accept_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 OM_uint32
  37 eapGssSmAcceptGssReauth(OM_uint32 *minor,
  38                         gss_ctx_id_t ctx,
  39                         gss_cred_id_t cred,
  40                         gss_buffer_t inputToken,
  41                         gss_channel_bindings_t chanBindings,
  42                         gss_buffer_t outputToken);
  43 #endif
  44
  45 /*
  46  * Mark a context as ready for cryptographic operations
  47  */
  48 static OM_uint32
  49 acceptReadyEap(OM_uint32 *minor, gss_ctx_id_t ctx, gss_cred_id_t cred)
  50 {
  51     OM_uint32 major, tmpMinor;
  52     VALUE_PAIR *vp;
  53     gss_buffer_desc nameBuf = GSS_C_EMPTY_BUFFER;
  54
  55     /* Cache encryption type derived from selected mechanism OID */
  56     major = gssEapOidToEnctype(minor, ctx->mechanismUsed,
  57                                &ctx->encryptionType);
  58     if (GSS_ERROR(major))
  59         return major;
  60
  61     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
  62
  63     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  64                                   PW_USER_NAME, 0, &vp);
  65     if (major == GSS_S_COMPLETE) {
  66         nameBuf.length = vp->length;
  67         nameBuf.value = vp->vp_strvalue;
  68     } else {
  69         ctx->gssFlags |= GSS_C_ANON_FLAG;
  70     }
  71
  72     major = gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
  73                              &ctx->initiatorName);
  74     if (GSS_ERROR(major))
  75         return major;
  76
  77     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  78                                   PW_MS_MPPE_SEND_KEY, VENDORPEC_MS, &vp);
  79     if (GSS_ERROR(major)) {
  80         *minor = GSSEAP_KEY_UNAVAILABLE;
  81         return GSS_S_UNAVAILABLE;
  82     }
  83
  84     major = gssEapDeriveRfc3961Key(minor,
  85                                    vp->vp_octets,
  86                                    vp->length,
  87                                    ctx->encryptionType,
  88                                    &ctx->rfc3961Key);
  89     if (GSS_ERROR(major))
  90         return major;
  91
  92     major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
  93                                        &ctx->checksumType);
  94     if (GSS_ERROR(major))
  95         return major;
  96
  97     major = sequenceInit(minor,
  98                          &ctx->seqState, ctx->recvSeq,
  99                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 100                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 101                          TRUE);
 102     if (GSS_ERROR(major))
 103         return major;
 104
 105     ctx->initiatorName->attrCtx = gssEapCreateAttrContext(cred, ctx);
 106
 107     return GSS_S_COMPLETE;
 108 }
 109
 110 static OM_uint32
 111 eapGssSmAcceptIdentity(OM_uint32 *minor,
 112                        gss_ctx_id_t ctx,
 113                        gss_cred_id_t cred,
 114                        gss_buffer_t inputToken,
 115                        gss_channel_bindings_t chanBindings,
 116                        gss_buffer_t outputToken)
 117 {
 118     OM_uint32 major;
 119     union {
 120         struct eap_hdr pdu;
 121         unsigned char data[5];
 122     } pkt;
 123     gss_buffer_desc pktBuffer;
 124
 125     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0)
 126         return GSS_S_DEFECTIVE_TOKEN;
 127
 128     assert(ctx->acceptorName == GSS_C_NO_NAME);
 129
 130     if (cred != GSS_C_NO_CREDENTIAL && cred->name != GSS_C_NO_NAME) {
 131         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 132         if (GSS_ERROR(major))
 133             return major;
 134     }
 135
 136     pkt.pdu.code = EAP_CODE_REQUEST;
 137     pkt.pdu.identifier = 0;
 138     pkt.pdu.length = htons(sizeof(pkt.data));
 139     pkt.data[4] = EAP_TYPE_IDENTITY;
 140
 141     pktBuffer.length = sizeof(pkt.data);
 142     pktBuffer.value = pkt.data;
 143
 144     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 145     if (GSS_ERROR(major))
 146         return major;
 147
