www.project-moonshot.org Git - mech_eap.orig/blob - init_sec_context.c

   1 /*
   2  * Copyright (c) 2010, 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 #include "gssapiP_eap.h"
  34
  35 #ifdef GSSEAP_ENABLE_REAUTH
  36 static int
  37 canReauthP(gss_cred_id_t cred);
  38
  39 static OM_uint32
  40 eapGssSmInitGssReauth(OM_uint32 *minor,
  41                       gss_cred_id_t cred,
  42                       gss_ctx_id_t ctx,
  43                       gss_name_t target,
  44                       gss_OID mech,
  45                       OM_uint32 reqFlags,
  46                       OM_uint32 timeReq,
  47                       gss_channel_bindings_t chanBindings,
  48                       gss_buffer_t inputToken,
  49                       gss_buffer_t outputToken);
  50 #endif
  51
  52 static OM_uint32
  53 policyVariableToFlag(enum eapol_bool_var variable)
  54 {
  55     OM_uint32 flag = 0;
  56
  57     switch (variable) {
  58     case EAPOL_eapSuccess:
  59         flag = CTX_FLAG_EAP_SUCCESS;
  60         break;
  61     case EAPOL_eapRestart:
  62         flag = CTX_FLAG_EAP_RESTART;
  63         break;
  64     case EAPOL_eapFail:
  65         flag = CTX_FLAG_EAP_FAIL;
  66         break;
  67     case EAPOL_eapResp:
  68         flag = CTX_FLAG_EAP_RESP;
  69         break;
  70     case EAPOL_eapNoResp:
  71         flag = CTX_FLAG_EAP_NO_RESP;
  72         break;
  73     case EAPOL_eapReq:
  74         flag = CTX_FLAG_EAP_REQ;
  75         break;
  76     case EAPOL_portEnabled:
  77         flag = CTX_FLAG_EAP_PORT_ENABLED;
  78         break;
  79     case EAPOL_altAccept:
  80         flag = CTX_FLAG_EAP_ALT_ACCEPT;
  81         break;
  82     case EAPOL_altReject:
  83         flag = CTX_FLAG_EAP_ALT_REJECT;
  84         break;
  85     }
  86
  87     return flag;
  88 }
  89
  90 static struct eap_peer_config *
  91 peerGetConfig(void *ctx)
  92 {
  93     gss_ctx_id_t gssCtx = (gss_ctx_id_t)ctx;
  94
  95     return &gssCtx->initiatorCtx.eapPeerConfig;
  96 }
  97
  98 static Boolean
  99 peerGetBool(void *data, enum eapol_bool_var variable)
 100 {
 101     gss_ctx_id_t ctx = data;
 102     OM_uint32 flag;
 103
 104     if (ctx == GSS_C_NO_CONTEXT)
 105         return FALSE;
 106
 107     flag = policyVariableToFlag(variable);
 108
 109     return ((ctx->flags & flag) != 0);
 110 }
 111
 112 static void
 113 peerSetBool(void *data, enum eapol_bool_var variable,
 114             Boolean value)
 115 {
 116     gss_ctx_id_t ctx = data;
 117     OM_uint32 flag;
 118
 119     if (ctx == GSS_C_NO_CONTEXT)
 120         return;
 121
 122     flag = policyVariableToFlag(variable);
 123
 124     if (value)
 125         ctx->flags |= flag;
 126     else
 127         ctx->flags &= ~(flag);
 128 }
 129
 130 static unsigned int
 131 peerGetInt(void *data, enum eapol_int_var variable)
 132 {
 133     gss_ctx_id_t ctx = data;
 134
 135     if (ctx == GSS_C_NO_CONTEXT)
 136         return FALSE;
 137
 138     assert(CTX_IS_INITIATOR(ctx));
 139
 140     switch (variable) {
 141     case EAPOL_idleWhile:
 142         return ctx->initiatorCtx.idleWhile;
 143         break;
 144     }
 145
 146     return 0;
 147 }
 148
 149 static void
 150 peerSetInt(void *data, enum eapol_int_var variable,
 151            unsigned int value)
 152 {
 153     gss_ctx_id_t ctx = data;
 154
 155     if (ctx == GSS_C_NO_CONTEXT)
 156         return;
 157
 158     assert(CTX_IS_INITIATOR(ctx));
 159
 160     switch (variable) {
 161     case EAPOL_idleWhile:
 162         ctx->initiatorCtx.idleWhile = value;
 163         break;
 164     }
 165 }
 166
 167 static struct wpabuf *
 168 peerGetEapReqData(void *ctx)
 169 {
 170     gss_ctx_id_t gssCtx = (gss_ctx_id_t)ctx;
 171
 172     return &gssCtx->initiatorCtx.reqData;
 173 }
 174
 175 static void
 176 peerSetConfigBlob(void *ctx, struct wpa_config_blob *blob)
 177 {
 178 }
 179
 180 static const struct wpa_config_blob *
