mech_eap/accept_sec_context.c

   1 /*
   2  * Copyright (c) 2011, 2013, 2015, JANET(UK)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. Neither the name of JANET(UK) nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 /*
  34  * Establish a security context on the acceptor (server). These functions
  35  * wrap around libradsec and (thus) talk to a RADIUS server or proxy.
  36  */
  37
  38 #include "gssapiP_eap.h"
  39
  40 #ifdef GSSEAP_ENABLE_REAUTH
  41 static OM_uint32
  42 eapGssSmAcceptGssReauth(OM_uint32 *minor,
  43                         gss_cred_id_t cred,
  44                         gss_ctx_id_t ctx,
  45                         gss_const_name_t target,
  46                         gss_OID mech,
  47                         OM_uint32 reqFlags,
  48                         OM_uint32 timeReq,
  49                         gss_channel_bindings_t chanBindings,
  50                         gss_buffer_t inputToken,
  51                         gss_buffer_t outputToken,
  52                         OM_uint32 *smFlags);
  53 #endif
  54
  55 /*
  56  * Mark an acceptor context as ready for cryptographic operations
  57  */
  58 static OM_uint32
  59 acceptReadyEap(OM_uint32 *minor, gss_ctx_id_t ctx, gss_cred_id_t cred)
  60 {
  61     OM_uint32 major, tmpMinor;
  62     rs_const_avp *vp;
  63     gss_buffer_desc nameBuf = GSS_C_EMPTY_BUFFER;
  64
  65     /* Cache encryption type derived from selected mechanism OID */
  66     major = gssEapOidToEnctype(minor, ctx->mechanismUsed,
  67                                &ctx->encryptionType);
  68     if (GSS_ERROR(major))
  69         return major;
  70
  71     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
  72
  73     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  74                                   PW_USER_NAME, 0, &vp);
  75     if (major == GSS_S_COMPLETE && rs_avp_length(vp) != 0) {
  76         rs_avp_octets_value_byref((rs_avp *)vp,
  77                                   (unsigned char **)&nameBuf.value,
  78                                   &nameBuf.length);
  79     } else {
  80         ctx->gssFlags |= GSS_C_ANON_FLAG;
  81     }
  82
  83     major = gssEapImportName(minor, &nameBuf,
  84                              (ctx->gssFlags & GSS_C_ANON_FLAG) ?
  85                                 GSS_C_NT_ANONYMOUS : GSS_C_NT_USER_NAME,
  86                              ctx->mechanismUsed,
  87                              &ctx->initiatorName);
  88     if (GSS_ERROR(major))
  89         return major;
  90
  91     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  92                                   PW_MS_MPPE_SEND_KEY, VENDORPEC_MICROSOFT, &vp);
  93     if (GSS_ERROR(major)) {
  94         *minor = GSSEAP_KEY_UNAVAILABLE;
  95         return GSS_S_UNAVAILABLE;
  96     }
  97
  98     major = gssEapDeriveRfc3961Key(minor,
  99                                    rs_avp_octets_value_const_ptr(vp),
 100                                    rs_avp_length(vp),
 101                                    ctx->encryptionType,
 102                                    &ctx->rfc3961Key);
 103     if (GSS_ERROR(major))
 104         return major;
 105
 106     major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 107                                        &ctx->checksumType);
 108     if (GSS_ERROR(major))
 109         return major;
 110
 111     major = sequenceInit(minor,
 112                          &ctx->seqState, ctx->recvSeq,
 113                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 114                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 115                          TRUE);
 116     if (GSS_ERROR(major))
 117         return major;
 118
 119     major = gssEapCreateAttrContext(minor, cred, ctx,
 120                                     &ctx->initiatorName->attrCtx,
 121                                     &ctx->expiryTime);
 122     if (GSS_ERROR(major))
 123         return major;
 124
 125     if (ctx->expiryTime != 0 && ctx->expiryTime < time(NULL)) {
 126         *minor = GSSEAP_CRED_EXPIRED;
 127         return GSS_S_CREDENTIALS_EXPIRED;
 128     }
 129
 130     *minor = 0;
 131     return GSS_S_COMPLETE;
 132 }
 133
 134 static OM_uint32
 135 eapGssSmAcceptAcceptorName(OM_uint32 *minor,
 136                            gss_cred_id_t cred GSSEAP_UNUSED,
 137                            gss_ctx_id_t ctx,
 138                            gss_const_name_t target GSSEAP_UNUSED,
 139                            gss_OID mech GSSEAP_UNUSED,
 140                            OM_uint32 reqFlags GSSEAP_UNUSED,
 141                            OM_uint32 timeReq GSSEAP_UNUSED,
 142                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 143                            gss_buffer_t inputToken GSSEAP_UNUSED,
 144                            gss_buffer_t outputToken,
 145                            OM_uint32 *smFlags GSSEAP_UNUSED)
 146 {
 147     OM_uint32 major;
 148
 149     /* XXX TODO import and validate name from inputToken */
 150
 151     if (ctx->acceptorName != GSS_C_NO_NAME) {
 152         /* Send desired target name to acceptor */
 153         major = gssEapDisplayName(minor, ctx->acceptorName,
 154                                   outputToken, NULL);
 155         if (GSS_ERROR(major))
 156             return major;
 157     }
 158
 159     return GSS_S_CONTINUE_NEEDED;
 160 }
 161
 162 #ifdef GSSEAP_DEBUG
 163 static OM_uint32
 164 eapGssSmAcceptVendorInfo(OM_uint32 *minor,
 165                          gss_cred_id_t cred GSSEAP_UNUSED,
 166                          gss_ctx_id_t ctx GSSEAP_UNUSED,
 167                          gss_const_name_t target GSSEAP_UNUSED,
 168                          gss_OID mech GSSEAP_UNUSED,
 169                          OM_uint32 reqFlags GSSEAP_UNUSED,
 170                          OM_uint32 timeReq GSSEAP_UNUSED,
 171                          gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 172                          gss_buffer_t inputToken,
 173                          gss_buffer_t outputToken GSSEAP_UNUSED,
 174                          OM_uint32 *smFlags GSSEAP_UNUSED)
 175 {
 176     fprintf(stderr, "GSS-EAP: vendor: %.*s\n",
 177             (int)inputToken->length, (char *)inputToken->value);
 178
 179     *minor = 0;
 180     return GSS_S_CONTINUE_NEEDED;
 181 }
 182 #endif
 183
 184
 185 /*
 186  * Emit a identity EAP request to force the initiator (peer) to identify
 187  * itself.