 148     ctx->state = EAP_STATE_AUTHENTICATE;
 149
 150     return GSS_S_CONTINUE_NEEDED;
 151 }
 152
 153 static OM_uint32
 154 setAcceptorIdentity(OM_uint32 *minor,
 155                     gss_ctx_id_t ctx,
 156                     VALUE_PAIR **vps)
 157 {
 158     OM_uint32 major;
 159     gss_buffer_desc nameBuf;
 160     krb5_context krbContext = NULL;
 161     krb5_principal krbPrinc;
 162     struct rs_handle *rh = ctx->acceptorCtx.radHandle;
 163
 164     assert(rh != NULL);
 165
 166     /* Awaits further specification */
 167     if (ctx->acceptorName == GSS_C_NO_NAME)
 168         return GSS_S_COMPLETE;
 169
 170     GSSEAP_KRB_INIT(&krbContext);
 171
 172     krbPrinc = ctx->acceptorName->krbPrincipal;
 173     assert(krbPrinc != NULL);
 174
 175     if (krb5_princ_size(krbContext, krbPrinc) < 2)
 176         return GSS_S_BAD_NAME;
 177
 178     /* Acceptor-Service-Name */
 179     krbDataToGssBuffer(krb5_princ_component(krbContext, krbPrinc, 0), &nameBuf);
 180
 181     major = gssEapRadiusAddAvp(minor, vps,
 182                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 183                                VENDORPEC_UKERNA,
 184                                &nameBuf);
 185     if (GSS_ERROR(major))
 186         return major;
 187
 188     /* Acceptor-Host-Name */
 189     krbDataToGssBuffer(krb5_princ_component(krbContext, krbPrinc, 1), &nameBuf);
 190
 191     major = gssEapRadiusAddAvp(minor, vps,
 192                                PW_GSS_ACCEPTOR_HOST_NAME,
 193                                VENDORPEC_UKERNA,
 194                                &nameBuf);
 195     if (GSS_ERROR(major))
 196         return major;
 197
 198     if (krb5_princ_size(krbContext, krbPrinc) > 2) {
 199         /* Acceptor-Service-Specific */
 200         krb5_principal_data ssiPrinc = *krbPrinc;
 201         char *ssi;
 202
 203         krb5_princ_size(krbContext, &ssiPrinc) -= 2;
 204         krb5_princ_name(krbContext, &ssiPrinc) += 2;
 205
 206         *minor = krb5_unparse_name_flags(krbContext, &ssiPrinc,
 207                                          KRB5_PRINCIPAL_UNPARSE_NO_REALM, &ssi);
 208         if (*minor != 0)
 209             return GSS_S_FAILURE;
 210
 211         nameBuf.value = ssi;
 212         nameBuf.length = strlen(ssi);
 213
 214         major = gssEapRadiusAddAvp(minor, vps,
 215                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFIC,
 216                                    VENDORPEC_UKERNA,
 217                                    &nameBuf);
 218
 219         if (GSS_ERROR(major)) {
 220             krb5_free_unparsed_name(krbContext, ssi);
 221             return major;
 222         }
 223         krb5_free_unparsed_name(krbContext, ssi);
 224     }
 225
 226     krbDataToGssBuffer(krb5_princ_realm(krbContext, krbPrinc), &nameBuf);
 227     if (nameBuf.length != 0) {
 228         /* Acceptor-Realm-Name */
 229         major = gssEapRadiusAddAvp(minor, vps,
 230                                    PW_GSS_ACCEPTOR_REALM_NAME,
 231                                    VENDORPEC_UKERNA,
 232                                    &nameBuf);
 233         if (GSS_ERROR(major))
 234             return major;
 235     }
 236
 237     return GSS_S_COMPLETE;
 238 }
 239
 240 static OM_uint32
 241 createRadiusHandle(OM_uint32 *minor,
 242                    gss_cred_id_t cred,
 243                    gss_ctx_id_t ctx)
 244 {
 245     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 246     const char *configFile = RS_CONFIG_FILE;
 247     const char *configStanza = "gss-eap";
 248     struct rs_alloc_scheme ralloc;
 249     struct rs_error *err;
 250
 251     assert(actx->radHandle == NULL);
 252     assert(actx->radConn == NULL);
 253
 254     if (rs_context_create(&actx->radHandle, RS_DICT_FILE) != 0) {
 255         *minor = GSSEAP_RADSEC_INIT_FAILURE;
 256         return GSS_S_FAILURE;
 257     }
 258
 259     if (cred != GSS_C_NO_CREDENTIAL) {
 260         if (cred->radiusConfigFile != NULL)
 261             configFile = cred->radiusConfigFile;
 262         if (cred->radiusConfigStanza != NULL)
 263             configStanza = cred->radiusConfigStanza;