 181 peerGetConfigBlob(void *ctx, const char *name)
 182 {
 183     return NULL;
 184 }
 185
 186 static void
 187 peerNotifyPending(void *ctx)
 188 {
 189 }
 190
 191 static struct eapol_callbacks gssEapPolicyCallbacks = {
 192     peerGetConfig,
 193     peerGetBool,
 194     peerSetBool,
 195     peerGetInt,
 196     peerSetInt,
 197     peerGetEapReqData,
 198     peerSetConfigBlob,
 199     peerGetConfigBlob,
 200     peerNotifyPending,
 201 };
 202
 203 extern int wpa_debug_level;
 204
 205 static OM_uint32
 206 peerConfigInit(OM_uint32 *minor,
 207                gss_cred_id_t cred,
 208                gss_ctx_id_t ctx)
 209 {
 210     krb5_context krbContext;
 211     struct eap_peer_config *eapPeerConfig = &ctx->initiatorCtx.eapPeerConfig;
 212     krb5_error_code code;
 213     char *identity;
 214
 215     eapPeerConfig->identity = NULL;
 216     eapPeerConfig->identity_len = 0;
 217     eapPeerConfig->password = NULL;
 218     eapPeerConfig->password_len = 0;
 219
 220     assert(cred != GSS_C_NO_CREDENTIAL);
 221
 222     GSSEAP_KRB_INIT(&krbContext);
 223
 224     eapPeerConfig->fragment_size = 1024;
 225     wpa_debug_level = 0;
 226
 227     code = krb5_unparse_name(krbContext, cred->name->krbPrincipal, &identity);
 228     if (code != 0) {
 229         *minor = code;
 230         return GSS_S_FAILURE;
 231     }
 232
 233     eapPeerConfig->identity = (unsigned char *)identity;
 234     eapPeerConfig->identity_len = strlen(identity);
 235     eapPeerConfig->password = (unsigned char *)cred->password.value;
 236     eapPeerConfig->password_len = cred->password.length;
 237
 238     return GSS_S_COMPLETE;
 239 }
 240
 241 static OM_uint32
 242 peerConfigFree(OM_uint32 *minor,
 243                gss_ctx_id_t ctx)
 244 {
 245     krb5_context krbContext;
 246     struct eap_peer_config *eapPeerConfig = &ctx->initiatorCtx.eapPeerConfig;
 247
 248     GSSEAP_KRB_INIT(&krbContext);
 249
 250     krb5_free_unparsed_name(krbContext, (char *)eapPeerConfig->identity);
 251
 252     return GSS_S_COMPLETE;
 253 }
 254
 255 static OM_uint32
 256 initReady(OM_uint32 *minor, gss_ctx_id_t ctx, OM_uint32 reqFlags)
 257 {
 258     OM_uint32 major;
 259     const unsigned char *key;
 260     size_t keyLength;
 261     krb5_enctype encryptionType;
 262     int gotKey = 0;
 263
 264 #if 1
 265     /* XXX actually check for mutual auth */
 266     if (reqFlags & GSS_C_MUTUAL_FLAG)
 267         ctx->gssFlags |= GSS_C_MUTUAL_FLAG;
 268 #endif
 269
 270     /* Cache encryption type derived from selected mechanism OID */
 271     major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &encryptionType);
 272     if (GSS_ERROR(major))
 273         return major;
 274
 275     if (encryptionType != ENCTYPE_NULL &&
 276         eap_key_available(ctx->initiatorCtx.eap)) {
 277         key = eap_get_eapKeyData(ctx->initiatorCtx.eap, &keyLength);
 278
 279         if (keyLength >= EAP_EMSK_LEN) {
 280             major = gssEapDeriveRfc3961Key(minor,
 281                                            &key[EAP_EMSK_LEN / 2],
 282                                            EAP_EMSK_LEN / 2,
 283                                            encryptionType,
 284                                            &ctx->rfc3961Key);
 285                if (GSS_ERROR(major))
 286                    return major;
 287
 288             major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 289                                               &ctx->checksumType);
 290             if (GSS_ERROR(major))
 291                 return major;
 292             gotKey++;
 293         }
 294     }
 295
 296     if (gotKey) {
 297         ctx->encryptionType = encryptionType;
 298     } else {
 299         /*
 300          * draft-howlett-eap-gss says that integrity/confidentialty should
 301          * always be advertised as available, but if we have no keying
 302          * material it seems confusing to the caller to advertise this.
