src/modules/rlm_eap/types/rlm_eap_ttls/ttls.c

   1 /*
   2  * rlm_eap_ttls.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 "eap_ttls.h"
  28
  29 /*
  30  *    0                   1                   2                   3
  31  *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  32  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  33  *   |                           AVP Code                            |
  34  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  35  *   |V M r r r r r r|                  AVP Length                   |
  36  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  37  *   |                        Vendor-ID (opt)                        |
  38  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  39  *   |    Data ...
  40  *   +-+-+-+-+-+-+-+-+
  41  */
  42
  43 /*
  44  *      Verify that the diameter packet is valid.
  45  */
  46 static int diameter_verify(REQUEST *request,
  47                            const uint8_t *data, unsigned int data_len)
  48 {
  49         uint32_t attr;
  50         uint32_t length;
  51         unsigned int offset;
  52         unsigned int data_left = data_len;
  53
  54         while (data_left > 0) {
  55                 if (data_len < 12) {
  56                         RDEBUG2(" Diameter attribute is too small to contain a Diameter header");
  57                         return 0;
  58                 }
  59
  60                 rad_assert(data_left <= data_len);
  61                 memcpy(&attr, data, sizeof(attr));
  62                 data += 4;
  63                 attr = ntohl(attr);
  64                 if (attr > 255) {
  65                         RDEBUG2(" Non-RADIUS attribute in tunneled authentication is not supported");
  66                         return 0;
  67                 }
  68
  69                 memcpy(&length, data , sizeof(length));
  70                 data += 4;
  71                 length = ntohl(length);
  72
  73                 /*
  74                  *      A "vendor" flag, with a vendor ID of zero,
  75                  *      is equivalent to no vendor.  This is stupid.
  76                  */
  77                 offset = 8;
  78                 if ((length & (1 << 31)) != 0) {
  79                         int attribute;
  80                         uint32_t vendor;
  81                         DICT_ATTR *da;
  82
  83                         memcpy(&vendor, data, sizeof(vendor));
  84                         vendor = ntohl(vendor);
  85
  86                         if (vendor > 65535) {
  87                                 RDEBUG2("Vendor codes larger than 65535 are not supported");
  88                                 return 0;
  89                         }
  90
  91                         attribute = (vendor << 16) | attr;
  92
  93                         da = dict_attrbyvalue(attribute);
  94
  95                         /*
  96                          *      SHOULD check ((length & (1 << 30)) != 0)
  97                          *      for the mandatory bit.
  98                          */
  99                         if (!da) {
 100                                 RDEBUG2("Fatal! Vendor %u, Attribute %u was not found in our dictionary. ",
 101                                        vendor, attr);
 102                                 return 0;
 103                         }
 104
 105                         data += 4; /* skip the vendor field */
 106                         offset += 4; /* offset to value field */
 107                 }
 108
 109                 /*
 110                  *      Ignore the M bit.  We support all RADIUS attributes...
 111                  */
 112
 113                 /*
 114                  *      Get the length.  If it's too big, die.
 115                  */
 116                 length &= 0x00ffffff;
 117
 118                 /*
 119                  *      Too short or too long is bad.
 120                  */
 121                 if (length < offset) {
 122                         RDEBUG2("Tunneled attribute %d is too short (%d)to contain anything useful.", attr, length);
 123                         return 0;
 124                 }
 125
 126                 /*
 127                  *      EAP Messages cane be longer than MAX_STRING_LEN.
 128                  *      Other attributes cannot be.
 129                  */
 130                 if ((attr != PW_EAP_MESSAGE) &&
 131                     (length > (MAX_STRING_LEN + 8))) {
 132                         RDEBUG2("Tunneled attribute %d is too long (%d) to pack into a RADIUS attribute.", attr, length);
 133                         return 0;
 134                 }
 135
 136                 if (length > data_left) {
 137                         RDEBUG2("Tunneled attribute %d is longer than room left in the packet (%d > %d).", attr, length, data_left);
 138                         return 0;
 139                 }
 140
 141                 /*
 142                  *      Check for broken implementations, which don't
 143                  *      pad the AVP to a 4-octet boundary.
 144                  */
 145                 if (data_left == length) break;
 146
 147                 /*
 148                  *      The length does NOT include the padding, so
 149                  *      we've got to account for it here by rounding up
 150                  *      to the nearest 4-byte boundary.
 151                  */
 152                 length += 0x03;
 153                 length &= ~0x03;
 154
 155                 /*
 156                  *      If the rest of the diameter packet is larger than
 157                  *      this attribute, continue.
 158                  *
 159                  *      Otherwise, if the attribute over-flows the end
 160                  *      of the packet, die.
 161                  */
 162                 if (data_left < length) {
 163                         RDEBUG2("ERROR! Diameter attribute overflows packet!");
 164                         return 0;
 165                 }
 166
 167                 /*
 168                  *      Check again for equality, now that we're padded
 169                  *      length to a multiple of 4 octets.
 170                  */
 171                 if (data_left == length) break;
 172
 173                 /*
 174                  *      data_left > length, continue.
 175                  */
 176                 data_left -= length;
 177                 data += length - offset;
 178         }
 179
 180         /*
 181          *      We got this far.  It looks OK.
