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_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_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_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_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(
 447                          OM_uint32 *minor,
 448                          struct rs_packet *response)
 449 {
 450     rs_avp **vps;
 451     rs_const_avp  *vp = NULL;
 452     OM_uint32 major;
 453     const char * reply_message = NULL;
 454     size_t reply_length = 0;
 455
 456     rs_packet_avps(response, &vps);
 457     major = gssEapRadiusGetRawAvp(minor, *vps,
 458                                   PW_REPLY_MESSAGE, 0, &vp);
 459     if (!GSS_ERROR(major)) {
 460         reply_message = rs_avp_string_value(vp);
 461         reply_length = rs_avp_length(vp);
 462     }
 463
 464     major = gssEapRadiusGetRawAvp(minor, *vps,
 465                                   PW_ERROR_CAUSE, 0, &vp);
 466     if (!GSS_ERROR(major)) {
 467         switch (rs_avp_integer_value(vp)) {
 468             /* Values from http://www.iana.org/assignments/radius-types/radius-types.xhtml#radius-types-18                                                      */
 469         case 502: /*request not routable (proxy)*/
 470             *minor = GSSEAP_RADIUS_UNROUTABLE;
 471             break;
 472         case 501: /*administratively prohibited*/
 473             *minor = GSSEAP_RADIUS_ADMIN_PROHIBIT;
 474             break;
 475
 476         default:
 477             *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 478             break;
 479         }
 480     } else *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 481
 482     if (reply_message)
 483         gssEapSaveStatusInfo(*minor, "%s: %.*s", error_message(*minor),
 484                              reply_length, reply_message);
 485     else gssEapSaveStatusInfo( *minor, "%s", error_message(*minor));
 486     return GSS_S_DEFECTIVE_CREDENTIAL;
 487 }
 488 /*
 489  * Process a EAP response from the initiator.
 490  */
 491 static OM_uint32
 492 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 493                            gss_cred_id_t cred,
 494                            gss_ctx_id_t ctx,
 495                            gss_name_t target GSSEAP_UNUSED,
 496                            gss_OID mech GSSEAP_UNUSED,
 497                            OM_uint32 reqFlags GSSEAP_UNUSED,
 498                            OM_uint32 timeReq GSSEAP_UNUSED,
 499                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 500                            gss_buffer_t inputToken,
 501                            gss_buffer_t outputToken,
 502                            OM_uint32 *smFlags)
 503 {
 504     OM_uint32 major, tmpMinor;
 505     struct rs_connection *rconn;
 506     struct rs_request *request = NULL;
 507     struct rs_packet *req = NULL, *resp = NULL;
 508     int isAccessChallenge;
 509
 510     if (ctx->acceptorCtx.radContext == NULL) {
 511         /* May be NULL from an imported partial context */
 512         major = createRadiusHandle(minor, cred, ctx);
 513         if (GSS_ERROR(major))
 514             goto cleanup;
 515     }
 516
 517     if (isIdentityResponseP(inputToken)) {
 518         major = importInitiatorIdentity(minor, ctx, inputToken);
 519         if (GSS_ERROR(major))
 520             return major;
 521     }
 522
 523     rconn = ctx->acceptorCtx.radConn;
 524
 525     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 526         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 527         goto cleanup;
 528     }
 529
 530     major = setInitiatorIdentity(minor, ctx, req);
 531     if (GSS_ERROR(major))
 532         goto cleanup;
 533
 534     major = setAcceptorIdentity(minor, ctx, req);
 535     if (GSS_ERROR(major))
 536         goto cleanup;
 537
 538     major = gssEapRadiusAddAvp(minor, req,
 539                                PW_EAP_MESSAGE, 0, inputToken);
 540     if (GSS_ERROR(major))
 541         goto cleanup;
 542
 543     if (ctx->acceptorCtx.state.length != 0) {
 544         major = gssEapRadiusAddAvp(minor, req, PW_STATE, 0,
 545                                    &ctx->acceptorCtx.state);
