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_ctx_id_t ctx,
  44                         gss_cred_id_t cred,
  45                         gss_buffer_t inputToken,
  46                         gss_channel_bindings_t chanBindings,
  47                         gss_buffer_t outputToken);
  48 #endif
  49
  50 /*
  51  * Mark an acceptor context as ready for cryptographic operations
  52  */
  53 static OM_uint32
  54 acceptReadyEap(OM_uint32 *minor, gss_ctx_id_t ctx, gss_cred_id_t cred)
  55 {
  56     OM_uint32 major, tmpMinor;
  57     VALUE_PAIR *vp;
  58     gss_buffer_desc nameBuf = GSS_C_EMPTY_BUFFER;
  59
  60     /* Cache encryption type derived from selected mechanism OID */
  61     major = gssEapOidToEnctype(minor, ctx->mechanismUsed,
  62                                &ctx->encryptionType);
  63     if (GSS_ERROR(major))
  64         return major;
  65
  66     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
  67
  68     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  69                                   PW_USER_NAME, 0, &vp);
  70     if (major == GSS_S_COMPLETE) {
  71         nameBuf.length = vp->length;
  72         nameBuf.value = vp->vp_strvalue;
  73     } else {
  74         ctx->gssFlags |= GSS_C_ANON_FLAG;
  75     }
  76
  77     major = gssEapImportName(minor, &nameBuf,
  78                              (ctx->gssFlags & GSS_C_ANON_FLAG) ?
  79                                 GSS_C_NT_ANONYMOUS : GSS_C_NT_USER_NAME,
  80                              &ctx->initiatorName);
  81     if (GSS_ERROR(major))
  82         return major;
  83
  84     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  85                                   PW_MS_MPPE_SEND_KEY, VENDORPEC_MS, &vp);
  86     if (GSS_ERROR(major)) {
  87         *minor = GSSEAP_KEY_UNAVAILABLE;
  88         return GSS_S_UNAVAILABLE;
  89     }
  90
  91     major = gssEapDeriveRfc3961Key(minor,
  92                                    vp->vp_octets,
  93                                    vp->length,
  94                                    ctx->encryptionType,
  95                                    &ctx->rfc3961Key);
  96     if (GSS_ERROR(major))
  97         return major;
  98
  99     major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 100                                        &ctx->checksumType);
 101     if (GSS_ERROR(major))
 102         return major;
 103
 104     major = sequenceInit(minor,
 105                          &ctx->seqState, ctx->recvSeq,
 106                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 107                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 108                          TRUE);
 109     if (GSS_ERROR(major))
 110         return major;
 111
 112     major = gssEapCreateAttrContext(minor, cred, ctx,
 113                                     &ctx->initiatorName->attrCtx,
 114                                     &ctx->expiryTime);
 115     if (GSS_ERROR(major))
 116         return major;
 117
 118     *minor = 0;
 119     return GSS_S_COMPLETE;
 120 }
 121
 122 /*
 123  * Emit a identity EAP request to force the initiator (peer) to identify
 124  * itself.
 125  */
 126 static OM_uint32
 127 eapGssSmAcceptIdentity(OM_uint32 *minor,
 128                        gss_ctx_id_t ctx,
 129                        gss_cred_id_t cred,
 130                        gss_buffer_t inputToken,
 131                        gss_channel_bindings_t chanBindings,
 132                        gss_buffer_t outputToken)
 133 {
 134     OM_uint32 major;
 135     struct wpabuf *reqData;
 136     gss_buffer_desc pktBuffer;
 137
 138     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
 139         *minor = GSSEAP_WRONG_SIZE;
 140         return GSS_S_DEFECTIVE_TOKEN;
 141     }
 142
 143     assert(ctx->acceptorName == GSS_C_NO_NAME);
 144
 145     if (cred->name != GSS_C_NO_NAME) {
 146         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 147         if (GSS_ERROR(major))
 148             return major;
 149     }
 150
 151     reqData = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY, 0,
 152                             EAP_CODE_REQUEST, 0);
 153     if (reqData == NULL) {
 154         *minor = ENOMEM;
 155         return GSS_S_FAILURE;
 156     }
 157
 158     pktBuffer.length = wpabuf_len(reqData);
 159     pktBuffer.value = (void *)wpabuf_head(reqData);
 160
 161     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 162     if (GSS_ERROR(major))
 163         return major;
 164
 165     ctx->state = GSSEAP_STATE_AUTHENTICATE;
 166
 167     wpabuf_free(reqData);
 168
 169     *minor = 0;
 170     return GSS_S_CONTINUE_NEEDED;
 171 }
 172
 173 /*
 174  * Returns TRUE if the input token contains an EAP identity response.