 182          */
 183         return 1;
 184 }
 185
 186
 187 /*
 188  *      Convert diameter attributes to our VALUE_PAIR's
 189  */
 190 static VALUE_PAIR *diameter2vp(REQUEST *request, SSL *ssl,
 191                                const uint8_t *data, size_t data_len)
 192 {
 193         uint32_t        attr;
 194         uint32_t        length;
 195         size_t          offset;
 196         size_t          size;
 197         size_t          data_left = data_len;
 198         VALUE_PAIR      *first = NULL;
 199         VALUE_PAIR      **last = &first;
 200         VALUE_PAIR      *vp;
 201
 202         while (data_left > 0) {
 203                 rad_assert(data_left <= data_len);
 204                 memcpy(&attr, data, sizeof(attr));
 205                 data += 4;
 206                 attr = ntohl(attr);
 207
 208                 memcpy(&length, data, sizeof(length));
 209                 data += 4;
 210                 length = ntohl(length);
 211
 212                 /*
 213                  *      A "vendor" flag, with a vendor ID of zero,
 214                  *      is equivalent to no vendor.  This is stupid.
 215                  */
 216                 offset = 8;
 217                 if ((length & (1 << 31)) != 0) {
 218                         uint32_t vendor;
 219
 220                         memcpy(&vendor, data, sizeof(vendor));
 221                         vendor = ntohl(vendor);
 222
 223                         if (attr > 65535) {
 224                                 RDEBUG2("Cannot handle vendor attributes greater than 65535");
 225                                 pairfree(&first);
 226                                 return NULL;
 227                         }
 228
 229                         if (vendor > 65535) {
 230                                 RDEBUG2("Cannot handle vendor Id greater than 65535");
 231                                 pairfree(&first);
 232                                 return NULL;
 233                         }
 234
 235                         attr |= (vendor << 16);
 236
 237                         data += 4; /* skip the vendor field, it's zero */
 238                         offset += 4; /* offset to value field */
 239                 }
 240
 241                 /*
 242                  *      Vendor attributes can be larger than 255.
 243                  *      Normal attributes cannot be.
 244                  */
 245                 if ((attr > 255) && (VENDOR(attr) == 0)) {
 246                         RDEBUG2("Cannot handle Diameter attributes");
 247                         pairfree(&first);
 248                         return NULL;
 249                 }
 250
 251                 /*
 252                  *      FIXME: Handle the M bit.  For now, we assume that
 253                  *      some other module takes care of any attribute
 254                  *      with the M bit set.
 255                  */
 256
 257                 /*
 258                  *      Get the length.
 259                  */
 260                 length &= 0x00ffffff;
 261
 262                 /*
 263                  *      Get the size of the value portion of the
 264                  *      attribute.
 265                  */
 266                 size = length - offset;
 267
 268                 /*
 269                  *      Create it.
 270                  */
 271                 vp = paircreate(attr, PW_TYPE_OCTETS);
 272                 if (!vp) {
 273                         RDEBUG2("Failure in creating VP");
 274                         pairfree(&first);
 275                         return NULL;
 276                 }
 277
 278                 /*
 279                  *      If it's a type from our dictionary, then
 280                  *      we need to put the data in a relevant place.
 281                  */
 282                 switch (vp->type) {
 283                 case PW_TYPE_INTEGER:
 284                 case PW_TYPE_DATE:
 285                         if (size != vp->length) {
 286                                 RDEBUG2("Invalid length attribute %d",
 287                                        attr);
 288                                 pairfree(&first);
 289                                 pairfree(&vp);
 290                                 return NULL;
 291                         }
 292                         memcpy(&vp->vp_integer, data, vp->length);
 293
 294                         /*
 295                          *      Stored in host byte order: change it.
 296                          */
 297                         vp->vp_integer = ntohl(vp->vp_integer);
 298                         break;
 299
 300                 case PW_TYPE_IPADDR:
 301                         if (size != vp->length) {
 302                                 RDEBUG2("Invalid length attribute %d",
 303                                        attr);
 304                                 pairfree(&first);
 305                                 pairfree(&vp);
 306                                 return NULL;
 307                         }
 308                   memcpy(&vp->vp_ipaddr, data, vp->length);
 309
 310                   /*
 311                    *    Stored in network byte order: don't change it.
 312                    */
 313                   break;
 314
 315                   /*
 316                    *    String, octet, etc.  Copy the data from the
 317                    *    value field over verbatim.
 318                    *
 319                    *    FIXME: Ipv6 attributes ?
 320                    *
 321                    */
 322                 case PW_TYPE_OCTETS:
 323                         if (attr == PW_EAP_MESSAGE) {
 324                                 const uint8_t *eap_message = data;
 325
 326                                 /*
 327                                  *      vp exists the first time around.
 328                                  */
 329                                 while (1) {
 330                                         vp->length = size;
 331                                         if (vp->length > 253) vp->length = 253;
 332                                         memcpy(vp->vp_octets, eap_message,
 333                                                vp->length);
 334
 335                                         size -= vp->length;
 336                                         eap_message += vp->length;
 337
 338                                         *last = vp;
 339                                         last = &(vp->next);
 340
 341                                         if (size == 0) break;
 342
 343                                         vp = paircreate(attr, PW_TYPE_OCTETS);
 344                                         if (!vp) {
 345                                                 RDEBUG2("Failure in creating VP");
 346                                                 pairfree(&first);
 347                                                 return NULL;
 348                                         }
 349                                 }
 350
 351                                 goto next_attr;
 352                         } /* else it's another kind of attribute */
 353                         /* FALL-THROUGH */
 354
 355                 default:
 356                         vp->length = size;
 357                         memcpy(vp->vp_strvalue, data, vp->length);
 358                         break;
 359                 }
 360
 361                 /*
 362                  *      User-Password is NUL padded to a multiple
 363                  *      of 16 bytes.  Let's chop it to something
 364                  *      more reasonable.