 303          */
 304         ctx->gssFlags &= ~(GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
 305     }
 306
 307     major = sequenceInit(minor,
 308                          &ctx->seqState,
 309                          ctx->recvSeq,
 310                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 311                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 312                          TRUE);
 313     if (GSS_ERROR(major))
 314         return major;
 315
 316     return GSS_S_COMPLETE;
 317 }
 318
 319 static OM_uint32
 320 initBegin(OM_uint32 *minor,
 321           gss_cred_id_t cred,
 322           gss_ctx_id_t ctx,
 323           gss_name_t target,
 324           gss_OID mech,
 325           OM_uint32 reqFlags,
 326           OM_uint32 timeReq,
 327           gss_channel_bindings_t chanBindings,
 328           gss_buffer_t inputToken,
 329           gss_buffer_t outputToken)
 330 {
 331     OM_uint32 major;
 332
 333     assert(cred != GSS_C_NO_CREDENTIAL);
 334
 335     if (cred->expiryTime)
 336         ctx->expiryTime = cred->expiryTime;
 337     else if (timeReq == 0 || timeReq == GSS_C_INDEFINITE)
 338         ctx->expiryTime = 0;
 339     else
 340         ctx->expiryTime = time(NULL) + timeReq;
 341
 342     major = gssEapDuplicateName(minor, cred->name, &ctx->initiatorName);
 343     if (GSS_ERROR(major))
 344         return major;
 345
 346     major = gssEapDuplicateName(minor, target, &ctx->acceptorName);
 347     if (GSS_ERROR(major))
 348         return major;
 349
 350     if (mech == GSS_C_NULL_OID || oidEqual(mech, GSS_EAP_MECHANISM)) {
 351         major = gssEapDefaultMech(minor, &ctx->mechanismUsed);
 352     } else if (gssEapIsConcreteMechanismOid(mech)) {
 353         if (!gssEapInternalizeOid(mech, &ctx->mechanismUsed))
 354             major = duplicateOid(minor, mech, &ctx->mechanismUsed);
 355     } else {
 356         major = GSS_S_BAD_MECH;
 357     }
 358     if (GSS_ERROR(major))
 359         return major;
 360
 361     /* If credentials were provided, check they're usable with this mech */
 362     if (!gssEapCredAvailable(cred, ctx->mechanismUsed))
 363         return GSS_S_BAD_MECH;
 364
 365     return GSS_S_COMPLETE;
 366 }
 367
 368 static OM_uint32
 369 eapGssSmInitIdentity(OM_uint32 *minor,
 370                      gss_cred_id_t cred,
 371                      gss_ctx_id_t ctx,
 372                      gss_name_t target,
 373                      gss_OID mech,
 374                      OM_uint32 reqFlags,
 375                      OM_uint32 timeReq,
 376                      gss_channel_bindings_t chanBindings,
 377                      gss_buffer_t inputToken,
 378                      gss_buffer_t outputToken)
 379 {
 380     OM_uint32 major;
 381     int initialContextToken;
 382
 383     initialContextToken = (inputToken->length == 0);
 384     if (!initialContextToken)
 385         return GSS_S_DEFECTIVE_TOKEN;
 386
 387     major = initBegin(minor, cred, ctx, target, mech,
 388                       reqFlags, timeReq, chanBindings,
 389                       inputToken, outputToken);
 390     if (GSS_ERROR(major))
 391         return major;
 392
 393     ctx->state = EAP_STATE_AUTHENTICATE;
 394
 395     return GSS_S_CONTINUE_NEEDED;
 396 }
 397
 398 static struct wpabuf emptyWpaBuffer;
 399
 400 static OM_uint32
 401 eapGssSmInitAuthenticate(OM_uint32 *minor,
 402                          gss_cred_id_t cred,
 403                          gss_ctx_id_t ctx,
 404                          gss_name_t target,
 405                          gss_OID mech,
 406                          OM_uint32 reqFlags,
 407                          OM_uint32 timeReq,