 175  */
 176 static int
 177 isIdentityResponseP(gss_buffer_t inputToken)
 178 {
 179     struct wpabuf respData;
 180
 181     wpabuf_set(&respData, inputToken->value, inputToken->length);
 182
 183     return (eap_get_type(&respData) == EAP_TYPE_IDENTITY);
 184 }
 185
 186 /*
 187  * Save the asserted initiator identity from the EAP identity response.
 188  */
 189 static OM_uint32
 190 importInitiatorIdentity(OM_uint32 *minor,
 191                         gss_ctx_id_t ctx,
 192                         gss_buffer_t inputToken)
 193 {
 194     OM_uint32 tmpMinor;
 195     struct wpabuf respData;
 196     const unsigned char *pos;
 197     size_t len;
 198     gss_buffer_desc nameBuf;
 199
 200     wpabuf_set(&respData, inputToken->value, inputToken->length);
 201
 202     pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY,
 203                            &respData, &len);
 204     if (pos == NULL) {
 205         *minor = GSSEAP_PEER_BAD_MESSAGE;
 206         return GSS_S_DEFECTIVE_TOKEN;
 207     }
 208
 209     nameBuf.value = (void *)pos;
 210     nameBuf.length = len;
 211
 212     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
 213
 214     return gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
 215                             &ctx->initiatorName);
 216 }
 217
 218 /*
 219  * Pass the asserted initiator identity to the authentication server.
 220  */
 221 static OM_uint32
 222 setInitiatorIdentity(OM_uint32 *minor,
 223                      gss_ctx_id_t ctx,
 224                      VALUE_PAIR **vps)
 225 {
 226     OM_uint32 major, tmpMinor;
 227     gss_buffer_desc nameBuf;
 228
 229     /*
 230      * We should have got an EAP identity response, but if we didn't, then
 231      * we will just avoid sending User-Name. Note that radsecproxy requires
 232      * User-Name to be sent on every request (presumably so it can remain
 233      * stateless).
 234      */
 235     if (ctx->initiatorName != GSS_C_NO_NAME) {
 236         major = gssEapDisplayName(minor, ctx->initiatorName, &nameBuf, NULL);
 237         if (GSS_ERROR(major))
 238             return major;
 239
 240         major = gssEapRadiusAddAvp(minor, vps, PW_USER_NAME, 0, &nameBuf);
 241         if (GSS_ERROR(major))
 242             return major;
 243
 244         gss_release_buffer(&tmpMinor, &nameBuf);
 245     }
 246
 247     *minor = 0;
 248     return GSS_S_COMPLETE;
 249 }
 250
 251 /*
 252  * Pass the asserted acceptor identity to the authentication server.