 365                  *
 366                  *      NOTE: This means that the User-Password
 367                  *      attribute CANNOT EVER have embedded zeros in it!
 368                  */
 369                 switch (vp->attribute) {
 370                 case PW_USER_PASSWORD:
 371                         /*
 372                          *      If the password is exactly 16 octets,
 373                          *      it won't be zero-terminated.
 374                          */
 375                         vp->vp_strvalue[vp->length] = '\0';
 376                         vp->length = strlen(vp->vp_strvalue);
 377                         break;
 378
 379                         /*
 380                          *      Ensure that the client is using the
 381                          *      correct challenge.  This weirdness is
 382                          *      to protect against against replay
 383                          *      attacks, where anyone observing the
 384                          *      CHAP exchange could pose as that user,
 385                          *      by simply choosing to use the same
 386                          *      challenge.
 387                          *
 388                          *      By using a challenge based on
 389                          *      information from the current session,
 390                          *      we can guarantee that the client is
 391                          *      not *choosing* a challenge.
 392                          *
 393                          *      We're a little forgiving in that we
 394                          *      have loose checks on the length, and
 395                          *      we do NOT check the Id (first octet of
 396                          *      the response to the challenge)
 397                          *
 398                          *      But if the client gets the challenge correct,
 399                          *      we're not too worried about the Id.
 400                          */
 401                 case PW_CHAP_CHALLENGE:
 402                 case PW_MSCHAP_CHALLENGE:
 403                         if ((vp->length < 8) ||
 404                             (vp->length > 16)) {
 405                                 RDEBUG("Tunneled challenge has invalid length");
 406                                 pairfree(&first);
 407                                 pairfree(&vp);
 408                                 return NULL;
 409
 410                         } else {
 411                                 uint8_t challenge[16];
 412
 413                                 eapttls_gen_challenge(ssl, challenge,
 414                                                       sizeof(challenge));
 415
 416                                 if (memcmp(challenge, vp->vp_octets,
 417                                            vp->length) != 0) {
 418                                         RDEBUG("Tunneled challenge is incorrect");
 419                                         pairfree(&first);
 420                                         pairfree(&vp);
 421                                         return NULL;
 422                                 }
 423                         }
 424                         break;
 425
 426                 default:
 427                         break;
 428                 } /* switch over checking/re-writing of attributes. */
 429
 430                 /*
 431                  *      Update the list.
 432                  */
 433                 *last = vp;
 434                 last = &(vp->next);
 435
 436         next_attr:
 437                 /*
 438                  *      Catch non-aligned attributes.
 439                  */
 440                 if (data_left == length) break;
 441
 442                 /*
 443                  *      The length does NOT include the padding, so
 444                  *      we've got to account for it here by rounding up
 445                  *      to the nearest 4-byte boundary.
 446                  */
 447                 length += 0x03;
 448                 length &= ~0x03;
 449
 450                 rad_assert(data_left >= length);
 451                 data_left -= length;
 452                 data += length - offset; /* already updated */
 453         }
 454
 455         /*
 456          *      We got this far.  It looks OK.
 457          */
 458         return first;
 459 }
 460
 461 /*
 462  *      Convert VALUE_PAIR's to diameter attributes, and write them
 463  *      to an SSL session.
 464  *
 465  *      The ONLY VALUE_PAIR's which may be passed to this function
 466  *      are ones which can go inside of a RADIUS (i.e. diameter)
 467  *      packet.  So no server-configuration attributes, or the like.
 468  */
 469 static int vp2diameter(REQUEST *request, tls_session_t *tls_session, VALUE_PAIR *first)
 470 {
 471         /*
 472          *      RADIUS packets are no more than 4k in size, so if
 473          *      we've got more than 4k of data to write, it's very
 474          *      bad.
 475          */
 476         uint8_t         buffer[4096];
 477         uint8_t         *p;
 478         uint32_t        attr;
 479         uint32_t        length;
 480         uint32_t        vendor;
 481         size_t          total;
 482         VALUE_PAIR      *vp;
 483
 484         p = buffer;
 485         total = 0;
 486
 487         for (vp = first; vp != NULL; vp = vp->next) {
 488                 /*
 489                  *      Too much data: die.
 490                  */
 491                 if ((total + vp->length + 12) >= sizeof(buffer)) {
 492                         RDEBUG2("output buffer is full!");
 493                         return 0;
 494                 }
 495
 496                 /*
 497                  *      Hmm... we don't group multiple EAP-Messages
 498                  *      together.  Maybe we should...
 499                  */
 500
 501                 /*
 502                  *      Length is no more than 253, due to RADIUS
 503                  *      issues.
 504                  */
 505                 length = vp->length;
 506                 vendor = (vp->attribute >> 16) & 0xffff;
 507                 if (vendor != 0) {
 508                         attr = vp->attribute & 0xffff;
 509                         length |= (1 << 31);
 510                 } else {
 511                         attr = vp->attribute;
 512                 }
 513
 514                 /*
 515                  *      Hmm... set the M bit for all attributes?