 546         if (GSS_ERROR(major))
 547             goto cleanup;
 548
 549         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 550     }
 551
 552     if (rs_request_create(rconn, &request) != 0) {
 553         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 554         goto cleanup;
 555     }
 556
 557     rs_request_add_reqpkt(request, req);
 558     req = NULL;
 559
 560     if (rs_request_send(request, &resp) != 0) {
 561         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 562         goto cleanup;
 563     }
 564
 565     GSSEAP_ASSERT(resp != NULL);
 566
 567     isAccessChallenge = 0;
 568
 569     switch (rs_packet_code(resp)) {
 570     case PW_ACCESS_CHALLENGE:
 571         isAccessChallenge = 1;
 572         break;
 573     case PW_ACCESS_ACCEPT:
 574         break;
 575     case PW_ACCESS_REJECT:
 576         major = eapGssAcceptHandleReject( minor, resp);
 577         goto cleanup;
 578         break;
 579     default:
 580         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 581         major = GSS_S_FAILURE;
 582         goto cleanup;
 583         break;
 584     }
 585
 586     major = gssEapRadiusGetAvp(minor, resp, PW_EAP_MESSAGE, 0,
 587                                outputToken, TRUE);
 588     if (major == GSS_S_UNAVAILABLE && isAccessChallenge) {
 589         *minor = GSSEAP_MISSING_EAP_REQUEST;
 590         major = GSS_S_DEFECTIVE_TOKEN;
 591         goto cleanup;
 592     } else if (GSS_ERROR(major))
 593         goto cleanup;
 594
 595     if (isAccessChallenge) {
 596         major = gssEapRadiusGetAvp(minor, resp, PW_STATE, 0,
 597                                    &ctx->acceptorCtx.state, TRUE);
 598         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 599             goto cleanup;
 600     } else {
 601         rs_avp **vps;
 602
 603         rs_packet_avps(resp, &vps);
 604
 605         ctx->acceptorCtx.vps = *vps;
 606         *vps = NULL;
 607
 608         major = acceptReadyEap(minor, ctx, cred);
 609         if (GSS_ERROR(major))
 610             goto cleanup;
 611
 612         GSSEAP_SM_TRANSITION_NEXT(ctx);
 613     }
 614
 615     major = GSS_S_CONTINUE_NEEDED;
 616     *minor = 0;
 617     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 618
 619 cleanup:
 620     if (request != NULL)
 621         rs_request_destroy(request);
 622     if (req != NULL)
 623         rs_packet_destroy(req);
 624     if (resp != NULL)
 625         rs_packet_destroy(resp);
 626     if (GSSEAP_SM_STATE(ctx) == GSSEAP_STATE_INITIATOR_EXTS) {
 627         GSSEAP_ASSERT(major == GSS_S_CONTINUE_NEEDED);
 628
 629         rs_conn_destroy(ctx->acceptorCtx.radConn);
 630         ctx->acceptorCtx.radConn = NULL;
 631     }
 632
 633     return major;
 634 }
 635
 636 static OM_uint32
 637 eapGssSmAcceptGssFlags(OM_uint32 *minor,
 638                        gss_cred_id_t cred GSSEAP_UNUSED,
 639                        gss_ctx_id_t ctx,
 640                        gss_name_t target GSSEAP_UNUSED,
 641                        gss_OID mech GSSEAP_UNUSED,
 642                        OM_uint32 reqFlags GSSEAP_UNUSED,
 643                        OM_uint32 timeReq GSSEAP_UNUSED,
 644                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 645                        gss_buffer_t inputToken,
 646                        gss_buffer_t outputToken GSSEAP_UNUSED,
 647                        OM_uint32 *smFlags GSSEAP_UNUSED)
 648 {
 649     unsigned char *p;
 650     OM_uint32 initiatorGssFlags;
 651
 652     GSSEAP_ASSERT((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
 653
 654     if (inputToken->length < 4) {
 655         *minor = GSSEAP_TOK_TRUNC;
 656         return GSS_S_DEFECTIVE_TOKEN;
 657     }
 658
 659     /* allow flags to grow for future expansion */
 660     p = (unsigned char *)inputToken->value + inputToken->length - 4;
 661
 662     initiatorGssFlags = load_uint32_be(p);
 663     initiatorGssFlags &= GSSEAP_WIRE_FLAGS_MASK;
 664
 665     ctx->gssFlags |= initiatorGssFlags;
 666
 667     return GSS_S_CONTINUE_NEEDED;
 668 }
 669
 670 static OM_uint32
 671 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 672                                  gss_cred_id_t cred GSSEAP_UNUSED,
