length of the data portion */
  87         tlv_packet[9] = 0;
  88         tlv_packet[10] = EAP_TLV_SUCCESS;
  89
  90         (tls_session->record_plus)(&tls_session->clean_in, tlv_packet, 11);
  91
  92         /*
  93          *      FIXME: Check the return code.
  94          */
  95         tls_handshake_send(request, tls_session);
  96
  97         return 1;
  98 }
  99
 100
 101 static int eappeap_identity(eap_handler_t *handler, tls_session_t *tls_session)
 102 {
 103         eap_packet_raw_t eap_packet;
 104
 105         eap_packet.code = PW_EAP_REQUEST;
 106         eap_packet.id = handler->eap_ds->response->id + 1;
 107         eap_packet.length[0] = 0;
 108         eap_packet.length[1] = EAP_HEADER_LEN + 1;
 109         eap_packet.data[0] = PW_EAP_IDENTITY;
 110
 111         (tls_session->record_plus)(&tls_session->clean_in,
 112                                   &eap_packet, sizeof(eap_packet));
 113
 114         tls_handshake_send(handler->request, tls_session);
 115         (tls_session->record_init)(&tls_session->clean_in);
 116
 117         return 1;
 118 }
 119
 120 /*
 121  * Send an MS SoH request
 122  */
 123 static int eappeap_soh(eap_handler_t *handler, tls_session_t *tls_session)
 124 {
 125         uint8_t tlv_packet[20];
 126
 127         tlv_packet[0] = 254;    /* extended type */
 128
 129         tlv_packet[1] = 0;
 130         tlv_packet[2] = 0x01;   /* ms vendor */
 131         tlv_packet[3] = 0x37;
 132
 133         tlv_packet[4] = 0;      /* ms soh eap */
 134         tlv_packet[5] = 0;
 135         tlv_packet[6] = 0;
 136         tlv_packet[7] = 0x21;
 137
 138         tlv_packet[8] = 0;      /* vendor-spec tlv */
 139         tlv_packet[9] = 7;
 140
 141         tlv_packet[10] = 0;
 142         tlv_packet[11] = 8;     /* payload len */
 143
 144         tlv_packet[12] = 0;     /* ms vendor */
 145         tlv_packet[13] = 0;
 146         tlv_packet[14] = 0x01;
 147         tlv_packet[15] = 0x37;
 148
 149         tlv_packet[16] = 0;
 150         tlv_packet[17] = 2;
 151         tlv_packet[18] = 0;
 152         tlv_packet[19] = 0;
 153
 154         (tls_session->record_plus)(&tls_session->clean_in, tlv_packet, 20);
 155         tls_handshake_send(handler->request, tls_session);
 156         return 1;
 157 }
 158
 159 static void eapsoh_verify(REQUEST *request, RADIUS_PACKET *packet,
 160                           uint8_t const *data, unsigned int data_len) {
 161
 162         VALUE_PAIR *vp;
 163         uint8_t eap_method_base;
 164         uint32_t eap_vendor;
 165         uint32_t eap_method;
 166         int rv;
 167
 168         vp = pairmake(packet, &packet->vps, "SoH-Supported", "no", T_OP_EQ);
 169         if (data && data[0] == PW_EAP_NAK) {
 170                 RDEBUG("SoH - client NAKed");
 171                 return;
 172         }
 173
 174         if (!data || data_len < 8) {
 175                 RDEBUG("SoH - eap payload too short");
 176                 return;
 177         }
 178
 179         eap_method_base = *data++;
 180         if (eap_method_base != 254) {
 181                 RDEBUG("SoH - response is not extended EAP: %i", eap_method_base);
 182                 return;
 183         }
 184
 185         eap_vendor = soh_pull_be_24(data); data += 3;
 186         if (eap_vendor != 0x137) {
 187                 RDEBUG("SoH - extended eap vendor %08x is not Microsoft", eap_vendor);
 188                 return;
 189         }
 190
 191         eap_method = soh_pull_be_32(data); data += 4;
 192         if (eap_method != 0x21) {
 193                 RDEBUG("SoH - response eap type %08x is not EAP-SoH", eap_method);
 194                 return;
 195         }
 196
 197
 198         rv = soh_verify(request, data, data_len - 8);
 199         if (rv<0) {
 200                 RDEBUG("SoH - error decoding payload: %s", fr_strerror());
 201         } else {
 202                 vp->vp_integer = 1;
 203         }
 204 }
 205
 206 /*
 207  *      Verify the tunneled EAP message.
 208  */
 209 static int eapmessage_verify(REQUEST *request,
 210                              uint8_t const *data, unsigned int data_len)
 211 {
 212         eap_packet_raw_t const *eap_packet = (eap_packet_raw_t const *) data;
 213         eap_type_t eap_method;
 214
 215         /*
 216          *      No data, OR only 1 byte of EAP type.
 217          */
 218         if (!data || (data_len == 0) ||
 219             ((data_len <= 1) && (data[0] != PW_EAP_IDENTITY))) {
 220                 return 0;
 221         }
 222
 223         eap_method = *data;
 224         switch (eap_method) {
 225         case PW_EAP_IDENTITY:
 226                 if (data_len == 1) {
 227                         RDEBUG2("Identity - ");
 228                         return 1;
 229                 }
 230                 RDEBUG2("Identity - %*s",
 231                        data_len - 1, data + 1);
 232                 return 1;
 233                 break;
 234
 235                 /*
 236                  *      If the first byte of the packet is
 237                  *      EAP-Response, and the EAP data is a TLV,
 238                  *      then it looks OK...
 239                  */
 240         case PW_EAP_RESPONSE:
 241                 if (eap_packet->data[0] == PW_EAP_TLV) {
 242                         RDEBUG2("Received EAP-TLV response.");
 243                         return 1;
 244                 }
 245                 RDEBUG2("Got something weird.");
 246                 break;
 247
 248
 249                 /*
 250                  *      We normally do Microsoft MS-CHAPv2 (26), versus
 251                  *      Cisco MS-CHAPv2 (29).