 188  */
 189 static OM_uint32
 190 eapGssSmAcceptIdentity(OM_uint32 *minor,
 191                        gss_cred_id_t cred,
 192                        gss_ctx_id_t ctx,
 193                        gss_const_name_t target GSSEAP_UNUSED,
 194                        gss_OID mech GSSEAP_UNUSED,
 195                        OM_uint32 reqFlags GSSEAP_UNUSED,
 196                        OM_uint32 timeReq GSSEAP_UNUSED,
 197                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 198                        gss_buffer_t inputToken,
 199                        gss_buffer_t outputToken,
 200                        OM_uint32 *smFlags)
 201 {
 202     OM_uint32 major;
 203     struct wpabuf *reqData;
 204     gss_buffer_desc pktBuffer;
 205
 206     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 207         *minor = GSSEAP_CRED_MECH_MISMATCH;
 208         return GSS_S_BAD_MECH;
 209     }
 210
 211     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
 212         *minor = GSSEAP_WRONG_SIZE;
 213         return GSS_S_DEFECTIVE_TOKEN;
 214     }
 215
 216     reqData = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY, 0,
 217                             EAP_CODE_REQUEST, 0);
 218     if (reqData == NULL) {
 219         *minor = ENOMEM;
 220         return GSS_S_FAILURE;
 221     }
 222
 223     pktBuffer.length = wpabuf_len(reqData);
 224     pktBuffer.value = (void *)wpabuf_head(reqData);
 225
 226     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 227     if (GSS_ERROR(major))
 228         return major;
 229
 230     wpabuf_free(reqData);
 231
 232     GSSEAP_SM_TRANSITION_NEXT(ctx);
 233
 234     *minor = 0;
 235     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 236
 237     return GSS_S_CONTINUE_NEEDED;
 238 }
 239
 240 /*
 241  * Returns TRUE if the input token contains an EAP identity response.
 242  */
 243 static int
 244 isIdentityResponseP(gss_buffer_t inputToken)
 245 {
 246     struct wpabuf respData;
 247
 248     wpabuf_set(&respData, inputToken->value, inputToken->length);
 249
 250     return (eap_get_type(&respData) == EAP_TYPE_IDENTITY);
 251 }
 252
 253 /*
 254  * Save the asserted initiator identity from the EAP identity response.
 255  */
 256 static OM_uint32
 257 importInitiatorIdentity(OM_uint32 *minor,
 258                         gss_ctx_id_t ctx,
 259                         gss_buffer_t inputToken)
 260 {
 261     OM_uint32 tmpMinor;
 262     struct wpabuf respData;
 263     const unsigned char *pos;
 264     size_t len;
 265     gss_buffer_desc nameBuf;
 266
 267     wpabuf_set(&respData, inputToken->value, inputToken->length);
 268
 269     pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY,
 270                            &respData, &len);
 271     if (pos == NULL) {
 272         *minor = GSSEAP_PEER_BAD_MESSAGE;
 273         return GSS_S_DEFECTIVE_TOKEN;
 274     }
 275
 276     nameBuf.value = (void *)pos;
 277     nameBuf.length = len;
 278
 279     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
 280
 281     return gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
 282                             ctx->mechanismUsed, &ctx->initiatorName);
 283 }
 284
 285 /*
 286  * Pass the asserted initiator identity to the authentication server.
 287  */
 288 static OM_uint32
 289 setInitiatorIdentity(OM_uint32 *minor,
 290                      gss_ctx_id_t ctx,
 291                      struct rs_packet *req)
 292 {
 293     OM_uint32 major, tmpMinor;
 294     gss_buffer_desc nameBuf;
 295
 296     /*
 297      * We should have got an EAP identity response, but if we didn't, then
 298      * we will just avoid sending User-Name. Note that radsecproxy requires
 299      * User-Name to be sent on every request (presumably so it can remain
 300      * stateless).
 301      */
 302     if (ctx->initiatorName != GSS_C_NO_NAME) {
 303         major = gssEapDisplayName(minor, ctx->initiatorName, &nameBuf, NULL);
 304         if (GSS_ERROR(major))
 305             return major;
 306
 307         major = gssEapRadiusAddAvp(minor, req, PW_USER_NAME, 0, &nameBuf);
 308         if (GSS_ERROR(major))
 309             return major;
 310
 311         gss_release_buffer(&tmpMinor, &nameBuf);
 312     }
 313
 314     *minor = 0;
 315     return GSS_S_COMPLETE;
 316 }
 317
 318 /*
 319  * Pass the asserted acceptor identity to the authentication server.