 673                                  gss_ctx_id_t ctx,
 674                                  gss_name_t target GSSEAP_UNUSED,
 675                                  gss_OID mech GSSEAP_UNUSED,
 676                                  OM_uint32 reqFlags GSSEAP_UNUSED,
 677                                  OM_uint32 timeReq GSSEAP_UNUSED,
 678                                  gss_channel_bindings_t chanBindings,
 679                                  gss_buffer_t inputToken,
 680                                  gss_buffer_t outputToken GSSEAP_UNUSED,
 681                                  OM_uint32 *smFlags GSSEAP_UNUSED)
 682 {
 683     krb5_error_code code;
 684     krb5_context krbContext;
 685     krb5_data data;
 686     krb5_checksum cksum;
 687     krb5_boolean valid = FALSE;
 688
 689     if (chanBindings == GSS_C_NO_CHANNEL_BINDINGS ||
 690         chanBindings->application_data.length == 0)
 691         return GSS_S_CONTINUE_NEEDED;
 692
 693     GSSEAP_KRB_INIT(&krbContext);
 694
 695     KRB_DATA_INIT(&data);
 696
 697     gssBufferToKrbData(&chanBindings->application_data, &data);
 698
 699     KRB_CHECKSUM_INIT(&cksum, ctx->checksumType, inputToken);
 700
 701     code = krb5_c_verify_checksum(krbContext, &ctx->rfc3961Key,
 702                                   KEY_USAGE_GSSEAP_CHBIND_MIC,
 703                                   &data, &cksum, &valid);
 704     if (code != 0) {
 705         *minor = code;
 706         return GSS_S_FAILURE;
 707     }
 708
 709     if (valid == FALSE) {
 710         *minor = GSSEAP_BINDINGS_MISMATCH;
 711         return GSS_S_BAD_BINDINGS;
 712     }
 713
 714     ctx->flags |= CTX_FLAG_CHANNEL_BINDINGS_VERIFIED;
 715
 716     *minor = 0;
 717     return GSS_S_CONTINUE_NEEDED;
 718 }
 719
 720 static OM_uint32
 721 eapGssSmAcceptInitiatorMIC(OM_uint32 *minor,
 722                            gss_cred_id_t cred GSSEAP_UNUSED,
 723                            gss_ctx_id_t ctx,
 724                            gss_name_t target GSSEAP_UNUSED,
 725                            gss_OID mech GSSEAP_UNUSED,
 726                            OM_uint32 reqFlags GSSEAP_UNUSED,
 727                            OM_uint32 timeReq GSSEAP_UNUSED,
 728                            gss_channel_bindings_t chanBindings,
 729                            gss_buffer_t inputToken,
 730                            gss_buffer_t outputToken GSSEAP_UNUSED,
 731                            OM_uint32 *smFlags GSSEAP_UNUSED)
 732 {
 733     OM_uint32 major;
 734
 735     /*
 736      * The channel binding token is optional, however if the caller indicated
 737      * bindings we must raise an error if it was absent.
 738      *
 739      * In the future, we might use a context option to allow the caller to
 740      * indicate that missing bindings are acceptable.
 741      */
 742     if (chanBindings != NULL &&
 743         chanBindings->application_data.length != 0 &&
 744         (ctx->flags & CTX_FLAG_CHANNEL_BINDINGS_VERIFIED) == 0) {
 745         *minor = GSSEAP_MISSING_BINDINGS;
 746         return GSS_S_BAD_BINDINGS;
 747     }
 748
 749     major = gssEapVerifyTokenMIC(minor, ctx, inputToken);
 750     if (GSS_ERROR(major))
 751         return major;
 752
 753     GSSEAP_SM_TRANSITION_NEXT(ctx);
 754
 755     *minor = 0;
 756     return GSS_S_CONTINUE_NEEDED;
 757 }
 758
 759 #ifdef GSSEAP_ENABLE_REAUTH
 760 static OM_uint32
 761 eapGssSmAcceptReauthCreds(OM_uint32 *minor,
 762                           gss_cred_id_t cred,
 763                           gss_ctx_id_t ctx,
 764                           gss_name_t target GSSEAP_UNUSED,
 765                           gss_OID mech GSSEAP_UNUSED,
 766                           OM_uint32 reqFlags GSSEAP_UNUSED,
 767                           OM_uint32 timeReq GSSEAP_UNUSED,
 768                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 769                           gss_buffer_t inputToken GSSEAP_UNUSED,
 770                           gss_buffer_t outputToken,
 771                           OM_uint32 *smFlags GSSEAP_UNUSED)
 772 {
 773     OM_uint32 major;
 774
 775     /*
 776      * If we're built with fast reauthentication enabled, then
 777      * fabricate a ticket from the initiator to ourselves.