 252                  */
 253         case PW_EAP_MSCHAPV2:
 254         default:
 255                 RDEBUG2("EAP type %s (%d)", eap_type2name(eap_method),
 256                         eap_method);
 257                 return 1;
 258                 break;
 259         }
 260
 261         return 0;
 262 }
 263
 264 /*
 265  *      Convert a pseudo-EAP packet to a list of VALUE_PAIR's.
 266  */
 267 static VALUE_PAIR *eap2vp(REQUEST *request, RADIUS_PACKET *packet,
 268                           EAP_DS *eap_ds,
 269                           uint8_t const *data, size_t data_len)
 270 {
 271         size_t total;
 272         uint8_t *p;
 273         VALUE_PAIR *vp = NULL, *head = NULL;
 274         vp_cursor_t cursor;
 275
 276         if (data_len > 65535) return NULL; /* paranoia */
 277
 278         vp = paircreate(packet, PW_EAP_MESSAGE, 0);
 279         if (!vp) {
 280                 RDEBUG2("Failure in creating VP");
 281                 return NULL;
 282         }
 283
 284         total = data_len;
 285         if (total > 249) total = 249;
 286
 287         /*
 288          *      Hand-build an EAP packet from the crap in PEAP version 0.
 289          */
 290         vp->length = EAP_HEADER_LEN + total;
 291         vp->vp_octets = p = talloc_array(vp, uint8_t, vp->length);
 292
 293         p[0] = PW_EAP_RESPONSE;
 294         p[1] = eap_ds->response->id;
 295         p[2] = (data_len + EAP_HEADER_LEN) >> 8;
 296         p[3] = (data_len + EAP_HEADER_LEN) & 0xff;
 297
 298         memcpy(p + EAP_HEADER_LEN, data, total);
 299
 300         fr_cursor_init(&cursor, &head);
 301         fr_cursor_insert(&cursor, vp);
 302         while (total < data_len) {
 303                 vp = paircreate(packet, PW_EAP_MESSAGE, 0);
 304                 if (!vp) {
 305                         RDEBUG2("Failure in creating VP");
 306                         pairfree(&head);
 307                         return NULL;
 308                 }
 309
 310                 pairmemcpy(vp, data + total, (data_len - total));
 311
 312                 total += vp->length;
 313
 314                 fr_cursor_insert(&cursor, vp);
 315         }
 316
 317         return head;
 318 }
 319
 320
 321 /*
 322  *      Convert a list of VALUE_PAIR's to an EAP packet, through the
 323  *      simple expedient of dumping the EAP message
 324  */
 325 static int vp2eap(REQUEST *request, tls_session_t *tls_session, VALUE_PAIR *vp)
 326 {
 327         rad_assert(vp != NULL);
 328         VALUE_PAIR *this;
 329         vp_cursor_t cursor;
 330
 331         /*
 332          *      Skip the id, code, and length.  Just write the EAP
 333          *      type & data to the client.
 334          */
 335 #ifndef NDEBUG
 336         if ((debug_flag > 2) && fr_log_fp) {
 337                 size_t i, total, start = EAP_HEADER_LEN;
 338                 total = 0;
 339
 340                 for (this = fr_cursor_init(&cursor, &vp); this; this = fr_cursor_next(&cursor)) {
 341                         for (i = start; i < vp->length; i++) {
 342                                 if ((total & 0x0f) == 0) {
 343                                         fprintf(fr_log_fp, "  PEAP tunnel data out %04x: ", (int) total);
 344                                 }
 345                                 fprintf(fr_log_fp, "%02x ", vp->vp_octets[i]);
 346
 347                                 if ((total & 0x0f) == 0x0f) {
 348                                         fprintf(fr_log_fp, "\n");
 349                                 }
 350
 351                                 total++;
 352                         }
 353
 354                         start = 0;
 355                 }
 356
 357                 if ((total & 0x0f) != 0) {
 358                         fprintf(fr_log_fp, "\n");
 359                 }
 360         }
 361 #endif
 362
 363         /*
 364          *      Send the EAP data, WITHOUT the header.
 365          */
 366         (tls_session->record_plus)(&tls_session->clean_in, vp->vp_octets + EAP_HEADER_LEN, vp->length - EAP_HEADER_LEN);
 367
 368         /*
 369          *      Send the rest of the EAP data.
 370          */
 371         for (this = fr_cursor_init(&cursor, &vp);
 372              this;
 373              this = fr_cursor_next(&cursor)) {
 374                 (tls_session->record_plus)(&tls_session->clean_in, this->vp_octets, this->length);
 375         }
 376
 377         tls_handshake_send(request, tls_session);
 378
 379         return 1;
 380 }
 381
 382
 383 /*
 384  *      See if there's a TLV in the response.
 385  */
 386 static int eappeap_check_tlv(REQUEST *request, uint8_t const *data,
 387                              size_t data_len)
 388 {
 389         eap_packet_raw_t const *eap_packet = (eap_packet_raw_t const *) data;
 390
 391         if (data_len < 11) return 0;
 392
 393         /*
 394          *      Look for success or failure.
 395          */
 396         if ((eap_packet->code == PW_EAP_RESPONSE) &&
 397             (eap_packet->data[0] == PW_EAP_TLV)) {
 398                 if (data[10] == EAP_TLV_SUCCESS) {
 399                         return 1;
 400                 }
 401
 402                 if (data[10] == EAP_TLV_FAILURE) {
 403                         RDEBUG2("Client rejected our response.  The password is probably incorrect.");
 404                         return 0;
 405                 }
 406         }
 407
 408         RDEBUG("Unknown TLV %02x", data[10]);
 409
 410         return 0;
 411 }
 412
 413
 414 /*
 415  *      Use a reply packet to determine what to do.