 253  */
 254 static OM_uint32
 255 setAcceptorIdentity(OM_uint32 *minor,
 256                     gss_ctx_id_t ctx,
 257                     VALUE_PAIR **vps)
 258 {
 259     OM_uint32 major;
 260     gss_buffer_desc nameBuf;
 261     krb5_context krbContext = NULL;
 262     krb5_principal krbPrinc;
 263     struct rs_context *rc = ctx->acceptorCtx.radContext;
 264
 265     assert(rc != NULL);
 266
 267     if (ctx->acceptorName == GSS_C_NO_NAME) {
 268         *minor = 0;
 269         return GSS_S_COMPLETE;
 270     }
 271
 272     if ((ctx->acceptorName->flags & NAME_FLAG_SERVICE) == 0) {
 273         *minor = GSSEAP_BAD_SERVICE_NAME;
 274         return GSS_S_BAD_NAME;
 275     }
 276
 277     GSSEAP_KRB_INIT(&krbContext);
 278
 279     krbPrinc = ctx->acceptorName->krbPrincipal;
 280     assert(krbPrinc != NULL);
 281     assert(KRB_PRINC_LENGTH(krbPrinc) >= 2);
 282
 283     /* Acceptor-Service-Name */
 284     krbPrincComponentToGssBuffer(krbPrinc, 0, &nameBuf);
 285
 286     major = gssEapRadiusAddAvp(minor, vps,
 287                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 288                                VENDORPEC_UKERNA,
 289                                &nameBuf);
 290     if (GSS_ERROR(major))
 291         return major;
 292
 293     /* Acceptor-Host-Name */
 294     krbPrincComponentToGssBuffer(krbPrinc, 1, &nameBuf);
 295
 296     major = gssEapRadiusAddAvp(minor, vps,
 297                                PW_GSS_ACCEPTOR_HOST_NAME,
 298                                VENDORPEC_UKERNA,
 299                                &nameBuf);
 300     if (GSS_ERROR(major))
 301         return major;
 302
 303     if (KRB_PRINC_LENGTH(krbPrinc) > 2) {
 304         /* Acceptor-Service-Specific */
 305         krb5_principal_data ssiPrinc = *krbPrinc;
 306         char *ssi;
 307
 308         KRB_PRINC_LENGTH(&ssiPrinc) -= 2;
 309         KRB_PRINC_NAME(&ssiPrinc) += 2;
 310
 311         *minor = krb5_unparse_name_flags(krbContext, &ssiPrinc,
 312                                          KRB5_PRINCIPAL_UNPARSE_NO_REALM, &ssi);
 313         if (*minor != 0)
 314             return GSS_S_FAILURE;
 315
 316         nameBuf.value = ssi;
 317         nameBuf.length = strlen(ssi);
 318
 319         major = gssEapRadiusAddAvp(minor, vps,
 320                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFIC,
 321                                    VENDORPEC_UKERNA,
 322                                    &nameBuf);
 323
 324         if (GSS_ERROR(major)) {
 325             krb5_free_unparsed_name(krbContext, ssi);
 326             return major;
 327         }
 328         krb5_free_unparsed_name(krbContext, ssi);
 329     }
 330
 331     krbPrincRealmToGssBuffer(krbPrinc, &nameBuf);
 332     if (nameBuf.length != 0) {
 333         /* Acceptor-Realm-Name */
 334         major = gssEapRadiusAddAvp(minor, vps,
 335                                    PW_GSS_ACCEPTOR_REALM_NAME,
 336                                    VENDORPEC_UKERNA,
 337                                    &nameBuf);
 338         if (GSS_ERROR(major))
 339             return major;
 340     }
 341
 342     *minor = 0;
 343     return GSS_S_COMPLETE;
 344 }
 345
 346 /*
 347  * Allocate a RadSec handle
 348  */
 349 static OM_uint32
 350 createRadiusHandle(OM_uint32 *minor,
 351                    gss_cred_id_t cred,
 352                    gss_ctx_id_t ctx)
 353 {