 320  */
 321 static OM_uint32
 322 setAcceptorIdentity(OM_uint32 *minor,
 323                     gss_ctx_id_t ctx,
 324                     struct rs_packet *req)
 325 {
 326     OM_uint32 major;
 327     gss_buffer_desc nameBuf;
 328     krb5_context krbContext = NULL;
 329     krb5_principal krbPrinc;
 330     struct rs_context *rc = ctx->acceptorCtx.radContext;
 331
 332     GSSEAP_ASSERT(rc != NULL);
 333
 334     if (ctx->acceptorName == GSS_C_NO_NAME) {
 335         *minor = 0;
 336         return GSS_S_COMPLETE;
 337     }
 338
 339     if ((ctx->acceptorName->flags & NAME_FLAG_SERVICE) == 0) {
 340         *minor = GSSEAP_BAD_SERVICE_NAME;
 341         return GSS_S_BAD_NAME;
 342     }
 343
 344     GSSEAP_KRB_INIT(&krbContext);
 345
 346     krbPrinc = ctx->acceptorName->krbPrincipal;
 347     GSSEAP_ASSERT(krbPrinc != NULL);
 348     GSSEAP_ASSERT(KRB_PRINC_LENGTH(krbPrinc) >= 1);
 349
 350     /* Acceptor-Service-Name */
 351     krbPrincComponentToGssBuffer(krbPrinc, 0, &nameBuf);
 352
 353     major = gssEapRadiusAddAvp(minor, req,
 354                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 355                                0,
 356                                &nameBuf);
 357     if (GSS_ERROR(major))
 358         return major;
 359
 360     /* Acceptor-Host-Name */
 361     if (KRB_PRINC_LENGTH(krbPrinc) >= 2) {
 362         krbPrincComponentToGssBuffer(krbPrinc, 1, &nameBuf);
 363
 364         major = gssEapRadiusAddAvp(minor, req,
 365                                    PW_GSS_ACCEPTOR_HOST_NAME,
 366                                    0,
 367                                    &nameBuf);
 368         if (GSS_ERROR(major))
 369             return major;
 370     }
 371     if (KRB_PRINC_LENGTH(krbPrinc) > 2) {
 372         /* Acceptor-Service-Specific */
 373         *minor = krbPrincUnparseServiceSpecifics(krbContext,
 374                                                  krbPrinc, &nameBuf);
 375         if (*minor != 0)
 376             return GSS_S_FAILURE;
 377
 378         major = gssEapRadiusAddAvp(minor, req,
 379                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFICS,
 380                                    0,
 381                                    &nameBuf);
 382         krbFreeUnparsedName(krbContext, &nameBuf);
 383         if (GSS_ERROR(major))
 384             return major;
 385     }
 386
 387     krbPrincRealmToGssBuffer(krbPrinc, &nameBuf);
 388     if (nameBuf.length != 0) {
 389         /* Acceptor-Realm-Name */
 390         major = gssEapRadiusAddAvp(minor, req,
 391                                    PW_GSS_ACCEPTOR_REALM_NAME,
 392                                    0,
 393                                    &nameBuf);
 394         if (GSS_ERROR(major))
 395             return major;
 396     }
 397
 398     *minor = 0;
 399     return GSS_S_COMPLETE;
 400 }
 401
 402 /*
 403  * Allocate a RadSec handle
 404  */
 405 static OM_uint32
 406 createRadiusHandle(OM_uint32 *minor,
 407                    gss_cred_id_t cred,
 408                    gss_ctx_id_t ctx)
 409 {
 410     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 411     struct rs_error *err;
 412     const char *configStanza = "gss-eap";
 413     OM_uint32 major;
 414
 415     GSSEAP_ASSERT(actx->radContext == NULL);
 416     GSSEAP_ASSERT(actx->radConn == NULL);
 417     GSSEAP_ASSERT(cred != GSS_C_NO_CREDENTIAL);
 418
 419     major = gssEapCreateRadiusContext(minor, cred, &actx->radContext);
 420     if (GSS_ERROR(major))
 421         return major;
 422
 423     if (cred->radiusConfigStanza.value != NULL)
 424         configStanza = (const char *)cred->radiusConfigStanza.value;
 425
 426     if (rs_conn_create(actx->radContext, &actx->radConn, configStanza) != 0) {
 427         err = rs_err_conn_pop(actx->radConn);
 428         return gssEapRadiusMapError(minor, err);
 429     }
 430
 431     if (actx->radServer != NULL) {
 432         if (rs_conn_select_peer(actx->radConn, actx->radServer) != 0) {
 433             err = rs_err_conn_pop(actx->radConn);
 434             return gssEapRadiusMapError(minor, err);
 435         }
 436     }
 437
 438     *minor = 0;
 439     return GSS_S_COMPLETE;
 440 }
 441
 442 /**
 443  * Choose the correct error for an access reject packet.