 408                          gss_channel_bindings_t chanBindings,
 409                          gss_buffer_t inputToken,
 410                          gss_buffer_t outputToken)
 411 {
 412     OM_uint32 major;
 413     OM_uint32 tmpMinor;
 414     int code;
 415     struct wpabuf *resp = NULL;
 416     int initialContextToken;
 417
 418     initialContextToken = (inputToken == GSS_C_NO_BUFFER ||
 419                            inputToken->length == 0);
 420
 421     major = peerConfigInit(minor, cred, ctx);
 422     if (GSS_ERROR(major))
 423         goto cleanup;
 424
 425     if (ctx->initiatorCtx.eap == NULL) {
 426         struct eap_config eapConfig;
 427
 428         memset(&eapConfig, 0, sizeof(eapConfig));
 429
 430         ctx->initiatorCtx.eap = eap_peer_sm_init(ctx,
 431                                                  &gssEapPolicyCallbacks,
 432                                                  ctx,
 433                                                  &eapConfig);
 434         if (ctx->initiatorCtx.eap == NULL) {
 435             major = GSS_S_FAILURE;
 436             goto cleanup;
 437         }
 438
 439         ctx->flags |= CTX_FLAG_EAP_RESTART | CTX_FLAG_EAP_PORT_ENABLED;
 440     }
 441
 442     ctx->flags |= CTX_FLAG_EAP_REQ; /* we have a Request from the acceptor */
 443
 444     wpabuf_set(&ctx->initiatorCtx.reqData,
 445                inputToken->value, inputToken->length);
 446
 447     major = GSS_S_CONTINUE_NEEDED;
 448
 449     code = eap_peer_sm_step(ctx->initiatorCtx.eap);
 450     if (ctx->flags & CTX_FLAG_EAP_RESP) {
 451         ctx->flags &= ~(CTX_FLAG_EAP_RESP);
 452
 453         resp = eap_get_eapRespData(ctx->initiatorCtx.eap);
 454     } else if (ctx->flags & CTX_FLAG_EAP_SUCCESS) {
 455         major = initReady(minor, ctx, reqFlags);
 456         if (GSS_ERROR(major))
 457             goto cleanup;
 458
 459         ctx->flags &= ~(CTX_FLAG_EAP_SUCCESS);
 460         major = GSS_S_CONTINUE_NEEDED;
 461         ctx->state = EAP_STATE_EXTENSIONS_REQ;
 462     } else if (ctx->flags & CTX_FLAG_EAP_FAIL) {
 463         major = GSS_S_DEFECTIVE_CREDENTIAL;
 464     } else if (code == 0 && initialContextToken) {
 465         resp = &emptyWpaBuffer;
 466         major = GSS_S_CONTINUE_NEEDED;
 467     } else {
 468         major = GSS_S_DEFECTIVE_TOKEN;
 469     }
 470
 471 cleanup:
 472     if (resp != NULL) {
 473         OM_uint32 tmpMajor;
 474         gss_buffer_desc respBuf;
 475
 476         assert(major == GSS_S_CONTINUE_NEEDED);
 477
 478         respBuf.length = wpabuf_len(resp);
 479         respBuf.value = (void *)wpabuf_head(resp);
 480
 481         tmpMajor = duplicateBuffer(&tmpMinor, &respBuf, outputToken);
 482         if (GSS_ERROR(tmpMajor)) {
 483             major = tmpMajor;
 484             *minor = tmpMinor;
 485         }
 486     }
 487
 488     wpabuf_set(&ctx->initiatorCtx.reqData, NULL, 0);
 489     peerConfigFree(&tmpMinor, ctx);
 490
 491     return major;
 492 }
 493
 494 static OM_uint32
 495 initGssChannelBindings(OM_uint32 *minor,
 496                        gss_ctx_id_t ctx,
 497                        gss_channel_bindings_t chanBindings,
 498                        gss_buffer_t outputToken)
 499 {
 500     OM_uint32 major;
 501     gss_buffer_desc buffer = GSS_C_EMPTY_BUFFER;
 502
 503
 504     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS)
 505         buffer = chanBindings->application_data;
 506
 507     major = gssEapWrap(minor, ctx, TRUE, GSS_C_QOP_DEFAULT,
 508                        &buffer, NULL, outputToken);
 509     if (GSS_ERROR(major))
 510         return major;
 511
 512     return GSS_S_CONTINUE_NEEDED;
 513 }