 416  */
 417 static int process_reply(eap_handler_t *handler, tls_session_t *tls_session,
 418                          REQUEST *request, RADIUS_PACKET *reply)
 419 {
 420         int rcode = RLM_MODULE_REJECT;
 421         VALUE_PAIR *vp;
 422         peap_tunnel_t *t = tls_session->opaque;
 423
 424         if ((debug_flag > 0) && fr_log_fp) {
 425                 RDEBUG("Got tunneled reply RADIUS code %d",
 426                        reply->code);
 427
 428                 debug_pair_list(reply->vps);
 429         }
 430
 431         switch (reply->code) {
 432         case PW_AUTHENTICATION_ACK:
 433                 RDEBUG2("Tunneled authentication was successful.");
 434                 t->status = PEAP_STATUS_SENT_TLV_SUCCESS;
 435                 eappeap_success(handler, tls_session);
 436                 rcode = RLM_MODULE_HANDLED;
 437
 438                 /*
 439                  *      If we've been told to use the attributes from
 440                  *      the reply, then do so.
 441                  *
 442                  *      WARNING: This may leak information about the
 443                  *      tunneled user!
 444                  */
 445                 if (t->use_tunneled_reply) {
 446                         RDEBUG2("Saving tunneled attributes for later");
 447
 448                         /*
 449                          *      Clean up the tunneled reply.
 450                          */
 451                         pairdelete(&reply->vps, PW_PROXY_STATE, 0, TAG_ANY);
 452                         pairdelete(&reply->vps, PW_EAP_MESSAGE, 0, TAG_ANY);
 453                         pairdelete(&reply->vps, PW_MESSAGE_AUTHENTICATOR, 0, TAG_ANY);
 454
 455                         /*
 456                          *      Delete MPPE keys & encryption policy.  We don't
 457                          *      want these here.
 458                          */
 459                         pairdelete(&reply->vps, 7, VENDORPEC_MICROSOFT, TAG_ANY);
 460                         pairdelete(&reply->vps, 8, VENDORPEC_MICROSOFT, TAG_ANY);
 461                         pairdelete(&reply->vps, 16, VENDORPEC_MICROSOFT, TAG_ANY);
 462                         pairdelete(&reply->vps, 17, VENDORPEC_MICROSOFT, TAG_ANY);
 463
 464                         rad_assert(!t->accept_vps);
 465                         pairfilter(t, &t->accept_vps, &reply->vps, 0, 0, TAG_ANY);
 466                         rad_assert(!reply->vps);
 467                 }
 468                 break;
 469
 470         case PW_AUTHENTICATION_REJECT:
 471                 RDEBUG2("Tunneled authentication was rejected.");
 472                 t->status = PEAP_STATUS_SENT_TLV_FAILURE;
 473                 eappeap_failure(handler, tls_session);
 474                 rcode = RLM_MODULE_HANDLED;
 475                 break;
 476
 477         case PW_ACCESS_CHALLENGE:
 478                 RDEBUG2("Got tunneled Access-Challenge");
 479
 480                 /*
 481                  *      Keep the State attribute, if necessary.
 482                  *
 483                  *      Get rid of the old State, too.
 484                  */
 485                 pairfree(&t->state);
 486                 pairfilter(t, &t->state, &(reply->vps), PW_STATE, 0, TAG_ANY);
 487
 488                 /*
 489                  *      PEAP takes only EAP-Message attributes inside
 490                  *      of the tunnel.  Any Reply-Message in the
 491                  *      Access-Challenge is ignored.
 492                  */
 493                 vp = NULL;
 494                 pairfilter(t, &vp, &(reply->vps), PW_EAP_MESSAGE, 0, TAG_ANY);
 495
 496                 /*
 497                  *      Handle EAP-MSCHAP-V2, where Access-Accept's
 498                  *      from the home server may contain MS-CHAP-Success,
 499                  *      which the module turns into challenges, so that
 500                  *      the client may respond to the challenge with
 501                  *      an "ack" packet.
 502                  */
 503                 if (t->home_access_accept && t->use_tunneled_reply) {
 504                         RDEBUG2("Saving tunneled attributes for later");
 505
 506                         /*
 507                          *      Clean up the tunneled reply.
 508                          */
 509                         pairdelete(&reply->vps, PW_PROXY_STATE, 0, TAG_ANY);
 510                         pairdelete(&reply->vps, PW_MESSAGE_AUTHENTICATOR, 0, TAG_ANY);
 511
 512                         rad_assert(!t->accept_vps);
 513                         pairfilter(t, &t->accept_vps, &reply->vps,
 514                                   0, 0, TAG_ANY);
 515                         rad_assert(!reply->vps);
 516                 }
 517
 518                 /*
 519                  *      Handle the ACK, by tunneling any necessary reply
 520                  *      VP's back to the client.
 521                  */
 522                 if (vp) {
 523                         vp2eap(request, tls_session, vp);
 524                         pairfree(&vp);
 525                 }
 526
 527                 rcode = RLM_MODULE_HANDLED;
 528                 break;
 529
 530         default:
 531                 RDEBUG2("Unknown RADIUS packet type %d: rejecting tunneled user", reply->code);
 532                 rcode = RLM_MODULE_REJECT;
 533                 break;
 534         }
 535
 536         return rcode;
 537 }
 538
 539 #ifdef WITH_PROXY
 540 /*
 541  *      Do post-proxy processing,
 542  */
 543 static int eappeap_postproxy(eap_handler_t *handler, void *data)
 544 {
 545         int rcode;
 546         tls_session_t *tls_session = (tls_session_t *) data;
 547         REQUEST *fake, *request = handler->request;
 548
 549         rad_assert(request != NULL);
 550         RDEBUG2("Passing reply from proxy back into the tunnel.");
 551
 552         /*
 553          *      If there was a fake request associated with the proxied
 554          *      request, do more processing of it.