 354     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 355     const char *configFile = RS_CONFIG_FILE;
 356     const char *configStanza = "gss-eap";
 357     struct rs_alloc_scheme ralloc;
 358     struct rs_error *err;
 359
 360     assert(actx->radContext == NULL);
 361     assert(actx->radConn == NULL);
 362
 363     if (rs_context_create(&actx->radContext, RS_DICT_FILE) != 0) {
 364         *minor = GSSEAP_RADSEC_CONTEXT_FAILURE;
 365         return GSS_S_FAILURE;
 366     }
 367
 368     if (cred->radiusConfigFile != NULL)
 369         configFile = cred->radiusConfigFile;
 370     if (cred->radiusConfigStanza != NULL)
 371         configStanza = cred->radiusConfigStanza;
 372
 373     ralloc.calloc  = GSSEAP_CALLOC;
 374     ralloc.malloc  = GSSEAP_MALLOC;
 375     ralloc.free    = GSSEAP_FREE;
 376     ralloc.realloc = GSSEAP_REALLOC;
 377
 378     rs_context_set_alloc_scheme(actx->radContext, &ralloc);
 379
 380     if (rs_context_read_config(actx->radContext, configFile) != 0) {
 381         err = rs_err_ctx_pop(actx->radContext);
 382         goto fail;
 383     }
 384
 385     if (rs_conn_create(actx->radContext, &actx->radConn, configStanza) != 0) {
 386         err = rs_err_conn_pop(actx->radConn);
 387         goto fail;
 388     }
 389
 390     if (actx->radServer != NULL) {
 391         if (rs_conn_select_peer(actx->radConn, actx->radServer) != 0) {
 392             err = rs_err_conn_pop(actx->radConn);
 393             goto fail;
 394         }
 395     }
 396
 397     *minor = 0;
 398     return GSS_S_COMPLETE;
 399
 400 fail:
 401     return gssEapRadiusMapError(minor, err);
 402 }
 403
 404 /*
 405  * Process a EAP response from the initiator.
 406  */
 407 static OM_uint32
 408 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 409                            gss_ctx_id_t ctx,
 410                            gss_cred_id_t cred,
 411                            gss_buffer_t inputToken,
 412                            gss_channel_bindings_t chanBindings,
 413                            gss_buffer_t outputToken)
 414 {
 415     OM_uint32 major, tmpMinor;
 416     struct rs_connection *rconn;
 417     struct rs_request *request = NULL;
 418     struct rs_packet *req = NULL, *resp = NULL;
 419     struct radius_packet *frreq, *frresp;
 420
 421     if (ctx->acceptorCtx.radContext == NULL) {
 422         /* May be NULL from an imported partial context */
 423         major = createRadiusHandle(minor, cred, ctx);
 424         if (GSS_ERROR(major))
 425             goto cleanup;
 426     }
 427
 428     if (isIdentityResponseP(inputToken)) {
 429         major = importInitiatorIdentity(minor, ctx, inputToken);
 430         if (GSS_ERROR(major))
 431             return major;
 432     }
 433
 434     rconn = ctx->acceptorCtx.radConn;
 435
 436     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 437         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 438         goto cleanup;
 439     }
 440     frreq = rs_packet_frpkt(req);
 441
 442     major = setInitiatorIdentity(minor, ctx, &frreq->vps);
 443     if (GSS_ERROR(major))
 444         goto cleanup;
 445
 446     major = setAcceptorIdentity(minor, ctx, &frreq->vps);
 447     if (GSS_ERROR(major))
 448         goto cleanup;
 449
 450     major = gssEapRadiusAddAvp(minor, &frreq->vps,
 451                                PW_EAP_MESSAGE, 0, inputToken);
 452     if (GSS_ERROR(major))