 444  */
 445 static OM_uint32
 446 eapGssAcceptHandleReject(OM_uint32 *minor,
 447                          struct rs_packet *response)
 448 {
 449     rs_avp **vps;
 450     rs_const_avp *vp = NULL;
 451     OM_uint32 major;
 452     const char *reply_message = NULL;
 453     size_t reply_length = 0;
 454
 455     rs_packet_avps(response, &vps);
 456     major = gssEapRadiusGetRawAvp(minor, *vps,
 457                                   PW_REPLY_MESSAGE, 0, &vp);
 458     if (!GSS_ERROR(major)) {
 459         reply_message = rs_avp_string_value(vp);
 460         reply_length = rs_avp_length(vp);
 461     }
 462
 463     major = gssEapRadiusGetRawAvp(minor, *vps,
 464                                   PW_ERROR_CAUSE, 0, &vp);
 465     if (!GSS_ERROR(major)) {
 466         switch (rs_avp_integer_value(vp)) {
 467             /* Values from http://www.iana.org/assignments/radius-types/radius-types.xhtml#radius-types-18 */
 468         case 502: /* request not routable (proxy) */
 469             *minor = GSSEAP_RADIUS_UNROUTABLE;
 470             break;
 471         case 501: /* administratively prohibited */
 472             *minor = GSSEAP_RADIUS_ADMIN_PROHIBIT;
 473             break;
 474
 475         default:
 476             *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 477             break;
 478         }
 479     } else
 480         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 481
 482     if (reply_message != NULL)
 483         gssEapSaveStatusInfo(*minor, "%s: %.*s", error_message(*minor),
 484                              reply_length, reply_message);
 485     else
 486         gssEapSaveStatusInfo(*minor, "%s", error_message(*minor));
 487
 488     return GSS_S_DEFECTIVE_CREDENTIAL;
 489 }
 490
 491 /*
 492  * Process a EAP response from the initiator.
 493  */
 494 static OM_uint32
 495 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 496                            gss_cred_id_t cred,
 497                            gss_ctx_id_t ctx,
 498                            gss_const_name_t target GSSEAP_UNUSED,
 499                            gss_OID mech GSSEAP_UNUSED,
 500                            OM_uint32 reqFlags GSSEAP_UNUSED,
 501                            OM_uint32 timeReq GSSEAP_UNUSED,
 502                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 503                            gss_buffer_t inputToken,
 504                            gss_buffer_t outputToken,
 505                            OM_uint32 *smFlags)
 506 {
 507     OM_uint32 major, tmpMinor;
 508     struct rs_connection *rconn;
 509     struct rs_request *request = NULL;
 510     struct rs_packet *req = NULL, *resp = NULL;
 511     int isAccessChallenge;
 512
 513     if (ctx->acceptorCtx.radContext == NULL) {
 514         /* May be NULL from an imported partial context */
 515         major = createRadiusHandle(minor, cred, ctx);
 516         if (GSS_ERROR(major))
 517             goto cleanup;
 518     }
 519
 520     if (isIdentityResponseP(inputToken)) {
 521         major = importInitiatorIdentity(minor, ctx, inputToken);
 522         if (GSS_ERROR(major))
 523             return major;
 524     }
 525
 526     rconn = ctx->acceptorCtx.radConn;
 527
 528     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 529         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 530         goto cleanup;
 531     }
 532
 533     major = setInitiatorIdentity(minor, ctx, req);
 534     if (GSS_ERROR(major))
 535         goto cleanup;
 536
 537     major = setAcceptorIdentity(minor, ctx, req);
 538     if (GSS_ERROR(major))
 539         goto cleanup;
 540
 541     major = gssEapRadiusAddAvp(minor, req,
 542                                PW_EAP_MESSAGE, 0, inputToken);
 543     if (GSS_ERROR(major))
 544         goto cleanup;
 545
 546     if (ctx->acceptorCtx.state.length != 0) {
 547         major = gssEapRadiusAddAvp(minor, req, PW_STATE, 0,
 548                                    &ctx->acceptorCtx.state);
 549         if (GSS_ERROR(major))
 550             goto cleanup;
 551
 552         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 553     }
 554
 555     if (rs_request_create(rconn, &request) != 0) {
 556         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 557         goto cleanup;
 558     }
 559
 560     rs_request_add_reqpkt(request, req);
 561     req = NULL;
 562
 563     if (rs_request_send(request, &resp) != 0) {
 564         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 565         goto cleanup;
 566     }
 567
 568     GSSEAP_ASSERT(resp != NULL);
 569
 570     isAccessChallenge = 0;
 571
 572     switch (rs_packet_code(resp)) {
 573     case PW_ACCESS_CHALLENGE:
 574         isAccessChallenge = 1;
 575         break;
 576     case PW_ACCESS_ACCEPT:
 577         break;
 578     case PW_ACCESS_REJECT:
 579         major = eapGssAcceptHandleReject( minor, resp);
 580         goto cleanup;
 581         break;
 582     default:
 583         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 584         major = GSS_S_FAILURE;
 585         goto cleanup;
 586         break;
 587     }
 588
 589     major = gssEapRadiusGetAvp(minor, resp, PW_EAP_MESSAGE, 0,
 590                                outputToken, TRUE);
 591     if (major == GSS_S_UNAVAILABLE && isAccessChallenge) {
 592         *minor = GSSEAP_MISSING_EAP_REQUEST;
 593         major = GSS_S_DEFECTIVE_TOKEN;
 594         goto cleanup;
 595     } else if (GSS_ERROR(major))
 596         goto cleanup;
 597
 598     if (isAccessChallenge) {
 599         major = gssEapRadiusGetAvp(minor, resp, PW_STATE, 0,
 600                                    &ctx->acceptorCtx.state, TRUE);
 601         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 602             goto cleanup;
 603     } else {
 604         rs_avp **vps;
 605