 555          */
 556         fake = (REQUEST *) request_data_get(handler->request,
 557                                             handler->request->proxy,
 558                                             REQUEST_DATA_EAP_MSCHAP_TUNNEL_CALLBACK);
 559
 560         /*
 561          *      Do the callback, if it exists, and if it was a success.
 562          */
 563         if (fake && (handler->request->proxy_reply->code == PW_AUTHENTICATION_ACK)) {
 564                 peap_tunnel_t *t = tls_session->opaque;
 565
 566                 t->home_access_accept = true;
 567
 568                 /*
 569                  *      Terrible hacks.
 570                  */
 571                 rad_assert(!fake->packet);
 572                 fake->packet = request->proxy;
 573                 fake->packet->src_ipaddr = request->packet->src_ipaddr;
 574                 request->proxy = NULL;
 575
 576                 rad_assert(!fake->reply);
 577                 fake->reply = request->proxy_reply;
 578                 request->proxy_reply = NULL;
 579
 580                 if ((debug_flag > 0) && fr_log_fp) {
 581                         fprintf(fr_log_fp, "server %s {\n", fake->server);
 582                 }
 583
 584                 /*
 585                  *      Perform a post-auth stage, which will get the EAP
 586                  *      handler, too...
 587                  */
 588                 fake->options &= ~RAD_REQUEST_OPTION_PROXY_EAP;
 589                 RDEBUG2("Passing reply back for EAP-MS-CHAP-V2");
 590                 process_post_proxy(0, fake);
 591
 592                 /*
 593                  *      FIXME: If rcode returns fail, do something
 594                  *      intelligent...
 595                  */
 596                 rcode = rad_postauth(fake);
 597
 598                 if ((debug_flag > 0) && fr_log_fp) {
 599                         fprintf(fr_log_fp, "} # server %s\n", fake->server);
 600
 601                         RDEBUG("Final reply from tunneled session code %d",
 602                                fake->reply->code);
 603
 604                         debug_pair_list(fake->reply->vps);
 605                 }
 606
 607                 /*
 608                  *      Terrible hacks.
 609                  */
 610                 request->proxy = fake->packet;
 611                 fake->packet = NULL;
 612                 request->proxy_reply = fake->reply;
 613                 fake->reply = NULL;
 614
 615                 /*
 616                  *      And we're done with this request.
 617                  */
 618
 619                 switch (rcode) {
 620                 case RLM_MODULE_FAIL:
 621                         request_free(&fake);
 622                         eaptls_fail(handler, 0);
 623                         return 0;
 624                         break;
 625
 626                 default:  /* Don't Do Anything */
 627                         RDEBUG2("Got reply %d", request->proxy_reply->code);
 628                         break;
 629                 }
 630         }
 631         request_free(&fake);    /* robust if !fake */
 632
 633         /*
 634          *      If there was no EAP-Message in the reply packet, then
 635          *      we know that we're supposed to re-run the "authenticate"
 636          *      stage, in order to get the right kind of handling...
 637          */
 638
 639         /*
 640          *      Process the reply from the home server.
 641          */
 642
 643         rcode = process_reply(handler, tls_session, handler->request,
 644                               handler->request->proxy_reply);
 645
 646         /*
 647          *      The proxy code uses the reply from the home server as
 648          *      the basis for the reply to the NAS.  We don't want that,
 649          *      so we toss it, after we've had our way with it.
 650          */
 651         pairfree(&handler->request->proxy_reply->vps);
 652
 653         switch (rcode) {
 654         case RLM_MODULE_REJECT:
 655                 RDEBUG2("Reply was rejected");
 656                 eaptls_fail(handler, 0);
 657                 return 0;
 658
 659         case RLM_MODULE_HANDLED:
 660                 RDEBUG2("Reply was handled");
 661                 eaptls_request(handler->eap_ds, tls_session);
 662                 return 1;
 663
 664         case RLM_MODULE_OK:
 665                 RDEBUG2("Reply was OK");
 666
 667                 /*
 668                  *      Success: Automatically return MPPE keys.
 669                  */
 670                 return eaptls_success(handler, 0);
 671
 672         default:
 673                 RDEBUG2("Reply was unknown.");
 674                 break;
 675         }
 676
 677         eaptls_fail(handler, 0);
 678         return 0;
 679 }
 680 #endif
 681
 682
 683 static char const *peap_state(peap_tunnel_t *t)
 684 {
 685         switch (t->status) {
 686                 case PEAP_STATUS_TUNNEL_ESTABLISHED:
 687                         return "TUNNEL ESTABLISHED";
 688                 case PEAP_STATUS_WAIT_FOR_SOH_RESPONSE:
 689                         return "WAITING FOR SOH RESPONSE";
 690                 case PEAP_STATUS_INNER_IDENTITY_REQ_SENT:
 691                         return "WAITING FOR INNER IDENTITY";
 692                 case PEAP_STATUS_SENT_TLV_SUCCESS:
 693                         return "send tlv success";
 694                 case PEAP_STATUS_SENT_TLV_FAILURE:
 695                         return "send tlv failure";
 696                 case PEAP_STATUS_PHASE2_INIT:
 697                         return "phase2_init";
 698                 case PEAP_STATUS_PHASE2:
 699                         return "phase2";
 700                 default:
 701                         break;
 702         }
 703         return "?";
 704 }
 705
 706 static void print_tunneled_data(uint8_t const *data, size_t data_len)
 707 {
 708         size_t i;
 709
 710         if ((debug_flag > 2) && fr_log_fp) {
 711                 for (i = 0; i < data_len; i++) {
 712                   if ((i & 0x0f) == 0) fprintf(fr_log_fp, "  PEAP tunnel data in %02x: ", (int) i);
 713
 714                         fprintf(fr_log_fp, "%02x ", data[i]);
 715
 716                         if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
 717                 }
 718                 if ((data_len & 0x0f) != 0) fprintf(fr_log_fp, "\n");
 719         }
 720 }
 721
 722
 723 /*
 724  *      Process the pseudo-EAP contents of the tunneled data.