 516                  */
 517                 length |= (1 << 30);
 518
 519                 attr = ntohl(attr);
 520
 521                 memcpy(p, &attr, sizeof(attr));
 522                 p += 4;
 523                 total += 4;
 524
 525                 length += 8;    /* includes 8 bytes of attr & length */
 526
 527                 if (vendor != 0) {
 528                         length += 4; /* include 4 bytes of vendor */
 529
 530                         length = ntohl(length);
 531                         memcpy(p, &length, sizeof(length));
 532                         p += 4;
 533                         total += 4;
 534
 535                         vendor = ntohl(vendor);
 536                         memcpy(p, &vendor, sizeof(vendor));
 537                         p += 4;
 538                         total += 4;
 539                 } else {
 540                         length = ntohl(length);
 541                         memcpy(p, &length, sizeof(length));
 542                         p += 4;
 543                         total += 4;
 544                 }
 545
 546                 switch (vp->type) {
 547                 case PW_TYPE_INTEGER:
 548                 case PW_TYPE_DATE:
 549                         attr = ntohl(vp->vp_integer); /* stored in host order */
 550                         memcpy(p, &attr, sizeof(attr));
 551                         length = 4;
 552                         break;
 553
 554                 case PW_TYPE_IPADDR:
 555                         memcpy(p, &vp->vp_ipaddr, 4); /* network order */
 556                         length = 4;
 557                         break;
 558
 559                 case PW_TYPE_STRING:
 560                 case PW_TYPE_OCTETS:
 561                 default:
 562                         memcpy(p, vp->vp_strvalue, vp->length);
 563                         length = vp->length;
 564                         break;
 565                 }
 566
 567                 /*
 568                  *      Skip to the end of the data.
 569                  */
 570                 p += length;
 571                 total += length;
 572
 573                 /*
 574                  *      Align the data to a multiple of 4 bytes.
 575                  */
 576                 if ((total & 0x03) != 0) {
 577                         size_t i;
 578
 579                         length = 4 - (total & 0x03);
 580                         for (i = 0; i < length; i++) {
 581                                 *p = '\0';
 582                                 p++;
 583                                 total++;
 584                         }
 585                 }
 586         } /* loop over the VP's to write. */
 587
 588         /*
 589          *      Write the data in the buffer to the SSL session.
 590          */
 591         if (total > 0) {
 592 #ifndef NDEBUG
 593                 size_t i;
 594
 595                 if ((debug_flag > 2) && fr_log_fp) {
 596                         for (i = 0; i < total; i++) {
 597                                 if ((i & 0x0f) == 0) fprintf(fr_log_fp, "  TTLS tunnel data out %04x: ", i);
 598
 599                                 fprintf(fr_log_fp, "%02x ", buffer[i]);
 600
 601                                 if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
 602                         }
 603                         if ((total & 0x0f) != 0) fprintf(fr_log_fp, "\n");
 604                 }
 605 #endif
 606
 607                 (tls_session->record_plus)(&tls_session->clean_in, buffer, total);
 608
 609                 /*
 610                  *      FIXME: Check the return code.
 611                  */
 612                 tls_handshake_send(tls_session);
 613         }
 614
 615         /*
 616          *      Everything's OK.
 617          */
 618         return 1;
 619 }
 620
 621 /*
 622  *      Use a reply packet to determine what to do.
 623  */
 624 static int process_reply(EAP_HANDLER *handler, tls_session_t *tls_session,
 625                          REQUEST *request, RADIUS_PACKET *reply)
 626 {
 627         int rcode = RLM_MODULE_REJECT;
 628         VALUE_PAIR *vp;
 629         ttls_tunnel_t *t = tls_session->opaque;
 630
 631         handler = handler;      /* -Wunused */
 632
 633         /*
 634          *      If the response packet was Access-Accept, then
 635          *      we're OK.  If not, die horribly.
 636          *
 637          *      FIXME: Take MS-CHAP2-Success attribute, and
 638          *      tunnel it back to the client, to authenticate
 639          *      ourselves to the client.
 640          *
 641          *      FIXME: If we have an Access-Challenge, then
 642          *      the Reply-Message is tunneled back to the client.
 643          *
 644          *      FIXME: If we have an EAP-Message, then that message
 645          *      must be tunneled back to the client.
 646          *
 647          *      FIXME: If we have an Access-Challenge with a State
 648          *      attribute, then do we tunnel that to the client, or
 649          *      keep track of it ourselves?
 650          *
 651          *      FIXME: EAP-Messages can only start with 'identity',
 652          *      NOT 'eap start', so we should check for that....
 653          */
 654         switch (reply->code) {
 655         case PW_AUTHENTICATION_ACK:
 656                 RDEBUG("Got tunneled Access-Accept");
 657
 658                 rcode = RLM_MODULE_OK;
 659
 660                 /*
 661                  *      MS-CHAP2-Success means that we do NOT return
 662                  *      an Access-Accept, but instead tunnel that
 663                  *      attribute to the client, and keep going with
 664                  *      the TTLS session.  Once the client accepts
 665                  *      our identity, it will respond with an empty
 666                  *      packet, and we will send EAP-Success.
 667                  */
 668                 vp = NULL;
 669                 pairmove2(&vp, &reply->vps, PW_MSCHAP2_SUCCESS);
 670                 if (vp) {
 671                         RDEBUG("Got MS-CHAP2-Success, tunneling it to the client in a challenge.");
 672                         rcode = RLM_MODULE_HANDLED;
 673                         t->authenticated = TRUE;
 674
 675                         /*
 676                          *      Delete MPPE keys & encryption policy.  We don't
 677                          *      want these here.
 678                          */
 679                         pairdelete(&reply->vps, ((311 << 16) | 7));
 680                         pairdelete(&reply->vps, ((311 << 16) | 8));
 681                         pairdelete(&reply->vps, ((311 << 16) | 16));
 682                         pairdelete(&reply->vps, ((311 << 16) | 17));
 683
 684                         /*
 685                          *      Use the tunneled reply, but not now.