 606         rs_packet_avps(resp, &vps);
 607
 608         ctx->acceptorCtx.vps = *vps;
 609         *vps = NULL;
 610
 611         major = acceptReadyEap(minor, ctx, cred);
 612         if (GSS_ERROR(major))
 613             goto cleanup;
 614
 615         GSSEAP_SM_TRANSITION_NEXT(ctx);
 616     }
 617
 618     major = GSS_S_CONTINUE_NEEDED;
 619     *minor = 0;
 620     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 621
 622 cleanup:
 623     if (request != NULL)
 624         rs_request_destroy(request);
 625     if (req != NULL)
 626         rs_packet_destroy(req);
 627     if (resp != NULL)
 628         rs_packet_destroy(resp);
 629     if (GSSEAP_SM_STATE(ctx) == GSSEAP_STATE_INITIATOR_EXTS) {
 630         GSSEAP_ASSERT(major == GSS_S_CONTINUE_NEEDED);
 631
 632         rs_conn_destroy(ctx->acceptorCtx.radConn);
 633         ctx->acceptorCtx.radConn = NULL;
 634     }
 635
 636     return major;
 637 }
 638
 639 static OM_uint32
 640 eapGssSmAcceptGssFlags(OM_uint32 *minor,
 641                        gss_cred_id_t cred GSSEAP_UNUSED,
 642                        gss_ctx_id_t ctx,
 643                        gss_const_name_t target GSSEAP_UNUSED,
 644                        gss_OID mech GSSEAP_UNUSED,
 645                        OM_uint32 reqFlags GSSEAP_UNUSED,
 646                        OM_uint32 timeReq GSSEAP_UNUSED,
 647                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 648                        gss_buffer_t inputToken,
 649                        gss_buffer_t outputToken GSSEAP_UNUSED,
 650                        OM_uint32 *smFlags GSSEAP_UNUSED)
 651 {
 652     unsigned char *p;
 653     OM_uint32 initiatorGssFlags;
 654
 655     GSSEAP_ASSERT((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
 656
 657     if (inputToken->length < 4) {
 658         *minor = GSSEAP_TOK_TRUNC;
 659         return GSS_S_DEFECTIVE_TOKEN;
 660     }
 661
 662     /* allow flags to grow for future expansion */
 663     p = (unsigned char *)inputToken->value + inputToken->length - 4;
 664
 665     initiatorGssFlags = load_uint32_be(p);
 666     initiatorGssFlags &= GSSEAP_WIRE_FLAGS_MASK;
 667
 668     ctx->gssFlags |= initiatorGssFlags;
 669
 670     return GSS_S_CONTINUE_NEEDED;
 671 }
 672
 673 static OM_uint32
 674 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 675                                  gss_cred_id_t cred GSSEAP_UNUSED,
 676                                  gss_ctx_id_t ctx,
 677                                  gss_const_name_t target GSSEAP_UNUSED,
 678                                  gss_OID mech GSSEAP_UNUSED,
 679                                  OM_uint32 reqFlags GSSEAP_UNUSED,
 680                                  OM_uint32 timeReq GSSEAP_UNUSED,
 681                                  gss_channel_bindings_t chanBindings,
 682                                  gss_buffer_t inputToken,
 683                                  gss_buffer_t outputToken GSSEAP_UNUSED,
 684                                  OM_uint32 *smFlags GSSEAP_UNUSED)
 685 {
 686     krb5_error_code code;
 687     krb5_context krbContext;
 688     krb5_data data;
 689     krb5_checksum cksum;
 690     krb5_boolean valid = FALSE;
 691 #ifdef HAVE_HEIMDAL_VERSION
 692     krb5_crypto krbCrypto;
 693 #endif
 694
 695     if (chanBindings == GSS_C_NO_CHANNEL_BINDINGS ||
 696         chanBindings->application_data.length == 0)
 697         return GSS_S_CONTINUE_NEEDED;
 698
 699     GSSEAP_KRB_INIT(&krbContext);
 700
 701     KRB_DATA_INIT(&data);
 702
 703     gssBufferToKrbData(&chanBindings->application_data, &data);
 704
 705     KRB_CHECKSUM_INIT(&cksum, ctx->checksumType, inputToken);
 706
 707 #ifdef HAVE_HEIMDAL_VERSION
 708     code = krb5_crypto_init(krbContext, &ctx->rfc3961Key, 0, &krbCrypto);
 709     if (code != 0) {
 710         *minor = code;
 711         return GSS_S_FAILURE;
 712     }
 713
 714     code = krb5_verify_checksum(krbContext, krbCrypto,
 715                                 KEY_USAGE_GSSEAP_CHBIND_MIC,
 716                                 data.data, data.length, &cksum);
 717     if (code == KRB5KRB_AP_ERR_BAD_INTEGRITY) {
 718         code = 0;
 719         valid = FALSE;
 720     } else if (code == 0) {
 721         valid = TRUE;
 722     }
 723
 724     krb5_crypto_destroy(krbContext, krbCrypto);
 725 #else
 726     code = krb5_c_verify_checksum(krbContext, &ctx->rfc3961Key,
 727                                   KEY_USAGE_GSSEAP_CHBIND_MIC,
 728                                   &data, &cksum, &valid);
 729 #endif /* HAVE_HEIMDAL_VERSION */
 730     if (code != 0) {
 731         *minor = code;
 732         return GSS_S_FAILURE;
 733     }
 734
 735     if (valid == FALSE) {
 736         *minor = GSSEAP_BINDINGS_MISMATCH;
 737         return GSS_S_BAD_BINDINGS;
 738     }
 739
 740     ctx->flags |= CTX_FLAG_CHANNEL_BINDINGS_VERIFIED;
 741
 742     *minor = 0;
 743     return GSS_S_CONTINUE_NEEDED;
 744 }
 745
 746 static OM_uint32
 747 eapGssSmAcceptInitiatorMIC(OM_uint32 *minor,
 748                            gss_cred_id_t cred GSSEAP_UNUSED,
 749                            gss_ctx_id_t ctx,
 750                            gss_const_name_t target GSSEAP_UNUSED,
 751                            gss_OID mech GSSEAP_UNUSED,
 752                            OM_uint32 reqFlags GSSEAP_UNUSED,
 753                            OM_uint32 timeReq GSSEAP_UNUSED,
 754                            gss_channel_bindings_t chanBindings,
 755                            gss_buffer_t inputToken,
 756                            gss_buffer_t outputToken GSSEAP_UNUSED,
 757                            OM_uint32 *smFlags GSSEAP_UNUSED)
 758 {
 759     OM_uint32 major;
 760
 761     /*
 762      * The channel binding token is optional, however if the caller indicated
 763      * bindings we must raise an error if it was absent.