 725  */
 726 rlm_rcode_t eappeap_process(eap_handler_t *handler, tls_session_t *tls_session)
 727 {
 728         peap_tunnel_t   *t = tls_session->opaque;
 729         REQUEST         *fake;
 730         VALUE_PAIR      *vp;
 731         rlm_rcode_t     rcode = RLM_MODULE_REJECT;
 732         uint8_t const   *data;
 733         unsigned int    data_len;
 734         char *p;
 735
 736         REQUEST *request = handler->request;
 737         EAP_DS *eap_ds = handler->eap_ds;
 738
 739         rad_assert(request != NULL);
 740
 741         /*
 742          *      Just look at the buffer directly, without doing
 743          *      record_minus.  This lets us avoid another data copy.
 744          */
 745         data_len = tls_session->clean_out.used;
 746         tls_session->clean_out.used = 0;
 747         data = tls_session->clean_out.data;
 748
 749         RDEBUG2("Peap state %s", peap_state(t));
 750
 751         if ((t->status != PEAP_STATUS_TUNNEL_ESTABLISHED) &&
 752             !eapmessage_verify(request, data, data_len)) {
 753                 RDEBUG2("FAILED processing PEAP: Tunneled data is invalid.");
 754                 if (debug_flag > 2) print_tunneled_data(data, data_len);
 755                 return RLM_MODULE_REJECT;
 756         }
 757
 758         switch (t->status) {
 759         case PEAP_STATUS_TUNNEL_ESTABLISHED:
 760                 /* FIXME: should be no data in the buffer here, check & assert? */
 761
 762                 if (SSL_session_reused(tls_session->ssl)) {
 763                         RDEBUG2("Skipping Phase2 because of session resumption");
 764                         t->session_resumption_state = PEAP_RESUMPTION_YES;
 765                         if (t->soh) {
 766                                 t->status = PEAP_STATUS_WAIT_FOR_SOH_RESPONSE;
 767                                 RDEBUG2("Requesting SoH from client");
 768                                 eappeap_soh(handler, tls_session);
 769                                 return RLM_MODULE_HANDLED;
 770                         }
 771                         /* we're good, send success TLV */
 772                         t->status = PEAP_STATUS_SENT_TLV_SUCCESS;
 773                         eappeap_success(handler, tls_session);
 774
 775                 } else {
 776                         /* send an identity request */
 777                         t->session_resumption_state = PEAP_RESUMPTION_NO;
 778                         t->status = PEAP_STATUS_INNER_IDENTITY_REQ_SENT;
 779                         eappeap_identity(handler, tls_session);
 780                 }
 781                 return RLM_MODULE_HANDLED;
 782
 783         case PEAP_STATUS_INNER_IDENTITY_REQ_SENT:
 784                 /* we're expecting an identity response */
 785                 if (data[0] != PW_EAP_IDENTITY) {
 786                         RDEBUG("Expected EAP-Identity, got something else.");
 787                         return RLM_MODULE_REJECT;
 788                 }
 789
 790                 /*
 791                  *      Save it for later.
 792                  */
 793                 t->username = pairmake(t, NULL, "User-Name", NULL, T_OP_EQ);
 794                 rad_assert(t->username != NULL);
 795
 796                 t->username->vp_strvalue = p = talloc_array(t->username, char, data_len);
 797                 memcpy(p, data + 1, data_len - 1);
 798                 t->username->length = data_len - 1;
 799                 p[t->username->length] = 0;
 800                 RDEBUG("Got inner identity '%s'", t->username->vp_strvalue);
 801                 if (t->soh) {
 802                         t->status = PEAP_STATUS_WAIT_FOR_SOH_RESPONSE;
 803                         RDEBUG2("Requesting SoH from client");
 804                         eappeap_soh(handler, tls_session);
 805                         return RLM_MODULE_HANDLED;
 806                 }
 807                 t->status = PEAP_STATUS_PHASE2_INIT;
 808                 break;
 809
 810         case PEAP_STATUS_WAIT_FOR_SOH_RESPONSE:
 811                 fake = request_alloc_fake(request);
 812                 rad_assert(!fake->packet->vps);
 813                 eapsoh_verify(request, fake->packet, data, data_len);
 814                 setup_fake_request(request, fake, t);
 815
 816                 if (t->soh_virtual_server) {
 817                         fake->server = t->soh_virtual_server;
 818                 }
 819                 RDEBUG("Sending SoH request to server %s", fake->server ? fake->server : "NULL");
 820                 debug_pair_list(fake->packet->vps);
 821                 RDEBUG("server %s {", fake->server);
 822                 rad_virtual_server(fake);
 823                 RDEBUG("} # server %s", fake->server);
 824                 RDEBUG("Got SoH reply");
 825                 debug_pair_list(fake->reply->vps);
 826
 827                 if (fake->reply->code != PW_AUTHENTICATION_ACK) {
 828                         RDEBUG2("SoH was rejected");
 829                         request_free(&fake);
 830                         t->status = PEAP_STATUS_SENT_TLV_FAILURE;
 831                         eappeap_failure(handler, tls_session);
 832                         return RLM_MODULE_HANDLED;
 833                 }
 834
 835                 /* save the SoH VPs */
 836                 rad_assert(!t->soh_reply_vps);
 837                 pairfilter(t, &t->soh_reply_vps, &fake->reply->vps, 0, 0, TAG_ANY);
 838                 rad_assert(!fake->reply->vps);
 839                 request_free(&fake);
 840
 841                 if (t->session_resumption_state == PEAP_RESUMPTION_YES) {
 842                         /* we're good, send success TLV */
 843                         t->status = PEAP_STATUS_SENT_TLV_SUCCESS;
 844                         eappeap_success(handler, tls_session);
 845                         return RLM_MODULE_HANDLED;
 846                 }
 847
 848                 t->status = PEAP_STATUS_PHASE2_INIT;
 849                 break;
 850
 851
 852         /*
 853          *      If we authenticated the user, then it's OK.