 264     }
 265
 266     ralloc.calloc  = GSSEAP_CALLOC;
 267     ralloc.malloc  = GSSEAP_MALLOC;
 268     ralloc.free    = GSSEAP_FREE;
 269     ralloc.realloc = GSSEAP_REALLOC;
 270
 271     rs_context_set_alloc_scheme(actx->radHandle, &ralloc);
 272
 273     if (rs_context_read_config(actx->radHandle, configFile) != 0) {
 274         err = rs_err_ctx_pop(actx->radHandle);
 275         goto fail;
 276     }
 277
 278     if (rs_conn_create(actx->radHandle, &actx->radConn, configStanza) != 0) {
 279         err = rs_err_conn_pop(actx->radConn);
 280         goto fail;
 281     }
 282
 283     /* XXX TODO rs_conn_select_server does not exist yet */
 284 #if 0
 285     if (actx->radServer != NULL) {
 286         if (rs_conn_select_server(actx->radConn, actx->radServer) != 0) {
 287             err = rs_err_conn_pop(actx->radConn);
 288             goto fail;
 289         }
 290     }
 291 #endif
 292
 293     *minor = 0;
 294     return GSS_S_COMPLETE;
 295
 296 fail:
 297     return gssEapRadiusMapError(minor, err);
 298 }
 299
 300 static OM_uint32
 301 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 302                            gss_ctx_id_t ctx,
 303                            gss_cred_id_t cred,
 304                            gss_buffer_t inputToken,
 305                            gss_channel_bindings_t chanBindings,
 306                            gss_buffer_t outputToken)
 307 {
 308     OM_uint32 major, tmpMinor;
 309     struct rs_handle *rh;
 310     struct rs_connection *rconn;
 311     struct rs_request *request = NULL;
 312     struct rs_packet *req = NULL, *resp = NULL;
 313     struct radius_packet *frreq, *frresp;
 314     int sendAcceptorIdentity = 0;
 315
 316     if (ctx->acceptorCtx.radHandle == NULL) {
 317         /* May be NULL from an imported partial context */
 318         major = createRadiusHandle(minor, cred, ctx);
 319         if (GSS_ERROR(major))
 320             goto cleanup;
 321
 322         sendAcceptorIdentity = 1;
 323     }
 324
 325     rh = ctx->acceptorCtx.radHandle;
 326     rconn = ctx->acceptorCtx.radConn;
 327
 328     if (rs_packet_create_acc_request(rconn, &req, NULL, NULL) != 0) {
 329         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 330         goto cleanup;
 331     }
 332     frreq = rs_packet_frpkt(req);
 333
 334     if (sendAcceptorIdentity) {
 335         major = setAcceptorIdentity(minor, ctx, &frreq->vps);
 336         if (GSS_ERROR(major))
 337             goto cleanup;
 338     }
 339
 340     major = gssEapRadiusAddAvp(minor, &frreq->vps,
 341                                PW_EAP_MESSAGE, 0, inputToken);
 342     if (GSS_ERROR(major))
 343         goto cleanup;
 344
 345     if (ctx->acceptorCtx.state.length != 0) {
 346         major = gssEapRadiusAddAvp(minor, &frreq->vps, PW_STATE, 0,
 347                                    &ctx->acceptorCtx.state);
 348         if (GSS_ERROR(major))
 349             goto cleanup;
 350
 351         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 352     }
 353
 354     if (rs_request_create(rconn, &request) != 0 ||
 355         rs_request_send(request, req, &resp) != 0) {
 356         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 357         goto cleanup;
 358     }
 359
 360     assert(resp != NULL);
 361
 362     frresp = rs_packet_frpkt(resp);
 363     switch (frresp->code) {
 364     case PW_AUTHENTICATION_ACK:
 365     case PW_ACCESS_CHALLENGE:
 366         major = GSS_S_CONTINUE_NEEDED;
 367         break;
 368     case PW_AUTHENTICATION_REJECT:
 369         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 370         major = GSS_S_DEFECTIVE_CREDENTIAL;
 371         goto cleanup;
 372         break;
 373     default:
 374         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 375         major = GSS_S_FAILURE;
 376         goto cleanup;
 377         break;
 378     }
 379
 380     major = gssEapRadiusGetAvp(minor, frresp->vps, PW_EAP_MESSAGE, 0,
 381                                outputToken, TRUE);
 382     if (major == GSS_S_UNAVAILABLE && frresp->code == PW_ACCESS_CHALLENGE) {