 686                          */
 687                         if (t->use_tunneled_reply) {
 688                                 t->reply = reply->vps;
 689                                 reply->vps = NULL;
 690                         }
 691
 692                 } else { /* no MS-CHAP2-Success */
 693                         /*
 694                          *      Can only have EAP-Message if there's
 695                          *      no MS-CHAP2-Success.  (FIXME: EAP-MSCHAP?)
 696                          *
 697                          *      We also do NOT tunnel the EAP-Success
 698                          *      attribute back to the client, as the client
 699                          *      can figure it out, from the non-tunneled
 700                          *      EAP-Success packet.
 701                          */
 702                         pairmove2(&vp, &reply->vps, PW_EAP_MESSAGE);
 703                         pairfree(&vp);
 704                 }
 705
 706                 /*
 707                  *      Handle the ACK, by tunneling any necessary reply
 708                  *      VP's back to the client.
 709                  */
 710                 if (vp) {
 711                         vp2diameter(request, tls_session, vp);
 712                         pairfree(&vp);
 713                 }
 714
 715                 /*
 716                  *      If we've been told to use the attributes from
 717                  *      the reply, then do so.
 718                  *
 719                  *      WARNING: This may leak information about the
 720                  *      tunneled user!
 721                  */
 722                 if (t->use_tunneled_reply) {
 723                         pairdelete(&reply->vps, PW_PROXY_STATE);
 724                         pairadd(&request->reply->vps, reply->vps);
 725                         reply->vps = NULL;
 726                 }
 727                 break;
 728
 729
 730         case PW_AUTHENTICATION_REJECT:
 731                 RDEBUG("Got tunneled Access-Reject");
 732                 rcode = RLM_MODULE_REJECT;
 733                 break;
 734
 735                 /*
 736                  *      Handle Access-Challenge, but only if we
 737                  *      send tunneled reply data.  This is because
 738                  *      an Access-Challenge means that we MUST tunnel
 739                  *      a Reply-Message to the client.
 740                  */
 741         case PW_ACCESS_CHALLENGE:
 742                 RDEBUG("Got tunneled Access-Challenge");
 743
 744                 /*
 745                  *      Keep the State attribute, if necessary.
 746                  *
 747                  *      Get rid of the old State, too.
 748                  */
 749                 pairfree(&t->state);
 750                 pairmove2(&t->state, &reply->vps, PW_STATE);
 751
 752                 /*
 753                  *      We should really be a bit smarter about this,
 754                  *      and move over only those attributes which
 755                  *      are relevant to the authentication request,
 756                  *      but that's a lot more work, and this "dumb"
 757                  *      method works in 99.9% of the situations.
 758                  */
 759                 vp = NULL;
 760                 pairmove2(&vp, &reply->vps, PW_EAP_MESSAGE);
 761
 762                 /*
 763                  *      There MUST be a Reply-Message in the challenge,
 764                  *      which we tunnel back to the client.
 765                  *
 766                  *      If there isn't one in the reply VP's, then
 767                  *      we MUST create one, with an empty string as
 768                  *      it's value.
 769                  */
 770                 pairmove2(&vp, &reply->vps, PW_REPLY_MESSAGE);
 771
 772                 /*
 773                  *      Handle the ACK, by tunneling any necessary reply
 774                  *      VP's back to the client.
 775                  */
 776                 if (vp) {
 777                         vp2diameter(request, tls_session, vp);
 778                         pairfree(&vp);
 779                 }
 780                 rcode = RLM_MODULE_HANDLED;
 781                 break;
 782
 783         default:
 784                 RDEBUG("Unknown RADIUS packet type %d: rejecting tunneled user", reply->code);
 785                 rcode = RLM_MODULE_INVALID;
 786                 break;
 787         }
 788
 789         return rcode;
 790 }
 791
 792
 793 /*
 794  *      Do post-proxy processing,
 795  */
 796 static int eapttls_postproxy(EAP_HANDLER *handler, void *data)
 797 {
 798         int rcode;
 799         tls_session_t *tls_session = (tls_session_t *) data;
 800         REQUEST *fake, *request = handler->request;
 801
 802         RDEBUG("Passing reply from proxy back into the tunnel.");
 803
 804         /*
 805          *      If there was a fake request associated with the proxied
 806          *      request, do more processing of it.
 807          */
 808         fake = (REQUEST *) request_data_get(handler->request,
 809                                             handler->request->proxy,
 810                                             REQUEST_DATA_EAP_MSCHAP_TUNNEL_CALLBACK);
 811
 812         /*
 813          *      Do the callback, if it exists, and if it was a success.
 814          */
 815         if (fake && (handler->request->proxy_reply->code == PW_AUTHENTICATION_ACK)) {
 816                 /*
 817                  *      Terrible hacks.
 818                  */
 819                 rad_assert(fake->packet == NULL);
 820                 fake->packet = request->proxy;
 821                 fake->packet->src_ipaddr = request->packet->src_ipaddr;
 822                 request->proxy = NULL;
 823
 824                 rad_assert(fake->reply == NULL);
 825                 fake->reply = request->proxy_reply;
 826                 request->proxy_reply = NULL;
 827
 828                 if ((debug_flag > 0) && fr_log_fp) {
 829                         fprintf(fr_log_fp, "server %s {\n",
 830                                 (fake->server == NULL) ? "" : fake->server);
 831                 }
 832
 833                 /*
 834                  *      Perform a post-auth stage for the tunneled
 835                  *      session.