 453         goto cleanup;
 454
 455     if (ctx->acceptorCtx.state.length != 0) {
 456         major = gssEapRadiusAddAvp(minor, &frreq->vps, PW_STATE, 0,
 457                                    &ctx->acceptorCtx.state);
 458         if (GSS_ERROR(major))
 459             goto cleanup;
 460
 461         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 462     }
 463
 464     if (rs_request_create(rconn, &request) != 0) {
 465         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 466         goto cleanup;
 467     }
 468
 469     rs_request_add_reqpkt(request, req);
 470     req = NULL;
 471
 472     if (rs_request_send(request, &resp) != 0) {
 473         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 474         goto cleanup;
 475     }
 476
 477     assert(resp != NULL);
 478
 479     frresp = rs_packet_frpkt(resp);
 480     switch (frresp->code) {
 481     case PW_AUTHENTICATION_ACK:
 482     case PW_ACCESS_CHALLENGE:
 483         major = GSS_S_CONTINUE_NEEDED;
 484         break;
 485     case PW_AUTHENTICATION_REJECT:
 486         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 487         major = GSS_S_DEFECTIVE_CREDENTIAL;
 488         goto cleanup;
 489         break;
 490     default:
 491         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 492         major = GSS_S_FAILURE;
 493         goto cleanup;
 494         break;
 495     }
 496
 497     major = gssEapRadiusGetAvp(minor, frresp->vps, PW_EAP_MESSAGE, 0,
 498                                outputToken, TRUE);
 499     if (major == GSS_S_UNAVAILABLE && frresp->code == PW_ACCESS_CHALLENGE) {
 500         *minor = GSSEAP_MISSING_EAP_REQUEST;
 501         major = GSS_S_DEFECTIVE_TOKEN;
 502         goto cleanup;
 503     } else if (GSS_ERROR(major))
 504         goto cleanup;
 505
 506     if (frresp->code == PW_ACCESS_CHALLENGE) {
 507         major = gssEapRadiusGetAvp(minor, frresp->vps, PW_STATE, 0,
 508                                    &ctx->acceptorCtx.state, TRUE);
 509         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 510             goto cleanup;
 511     } else {
 512         ctx->acceptorCtx.vps = frresp->vps;
 513         frresp->vps = NULL;
 514
 515         rs_conn_destroy(ctx->acceptorCtx.radConn);
 516         ctx->acceptorCtx.radConn = NULL;
 517
 518         major = acceptReadyEap(minor, ctx, cred);
 519         if (GSS_ERROR(major))
 520             goto cleanup;
 521
 522         ctx->state = GSSEAP_STATE_EXTENSIONS_REQ;
 523     }
 524
 525     *minor = 0;
 526     major = GSS_S_CONTINUE_NEEDED;
 527
 528 cleanup:
 529     if (request != NULL)
 530         rs_request_destroy(request);
 531     if (req != NULL)
 532         rs_packet_destroy(req);
 533
 534     return major;
 535 }
 536
 537 static OM_uint32
 538 eapGssSmAcceptExtensionsReq(OM_uint32 *minor,
 539                             gss_ctx_id_t ctx,
 540                             gss_cred_id_t cred,
 541                             gss_buffer_t inputToken,
 542                             gss_channel_bindings_t chanBindings,
 543                             gss_buffer_t outputToken)
 544 {
 545     OM_uint32 major;
 546
 547     major = gssEapVerifyExtensions(minor, cred, ctx, chanBindings, inputToken);
 548     if (GSS_ERROR(major))
 549         return major;
 550
 551     outputToken->length = 0;
 552     outputToken->value = NULL;
 553
