accept_sec_context.c

   1 /*
   2  * Copyright (c) 2011, 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     VALUE_PAIR *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) {
  76         nameBuf.length = vp->length;
  77         nameBuf.value = vp->vp_strvalue;
  78     } else {
  79         ctx->gssFlags |= GSS_C_ANON_FLAG;
  80     }
  81
  82     major = gssEapImportName(minor, &nameBuf,
  83                              (ctx->gssFlags & GSS_C_ANON_FLAG) ?
  84                                 GSS_C_NT_ANONYMOUS : GSS_C_NT_USER_NAME,
  85                              &ctx->initiatorName);
  86     if (GSS_ERROR(major))
  87         return major;
  88
  89     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  90                                   PW_MS_MPPE_SEND_KEY, VENDORPEC_MS, &vp);
  91     if (GSS_ERROR(major)) {
  92         *minor = GSSEAP_KEY_UNAVAILABLE;
  93         return GSS_S_UNAVAILABLE;
  94     }
  95
  96     major = gssEapDeriveRfc3961Key(minor,
  97                                    vp->vp_octets,
  98                                    vp->length,
  99                                    ctx->encryptionType,
 100                                    &ctx->rfc3961Key);
 101     if (GSS_ERROR(major))
 102         return major;
 103
 104     major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 105                                        &ctx->checksumType);
 106     if (GSS_ERROR(major))
 107         return major;
 108
 109     major = sequenceInit(minor,
 110                          &ctx->seqState, ctx->recvSeq,
 111                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 112                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 113                          TRUE);
 114     if (GSS_ERROR(major))
 115         return major;
 116
 117     major = gssEapCreateAttrContext(minor, cred, ctx,
 118                                     &ctx->initiatorName->attrCtx,
 119                                     &ctx->expiryTime);
 120     if (GSS_ERROR(major))
 121         return major;
 122
 123     *minor = 0;
 124     return GSS_S_COMPLETE;
 125 }
 126
 127 static OM_uint32
 128 eapGssSmAcceptAcceptorName(OM_uint32 *minor,
 129                            gss_cred_id_t cred,
 130                            gss_ctx_id_t ctx,
 131                            gss_name_t target,
 132                            gss_OID mech,
 133                            OM_uint32 reqFlags,
 134                            OM_uint32 timeReq,
 135                            gss_channel_bindings_t chanBindings,
 136                            gss_buffer_t inputToken,
 137                            gss_buffer_t outputToken,
 138                            OM_uint32 *smFlags)
 139 {
 140     OM_uint32 major;
 141
 142     /* XXX TODO import and validate name from inputToken */
 143
 144     if (ctx->acceptorName != GSS_C_NO_NAME) {
 145         /* Send desired target name to acceptor */
 146         major = gssEapDisplayName(minor, ctx->acceptorName,
 147                                   outputToken, NULL);
 148         if (GSS_ERROR(major))
 149             return major;
 150     }
 151
 152     return GSS_S_CONTINUE_NEEDED;
 153 }
 154
 155 #ifdef GSSEAP_DEBUG
 156 static OM_uint32
 157 eapGssSmAcceptVendorInfo(OM_uint32 *minor,
 158                          gss_cred_id_t cred,
 159                          gss_ctx_id_t ctx,
 160                          gss_name_t target,
 161                          gss_OID mech,
 162                          OM_uint32 reqFlags,
 163                          OM_uint32 timeReq,
 164                          gss_channel_bindings_t chanBindings,
 165                          gss_buffer_t inputToken,
 166                          gss_buffer_t outputToken,
 167                          OM_uint32 *smFlags)
 168 {
 169     fprintf(stderr, "GSS-EAP: vendor: %.*s\n",
 170             (int)inputToken->length, (char *)inputToken->value);
 171
 172     return GSS_S_CONTINUE_NEEDED;
 173 }
 174 #endif
 175
 176
 177 /*
 178  * Emit a identity EAP request to force the initiator (peer) to identify
 179  * itself.