 764      *
 765      * In the future, we might use a context option to allow the caller to
 766      * indicate that missing bindings are acceptable.
 767      */
 768     if (chanBindings != NULL &&
 769         chanBindings->application_data.length != 0 &&
 770         (ctx->flags & CTX_FLAG_CHANNEL_BINDINGS_VERIFIED) == 0) {
 771         *minor = GSSEAP_MISSING_BINDINGS;
 772         return GSS_S_BAD_BINDINGS;
 773     }
 774
 775     major = gssEapVerifyTokenMIC(minor, ctx, inputToken);
 776     if (GSS_ERROR(major))
 777         return major;
 778
 779     GSSEAP_SM_TRANSITION_NEXT(ctx);
 780
 781     *minor = 0;
 782     return GSS_S_CONTINUE_NEEDED;
 783 }
 784
 785 #ifdef GSSEAP_ENABLE_REAUTH
 786 static OM_uint32
 787 eapGssSmAcceptReauthCreds(OM_uint32 *minor,
 788                           gss_cred_id_t cred,
 789                           gss_ctx_id_t ctx,
 790                           gss_const_name_t target GSSEAP_UNUSED,
 791                           gss_OID mech GSSEAP_UNUSED,
 792                           OM_uint32 reqFlags GSSEAP_UNUSED,
 793                           OM_uint32 timeReq GSSEAP_UNUSED,
 794                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 795                           gss_buffer_t inputToken GSSEAP_UNUSED,
 796                           gss_buffer_t outputToken,
 797                           OM_uint32 *smFlags GSSEAP_UNUSED)
 798 {
 799     OM_uint32 major;
 800
 801     /*
 802      * If we're built with fast reauthentication enabled, then
 803      * fabricate a ticket from the initiator to ourselves.
 804      */
 805     major = gssEapMakeReauthCreds(minor, ctx, cred, outputToken);
 806     if (major == GSS_S_UNAVAILABLE)
 807         major = GSS_S_COMPLETE;
 808     if (major == GSS_S_COMPLETE)
 809         major = GSS_S_CONTINUE_NEEDED;
 810
 811     return major;
 812 }
 813 #endif
 814
 815 static OM_uint32
 816 eapGssSmAcceptAcceptorMIC(OM_uint32 *minor,
 817                           gss_cred_id_t cred GSSEAP_UNUSED,
 818                           gss_ctx_id_t ctx,
 819                           gss_const_name_t target GSSEAP_UNUSED,
 820                           gss_OID mech GSSEAP_UNUSED,
 821                           OM_uint32 reqFlags GSSEAP_UNUSED,
 822                           OM_uint32 timeReq GSSEAP_UNUSED,
 823                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 824                           gss_buffer_t inputToken GSSEAP_UNUSED,
 825                           gss_buffer_t outputToken,
 826                           OM_uint32 *smFlags)
 827 {
 828     OM_uint32 major;
 829
 830     major = gssEapMakeTokenMIC(minor, ctx, outputToken);
 831     if (GSS_ERROR(major))
 832         return major;
 833
 834     GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 835
 836     *minor = 0;
 837     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 838
 839     return GSS_S_COMPLETE;
 840 }
 841
 842 static struct gss_eap_sm eapGssAcceptorSm[] = {
 843     {
 844         ITOK_TYPE_ACCEPTOR_NAME_REQ,
 845         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 846         GSSEAP_STATE_INITIAL,
 847         0,
 848         eapGssSmAcceptAcceptorName
 849     },
 850 #ifdef GSSEAP_DEBUG
 851     {
 852         ITOK_TYPE_VENDOR_INFO,
 853         ITOK_TYPE_NONE,
 854         GSSEAP_STATE_INITIAL,
 855         0,
 856         eapGssSmAcceptVendorInfo,
 857     },
 858 #endif
 859 #ifdef GSSEAP_ENABLE_REAUTH
 860     {
 861         ITOK_TYPE_REAUTH_REQ,
 862         ITOK_TYPE_REAUTH_RESP,
 863         GSSEAP_STATE_INITIAL,
 864         0,
 865         eapGssSmAcceptGssReauth,
 866     },
 867 #endif
 868     {
 869         ITOK_TYPE_NONE,
 870         ITOK_TYPE_EAP_REQ,
 871         GSSEAP_STATE_INITIAL,
 872         SM_ITOK_FLAG_REQUIRED,
 873         eapGssSmAcceptIdentity,
 874     },
 875     {
 876         ITOK_TYPE_EAP_RESP,
 877         ITOK_TYPE_EAP_REQ,
 878         GSSEAP_STATE_AUTHENTICATE,
 879         SM_ITOK_FLAG_REQUIRED,
 880         eapGssSmAcceptAuthenticate
 881     },
 882     {
 883         ITOK_TYPE_GSS_FLAGS,
 884         ITOK_TYPE_NONE,
 885         GSSEAP_STATE_INITIATOR_EXTS,
 886         0,
 887         eapGssSmAcceptGssFlags
 888     },
 889     {
 890         ITOK_TYPE_GSS_CHANNEL_BINDINGS,
 891         ITOK_TYPE_NONE,
 892         GSSEAP_STATE_INITIATOR_EXTS,
 893         0,
 894         eapGssSmAcceptGssChannelBindings,
 895     },
 896     {
 897         ITOK_TYPE_INITIATOR_MIC,
 898         ITOK_TYPE_NONE,
 899         GSSEAP_STATE_INITIATOR_EXTS,
 900         SM_ITOK_FLAG_REQUIRED,
 901         eapGssSmAcceptInitiatorMIC,
 902     },
 903 #ifdef GSSEAP_ENABLE_REAUTH
 904     {
 905         ITOK_TYPE_NONE,
 906         ITOK_TYPE_REAUTH_CREDS,