 514
 515 static OM_uint32
 516 eapGssSmInitExtensionsReq(OM_uint32 *minor,
 517                           gss_cred_id_t cred,
 518                           gss_ctx_id_t ctx,
 519                           gss_name_t target,
 520                           gss_OID mech,
 521                           OM_uint32 reqFlags,
 522                           OM_uint32 timeReq,
 523                           gss_channel_bindings_t chanBindings,
 524                           gss_buffer_t inputToken,
 525                           gss_buffer_t outputToken)
 526 {
 527     OM_uint32 major, tmpMinor;
 528     gss_buffer_desc cbToken = GSS_C_EMPTY_BUFFER;
 529
 530     major = initGssChannelBindings(minor, ctx, chanBindings, &cbToken);
 531     if (GSS_ERROR(major))
 532         return major;
 533
 534     ctx->state = EAP_STATE_EXTENSIONS_RESP;
 535
 536     major = duplicateBuffer(minor, &cbToken, outputToken);
 537     if (GSS_ERROR(major)) {
 538         gss_release_buffer(&tmpMinor, &cbToken);
 539         return major;
 540     }
 541
 542     gss_release_buffer(&tmpMinor, &cbToken);
 543
 544     return GSS_S_CONTINUE_NEEDED;
 545 }
 546
 547 static OM_uint32
 548 eapGssSmInitExtensionsResp(OM_uint32 *minor,
 549                            gss_cred_id_t cred,
 550                            gss_ctx_id_t ctx,
 551                            gss_name_t target,
 552                            gss_OID mech,
 553                            OM_uint32 reqFlags,
 554                            OM_uint32 timeReq,
 555                            gss_channel_bindings_t chanBindings,
 556                            gss_buffer_t inputToken,
 557                            gss_buffer_t outputToken)
 558 {
 559 #ifdef GSSEAP_ENABLE_REAUTH
 560     OM_uint32 major;
 561
 562     major = gssEapStoreReauthCreds(minor, ctx, cred, inputToken);
 563     if (GSS_ERROR(major))
 564         return major;
 565 #endif
 566
 567     ctx->state = EAP_STATE_ESTABLISHED;
 568
 569     return GSS_S_COMPLETE;
 570 }
 571
 572 static OM_uint32
 573 eapGssSmInitEstablished(OM_uint32 *minor,
 574                         gss_cred_id_t cred,
 575                         gss_ctx_id_t ctx,
 576                         gss_name_t target,
 577                         gss_OID mech,
 578                         OM_uint32 reqFlags,
 579                         OM_uint32 timeReq,
 580                         gss_channel_bindings_t chanBindings,
 581                         gss_buffer_t inputToken,
 582                         gss_buffer_t outputToken)
 583 {
 584     /* Called with already established context */
 585     *minor = EINVAL;
 586     return GSS_S_BAD_STATUS;
 587 }
 588
 589 static struct gss_eap_initiator_sm {
 590     enum gss_eap_token_type inputTokenType;
 591     enum gss_eap_token_type outputTokenType;
 592     OM_uint32 (*processToken)(OM_uint32 *,
 593                               gss_cred_id_t,
 594                               gss_ctx_id_t,
 595                               gss_name_t,
 596                               gss_OID,
 597                               OM_uint32,
 598                               OM_uint32,
 599                               gss_channel_bindings_t,
 600                               gss_buffer_t,
 601                               gss_buffer_t);
 602 } eapGssInitiatorSm[] = {
 603     { TOK_TYPE_NONE,    TOK_TYPE_EAP_RESP,      eapGssSmInitIdentity            },
 604     { TOK_TYPE_EAP_REQ, TOK_TYPE_EAP_RESP,      eapGssSmInitAuthenticate        },
 605     { TOK_TYPE_NONE,    TOK_TYPE_EXT_REQ,       eapGssSmInitExtensionsReq       },
 606     { TOK_TYPE_EXT_RESP,TOK_TYPE_NONE,          eapGssSmInitExtensionsResp      },