 180  */
 181 static OM_uint32
 182 eapGssSmAcceptIdentity(OM_uint32 *minor,
 183                        gss_cred_id_t cred,
 184                        gss_ctx_id_t ctx,
 185                        gss_name_t target,
 186                        gss_OID mech,
 187                        OM_uint32 reqFlags,
 188                        OM_uint32 timeReq,
 189                        gss_channel_bindings_t chanBindings,
 190                        gss_buffer_t inputToken,
 191                        gss_buffer_t outputToken,
 192                        OM_uint32 *smFlags)
 193 {
 194     OM_uint32 major;
 195     struct wpabuf *reqData;
 196     gss_buffer_desc pktBuffer;
 197
 198     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 199         *minor = GSSEAP_CRED_MECH_MISMATCH;
 200         return GSS_S_BAD_MECH;
 201     }
 202
 203     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
 204         *minor = GSSEAP_WRONG_SIZE;
 205         return GSS_S_DEFECTIVE_TOKEN;
 206     }
 207
 208     reqData = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY, 0,
 209                             EAP_CODE_REQUEST, 0);
 210     if (reqData == NULL) {
 211         *minor = ENOMEM;
 212         return GSS_S_FAILURE;
 213     }
 214
 215     pktBuffer.length = wpabuf_len(reqData);
 216     pktBuffer.value = (void *)wpabuf_head(reqData);
 217
 218     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 219     if (GSS_ERROR(major))
 220         return major;
 221
 222     wpabuf_free(reqData);
 223
 224     GSSEAP_SM_TRANSITION_NEXT(ctx);
 225
 226     *minor = 0;
 227     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 228
 229     return GSS_S_CONTINUE_NEEDED;
 230 }
 231
 232 /*
 233  * Returns TRUE if the input token contains an EAP identity response.
 234  */
 235 static int
 236 isIdentityResponseP(gss_buffer_t inputToken)
 237 {
 238     struct wpabuf respData;
 239
 240     wpabuf_set(&respData, inputToken->value, inputToken->length);
 241
 242     return (eap_get_type(&respData) == EAP_TYPE_IDENTITY);
 243 }
 244
 245 /*
 246  * Save the asserted initiator identity from the EAP identity response.
 247  */
 248 static OM_uint32
 249 importInitiatorIdentity(OM_uint32 *minor,
 250                         gss_ctx_id_t ctx,
 251                         gss_buffer_t inputToken)
 252 {
 253     OM_uint32 tmpMinor;
 254     struct wpabuf respData;
 255     const unsigned char *pos;
 256     size_t len;
 257     gss_buffer_desc nameBuf;
 258
 259     wpabuf_set(&respData, inputToken->value, inputToken->length);
 260
 261     pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY,
 262                            &respData, &len);
 263     if (pos == NULL) {
 264         *minor = GSSEAP_PEER_BAD_MESSAGE;
 265         return GSS_S_DEFECTIVE_TOKEN;
 266     }
 267
 268     nameBuf.value = (void *)pos;
 269     nameBuf.length = len;
 270
 271     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
 272
 273     return gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
 274                             &ctx->initiatorName);
 275 }
 276
 277 /*
 278  * Pass the asserted initiator identity to the authentication server.
 279  */
 280 static OM_uint32
 281 setInitiatorIdentity(OM_uint32 *minor,
 282                      gss_ctx_id_t ctx,
 283                      VALUE_PAIR **vps)
 284 {
 285     OM_uint32 major, tmpMinor;
 286     gss_buffer_desc nameBuf;
 287
 288     /*
 289      * We should have got an EAP identity response, but if we didn't, then
 290      * we will just avoid sending User-Name. Note that radsecproxy requires
 291      * User-Name to be sent on every request (presumably so it can remain
 292      * stateless).
 293      */
 294     if (ctx->initiatorName != GSS_C_NO_NAME) {
 295         major = gssEapDisplayName(minor, ctx->initiatorName, &nameBuf, NULL);
 296         if (GSS_ERROR(major))
 297             return major;
 298
 299         major = gssEapRadiusAddAvp(minor, vps, PW_USER_NAME, 0, &nameBuf);
 300         if (GSS_ERROR(major))
 301             return major;
 302
 303         gss_release_buffer(&tmpMinor, &nameBuf);
 304     }
 305
 306     *minor = 0;
 307     return GSS_S_COMPLETE;
 308 }
 309
 310 /*
 311  * Pass the asserted acceptor identity to the authentication server.