 854          */
 855         case PEAP_STATUS_SENT_TLV_SUCCESS:
 856                 if (eappeap_check_tlv(request, data, data_len)) {
 857                         RDEBUG2("Success");
 858                         return RLM_MODULE_OK;
 859                 }
 860
 861                 /*
 862                  *      Otherwise, the client rejected the session
 863                  *      resumption.  If the session is being re-used,
 864                  *      we need to do a full authentication.
 865                  *
 866                  *      We do this by sending an EAP-Identity request
 867                  *      inside of the PEAP tunnel.
 868                  */
 869                 if (t->session_resumption_state == PEAP_RESUMPTION_YES) {
 870                         RDEBUG2("Client rejected session resumption.  Re-starting full authentication");
 871
 872                         /*
 873                          *      Mark session resumption status.
 874                          */
 875                         t->status = PEAP_STATUS_INNER_IDENTITY_REQ_SENT;
 876                         t->session_resumption_state = PEAP_RESUMPTION_NO;
 877
 878                         eappeap_identity(handler, tls_session);
 879                         return RLM_MODULE_HANDLED;
 880                 }
 881
 882                 RDEBUG2("We sent a success, but received something weird in return.");
 883                 return RLM_MODULE_REJECT;
 884
 885         /*
 886          *      Damned if I know why the clients continue sending EAP
 887          *      packets after we told them to f*ck off.
 888          */
 889         case PEAP_STATUS_SENT_TLV_FAILURE:
 890                 RDEBUG(" The users session was previously rejected: returning reject (again.)");
 891                 RDEBUG(" *** This means you need to read the PREVIOUS messages in the debug output");
 892                 RDEBUG(" *** to find out the reason why the user was rejected.");
 893                 RDEBUG(" *** Look for \"reject\" or \"fail\".  Those earlier messages will tell you.");
 894                 RDEBUG(" *** what went wrong, and how to fix the problem.");
 895                 return RLM_MODULE_REJECT;
 896
 897                 case PEAP_STATUS_PHASE2_INIT:
 898                         RDEBUG("In state machine in phase2 init?");
 899
 900                 case PEAP_STATUS_PHASE2:
 901                         break;
 902
 903                 default:
 904                         RDEBUG2("Unhandled state in peap");
 905                         return RLM_MODULE_REJECT;
 906         }
 907
 908         fake = request_alloc_fake(request);
 909
 910         rad_assert(!fake->packet->vps);
 911
 912         switch (t->status) {
 913                 /*
 914                  *      If we're in PHASE2_INIT, the phase2 method hasn't been
 915                  *      sent an Identity packet yet; do so from the stored
 916                  *      username and this will kick off the phase2 eap method
 917                  */
 918
 919         case PEAP_STATUS_PHASE2_INIT: {
 920                 size_t len = t->username->length + EAP_HEADER_LEN + 1;
 921                 uint8_t *q;
 922
 923                 t->status = PEAP_STATUS_PHASE2;
 924
 925                 vp = paircreate(fake->packet, PW_EAP_MESSAGE, 0);
 926                 vp->length = len;
 927                 vp->vp_octets = q = talloc_array(vp, uint8_t, vp->length);
 928
 929                 q[0] = PW_EAP_RESPONSE;
 930                 q[1] = eap_ds->response->id;
 931                 q[2] = (len >> 8) & 0xff;
 932                 q[3] = len & 0xff;
 933                 q[4] = PW_EAP_IDENTITY;
 934
 935                 memcpy(q + EAP_HEADER_LEN + 1,
 936                        t->username->vp_strvalue, t->username->length);
 937
 938                 pairadd(&fake->packet->vps, vp);
 939
 940                 if (t->default_method != 0) {
 941                         RDEBUG2("Setting default EAP type for tunneled EAP session.");
 942                         vp = pairmake(fake, &fake->config_items, "EAP-Type", "0", T_OP_EQ);
 943                         vp->vp_integer = t->default_method;
 944                 }
 945                 break; }
 946
 947         case PEAP_STATUS_PHASE2:
 948                 fake->packet->vps = eap2vp(request, fake->packet,
 949                                            eap_ds, data, data_len);
 950                 if (!fake->packet->vps) {
 951                         request_free(&fake);
 952                         RDEBUG2("Unable to convert tunneled EAP packet to internal server data structures");
 953                         return RLM_MODULE_REJECT;
 954                 }
 955                 break;
 956
 957         default:
 958                 RDEBUG("Invalid state change in PEAP");
 959                 return RLM_MODULE_REJECT;
 960         }
 961
 962         if ((debug_flag > 0) && fr_log_fp) {
 963                 RDEBUG("Got tunneled request");
 964
 965                 debug_pair_list(fake->packet->vps);
 966
 967                 fprintf(fr_log_fp, "server %s {\n",
 968                         (!fake->server) ? "" : fake->server);
 969         }
 970
 971         /*
 972          *      Update other items in the REQUEST data structure.
 973          */
 974         if (!t->username) {
 975                 /*
 976                  *      There's no User-Name in the tunneled session,
 977                  *      so we add one here, by pulling it out of the
 978                  *      EAP-Identity packet.
 979                  */
 980                 if ((data[0] == PW_EAP_IDENTITY) && (data_len > 1)) {
 981                         t->username = pairmake(t, NULL, "User-Name", NULL, T_OP_EQ);
 982                         rad_assert(t->username != NULL);
 983
 984                         t->username->vp_strvalue = p = talloc_array(t->username, char, data_len);
 985                         memcpy(p, data + 1, data_len - 1);
 986                         t->username->length = data_len - 1;
 987                         p[t->username->length] = 0;
 988                         DEBUG2("  PEAP: Got tunneled identity of %s", t->username->vp_strvalue);
 989
 990                         /*
 991                          *      If there's a default EAP type,
 992                          *      set it here.