 907         GSSEAP_STATE_ACCEPTOR_EXTS,
 908         0,
 909         eapGssSmAcceptReauthCreds,
 910     },
 911 #endif
 912     {
 913         ITOK_TYPE_NONE,
 914         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 915         GSSEAP_STATE_ACCEPTOR_EXTS,
 916         0,
 917         eapGssSmAcceptAcceptorName
 918     },
 919     {
 920         ITOK_TYPE_NONE,
 921         ITOK_TYPE_ACCEPTOR_MIC,
 922         GSSEAP_STATE_ACCEPTOR_EXTS,
 923         0,
 924         eapGssSmAcceptAcceptorMIC
 925     },
 926 };
 927
 928 OM_uint32
 929 gssEapAcceptSecContext(OM_uint32 *minor,
 930                        gss_ctx_id_t ctx,
 931                        gss_cred_id_t cred,
 932                        gss_buffer_t input_token,
 933                        gss_channel_bindings_t input_chan_bindings,
 934                        gss_name_t *src_name,
 935                        gss_OID *mech_type,
 936                        gss_buffer_t output_token,
 937                        OM_uint32 *ret_flags,
 938                        OM_uint32 *time_rec,
 939                        gss_cred_id_t *delegated_cred_handle)
 940 {
 941     OM_uint32 major, tmpMinor;
 942
 943     if (cred == GSS_C_NO_CREDENTIAL) {
 944         if (ctx->cred == GSS_C_NO_CREDENTIAL) {
 945             major = gssEapAcquireCred(minor,
 946                                       GSS_C_NO_NAME,
 947                                       GSS_C_INDEFINITE,
 948                                       GSS_C_NO_OID_SET,
 949                                       GSS_C_ACCEPT,
 950                                       &ctx->cred,
 951                                       NULL,
 952                                       NULL);
 953             if (GSS_ERROR(major))
 954                 goto cleanup;
 955         }
 956
 957         cred = ctx->cred;
 958     }
 959
 960     /*
 961      * Previously we acquired the credential mutex here, but it should not be
 962      * necessary as the acceptor does not access any mutable elements of the
 963      * credential handle.
 964      */
 965
 966     if (cred->name != GSS_C_NO_NAME) {
 967         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 968         if (GSS_ERROR(major))
 969             goto cleanup;
 970     }
 971
 972     major = gssEapSmStep(minor,
 973                          cred,
 974                          ctx,
 975                          GSS_C_NO_NAME,
 976                          GSS_C_NO_OID,
 977                          0,
 978                          GSS_C_INDEFINITE,
 979                          input_chan_bindings,
 980                          input_token,
 981                          output_token,
 982                          eapGssAcceptorSm,
 983                          sizeof(eapGssAcceptorSm) / sizeof(eapGssAcceptorSm[0]));
 984     if (GSS_ERROR(major))
 985         goto cleanup;
 986
 987     if (mech_type != NULL) {
 988         OM_uint32 tmpMajor;
 989
 990         tmpMajor = gssEapCanonicalizeOid(&tmpMinor, ctx->mechanismUsed, 0, mech_type);
 991         if (GSS_ERROR(tmpMajor)) {
 992             major = tmpMajor;
 993             *minor = tmpMinor;
 994             goto cleanup;
 995         }
 996     }
 997     if (ret_flags != NULL)
 998         *ret_flags = ctx->gssFlags;
 999     if (delegated_cred_handle != NULL)
1000         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1001
1002     if (major == GSS_S_COMPLETE) {
1003         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
1004             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
1005             if (GSS_ERROR(major))
1006                 goto cleanup;
1007         }
1008         if (time_rec != NULL) {
1009             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
1010             if (GSS_ERROR(major))
1011                 goto cleanup;
1012         }
1013     }
1014
1015     GSSEAP_ASSERT(CTX_IS_ESTABLISHED(ctx) || major == GSS_S_CONTINUE_NEEDED);
1016
1017 cleanup:
1018     return major;
1019 }
1020
1021 #ifdef GSSEAP_ENABLE_REAUTH
1022 static OM_uint32
1023 acceptReadyKrb(OM_uint32 *minor,
1024                gss_ctx_id_t ctx,
1025                gss_cred_id_t cred,
1026                const gss_name_t initiator,
1027                const gss_OID mech,
1028                OM_uint32 timeRec)
1029 {
1030     OM_uint32 major;
1031
1032     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
1033     if (GSS_ERROR(major))
1034         return major;
1035
1036     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
1037     if (GSS_ERROR(major))
1038         return major;
1039
1040     *minor = 0;
1041     return GSS_S_COMPLETE;
1042 }
1043
1044 static OM_uint32
1045 eapGssSmAcceptGssReauth(OM_uint32 *minor,
1046                         gss_cred_id_t cred,