 312  */
 313 static OM_uint32
 314 setAcceptorIdentity(OM_uint32 *minor,
 315                     gss_ctx_id_t ctx,
 316                     VALUE_PAIR **vps)
 317 {
 318     OM_uint32 major;
 319     gss_buffer_desc nameBuf;
 320     krb5_context krbContext = NULL;
 321     krb5_principal krbPrinc;
 322     struct rs_context *rc = ctx->acceptorCtx.radContext;
 323
 324     assert(rc != NULL);
 325
 326     if (ctx->acceptorName == GSS_C_NO_NAME) {
 327         *minor = 0;
 328         return GSS_S_COMPLETE;
 329     }
 330
 331     if ((ctx->acceptorName->flags & NAME_FLAG_SERVICE) == 0) {
 332         *minor = GSSEAP_BAD_SERVICE_NAME;
 333         return GSS_S_BAD_NAME;
 334     }
 335
 336     GSSEAP_KRB_INIT(&krbContext);
 337
 338     krbPrinc = ctx->acceptorName->krbPrincipal;
 339     assert(krbPrinc != NULL);
 340     assert(KRB_PRINC_LENGTH(krbPrinc) >= 2);
 341
 342     /* Acceptor-Service-Name */
 343     krbPrincComponentToGssBuffer(krbPrinc, 0, &nameBuf);
 344
 345     major = gssEapRadiusAddAvp(minor, vps,
 346                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 347                                VENDORPEC_UKERNA,
 348                                &nameBuf);
 349     if (GSS_ERROR(major))
 350         return major;
 351
 352     /* Acceptor-Host-Name */
 353     krbPrincComponentToGssBuffer(krbPrinc, 1, &nameBuf);
 354
 355     major = gssEapRadiusAddAvp(minor, vps,
 356                                PW_GSS_ACCEPTOR_HOST_NAME,
 357                                VENDORPEC_UKERNA,
 358                                &nameBuf);
 359     if (GSS_ERROR(major))
 360         return major;
 361
 362     if (KRB_PRINC_LENGTH(krbPrinc) > 2) {
 363         /* Acceptor-Service-Specific */
 364         krb5_principal_data ssiPrinc = *krbPrinc;
 365         char *ssi;
 366
 367         KRB_PRINC_LENGTH(&ssiPrinc) -= 2;
 368         KRB_PRINC_NAME(&ssiPrinc) += 2;
 369
 370         *minor = krb5_unparse_name_flags(krbContext, &ssiPrinc,
 371                                          KRB5_PRINCIPAL_UNPARSE_NO_REALM, &ssi);
 372         if (*minor != 0)
 373             return GSS_S_FAILURE;
 374
 375         nameBuf.value = ssi;
 376         nameBuf.length = strlen(ssi);
 377
 378         major = gssEapRadiusAddAvp(minor, vps,
 379                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFIC,
 380                                    VENDORPEC_UKERNA,
 381                                    &nameBuf);
 382
 383         if (GSS_ERROR(major)) {
 384             krb5_free_unparsed_name(krbContext, ssi);
 385             return major;
 386         }
 387         krb5_free_unparsed_name(krbContext, ssi);
 388     }
 389
 390     krbPrincRealmToGssBuffer(krbPrinc, &nameBuf);
 391     if (nameBuf.length != 0) {
 392         /* Acceptor-Realm-Name */
 393         major = gssEapRadiusAddAvp(minor, vps,
 394                                    PW_GSS_ACCEPTOR_REALM_NAME,
 395                                    VENDORPEC_UKERNA,
 396                                    &nameBuf);
 397         if (GSS_ERROR(major))
 398             return major;
 399     }
 400
 401     *minor = 0;
 402     return GSS_S_COMPLETE;
 403 }
 404
 405 /*
 406  * Allocate a RadSec handle
 407  */
 408 static OM_uint32
 409 createRadiusHandle(OM_uint32 *minor,
 410                    gss_cred_id_t cred,
 411                    gss_ctx_id_t ctx)
 412 {
 413     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 414     const char *configFile = RS_CONFIG_FILE;
 415     const char *configStanza = "gss-eap";
 416     struct rs_alloc_scheme ralloc;
 417     struct rs_error *err;
 418
 419     assert(actx->radContext == NULL);
 420     assert(actx->radConn == NULL);
 421
 422     if (rs_context_create(&actx->radContext, RS_DICT_FILE) != 0) {
 423         *minor = GSSEAP_RADSEC_CONTEXT_FAILURE;
 424         return GSS_S_FAILURE;
 425     }
 426
 427     if (cred->radiusConfigFile != NULL)
 428         configFile = cred->radiusConfigFile;
 429     if (cred->radiusConfigStanza != NULL)
 430         configStanza = cred->radiusConfigStanza;
 431
 432     ralloc.calloc  = GSSEAP_CALLOC;
 433     ralloc.malloc  = GSSEAP_MALLOC;