 554     ctx->state = GSSEAP_STATE_EXTENSIONS_RESP;
 555
 556     *minor = 0;
 557     return GSS_S_CONTINUE_NEEDED;
 558 }
 559
 560 static OM_uint32
 561 eapGssSmAcceptExtensionsResp(OM_uint32 *minor,
 562                              gss_ctx_id_t ctx,
 563                              gss_cred_id_t cred,
 564                              gss_buffer_t inputToken,
 565                              gss_channel_bindings_t chanBindings,
 566                              gss_buffer_t outputToken)
 567 {
 568     OM_uint32 major;
 569
 570     major = gssEapMakeExtensions(minor, cred, ctx, chanBindings, outputToken);
 571     if (GSS_ERROR(major))
 572         return major;
 573
 574     ctx->state = GSSEAP_STATE_ESTABLISHED;
 575
 576     *minor = 0;
 577     return GSS_S_COMPLETE;
 578 }
 579
 580 static OM_uint32
 581 eapGssSmAcceptEstablished(OM_uint32 *minor,
 582                           gss_ctx_id_t ctx,
 583                           gss_cred_id_t cred,
 584                           gss_buffer_t inputToken,
 585                           gss_channel_bindings_t chanBindings,
 586                           gss_buffer_t outputToken)
 587 {
 588     /* Called with already established context */
 589     *minor = GSSEAP_CONTEXT_ESTABLISHED;
 590     return GSS_S_BAD_STATUS;
 591 }
 592
 593 static OM_uint32
 594 makeErrorToken(OM_uint32 *minor,
 595                OM_uint32 majorStatus,
 596                OM_uint32 minorStatus,
 597                gss_buffer_t outputToken)
 598 {
 599     unsigned char errorData[8];
 600     gss_buffer_desc errorBuffer;
 601
 602     assert(GSS_ERROR(majorStatus));
 603
 604     /*
 605      * Only return error codes that the initiator could have caused,
 606      * to avoid information leakage.
 607      */
 608     if (IS_RADIUS_ERROR(minorStatus)) {
 609         /* Squash RADIUS error codes */
 610         minorStatus = GSSEAP_RADIUS_PROT_FAILURE;
 611     } else if (!IS_WIRE_ERROR(minorStatus)) {
 612         /* Don't return non-wire error codes */
 613         return GSS_S_COMPLETE;
 614     }
 615
 616     minorStatus -= ERROR_TABLE_BASE_eapg;
 617
 618     store_uint32_be(majorStatus, &errorData[0]);
 619     store_uint32_be(minorStatus, &errorData[4]);
 620
 621     errorBuffer.length = sizeof(errorData);
 622     errorBuffer.value = errorData;
 623
 624     return duplicateBuffer(minor, &errorBuffer, outputToken);
 625 }
 626
 627 static struct gss_eap_acceptor_sm {
 628     enum gss_eap_token_type inputTokenType;
 629     enum gss_eap_token_type outputTokenType;
 630     OM_uint32 (*processToken)(OM_uint32 *,
 631                               gss_ctx_id_t,
 632                               gss_cred_id_t,
 633                               gss_buffer_t,
 634                               gss_channel_bindings_t,
 635                               gss_buffer_t);
 636 } eapGssAcceptorSm[] = {
 637     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,       eapGssSmAcceptIdentity           },
 638     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,       eapGssSmAcceptAuthenticate       },
 639     { TOK_TYPE_EXT_REQ,     TOK_TYPE_NONE,          eapGssSmAcceptExtensionsReq      },
 640     { TOK_TYPE_NONE,        TOK_TYPE_EXT_RESP,      eapGssSmAcceptExtensionsResp     },
 641     { TOK_TYPE_NONE,        TOK_TYPE_NONE,          eapGssSmAcceptEstablished        },