 778      */
 779     major = gssEapMakeReauthCreds(minor, ctx, cred, outputToken);
 780     if (major == GSS_S_UNAVAILABLE)
 781         major = GSS_S_COMPLETE;
 782     if (major == GSS_S_COMPLETE)
 783         major = GSS_S_CONTINUE_NEEDED;
 784
 785     return major;
 786 }
 787 #endif
 788
 789 static OM_uint32
 790 eapGssSmAcceptAcceptorMIC(OM_uint32 *minor,
 791                           gss_cred_id_t cred GSSEAP_UNUSED,
 792                           gss_ctx_id_t ctx,
 793                           gss_name_t target GSSEAP_UNUSED,
 794                           gss_OID mech GSSEAP_UNUSED,
 795                           OM_uint32 reqFlags GSSEAP_UNUSED,
 796                           OM_uint32 timeReq GSSEAP_UNUSED,
 797                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 798                           gss_buffer_t inputToken GSSEAP_UNUSED,
 799                           gss_buffer_t outputToken,
 800                           OM_uint32 *smFlags)
 801 {
 802     OM_uint32 major;
 803
 804     major = gssEapMakeTokenMIC(minor, ctx, outputToken);
 805     if (GSS_ERROR(major))
 806         return major;
 807
 808     GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 809
 810     *minor = 0;
 811     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 812
 813     return GSS_S_COMPLETE;
 814 }
 815
 816 static struct gss_eap_sm eapGssAcceptorSm[] = {
 817     {
 818         ITOK_TYPE_ACCEPTOR_NAME_REQ,
 819         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 820         GSSEAP_STATE_INITIAL,
 821         0,
 822         eapGssSmAcceptAcceptorName
 823     },
 824 #ifdef GSSEAP_DEBUG
 825     {
 826         ITOK_TYPE_VENDOR_INFO,
 827         ITOK_TYPE_NONE,
 828         GSSEAP_STATE_INITIAL,
 829         0,
 830         eapGssSmAcceptVendorInfo,
 831     },
 832 #endif
 833 #ifdef GSSEAP_ENABLE_REAUTH
 834     {
 835         ITOK_TYPE_REAUTH_REQ,
 836         ITOK_TYPE_REAUTH_RESP,
 837         GSSEAP_STATE_INITIAL,
 838         0,
 839         eapGssSmAcceptGssReauth,
 840     },
 841 #endif
 842     {
 843         ITOK_TYPE_NONE,
 844         ITOK_TYPE_EAP_REQ,
 845         GSSEAP_STATE_INITIAL,
 846         SM_ITOK_FLAG_REQUIRED,
 847         eapGssSmAcceptIdentity,
 848     },
 849     {
 850         ITOK_TYPE_EAP_RESP,
 851         ITOK_TYPE_EAP_REQ,
 852         GSSEAP_STATE_AUTHENTICATE,
 853         SM_ITOK_FLAG_REQUIRED,
 854         eapGssSmAcceptAuthenticate
 855     },
 856     {
 857         ITOK_TYPE_GSS_FLAGS,
 858         ITOK_TYPE_NONE,
 859         GSSEAP_STATE_INITIATOR_EXTS,
 860         0,
 861         eapGssSmAcceptGssFlags
 862     },
 863     {
 864         ITOK_TYPE_GSS_CHANNEL_BINDINGS,
 865         ITOK_TYPE_NONE,
 866         GSSEAP_STATE_INITIATOR_EXTS,
 867         0,
 868         eapGssSmAcceptGssChannelBindings,
 869     },
 870     {
 871         ITOK_TYPE_INITIATOR_MIC,
 872         ITOK_TYPE_NONE,
 873         GSSEAP_STATE_INITIATOR_EXTS,
 874         SM_ITOK_FLAG_REQUIRED,
 875         eapGssSmAcceptInitiatorMIC,
 876     },
 877 #ifdef GSSEAP_ENABLE_REAUTH
 878     {
 879         ITOK_TYPE_NONE,
 880         ITOK_TYPE_REAUTH_CREDS,
 881         GSSEAP_STATE_ACCEPTOR_EXTS,
 882         0,
 883         eapGssSmAcceptReauthCreds,
 884     },
 885 #endif
 886     {
 887         ITOK_TYPE_NONE,
 888         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 889         GSSEAP_STATE_ACCEPTOR_EXTS,
 890         0,
 891         eapGssSmAcceptAcceptorName
 892     },
 893     {
 894         ITOK_TYPE_NONE,
 895         ITOK_TYPE_ACCEPTOR_MIC,
 896         GSSEAP_STATE_ACCEPTOR_EXTS,
 897         0,
 898         eapGssSmAcceptAcceptorMIC
 899     },
 900 };
 901
 902 OM_uint32
 903 gssEapAcceptSecContext(OM_uint32 *minor,
 904                        gss_ctx_id_t ctx,
 905                        gss_cred_id_t cred,
 906                        gss_buffer_t input_token,
 907                        gss_channel_bindings_t input_chan_bindings,
 908                        gss_name_t *src_name,
 909                        gss_OID *mech_type,
 910                        gss_buffer_t output_token,
 911                        OM_uint32 *ret_flags,
 912                        OM_uint32 *time_rec,
 913                        gss_cred_id_t *delegated_cred_handle)
 914 {
 915     OM_uint32 major, tmpMinor;
 916
 917     if (cred == GSS_C_NO_CREDENTIAL) {
 918         if (ctx->cred == GSS_C_NO_CREDENTIAL) {