 434     ralloc.free    = GSSEAP_FREE;
 435     ralloc.realloc = GSSEAP_REALLOC;
 436
 437     rs_context_set_alloc_scheme(actx->radContext, &ralloc);
 438
 439     if (rs_context_read_config(actx->radContext, configFile) != 0) {
 440         err = rs_err_ctx_pop(actx->radContext);
 441         goto fail;
 442     }
 443
 444     if (rs_conn_create(actx->radContext, &actx->radConn, configStanza) != 0) {
 445         err = rs_err_conn_pop(actx->radConn);
 446         goto fail;
 447     }
 448
 449     if (actx->radServer != NULL) {
 450         if (rs_conn_select_peer(actx->radConn, actx->radServer) != 0) {
 451             err = rs_err_conn_pop(actx->radConn);
 452             goto fail;
 453         }
 454     }
 455
 456     *minor = 0;
 457     return GSS_S_COMPLETE;
 458
 459 fail:
 460     return gssEapRadiusMapError(minor, err);
 461 }
 462
 463 /*
 464  * Process a EAP response from the initiator.
 465  */
 466 static OM_uint32
 467 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 468                            gss_cred_id_t cred,
 469                            gss_ctx_id_t ctx,
 470                            gss_name_t target,
 471                            gss_OID mech,
 472                            OM_uint32 reqFlags,
 473                            OM_uint32 timeReq,
 474                            gss_channel_bindings_t chanBindings,
 475                            gss_buffer_t inputToken,
 476                            gss_buffer_t outputToken,
 477                            OM_uint32 *smFlags)
 478 {
 479     OM_uint32 major, tmpMinor;
 480     struct rs_connection *rconn;
 481     struct rs_request *request = NULL;
 482     struct rs_packet *req = NULL, *resp = NULL;
 483     struct radius_packet *frreq, *frresp;
 484
 485     if (ctx->acceptorCtx.radContext == NULL) {
 486         /* May be NULL from an imported partial context */
 487         major = createRadiusHandle(minor, cred, ctx);
 488         if (GSS_ERROR(major))
 489             goto cleanup;
 490     }
 491
 492     if (isIdentityResponseP(inputToken)) {
 493         major = importInitiatorIdentity(minor, ctx, inputToken);
 494         if (GSS_ERROR(major))
 495             return major;
 496     }
 497
 498     rconn = ctx->acceptorCtx.radConn;
 499
 500     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 501         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 502         goto cleanup;
 503     }
 504     frreq = rs_packet_frpkt(req);
 505
 506     major = setInitiatorIdentity(minor, ctx, &frreq->vps);
 507     if (GSS_ERROR(major))
 508         goto cleanup;
 509
 510     major = setAcceptorIdentity(minor, ctx, &frreq->vps);
 511     if (GSS_ERROR(major))
 512         goto cleanup;
 513
 514     major = gssEapRadiusAddAvp(minor, &frreq->vps,
 515                                PW_EAP_MESSAGE, 0, inputToken);
 516     if (GSS_ERROR(major))
 517         goto cleanup;
 518
 519     if (ctx->acceptorCtx.state.length != 0) {
 520         major = gssEapRadiusAddAvp(minor, &frreq->vps, PW_STATE, 0,
 521                                    &ctx->acceptorCtx.state);
 522         if (GSS_ERROR(major))
 523             goto cleanup;
 524
 525         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 526     }
 527
 528     if (rs_request_create(rconn, &request) != 0) {
 529         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 530         goto cleanup;
 531     }
 532
 533     rs_request_add_reqpkt(request, req);
 534     req = NULL;
 535
 536     if (rs_request_send(request, &resp) != 0) {
 537         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 538         goto cleanup;
 539     }
 540
 541     assert(resp != NULL);
 542
 543     frresp = rs_packet_frpkt(resp);
 544     switch (frresp->code) {
 545     case PW_ACCESS_CHALLENGE:
 546     case PW_AUTHENTICATION_ACK:
 547         break;
 548     case PW_AUTHENTICATION_REJECT:
 549         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 550         major = GSS_S_DEFECTIVE_CREDENTIAL;
 551         goto cleanup;
 552         break;
 553     default:
 554         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 555         major = GSS_S_FAILURE;