 836                  */
 837                 fake->options &= ~RAD_REQUEST_OPTION_PROXY_EAP;
 838                 rcode = rad_postauth(fake);
 839                 RDEBUG2("post-auth returns %d", rcode);
 840
 841                 if ((debug_flag > 0) && fr_log_fp) {
 842                         fprintf(fr_log_fp, "} # server %s\n",
 843                                 (fake->server == NULL) ? "" : fake->server);
 844
 845                         RDEBUG("Final reply from tunneled session code %d",
 846                                fake->reply->code);
 847                         debug_pair_list(fake->reply->vps);
 848                 }
 849
 850                 /*
 851                  *      Terrible hacks.
 852                  */
 853                 request->proxy = fake->packet;
 854                 fake->packet = NULL;
 855                 request->proxy_reply = fake->reply;
 856                 fake->reply = NULL;
 857
 858                 /*
 859                  *      And we're done with this request.
 860                  */
 861
 862                 switch (rcode) {
 863                 case RLM_MODULE_FAIL:
 864                         request_free(&fake);
 865                         eaptls_fail(handler, 0);
 866                         return 0;
 867                         break;
 868
 869                 default:  /* Don't Do Anything */
 870                         RDEBUG2("sGot reply %d",
 871                                request->proxy_reply->code);
 872                         break;
 873                 }
 874         }
 875         request_free(&fake);    /* robust if fake == NULL */
 876
 877         /*
 878          *      Process the reply from the home server.
 879          */
 880         rcode = process_reply(handler, tls_session, handler->request,
 881                               handler->request->proxy_reply);
 882
 883         /*
 884          *      The proxy code uses the reply from the home server as
 885          *      the basis for the reply to the NAS.  We don't want that,
 886          *      so we toss it, after we've had our way with it.
 887          */
 888         pairfree(&handler->request->proxy_reply->vps);
 889
 890         switch (rcode) {
 891         case RLM_MODULE_REJECT:
 892                 RDEBUG("Reply was rejected");
 893                 break;
 894
 895         case RLM_MODULE_HANDLED:
 896                 RDEBUG("Reply was handled");
 897                 eaptls_request(handler->eap_ds, tls_session);
 898                 return 1;
 899
 900         case RLM_MODULE_OK:
 901                 RDEBUG("Reply was OK");
 902
 903                 /*
 904                  *      Success: Automatically return MPPE keys.
 905                  */
 906                 return eaptls_success(handler, 0);
 907
 908         default:
 909                 RDEBUG("Reply was unknown.");
 910                 break;
 911         }
 912
 913         eaptls_fail(handler, 0);
 914         return 0;
 915 }
 916
 917
 918 /*
 919  *      Free a request.
 920  */
 921 static void my_request_free(void *data)
 922 {
 923         REQUEST *request = (REQUEST *)data;
 924
 925         request_free(&request);
 926 }
 927
 928
 929 /*
 930  *      Process the "diameter" contents of the tunneled data.
 931  */
 932 int eapttls_process(EAP_HANDLER *handler, tls_session_t *tls_session)
 933 {
 934         int rcode = PW_AUTHENTICATION_REJECT;
 935         REQUEST *fake;
 936         VALUE_PAIR *vp;
 937         ttls_tunnel_t *t;
 938         const uint8_t *data;
 939         size_t data_len;
 940         REQUEST *request = handler->request;
 941
 942         /*
 943          *      Just look at the buffer directly, without doing
 944          *      record_minus.
 945          */
 946         data_len = tls_session->clean_out.used;
 947         tls_session->clean_out.used = 0;
 948         data = tls_session->clean_out.data;
 949
 950         t = (ttls_tunnel_t *) tls_session->opaque;
 951
 952         /*
 953          *      If there's no data, maybe this is an ACK to an
 954          *      MS-CHAP2-Success.
 955          */
 956         if (data_len == 0) {
 957                 if (t->authenticated) {
 958                         RDEBUG("Got ACK, and the user was already authenticated.");
 959                         return PW_AUTHENTICATION_ACK;
 960                 } /* else no session, no data, die. */
 961
 962                 /*
 963                  *      FIXME: Call SSL_get_error() to see what went
 964                  *      wrong.
 965                  */
 966                 RDEBUG2("SSL_read Error");
 967                 return PW_AUTHENTICATION_REJECT;
 968         }
 969
 970 #ifndef NDEBUG
 971         if ((debug_flag > 2) && fr_log_fp) {
 972                 size_t i;
 973
 974                 for (i = 0; i < data_len; i++) {
 975                         if ((i & 0x0f) == 0) fprintf(fr_log_fp, "  TTLS tunnel data in %04x: ", i);
 976
 977                         fprintf(fr_log_fp, "%02x ", data[i]);
 978
 979                         if ((i & 0x0f) == 0x0f) fprintf(fr_log_fp, "\n");
 980                 }
 981                 if ((data_len & 0x0f) != 0) fprintf(fr_log_fp, "\n");
 982         }
 983 #endif
 984
 985         if (!diameter_verify(request, data, data_len)) {
 986                 return PW_AUTHENTICATION_REJECT;
 987         }
 988
 989         /*
 990          *      Allocate a fake REQUEST structe.
 991          */
 992         fake = request_alloc_fake(request);
 993
 994         rad_assert(fake->packet->vps == NULL);
 995
 996         /*
 997          *      Add the tunneled attributes to the fake request.