 993                          */
 994                         if (t->default_method != 0) {
 995                                 DEBUG2("  PEAP: Setting default EAP type for tunneled EAP session.");
 996                                 vp = pairmake(fake, &fake->config_items, "EAP-Type", "0", T_OP_EQ);
 997                                 vp->vp_integer = t->default_method;
 998                         }
 999                 }
1000         } /* else there WAS a t->username */
1001
1002         setup_fake_request(request, fake, t);
1003
1004         if ((vp = pairfind(request->config_items, PW_VIRTUAL_SERVER, 0, TAG_ANY)) != NULL) {
1005                 fake->server = vp->vp_strvalue;
1006
1007         } else if (t->virtual_server) {
1008                 fake->server = t->virtual_server;
1009
1010         } /* else fake->server == request->server */
1011
1012         if ((debug_flag > 0) && fr_log_fp) {
1013                 fprintf(fr_log_fp, "Sending tunneled request\n");
1014
1015                 debug_pair_list(fake->packet->vps);
1016
1017                 fprintf(fr_log_fp, "server %s {\n",
1018                         (!fake->server) ? "" : fake->server);
1019         }
1020
1021         /*
1022          *      Call authentication recursively, which will
1023          *      do PAP, CHAP, MS-CHAP, etc.
1024          */
1025         rad_virtual_server(fake);
1026
1027         /*
1028          *      Note that we don't do *anything* with the reply
1029          *      attributes.
1030          */
1031         if ((debug_flag > 0) && fr_log_fp) {
1032                 fprintf(fr_log_fp, "} # server %s\n",
1033                         (!fake->server) ? "" : fake->server);
1034
1035                 RDEBUG("Got tunneled reply code %d", fake->reply->code);
1036
1037                 debug_pair_list(fake->reply->vps);
1038         }
1039
1040         /*
1041          *      Decide what to do with the reply.
1042          */
1043         switch (fake->reply->code) {
1044         case 0:                 /* No reply code, must be proxied... */
1045 #ifdef WITH_PROXY
1046                 vp = pairfind(fake->config_items, PW_PROXY_TO_REALM, 0, TAG_ANY);
1047
1048                 if (vp) {
1049                         eap_tunnel_data_t *tunnel;
1050
1051                         /*
1052                          *      The tunneled request was NOT handled,
1053                          *      it has to be proxied.  This means that
1054                          *      the "authenticate" stage was never
1055                          *      performed.
1056                          *
1057                          *      If we are told to NOT proxy the
1058                          *      tunneled request as EAP, then this
1059                          *      means that we've got to decode it,
1060                          *      which means that we MUST run the
1061                          *      "authenticate" portion by hand, here.
1062                          *
1063                          *      Once the tunneled EAP session is ALMOST
1064                          *      done, THEN we proxy it...
1065                          */
1066                         if (!t->proxy_tunneled_request_as_eap) {
1067                                 fake->options |= RAD_REQUEST_OPTION_PROXY_EAP;
1068
1069                                 /*
1070                                  *      Hmm... should we check for
1071                                  *      Auth-Type & EAP-Message here?
1072                                  */
1073
1074
1075                                 /*
1076                                  *      Run the EAP authentication.
1077                                  */
1078                                 DEBUG2("  PEAP: Calling authenticate in order to initiate tunneled EAP session.");
1079                                 rcode = process_authenticate(PW_AUTHTYPE_EAP, fake);
1080                                 if (rcode == RLM_MODULE_OK) {
1081                                         /*
1082                                          *      Authentication succeeded! Rah!
1083                                          */
1084                                         fake->reply->code = PW_AUTHENTICATION_ACK;
1085                                         goto do_process;
1086                                 }
1087
1088                                 if (rcode != RLM_MODULE_HANDLED) {
1089                                         DEBUG2("  PEAP: Can't handle the return code %d", rcode);
1090                                         rcode = RLM_MODULE_REJECT;
1091                                         goto done;
1092                                 }
1093
1094                                 /*
1095                                  *      The module decided it wasn't
1096                                  *      done.  Handle it like normal.
1097                                  */
1098                                 if ((fake->options & RAD_REQUEST_OPTION_PROXY_EAP) == 0) {
1099                                         DEBUG2("    PEAP: Cancelling proxy to realm %s until the tunneled EAP session has been established", vp->vp_strvalue);
1100                                         goto do_process;
1101                                 }
1102
1103                                 /*
1104                                  *      The module has decoded the
1105                                  *      EAP-Message into another set
1106                                  *      of attributes.
1107                                  */
1108                                 pairdelete(&fake->packet->vps,
1109                                            PW_EAP_MESSAGE, 0, TAG_ANY);
1110                         }
1111
1112                         DEBUG2("  PEAP: Tunneled authentication will be proxied to %s", vp->vp_strvalue);
1113
1114                         /*
1115                          *      Tell the original request that it's going
1116                          *      to be proxied.
1117                          */
1118                         pairfilter(request, &(request->config_items),
1119                                    &(fake->config_items),
1120                                    PW_PROXY_TO_REALM, 0, TAG_ANY);
1121
1122                         /*
1123                          *      Seed the proxy packet with the
1124                          *      tunneled request.
1125                          */
1126                         rad_assert(!request->proxy);
1127                         request->proxy = fake->packet;
1128                         memset(&request->proxy->src_ipaddr, 0,
1129                                sizeof(request->proxy->src_ipaddr));
1130                         memset(&request->proxy->dst_ipaddr, 0,
1131                                sizeof(request->proxy->dst_ipaddr));
1132                         request->proxy->src_port = 0;
1133                         request->proxy->dst_port = 0;
1134                         fake->packet = NULL;
1135                         rad_free(&fake->reply);
1136                         fake->reply = NULL;
1137
1138                         /*
1139                          *      Set up the callbacks for the tunnel
1140                          */
1141                         tunnel = talloc_zero(request, eap_tunnel_data_t);
1142                         tunnel->tls_session = tls_session;
1143                         tunnel->callback = eappeap_postproxy;
1144
1145                         /*
1146                          *      Associate the callback with the request.