 556         goto cleanup;
 557         break;
 558     }
 559
 560     major = gssEapRadiusGetAvp(minor, frresp->vps, PW_EAP_MESSAGE, 0,
 561                                outputToken, TRUE);
 562     if (major == GSS_S_UNAVAILABLE && frresp->code == PW_ACCESS_CHALLENGE) {
 563         *minor = GSSEAP_MISSING_EAP_REQUEST;
 564         major = GSS_S_DEFECTIVE_TOKEN;
 565         goto cleanup;
 566     } else if (GSS_ERROR(major))
 567         goto cleanup;
 568
 569     if (frresp->code == PW_ACCESS_CHALLENGE) {
 570         major = gssEapRadiusGetAvp(minor, frresp->vps, PW_STATE, 0,
 571                                    &ctx->acceptorCtx.state, TRUE);
 572         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 573             goto cleanup;
 574     } else {
 575         ctx->acceptorCtx.vps = frresp->vps;
 576         frresp->vps = NULL;
 577
 578         major = acceptReadyEap(minor, ctx, cred);
 579         if (GSS_ERROR(major))
 580             goto cleanup;
 581
 582         GSSEAP_SM_TRANSITION_NEXT(ctx);
 583     }
 584
 585     major = GSS_S_CONTINUE_NEEDED;
 586     *minor = 0;
 587     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 588
 589 cleanup:
 590     if (request != NULL)
 591         rs_request_destroy(request);
 592     if (req != NULL)
 593         rs_packet_destroy(req);
 594     if (resp != NULL)
 595         rs_packet_destroy(resp);
 596     if (GSSEAP_SM_STATE(ctx) == GSSEAP_STATE_INITIATOR_EXTS) {
 597         assert(major == GSS_S_CONTINUE_NEEDED);
 598
 599         rs_conn_destroy(ctx->acceptorCtx.radConn);
 600         ctx->acceptorCtx.radConn = NULL;
 601     }
 602
 603     return major;
 604 }
 605
 606 static OM_uint32
 607 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 608                                  gss_cred_id_t cred,
 609                                  gss_ctx_id_t ctx,
 610                                  gss_name_t target,
 611                                  gss_OID mech,
 612                                  OM_uint32 reqFlags,
 613                                  OM_uint32 timeReq,
 614                                  gss_channel_bindings_t chanBindings,
 615                                  gss_buffer_t inputToken,
 616                                  gss_buffer_t outputToken,
 617                                  OM_uint32 *smFlags)
 618 {
 619     OM_uint32 major, tmpMinor;
 620     gss_iov_buffer_desc iov[2];
 621
 622     iov[0].type = GSS_IOV_BUFFER_TYPE_DATA | GSS_IOV_BUFFER_FLAG_ALLOCATE;
 623     iov[0].buffer.length = 0;
 624     iov[0].buffer.value = NULL;
 625
 626     iov[1].type = GSS_IOV_BUFFER_TYPE_STREAM;
 627     iov[1].buffer = *inputToken;
 628
 629     major = gssEapUnwrapOrVerifyMIC(minor, ctx, NULL, NULL,
 630                                     iov, 2, TOK_TYPE_WRAP);
 631     if (GSS_ERROR(major))
 632         return major;
 633
 634     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS &&
 635         !bufferEqual(&iov[0].buffer, &chanBindings->application_data)) {
 636         major = GSS_S_BAD_BINDINGS;
 637         *minor = GSSEAP_BINDINGS_MISMATCH;
 638     } else {
 639         major = GSS_S_CONTINUE_NEEDED;
 640         *minor = 0;
 641     }
 642
 643     gss_release_buffer(&tmpMinor, &iov[0].buffer);
 644
 645     return major;
 646 }
 647
 648 #ifdef GSSEAP_ENABLE_REAUTH
 649 static OM_uint32
 650 eapGssSmAcceptReauthCreds(OM_uint32 *minor,
 651                           gss_cred_id_t cred,
 652                           gss_ctx_id_t ctx,
 653                           gss_name_t target,
 654                           gss_OID mech,
 655                           OM_uint32 reqFlags,
 656                           OM_uint32 timeReq,
 657                           gss_channel_bindings_t chanBindings,
 658                           gss_buffer_t inputToken,
 659                           gss_buffer_t outputToken,
 660                           OM_uint32 *smFlags)
 661 {
 662     OM_uint32 major;
 663
 664     /*
 665      * If we're built with fast reauthentication enabled, then
 666      * fabricate a ticket from the initiator to ourselves.