 998          */
 999         fake->packet->vps = diameter2vp(request, tls_session->ssl, data, data_len);
1000         if (!fake->packet->vps) {
1001                 request_free(&fake);
1002                 return PW_AUTHENTICATION_REJECT;
1003         }
1004
1005         /*
1006          *      Tell the request that it's a fake one.
1007          */
1008         vp = pairmake("Freeradius-Proxied-To", "127.0.0.1", T_OP_EQ);
1009         if (vp) {
1010                 pairadd(&fake->packet->vps, vp);
1011         }
1012
1013         if ((debug_flag > 0) && fr_log_fp) {
1014                 RDEBUG("Got tunneled request");
1015
1016                 debug_pair_list(fake->packet->vps);
1017         }
1018
1019         /*
1020          *      Update other items in the REQUEST data structure.
1021          */
1022         fake->username = pairfind(fake->packet->vps, PW_USER_NAME);
1023         fake->password = pairfind(fake->packet->vps, PW_USER_PASSWORD);
1024
1025         /*
1026          *      No User-Name, try to create one from stored data.
1027          */
1028         if (!fake->username) {
1029                 /*
1030                  *      No User-Name in the stored data, look for
1031                  *      an EAP-Identity, and pull it out of there.
1032                  */
1033                 if (!t->username) {
1034                         vp = pairfind(fake->packet->vps, PW_EAP_MESSAGE);
1035                         if (vp &&
1036                             (vp->length >= EAP_HEADER_LEN + 2) &&
1037                             (vp->vp_strvalue[0] == PW_EAP_RESPONSE) &&
1038                             (vp->vp_strvalue[EAP_HEADER_LEN] == PW_EAP_IDENTITY) &&
1039                             (vp->vp_strvalue[EAP_HEADER_LEN + 1] != 0)) {
1040                                 /*
1041                                  *      Create & remember a User-Name
1042                                  */
1043                                 t->username = pairmake("User-Name", "", T_OP_EQ);
1044                                 rad_assert(t->username != NULL);
1045
1046                                 memcpy(t->username->vp_strvalue, vp->vp_strvalue + 5,
1047                                        vp->length - 5);
1048                                 t->username->length = vp->length - 5;
1049                                 t->username->vp_strvalue[t->username->length] = 0;
1050
1051                                 RDEBUG("Got tunneled identity of %s",
1052                                        t->username->vp_strvalue);
1053
1054                                 /*
1055                                  *      If there's a default EAP type,
1056                                  *      set it here.
1057                                  */
1058                                 if (t->default_eap_type != 0) {
1059                                         RDEBUG("Setting default EAP type for tunneled EAP session.");
1060                                         vp = paircreate(PW_EAP_TYPE,
1061                                                         PW_TYPE_INTEGER);
1062                                         rad_assert(vp != NULL);
1063                                         vp->vp_integer = t->default_eap_type;
1064                                         pairadd(&fake->config_items, vp);
1065                                 }
1066
1067                         } else {
1068                                 /*
1069                                  *      Don't reject the request outright,
1070                                  *      as it's permitted to do EAP without
1071                                  *      user-name.
1072                                  */
1073                                 RDEBUG2("WARNING! No EAP-Identity found to start EAP conversation.");
1074                         }
1075                 } /* else there WAS a t->username */
1076
1077                 if (t->username) {
1078                         vp = paircopy(t->username);
1079                         pairadd(&fake->packet->vps, vp);
1080                         fake->username = pairfind(fake->packet->vps, PW_USER_NAME);
1081                 }
1082         } /* else the request ALREADY had a User-Name */
1083
1084         /*
1085          *      Add the State attribute, too, if it exists.
1086          */
1087         if (t->state) {
1088                 vp = paircopy(t->state);
1089                 if (vp) pairadd(&fake->packet->vps, vp);
1090         }
1091
1092         /*
1093          *      If this is set, we copy SOME of the request attributes
1094          *      from outside of the tunnel to inside of the tunnel.
1095          *
1096          *      We copy ONLY those attributes which do NOT already
1097          *      exist in the tunneled request.
1098          */
1099         if (t->copy_request_to_tunnel) {
1100                 VALUE_PAIR *copy;
1101
1102                 for (vp = request->packet->vps; vp != NULL; vp = vp->next) {
1103                         /*
1104                          *      The attribute is a server-side thingy,
1105                          *      don't copy it.
1106                          */
1107                         if ((vp->attribute > 255) &&
1108                             (((vp->attribute >> 16) & 0xffff) == 0)) {
1109                                 continue;
1110                         }
1111
1112                         /*
1113                          *      The outside attribute is already in the
1114                          *      tunnel, don't copy it.
1115                          *
1116                          *      This works for BOTH attributes which
1117                          *      are originally in the tunneled request,
1118                          *      AND attributes which are copied there
1119                          *      from below.
1120                          */
1121                         if (pairfind(fake->packet->vps, vp->attribute)) {
1122                                 continue;
1123                         }
1124
1125                         /*
1126                          *      Some attributes are handled specially.
1127                          */
1128                         switch (vp->attribute) {
1129                                 /*
1130                                  *      NEVER copy Message-Authenticator,
1131                                  *      EAP-Message, or State.  They're
1132                                  *      only for outside of the tunnel.