 642     { TOK_TYPE_NONE,        TOK_TYPE_CONTEXT_ERR,   NULL                             },
 643 #ifdef GSSEAP_ENABLE_REAUTH
 644     { TOK_TYPE_GSS_REAUTH,  TOK_TYPE_GSS_REAUTH,    eapGssSmAcceptGssReauth          },
 645 #endif
 646 };
 647
 648 OM_uint32
 649 gss_accept_sec_context(OM_uint32 *minor,
 650                        gss_ctx_id_t *context_handle,
 651                        gss_cred_id_t cred,
 652                        gss_buffer_t input_token,
 653                        gss_channel_bindings_t input_chan_bindings,
 654                        gss_name_t *src_name,
 655                        gss_OID *mech_type,
 656                        gss_buffer_t output_token,
 657                        OM_uint32 *ret_flags,
 658                        OM_uint32 *time_rec,
 659                        gss_cred_id_t *delegated_cred_handle)
 660 {
 661     OM_uint32 major;
 662     OM_uint32 tmpMajor, tmpMinor;
 663     gss_ctx_id_t ctx = *context_handle;
 664     struct gss_eap_acceptor_sm *sm = NULL;
 665     gss_buffer_desc innerInputToken = GSS_C_EMPTY_BUFFER;
 666     gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
 667     enum gss_eap_token_type tokType;
 668     int initialContextToken = 0;
 669
 670     *minor = 0;
 671
 672     output_token->length = 0;
 673     output_token->value = NULL;
 674
 675     if (src_name != NULL)
 676         *src_name = GSS_C_NO_NAME;
 677
 678     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 679         *minor = GSSEAP_TOK_TRUNC;
 680         return GSS_S_DEFECTIVE_TOKEN;
 681     }
 682
 683     if (ctx == GSS_C_NO_CONTEXT) {
 684         major = gssEapAllocContext(minor, &ctx);
 685         if (GSS_ERROR(major))
 686             return major;
 687
 688         initialContextToken = 1;
 689         *context_handle = ctx;
 690     }
 691
 692     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 693
 694     if (cred == GSS_C_NO_CREDENTIAL) {
 695         if (ctx->defaultCred == GSS_C_NO_CREDENTIAL) {
 696             major = gssEapAcquireCred(minor,
 697                                       GSS_C_NO_NAME,
 698                                       GSS_C_NO_BUFFER,
 699                                       GSS_C_INDEFINITE,
 700                                       GSS_C_NO_OID_SET,
 701                                       GSS_C_ACCEPT,
 702                                       &ctx->defaultCred,
 703                                       NULL,
 704                                       NULL);
 705             if (GSS_ERROR(major))
 706                 goto cleanup;
 707         }
 708
 709         cred = ctx->defaultCred;
 710     }
 711
 712     GSSEAP_MUTEX_LOCK(&cred->mutex);
 713
 714     sm = &eapGssAcceptorSm[ctx->state];
 715
 716     major = gssEapVerifyToken(minor, ctx, input_token,
 717                               &tokType, &innerInputToken);
 718     if (GSS_ERROR(major))
 719         goto cleanup;
 720
 721     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 722         *minor = GSSEAP_CRED_MECH_MISMATCH;
 723         major = GSS_S_BAD_MECH;
 724         goto cleanup;
 725     }
 726
 727 #ifdef GSSEAP_ENABLE_REAUTH
 728     /*
 729      * If we're built with fast reauthentication support, it's valid
 730      * for an initiator to send a GSS reauthentication token as its
 731      * initial context token, causing us to short-circuit the state
 732      * machine and process Kerberos GSS messages instead.