 667      */
 668     major = gssEapMakeReauthCreds(minor, ctx, cred, outputToken);
 669     if (major == GSS_S_UNAVAILABLE)
 670         major = GSS_S_COMPLETE;
 671     if (major == GSS_S_COMPLETE)
 672         major = GSS_S_CONTINUE_NEEDED;
 673
 674     return major;
 675 }
 676 #endif
 677
 678 static OM_uint32
 679 eapGssSmAcceptCompleteInitiatorExts(OM_uint32 *minor,
 680                                     gss_cred_id_t cred,
 681                                     gss_ctx_id_t ctx,
 682                                     gss_name_t target,
 683                                     gss_OID mech,
 684                                     OM_uint32 reqFlags,
 685                                     OM_uint32 timeReq,
 686                                     gss_channel_bindings_t chanBindings,
 687                                     gss_buffer_t inputToken,
 688                                     gss_buffer_t outputToken,
 689                                     OM_uint32 *smFlags)
 690 {
 691     GSSEAP_SM_TRANSITION_NEXT(ctx);
 692
 693     *minor = 0;
 694
 695     return GSS_S_CONTINUE_NEEDED;
 696 }
 697
 698 static OM_uint32
 699 eapGssSmAcceptCompleteAcceptorExts(OM_uint32 *minor,
 700                                    gss_cred_id_t cred,
 701                                    gss_ctx_id_t ctx,
 702                                    gss_name_t target,
 703                                    gss_OID mech,
 704                                    OM_uint32 reqFlags,
 705                                    OM_uint32 timeReq,
 706                                    gss_channel_bindings_t chanBindings,
 707                                    gss_buffer_t inputToken,
 708                                    gss_buffer_t outputToken,
 709                                    OM_uint32 *smFlags)
 710 {
 711     GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 712
 713     *minor = 0;
 714     *smFlags |= SM_FLAG_FORCE_SEND_TOKEN;
 715
 716     return GSS_S_COMPLETE;
 717 }
 718
 719 static struct gss_eap_sm eapGssAcceptorSm[] = {
 720     {
 721         ITOK_TYPE_ACCEPTOR_NAME_REQ,
 722         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 723         GSSEAP_STATE_INITIAL,
 724         0,
 725         eapGssSmAcceptAcceptorName
 726     },
 727 #ifdef GSSEAP_DEBUG
 728     {
 729         ITOK_TYPE_VENDOR_INFO,
 730         ITOK_TYPE_NONE,
 731         GSSEAP_STATE_INITIAL,
 732         0,
 733         eapGssSmAcceptVendorInfo,
 734     },
 735 #endif
 736 #ifdef GSSEAP_ENABLE_REAUTH
 737     {
 738         ITOK_TYPE_REAUTH_REQ,
 739         ITOK_TYPE_REAUTH_RESP,
 740         GSSEAP_STATE_INITIAL,
 741         0,
 742         eapGssSmAcceptGssReauth,
 743     },
 744 #endif
 745     {
 746         ITOK_TYPE_NONE,
 747         ITOK_TYPE_EAP_REQ,
 748         GSSEAP_STATE_INITIAL,
 749         SM_ITOK_FLAG_REQUIRED,
 750         eapGssSmAcceptIdentity,
 751     },
 752     {
 753         ITOK_TYPE_EAP_RESP,
 754         ITOK_TYPE_EAP_REQ,
 755         GSSEAP_STATE_AUTHENTICATE,
 756         SM_ITOK_FLAG_REQUIRED,
 757         eapGssSmAcceptAuthenticate
 758     },
 759     {
 760         ITOK_TYPE_GSS_CHANNEL_BINDINGS,
 761         ITOK_TYPE_NONE,
 762         GSSEAP_STATE_INITIATOR_EXTS,
 763         SM_ITOK_FLAG_REQUIRED,
 764         eapGssSmAcceptGssChannelBindings,
 765     },
 766     {
 767         ITOK_TYPE_NONE,
 768         ITOK_TYPE_NONE,
 769         GSSEAP_STATE_INITIATOR_EXTS,
 770         0,
 771         eapGssSmAcceptCompleteInitiatorExts,
 772     },
 773 #ifdef GSSEAP_ENABLE_REAUTH
 774     {
 775         ITOK_TYPE_NONE,
 776         ITOK_TYPE_REAUTH_CREDS,
 777         GSSEAP_STATE_ACCEPTOR_EXTS,
 778         0,
 779         eapGssSmAcceptReauthCreds,
 780     },
 781 #endif