1133                                  */
1134                         case PW_USER_NAME:
1135                         case PW_USER_PASSWORD:
1136                         case PW_CHAP_PASSWORD:
1137                         case PW_CHAP_CHALLENGE:
1138                         case PW_PROXY_STATE:
1139                         case PW_MESSAGE_AUTHENTICATOR:
1140                         case PW_EAP_MESSAGE:
1141                         case PW_STATE:
1142                                 continue;
1143                                 break;
1144
1145                                 /*
1146                                  *      By default, copy it over.
1147                                  */
1148                         default:
1149                                 break;
1150                         }
1151
1152                         /*
1153                          *      Don't copy from the head, we've already
1154                          *      checked it.
1155                          */
1156                         copy = paircopy2(vp, vp->attribute);
1157                         pairadd(&fake->packet->vps, copy);
1158                 }
1159         }
1160
1161         if ((vp = pairfind(request->config_items, PW_VIRTUAL_SERVER)) != NULL) {
1162                 fake->server = vp->vp_strvalue;
1163
1164         } else if (t->virtual_server) {
1165                 fake->server = t->virtual_server;
1166
1167         } /* else fake->server == request->server */
1168
1169
1170         if ((debug_flag > 0) && fr_log_fp) {
1171                 RDEBUG("Sending tunneled request");
1172
1173                 debug_pair_list(fake->packet->vps);
1174
1175                 fprintf(fr_log_fp, "server %s {\n",
1176                         (fake->server == NULL) ? "" : fake->server);
1177         }
1178
1179         /*
1180          *      Call authentication recursively, which will
1181          *      do PAP, CHAP, MS-CHAP, etc.
1182          */
1183         rad_authenticate(fake);
1184
1185         /*
1186          *      Note that we don't do *anything* with the reply
1187          *      attributes.
1188          */
1189         if ((debug_flag > 0) && fr_log_fp) {
1190                 fprintf(fr_log_fp, "} # server %s\n",
1191                         (fake->server == NULL) ? "" : fake->server);
1192
1193                 RDEBUG("Got tunneled reply code %d", fake->reply->code);
1194
1195                 debug_pair_list(fake->reply->vps);
1196         }
1197
1198         /*
1199          *      Decide what to do with the reply.
1200          */
1201         switch (fake->reply->code) {
1202         case 0:                 /* No reply code, must be proxied... */
1203                 vp = pairfind(fake->config_items, PW_PROXY_TO_REALM);
1204                 if (vp) {
1205                         eap_tunnel_data_t *tunnel;
1206                         RDEBUG("Tunneled authentication will be proxied to %s", vp->vp_strvalue);
1207
1208                         /*
1209                          *      Tell the original request that it's going
1210                          *      to be proxied.
1211                          */
1212                         pairmove2(&(request->config_items),
1213                                   &(fake->config_items),
1214                                   PW_PROXY_TO_REALM);
1215
1216                         /*
1217                          *      Seed the proxy packet with the
1218                          *      tunneled request.
1219                          */
1220                         rad_assert(request->proxy == NULL);
1221                         request->proxy = fake->packet;
1222                         fake->packet = NULL;
1223                         rad_free(&fake->reply);
1224                         fake->reply = NULL;
1225
1226                         /*
1227                          *      Set up the callbacks for the tunnel
1228                          */
1229                         tunnel = rad_malloc(sizeof(*tunnel));
1230                         memset(tunnel, 0, sizeof(*tunnel));
1231
1232                         tunnel->tls_session = tls_session;
1233                         tunnel->callback = eapttls_postproxy;
1234
1235                         /*
1236                          *      Associate the callback with the request.
1237                          */
1238                         rcode = request_data_add(request,
1239                                                  request->proxy,
1240                                                  REQUEST_DATA_EAP_TUNNEL_CALLBACK,
1241                                                  tunnel, free);
1242                         rad_assert(rcode == 0);
1243
1244                         /*
1245                          *      rlm_eap.c has taken care of associating
1246                          *      the handler with the fake request.
1247                          *
1248                          *      So we associate the fake request with
1249                          *      this request.
1250                          */
1251                         rcode = request_data_add(request,
1252                                                  request->proxy,
1253                                                  REQUEST_DATA_EAP_MSCHAP_TUNNEL_CALLBACK,
1254                                                  fake, my_request_free);
1255                         rad_assert(rcode == 0);
1256                         fake = NULL;
1257
1258                         /*
1259                          *      Didn't authenticate the packet, but
1260                          *      we're proxying it.
1261                          */
1262                         rcode = PW_STATUS_CLIENT;
1263
1264                 } else {
1265                         RDEBUG("No tunneled reply was found for request %d , and the request was not proxied: rejecting the user.",
1266                                request->number);
1267                         rcode = PW_AUTHENTICATION_REJECT;
1268                 }
1269                 break;
1270
1271         default:
1272                 /*
1273                  *      Returns RLM_MODULE_FOO, and we want to return
1274                  *      PW_FOO
1275                  */
1276                 rcode = process_reply(handler, tls_session, request,
1277                                       fake->reply);
1278                 switch (rcode) {
1279                 case RLM_MODULE_REJECT:
1280                         rcode = PW_AUTHENTICATION_REJECT;
1281                         break;
1282
1283                 case RLM_MODULE_HANDLED:
1284                         rcode = PW_ACCESS_CHALLENGE;
1285                         break;
1286
1287                 case RLM_MODULE_OK:
1288                         rcode = PW_AUTHENTICATION_ACK;
1289                         break;
1290
1291                 default:
1292                         rcode = PW_AUTHENTICATION_REJECT;
1293                         break;
1294                 }
1295                 break;
1296         }
1297
1298         request_free(&fake);
1299
1300         return rcode;
1301 }