1047                         gss_ctx_id_t ctx,
1048                         gss_const_name_t target GSSEAP_UNUSED,
1049                         gss_OID mech,
1050                         OM_uint32 reqFlags GSSEAP_UNUSED,
1051                         OM_uint32 timeReq GSSEAP_UNUSED,
1052                         gss_channel_bindings_t chanBindings,
1053                         gss_buffer_t inputToken,
1054                         gss_buffer_t outputToken,
1055                         OM_uint32 *smFlags)
1056 {
1057     OM_uint32 major, tmpMinor;
1058     gss_name_t krbInitiator = GSS_C_NO_NAME;
1059     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
1060
1061     /*
1062      * If we're built with fast reauthentication support, it's valid
1063      * for an initiator to send a GSS reauthentication token as its
1064      * initial context token, causing us to short-circuit the state
1065      * machine and process Kerberos GSS messages instead.
1066      */
1067
1068     ctx->flags |= CTX_FLAG_KRB_REAUTH;
1069
1070     major = gssAcceptSecContext(minor,
1071                                 &ctx->reauthCtx,
1072                                 cred->reauthCred,
1073                                 inputToken,
1074                                 chanBindings,
1075                                 &krbInitiator,
1076                                 &mech,
1077                                 outputToken,
1078                                 &gssFlags,
1079                                 &timeRec,
1080                                 NULL);
1081     if (major == GSS_S_COMPLETE) {
1082         major = acceptReadyKrb(minor, ctx, cred,
1083                                krbInitiator, mech, timeRec);
1084         if (major == GSS_S_COMPLETE) {
1085             GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
1086         }
1087         ctx->gssFlags = gssFlags;
1088     } else if (GSS_ERROR(major) &&
1089         (*smFlags & SM_FLAG_INPUT_TOKEN_CRITICAL) == 0) {
1090         /* pretend reauthentication attempt never happened */
1091         gssDeleteSecContext(&tmpMinor, &ctx->reauthCtx, GSS_C_NO_BUFFER);
1092         ctx->flags &= ~(CTX_FLAG_KRB_REAUTH);
1093         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_INITIAL);
1094         major = GSS_S_CONTINUE_NEEDED;
1095     }
1096
1097     gssReleaseName(&tmpMinor, &krbInitiator);
1098
1099     return major;
1100 }
1101 #endif /* GSSEAP_ENABLE_REAUTH */
1102
1103 OM_uint32 GSSAPI_CALLCONV
1104 gss_accept_sec_context(OM_uint32 *minor,
1105                        gss_ctx_id_t *context_handle,
1106 #ifdef HAVE_HEIMDAL_VERSION
1107                        gss_const_cred_id_t cred,
1108 #else
1109                        gss_cred_id_t cred,
1110 #endif
1111                        gss_buffer_t input_token,
1112                        gss_channel_bindings_t input_chan_bindings,
1113                        gss_name_t *src_name,
1114                        gss_OID *mech_type,
1115                        gss_buffer_t output_token,
1116                        OM_uint32 *ret_flags,
1117                        OM_uint32 *time_rec,
1118                        gss_cred_id_t *delegated_cred_handle)
1119 {
1120     OM_uint32 major, tmpMinor;
1121     gss_ctx_id_t ctx = *context_handle;
1122
1123     *minor = 0;
1124
1125     output_token->length = 0;
1126     output_token->value = NULL;
1127
1128     if (src_name != NULL)
1129         *src_name = GSS_C_NO_NAME;
1130
1131     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
1132         *minor = GSSEAP_TOK_TRUNC;
1133         return GSS_S_DEFECTIVE_TOKEN;
1134     }
1135
1136     if (ctx == GSS_C_NO_CONTEXT) {
1137         major = gssEapAllocContext(minor, &ctx);
1138         if (GSS_ERROR(major))
1139             return major;
1140
1141         *context_handle = ctx;
1142     }
1143
1144     GSSEAP_MUTEX_LOCK(&ctx->mutex);
1145
1146     major = gssEapAcceptSecContext(minor,
1147                                    ctx,
1148                                    (gss_cred_id_t)cred,
1149                                    input_token,
1150                                    input_chan_bindings,
1151                                    src_name,
1152                                    mech_type,
1153                                    output_token,
1154                                    ret_flags,
1155                                    time_rec,
1156                                    delegated_cred_handle);
1157
1158     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
1159
1160     if (GSS_ERROR(major))
1161         gssEapReleaseContext(&tmpMinor, context_handle);
1162
1163     gssEapTraceStatus("gss_accept_sec_context", major, *minor);
1164
1165     return major;
1166 }