 782     {
 783         ITOK_TYPE_NONE,
 784         ITOK_TYPE_NONE,
 785         GSSEAP_STATE_ACCEPTOR_EXTS,
 786         0,
 787         eapGssSmAcceptCompleteAcceptorExts
 788     },
 789 };
 790
 791 OM_uint32
 792 gss_accept_sec_context(OM_uint32 *minor,
 793                        gss_ctx_id_t *context_handle,
 794                        gss_cred_id_t cred,
 795                        gss_buffer_t input_token,
 796                        gss_channel_bindings_t input_chan_bindings,
 797                        gss_name_t *src_name,
 798                        gss_OID *mech_type,
 799                        gss_buffer_t output_token,
 800                        OM_uint32 *ret_flags,
 801                        OM_uint32 *time_rec,
 802                        gss_cred_id_t *delegated_cred_handle)
 803 {
 804     OM_uint32 major, tmpMinor;
 805     gss_ctx_id_t ctx = *context_handle;
 806
 807     *minor = 0;
 808
 809     output_token->length = 0;
 810     output_token->value = NULL;
 811
 812     if (src_name != NULL)
 813         *src_name = GSS_C_NO_NAME;
 814
 815     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 816         *minor = GSSEAP_TOK_TRUNC;
 817         return GSS_S_DEFECTIVE_TOKEN;
 818     }
 819
 820     if (ctx == GSS_C_NO_CONTEXT) {
 821         major = gssEapAllocContext(minor, &ctx);
 822         if (GSS_ERROR(major))
 823             return major;
 824
 825         *context_handle = ctx;
 826     }
 827
 828     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 829
 830     if (cred == GSS_C_NO_CREDENTIAL) {
 831         if (ctx->defaultCred == GSS_C_NO_CREDENTIAL) {
 832             major = gssEapAcquireCred(minor,
 833                                       GSS_C_NO_NAME,
 834                                       GSS_C_NO_BUFFER,
 835                                       GSS_C_INDEFINITE,
 836                                       GSS_C_NO_OID_SET,
 837                                       GSS_C_ACCEPT,
 838                                       &ctx->defaultCred,
 839                                       NULL,
 840                                       NULL);
 841             if (GSS_ERROR(major))
 842                 goto cleanup;
 843         }
 844
 845         cred = ctx->defaultCred;
 846     }
 847
 848     GSSEAP_MUTEX_LOCK(&cred->mutex);
 849
 850     if (cred->name != GSS_C_NO_NAME) {
 851         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 852         if (GSS_ERROR(major))
 853             goto cleanup;
 854     }
 855
 856     major = gssEapSmStep(minor,
 857                          cred,
 858                          ctx,
 859                          GSS_C_NO_NAME,
 860                          GSS_C_NO_OID,
 861                          0,
 862                          GSS_C_INDEFINITE,
 863                          input_chan_bindings,
 864                          input_token,
 865                          output_token,
 866                          eapGssAcceptorSm,
 867                          sizeof(eapGssAcceptorSm) / sizeof(eapGssAcceptorSm[0]));
 868     if (GSS_ERROR(major))
 869         goto cleanup;
 870
 871     if (mech_type != NULL) {
 872         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 873             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 874     }
 875     if (ret_flags != NULL)
 876         *ret_flags = ctx->gssFlags;
 877     if (delegated_cred_handle != NULL)
 878         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 879
 880     if (major == GSS_S_COMPLETE) {
 881         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 882             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
 883             if (GSS_ERROR(major))
 884                 goto cleanup;
 885         }