1147                          */
1148                         rcode = request_data_add(request,
1149                                                  request->proxy,
1150                                                  REQUEST_DATA_EAP_TUNNEL_CALLBACK,
1151                                                  tunnel, false);
1152                         rad_assert(rcode == 0);
1153
1154                         /*
1155                          *      We're not proxying it as EAP, so we've got
1156                          *      to do the callback later.
1157                          */
1158                         if ((fake->options & RAD_REQUEST_OPTION_PROXY_EAP) != 0) {
1159                                 DEBUG2("  PEAP: Remembering to do EAP-MS-CHAP-V2 post-proxy.");
1160
1161                                 /*
1162                                  *      rlm_eap.c has taken care of associating
1163                                  *      the handler with the fake request.
1164                                  *
1165                                  *      So we associate the fake request with
1166                                  *      this request.
1167                                  */
1168                                 talloc_set_destructor(fake, request_opaque_free);
1169                                 rcode = request_data_add(request, request->proxy,
1170                                                          REQUEST_DATA_EAP_MSCHAP_TUNNEL_CALLBACK,
1171                                                          fake, true);
1172                                 rad_assert(rcode == 0);
1173
1174                                 /*
1175                                  *      Do NOT free the fake request!
1176                                  */
1177                                 return RLM_MODULE_UPDATED;
1178                         }
1179
1180                         /*
1181                          *      Didn't authenticate the packet, but
1182                          *      we're proxying it.
1183                          */
1184                         rcode = RLM_MODULE_UPDATED;
1185
1186                 } else
1187 #endif  /* WITH_PROXY */
1188                   {
1189                         DEBUG2("  PEAP: Unknown RADIUS packet type %d: rejecting tunneled user", fake->reply->code);
1190                         rcode = RLM_MODULE_REJECT;
1191                   }
1192                 break;
1193
1194         default:
1195 #ifdef WITH_PROXY
1196         do_process:
1197 #endif
1198                 rcode = process_reply(handler, tls_session, request,
1199                                       fake->reply);
1200                 break;
1201         }
1202
1203 #ifdef WITH_PROXY
1204  done:
1205 #endif
1206         request_free(&fake);
1207
1208         return rcode;
1209 }
1210
1211 static int setup_fake_request(REQUEST *request, REQUEST *fake, peap_tunnel_t *t) {
1212
1213         VALUE_PAIR *vp;
1214         /*
1215          *      Tell the request that it's a fake one.
1216          */
1217         pairmake(fake->packet, &fake->packet->vps,
1218                  "Freeradius-Proxied-To", "127.0.0.1", T_OP_EQ);
1219
1220         if (t->username) {
1221                 vp = paircopy(fake->packet, t->username);
1222                 pairadd(&fake->packet->vps, vp);
1223                 fake->username = vp;
1224                 RDEBUG2("Setting User-Name to %s", fake->username->vp_strvalue);
1225         } else {
1226                 RDEBUG2("No tunnel username (SSL resumption?)");
1227         }
1228
1229
1230         /*
1231          *      Add the State attribute, too, if it exists.
1232          */
1233         if (t->state) {
1234                 vp = paircopy(fake->packet, t->state);
1235                 if (vp) pairadd(&fake->packet->vps, vp);
1236         }
1237
1238         /*
1239          *      If this is set, we copy SOME of the request attributes
1240          *      from outside of the tunnel to inside of the tunnel.
1241          *
1242          *      We copy ONLY those attributes which do NOT already
1243          *      exist in the tunneled request.
1244          *
1245          *      This code is copied from ../rlm_eap_ttls/ttls.c
1246          */
1247         if (t->copy_request_to_tunnel) {
1248                 VALUE_PAIR *copy;
1249                 vp_cursor_t cursor;
1250
1251                 for (vp = fr_cursor_init(&cursor, &request->packet->vps);
1252                      vp;
1253                      vp = fr_cursor_next(&cursor)) {
1254                         /*
1255                          *      The attribute is a server-side thingy,
1256                          *      don't copy it.
1257                          */
1258                         if ((vp->da->attr > 255) && (((vp->da->attr >> 16) & 0xffff) == 0)) {
1259                                 continue;
1260                         }
1261
1262                         /*
1263                          *      The outside attribute is already in the
1264                          *      tunnel, don't copy it.
1265                          *
1266                          *      This works for BOTH attributes which
1267                          *      are originally in the tunneled request,
1268                          *      AND attributes which are copied there
1269                          *      from below.
1270                          */
1271                         if (pairfind(fake->packet->vps, vp->da->attr, vp->da->vendor, TAG_ANY)) {
1272                                 continue;
1273                         }
1274
1275                         /*
1276                          *      Some attributes are handled specially.
1277                          */
1278                         switch (vp->da->attr) {
1279                                 /*
1280                                  *      NEVER copy Message-Authenticator,
1281                                  *      EAP-Message, or State.  They're
1282                                  *      only for outside of the tunnel.
1283                                  */
1284                         case PW_USER_NAME:
1285                         case PW_USER_PASSWORD:
1286                         case PW_CHAP_PASSWORD:
1287                         case PW_CHAP_CHALLENGE:
1288                         case PW_PROXY_STATE:
1289                         case PW_MESSAGE_AUTHENTICATOR:
1290                         case PW_EAP_MESSAGE:
1291                         case PW_STATE:
1292                                 continue;
1293                                 break;
1294
1295                                 /*
1296                                  *      By default, copy it over.
1297                                  */
1298                         default:
1299                                 break;
1300                         }
1301
1302                         /*
1303                          *      Don't copy from the head, we've already
1304                          *      checked it.
1305                          */
1306                         copy = paircopy2(fake->packet, vp, vp->da->attr, vp->da->vendor, TAG_ANY);
1307                         pairadd(&fake->packet->vps, copy);
1308                 }
1309         }
1310
1311         return 0;
1312 }