 919             major = gssEapAcquireCred(minor,
 920                                       GSS_C_NO_NAME,
 921                                       GSS_C_INDEFINITE,
 922                                       GSS_C_NO_OID_SET,
 923                                       GSS_C_ACCEPT,
 924                                       &ctx->cred,
 925                                       NULL,
 926                                       NULL);
 927             if (GSS_ERROR(major))
 928                 goto cleanup;
 929         }
 930
 931         cred = ctx->cred;
 932     }
 933
 934     /*
 935      * Previously we acquired the credential mutex here, but it should not be
 936      * necessary as the acceptor does not access any mutable elements of the
 937      * credential handle.
 938      */
 939
 940     if (cred->name != GSS_C_NO_NAME) {
 941         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 942         if (GSS_ERROR(major))
 943             goto cleanup;
 944     }
 945
 946     major = gssEapSmStep(minor,
 947                          cred,
 948                          ctx,
 949                          GSS_C_NO_NAME,
 950                          GSS_C_NO_OID,
 951                          0,
 952                          GSS_C_INDEFINITE,
 953                          input_chan_bindings,
 954                          input_token,
 955                          output_token,
 956                          eapGssAcceptorSm,
 957                          sizeof(eapGssAcceptorSm) / sizeof(eapGssAcceptorSm[0]));
 958     if (GSS_ERROR(major))
 959         goto cleanup;
 960
 961     if (mech_type != NULL) {
 962         OM_uint32 tmpMajor;
 963
 964         tmpMajor = gssEapCanonicalizeOid(&tmpMinor, ctx->mechanismUsed, 0, mech_type);
 965         if (GSS_ERROR(tmpMajor)) {
 966             major = tmpMajor;
 967             *minor = tmpMinor;
 968             goto cleanup;
 969         }
 970     }
 971     if (ret_flags != NULL)
 972         *ret_flags = ctx->gssFlags;
 973     if (delegated_cred_handle != NULL)
 974         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 975
 976     if (major == GSS_S_COMPLETE) {
 977         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 978             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
 979             if (GSS_ERROR(major))
 980                 goto cleanup;
 981         }
 982         if (time_rec != NULL) {
 983             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
 984             if (GSS_ERROR(major))
 985                 goto cleanup;
 986         }
 987     }
 988
 989     GSSEAP_ASSERT(CTX_IS_ESTABLISHED(ctx) || major == GSS_S_CONTINUE_NEEDED);
 990
 991 cleanup:
 992     return major;
 993 }
 994
 995 #ifdef GSSEAP_ENABLE_REAUTH
 996 static OM_uint32
 997 acceptReadyKrb(OM_uint32 *minor,
 998                gss_ctx_id_t ctx,
 999                gss_cred_id_t cred,
1000                const gss_name_t initiator,
1001                const gss_OID mech,
1002                OM_uint32 timeRec)
1003 {
1004     OM_uint32 major;
1005
1006     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
1007     if (GSS_ERROR(major))
1008         return major;
1009
1010     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
1011     if (GSS_ERROR(major))
1012         return major;
1013
1014     *minor = 0;
1015     return GSS_S_COMPLETE;
1016 }
1017
1018 static OM_uint32
1019 eapGssSmAcceptGssReauth(OM_uint32 *minor,
1020                         gss_cred_id_t cred,
1021                         gss_ctx_id_t ctx,
1022                         gss_name_t target GSSEAP_UNUSED,
1023                         gss_OID mech,
1024                         OM_uint32 reqFlags GSSEAP_UNUSED,
1025                         OM_uint32 timeReq GSSEAP_UNUSED,
1026                         gss_channel_bindings_t chanBindings,
1027                         gss_buffer_t inputToken,
1028                         gss_buffer_t outputToken,
1029                         OM_uint32 *smFlags)
1030 {
1031     OM_uint32 major, tmpMinor;
1032     gss_name_t krbInitiator = GSS_C_NO_NAME;
1033     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
1034
1035     /*
1036      * If we're built with fast reauthentication support, it's valid
1037      * for an initiator to send a GSS reauthentication token as its
1038      * initial context token, causing us to short-circuit the state
1039      * machine and process Kerberos GSS messages instead.