 886         if (time_rec != NULL) {
 887             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
 888             if (GSS_ERROR(major))
 889                 goto cleanup;
 890         }
 891     }
 892
 893     assert(CTX_IS_ESTABLISHED(ctx) || major == GSS_S_CONTINUE_NEEDED);
 894
 895 cleanup:
 896     if (cred != GSS_C_NO_CREDENTIAL)
 897         GSSEAP_MUTEX_UNLOCK(&cred->mutex);
 898     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 899
 900     if (GSS_ERROR(major))
 901         gssEapReleaseContext(&tmpMinor, context_handle);
 902
 903     return major;
 904 }
 905
 906 #ifdef GSSEAP_ENABLE_REAUTH
 907 static OM_uint32
 908 acceptReadyKrb(OM_uint32 *minor,
 909                gss_ctx_id_t ctx,
 910                gss_cred_id_t cred,
 911                const gss_name_t initiator,
 912                const gss_OID mech,
 913                OM_uint32 timeRec)
 914 {
 915     OM_uint32 major;
 916
 917     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
 918     if (GSS_ERROR(major))
 919         return major;
 920
 921     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
 922     if (GSS_ERROR(major))
 923         return major;
 924
 925     *minor = 0;
 926     return GSS_S_COMPLETE;
 927 }
 928
 929 static OM_uint32
 930 eapGssSmAcceptGssReauth(OM_uint32 *minor,
 931                         gss_cred_id_t cred,
 932                         gss_ctx_id_t ctx,
 933                         gss_name_t target,
 934                         gss_OID mech,
 935                         OM_uint32 reqFlags,
 936                         OM_uint32 timeReq,
 937                         gss_channel_bindings_t chanBindings,
 938                         gss_buffer_t inputToken,
 939                         gss_buffer_t outputToken,
 940                         OM_uint32 *smFlags)
 941 {
 942     OM_uint32 major, tmpMinor;
 943     gss_name_t krbInitiator = GSS_C_NO_NAME;
 944     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
 945
 946     /*
 947      * If we're built with fast reauthentication support, it's valid
 948      * for an initiator to send a GSS reauthentication token as its
 949      * initial context token, causing us to short-circuit the state
 950      * machine and process Kerberos GSS messages instead.
 951      */
 952
 953     ctx->flags |= CTX_FLAG_KRB_REAUTH;
 954
 955     major = gssAcceptSecContext(minor,
 956                                 &ctx->kerberosCtx,
 957                                 cred->krbCred,
 958                                 inputToken,
 959                                 chanBindings,
 960                                 &krbInitiator,
 961                                 &mech,
 962                                 outputToken,
 963                                 &gssFlags,
 964                                 &timeRec,
 965                                 NULL);
 966     if (major == GSS_S_COMPLETE) {
 967         major = acceptReadyKrb(minor, ctx, cred,
 968                                krbInitiator, mech, timeRec);
 969         if (major == GSS_S_COMPLETE) {
 970             GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 971         }
 972         ctx->gssFlags = gssFlags;
 973     } else if (GSS_ERROR(major) &&
 974         (*smFlags & SM_FLAG_INPUT_TOKEN_CRITICAL) == 0) {
 975         /* pretend reauthentication attempt never happened */
 976         gssDeleteSecContext(&tmpMinor, &ctx->kerberosCtx, GSS_C_NO_BUFFER);
 977         ctx->flags &= ~(CTX_FLAG_KRB_REAUTH);
 978         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_INITIAL);
 979         major = GSS_S_CONTINUE_NEEDED;
 980     }
 981
 982     gssReleaseName(&tmpMinor, &krbInitiator);
 983
 984     return major;
 985 }
 986 #endif /* GSSEAP_ENABLE_REAUTH */