 607     { TOK_TYPE_NONE,    TOK_TYPE_NONE,          eapGssSmInitEstablished         },
 608 #ifdef GSSEAP_ENABLE_REAUTH
 609     { TOK_TYPE_GSS_REAUTH, TOK_TYPE_GSS_REAUTH, eapGssSmInitGssReauth           },
 610 #endif
 611 };
 612
 613 OM_uint32
 614 gss_init_sec_context(OM_uint32 *minor,
 615                      gss_cred_id_t cred,
 616                      gss_ctx_id_t *context_handle,
 617                      gss_name_t target_name,
 618                      gss_OID mech_type,
 619                      OM_uint32 req_flags,
 620                      OM_uint32 time_req,
 621                      gss_channel_bindings_t input_chan_bindings,
 622                      gss_buffer_t input_token,
 623                      gss_OID *actual_mech_type,
 624                      gss_buffer_t output_token,
 625                      OM_uint32 *ret_flags,
 626                      OM_uint32 *time_rec)
 627 {
 628     OM_uint32 major;
 629     OM_uint32 tmpMajor, tmpMinor;
 630     gss_ctx_id_t ctx = *context_handle;
 631     struct gss_eap_initiator_sm *sm = NULL;
 632     gss_buffer_desc innerInputToken;
 633     gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
 634     enum gss_eap_token_type tokType;
 635     gss_cred_id_t defaultCred = GSS_C_NO_CREDENTIAL;
 636
 637     *minor = 0;
 638
 639     output_token->length = 0;
 640     output_token->value = NULL;
 641
 642     if (ctx == GSS_C_NO_CONTEXT) {
 643         if (input_token != GSS_C_NO_BUFFER && input_token->length != 0) {
 644             return GSS_S_DEFECTIVE_TOKEN;
 645         }
 646
 647         major = gssEapAllocContext(minor, &ctx);
 648         if (GSS_ERROR(major))
 649             goto cleanup;
 650
 651         ctx->flags |= CTX_FLAG_INITIATOR;
 652
 653 #ifdef GSSEAP_ENABLE_REAUTH
 654         if (canReauthP(cred))
 655             ctx->state = EAP_STATE_KRB_REAUTH_GSS;
 656 #endif
 657
 658         *context_handle = ctx;
 659     }
 660
 661     if (cred != GSS_C_NO_CREDENTIAL) {
 662         if ((cred->flags & CRED_FLAG_INITIATE) == 0) {
 663             major = GSS_S_NO_CRED;
 664             goto cleanup;
 665         }
 666     } else {
 667         if (ctx->initiatorCtx.defaultCred == GSS_C_NO_CREDENTIAL) {
 668             major = gssEapAcquireCred(minor,
 669                                       GSS_C_NO_NAME,
 670                                       GSS_C_NO_BUFFER,
 671                                       time_req,
 672                                       GSS_C_NO_OID_SET,
 673                                       GSS_C_INITIATE,
 674                                       &defaultCred,
 675                                       NULL,
 676                                       NULL);
 677             if (GSS_ERROR(major))
 678                 goto cleanup;
 679         }
 680
 681         cred = ctx->initiatorCtx.defaultCred;
 682     }
 683
 684     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 685
 686     sm = &eapGssInitiatorSm[ctx->state];
 687
 688     if (input_token != GSS_C_NO_BUFFER) {
 689         major = gssEapVerifyToken(minor, ctx, input_token,
 690                                   &tokType, &innerInputToken);
 691         if (GSS_ERROR(major))
 692             goto cleanup;
 693
 694         if (tokType != sm->inputTokenType) {
 695             major = GSS_S_DEFECTIVE_TOKEN;
 696             goto cleanup;
 697         }
 698     } else {
 699         innerInputToken.length = 0;
 700         innerInputToken.value = NULL;
 701     }
 702
 703     /*
 704      * Advance through state machine whilst empty tokens are emitted and
 705      * the status is not GSS_S_COMPLETE or an error status.