 733      */
 734     if (tokType == TOK_TYPE_GSS_REAUTH && initialContextToken) {
 735         ctx->state = GSSEAP_STATE_KRB_REAUTH;
 736     } else
 737 #endif
 738     if (tokType != sm->inputTokenType) {
 739         *minor = GSSEAP_WRONG_TOK_ID;
 740         major = GSS_S_DEFECTIVE_TOKEN;
 741         goto cleanup;
 742     }
 743
 744     do {
 745         sm = &eapGssAcceptorSm[ctx->state];
 746
 747         major = (sm->processToken)(minor,
 748                                    ctx,
 749                                    cred,
 750                                    &innerInputToken,
 751                                    input_chan_bindings,
 752                                    &innerOutputToken);
 753         if (GSS_ERROR(major)) {
 754             /* Possibly generate an error token */
 755             tmpMajor = makeErrorToken(&tmpMinor, major, *minor, &innerOutputToken);
 756             if (GSS_ERROR(tmpMajor)) {
 757                 major = tmpMajor;
 758                 goto cleanup;
 759             }
 760
 761             sm = &eapGssAcceptorSm[GSSEAP_STATE_ERROR];
 762             goto send_token;
 763         }
 764     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.length == 0);
 765
 766     if (mech_type != NULL) {
 767         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 768             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 769     }
 770     if (ret_flags != NULL)
 771         *ret_flags = ctx->gssFlags;
 772     if (delegated_cred_handle != NULL)
 773         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 774
 775     if (major == GSS_S_COMPLETE) {
 776         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 777             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
 778             if (GSS_ERROR(major))
 779                 goto cleanup;
 780         }
 781         if (time_rec != NULL) {
 782             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
 783             if (GSS_ERROR(major))
 784                 goto cleanup;
 785         }
 786     }
 787
 788     assert(ctx->state == GSSEAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 789
 790 send_token:
 791     if (innerOutputToken.value != NULL) {
 792         tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
 793                                    sm->outputTokenType, output_token);
 794         if (GSS_ERROR(tmpMajor)) {
 795             major = tmpMajor;
 796             *minor = tmpMinor;
 797             goto cleanup;
 798         }
 799     }
 800
 801 cleanup:
 802     if (cred != GSS_C_NO_CREDENTIAL)
 803         GSSEAP_MUTEX_UNLOCK(&cred->mutex);
 804     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 805
 806     if (GSS_ERROR(major))
 807         gssEapReleaseContext(&tmpMinor, context_handle);
 808
 809     gss_release_buffer(&tmpMinor, &innerOutputToken);
 810
 811     return major;
 812 }
 813
 814 #ifdef GSSEAP_ENABLE_REAUTH
 815 static OM_uint32
 816 acceptReadyKrb(OM_uint32 *minor,
 817                gss_ctx_id_t ctx,
 818                gss_cred_id_t cred,
 819                const gss_name_t initiator,
 820                const gss_OID mech,
 821                OM_uint32 timeRec)
 822 {
 823     OM_uint32 major;
 824
 825     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
 826     if (GSS_ERROR(major))
 827         return major;
 828
 829     if (cred->name != GSS_C_NO_NAME) {
 830         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 831         if (GSS_ERROR(major))
 832             return major;
 833     }
 834
 835     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
 836     if (GSS_ERROR(major))
 837         return major;
 838
 839     ctx->state = GSSEAP_STATE_ESTABLISHED;
 840
 841     *minor = 0;
 842     return GSS_S_COMPLETE;
 843 }
 844
 845 static OM_uint32
 846 eapGssSmAcceptGssReauth(OM_uint32 *minor,
 847                         gss_ctx_id_t ctx,
 848                         gss_cred_id_t cred,
 849                         gss_buffer_t inputToken,
 850                         gss_channel_bindings_t chanBindings,
 851                         gss_buffer_t outputToken)
 852 {
 853     OM_uint32 major, tmpMinor;
 854     gss_name_t krbInitiator = GSS_C_NO_NAME;
 855     gss_OID mech = GSS_C_NO_OID;
 856     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
 857
 858     ctx->flags |= CTX_FLAG_KRB_REAUTH;
 859
 860     major = gssAcceptSecContext(minor,
 861                                 &ctx->kerberosCtx,
 862                                 cred->krbCred,
 863                                 inputToken,
 864                                 chanBindings,
 865                                 &krbInitiator,
 866                                 &mech,
 867                                 outputToken,
 868                                 &gssFlags,
 869                                 &timeRec,
 870                                 NULL);
 871     if (major == GSS_S_COMPLETE) {
 872         major = acceptReadyKrb(minor, ctx, cred,
 873                                krbInitiator, mech, timeRec);
 874     }
 875
 876     ctx->gssFlags = gssFlags;
 877
 878     gssReleaseName(&tmpMinor, &krbInitiator);
 879
 880     return major;
 881 }
 882 #endif /* GSSEAP_ENABLE_REAUTH */