1040      */
1041
1042     ctx->flags |= CTX_FLAG_KRB_REAUTH;
1043
1044     major = gssAcceptSecContext(minor,
1045                                 &ctx->reauthCtx,
1046                                 cred->reauthCred,
1047                                 inputToken,
1048                                 chanBindings,
1049                                 &krbInitiator,
1050                                 &mech,
1051                                 outputToken,
1052                                 &gssFlags,
1053                                 &timeRec,
1054                                 NULL);
1055     if (major == GSS_S_COMPLETE) {
1056         major = acceptReadyKrb(minor, ctx, cred,
1057                                krbInitiator, mech, timeRec);
1058         if (major == GSS_S_COMPLETE) {
1059             GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
1060         }
1061         ctx->gssFlags = gssFlags;
1062     } else if (GSS_ERROR(major) &&
1063         (*smFlags & SM_FLAG_INPUT_TOKEN_CRITICAL) == 0) {
1064         /* pretend reauthentication attempt never happened */
1065         gssDeleteSecContext(&tmpMinor, &ctx->reauthCtx, GSS_C_NO_BUFFER);
1066         ctx->flags &= ~(CTX_FLAG_KRB_REAUTH);
1067         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_INITIAL);
1068         major = GSS_S_CONTINUE_NEEDED;
1069     }
1070
1071     gssReleaseName(&tmpMinor, &krbInitiator);
1072
1073     return major;
1074 }
1075 #endif /* GSSEAP_ENABLE_REAUTH */
1076
1077 OM_uint32 GSSAPI_CALLCONV
1078 gss_accept_sec_context(OM_uint32 *minor,
1079                        gss_ctx_id_t *context_handle,
1080                        gss_cred_id_t cred,
1081                        gss_buffer_t input_token,
1082                        gss_channel_bindings_t input_chan_bindings,
1083                        gss_name_t *src_name,
1084                        gss_OID *mech_type,
1085                        gss_buffer_t output_token,
1086                        OM_uint32 *ret_flags,
1087                        OM_uint32 *time_rec,
1088                        gss_cred_id_t *delegated_cred_handle)
1089 {
1090     OM_uint32 major, tmpMinor;
1091     gss_ctx_id_t ctx = *context_handle;
1092
1093     *minor = 0;
1094
1095     output_token->length = 0;
1096     output_token->value = NULL;
1097
1098     if (src_name != NULL)
1099         *src_name = GSS_C_NO_NAME;
1100
1101     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
1102         *minor = GSSEAP_TOK_TRUNC;
1103         return GSS_S_DEFECTIVE_TOKEN;
1104     }
1105
1106     if (ctx == GSS_C_NO_CONTEXT) {
1107         major = gssEapAllocContext(minor, &ctx);
1108         if (GSS_ERROR(major))
1109             return major;
1110
1111         *context_handle = ctx;
1112     }
1113
1114     GSSEAP_MUTEX_LOCK(&ctx->mutex);
1115
1116     major = gssEapAcceptSecContext(minor,
1117                                    ctx,
1118                                    cred,
1119                                    input_token,
1120                                    input_chan_bindings,
1121                                    src_name,
1122                                    mech_type,
1123                                    output_token,
1124                                    ret_flags,
1125                                    time_rec,
1126                                    delegated_cred_handle);
1127
1128     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
1129
1130     if (GSS_ERROR(major))
1131         gssEapReleaseContext(&tmpMinor, context_handle);
1132
1133     gssEapTraceStatus("gss_accept_sec_context", major, *minor);
1134     return major;
1135 }