 706      */
 707     do {
 708         sm = &eapGssInitiatorSm[ctx->state];
 709
 710         major = (sm->processToken)(minor,
 711                                    cred,
 712                                    ctx,
 713                                    target_name,
 714                                    mech_type,
 715                                    req_flags,
 716                                    time_req,
 717                                    input_chan_bindings,
 718                                    &innerInputToken,
 719                                    &innerOutputToken);
 720         if (GSS_ERROR(major))
 721             goto cleanup;
 722     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.value == NULL);
 723
 724     if (actual_mech_type != NULL) {
 725         if (!gssEapInternalizeOid(ctx->mechanismUsed, actual_mech_type))
 726             duplicateOid(&tmpMinor, ctx->mechanismUsed, actual_mech_type);
 727     }
 728     if (innerOutputToken.value != NULL) {
 729         tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
 730                                    sm->outputTokenType, output_token);
 731         if (GSS_ERROR(tmpMajor)) {
 732             major = tmpMajor;
 733             *minor = tmpMinor;
 734             goto cleanup;
 735         }
 736     }
 737     if (ret_flags != NULL)
 738         *ret_flags = ctx->gssFlags;
 739     if (time_rec != NULL)
 740         gssEapContextTime(&tmpMinor, ctx, time_rec);
 741
 742     assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 743
 744 cleanup:
 745     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 746
 747     if (GSS_ERROR(major))
 748         gssEapReleaseContext(&tmpMinor, context_handle);
 749
 750     gss_release_buffer(&tmpMinor, &innerOutputToken);
 751
 752     return major;
 753 }
 754
 755 #ifdef GSSEAP_ENABLE_REAUTH
 756 static int
 757 canReauthP(gss_cred_id_t cred)
 758 {
 759     return (cred != GSS_C_NO_CREDENTIAL &&
 760             cred->krbCred != GSS_C_NO_CREDENTIAL &&
 761             cred->expiryTime > time(NULL));
 762 }
 763
 764 static OM_uint32
 765 eapGssSmInitGssReauth(OM_uint32 *minor,
 766                       gss_cred_id_t cred,
 767                       gss_ctx_id_t ctx,
 768                       gss_name_t target,
 769                       gss_OID mech,
 770                       OM_uint32 reqFlags,
 771                       OM_uint32 timeReq,
 772                       gss_channel_bindings_t chanBindings,
 773                       gss_buffer_t inputToken,
 774                       gss_buffer_t outputToken)
 775 {
 776     OM_uint32 major, tmpMinor;
 777     gss_name_t mechTarget = GSS_C_NO_NAME;
 778     gss_OID actualMech = GSS_C_NO_OID;
 779     OM_uint32 gssFlags, timeRec;
 780
 781     assert(cred != GSS_C_NO_CREDENTIAL);
 782
 783     ctx->flags |= CTX_FLAG_KRB_REAUTH_GSS;
 784
 785     if (inputToken->length == 0) {
 786         major = initBegin(minor, cred, ctx, target, mech,
 787                           reqFlags, timeReq, chanBindings,
 788                           inputToken, outputToken);
 789         if (GSS_ERROR(major))
 790             goto cleanup;
 791     }
 792
 793     major = gssEapMechToGlueName(minor, target, &mechTarget);
 794     if (GSS_ERROR(major))
 795         goto cleanup;
 796
 797     major = gssInitSecContext(minor,
 798                               cred->krbCred,
 799                               &ctx->kerberosCtx,
 800                               mechTarget,
 801                               (gss_OID)gss_mech_krb5,
 802                               reqFlags, /* | GSS_C_DCE_STYLE, */
 803                               timeReq,
 804                               chanBindings,
 805                               inputToken,
 806                               &actualMech,
 807                               outputToken,
 808                               &gssFlags,
 809                               &timeRec);
 810     if (GSS_ERROR(major))
 811         goto cleanup;
 812
 813     ctx->gssFlags = gssFlags;
 814
 815     if (major == GSS_S_COMPLETE) {
 816         major = gssEapReauthComplete(minor, ctx, cred, actualMech, timeRec);
 817         if (GSS_ERROR(major))
 818             goto cleanup;
 819         ctx->state = EAP_STATE_ESTABLISHED;
 820     }
 821
 822 cleanup:
 823     gssReleaseName(&tmpMinor, &mechTarget);
 824
 825     return major;
 826 }
 827 #endif /* GSSEAP_ENABLE_REAUTH */