 383         *minor = GSSEAP_MISSING_EAP_REQUEST;
 384         major = GSS_S_DEFECTIVE_TOKEN;
 385         goto cleanup;
 386     } else if (GSS_ERROR(major))
 387         goto cleanup;
 388
 389     if (frresp->code == PW_ACCESS_CHALLENGE) {
 390         major = gssEapRadiusGetAvp(minor, frresp->vps, PW_STATE, 0,
 391                                    &ctx->acceptorCtx.state, TRUE);
 392         if (major != GSS_S_UNAVAILABLE && GSS_ERROR(major))
 393             goto cleanup;
 394     } else {
 395         ctx->acceptorCtx.vps = frresp->vps;
 396         frresp->vps = NULL;
 397
 398         rs_conn_destroy(ctx->acceptorCtx.radConn);
 399         ctx->acceptorCtx.radConn = NULL;
 400
 401         major = acceptReadyEap(minor, ctx, cred);
 402         if (GSS_ERROR(major))
 403             goto cleanup;
 404
 405         ctx->state = EAP_STATE_EXTENSIONS_REQ;
 406     }
 407
 408     major = GSS_S_CONTINUE_NEEDED;
 409
 410 cleanup:
 411     rs_request_destroy(request);
 412
 413     return major;
 414 }
 415
 416 static OM_uint32
 417 eapGssSmAcceptExtensionsReq(OM_uint32 *minor,
 418                             gss_ctx_id_t ctx,
 419                             gss_cred_id_t cred,
 420                             gss_buffer_t inputToken,
 421                             gss_channel_bindings_t chanBindings,
 422                             gss_buffer_t outputToken)
 423 {
 424     OM_uint32 major;
 425
 426     major = gssEapVerifyExtensions(minor, cred, ctx, chanBindings, inputToken);
 427     if (GSS_ERROR(major))
 428         return major;
 429
 430     outputToken->length = 0;
 431     outputToken->value = NULL;
 432
 433     ctx->state = EAP_STATE_EXTENSIONS_RESP;
 434
 435     return GSS_S_CONTINUE_NEEDED;
 436 }
 437
 438 static OM_uint32
 439 eapGssSmAcceptExtensionsResp(OM_uint32 *minor,
 440                              gss_ctx_id_t ctx,
 441                              gss_cred_id_t cred,
 442                              gss_buffer_t inputToken,
 443                              gss_channel_bindings_t chanBindings,
 444                              gss_buffer_t outputToken)
 445 {
 446     OM_uint32 major;
 447
 448     major = gssEapMakeExtensions(minor, cred, ctx, chanBindings, outputToken);
 449     if (GSS_ERROR(major))
 450         return major;
 451
 452     ctx->state = EAP_STATE_ESTABLISHED;
 453
 454     return GSS_S_COMPLETE;
 455 }
 456
 457 static OM_uint32
 458 eapGssSmAcceptEstablished(OM_uint32 *minor,
 459                           gss_ctx_id_t ctx,
 460                           gss_cred_id_t cred,
 461                           gss_buffer_t inputToken,
 462                           gss_channel_bindings_t chanBindings,
 463                           gss_buffer_t outputToken)
 464 {
 465     /* Called with already established context */
 466     *minor = GSSEAP_CONTEXT_ESTABLISHED;
 467     return GSS_S_BAD_STATUS;
 468 }
 469
 470 static OM_uint32
 471 makeErrorToken(OM_uint32 *minor,
 472                OM_uint32 majorStatus,
 473                OM_uint32 minorStatus,
 474                gss_buffer_t outputToken)
 475 {
 476     unsigned char errorData[8];
 477     gss_buffer_desc errorBuffer;
 478
 479     assert(GSS_ERROR(majorStatus));
 480
 481     /*
 482      * Only return error codes that the initiator could have caused,
 483      * to avoid information leakage.
 484      */
 485     switch (minorStatus) {
 486     case GSSEAP_WRONG_SIZE:
 487     case GSSEAP_WRONG_MECH:
 488     case GSSEAP_BAD_TOK_HEADER:
 489     case GSSEAP_BAD_DIRECTION:
 490     case GSSEAP_WRONG_TOK_ID:
 491     case GSSEAP_CRIT_EXT_UNAVAILABLE:
 492     case GSSEAP_MISSING_REQUIRED_EXT:
 493     case GSSEAP_KEY_UNAVAILABLE:
 494     case GSSEAP_KEY_TOO_SHORT:
 495     case GSSEAP_RADIUS_AUTH_FAILURE:
 496     case GSSEAP_UNKNOWN_RADIUS_CODE:
 497     case GSSEAP_MISSING_EAP_REQUEST:
 498         break;
 499     default:
 500         /* Don't return system error codes */
 501         if (IS_RADIUS_ERROR(minorStatus))
 502             minorStatus = GSSEAP_GENERIC_RADIUS_ERROR;
 503         else
 504             return GSS_S_COMPLETE;
 505     }
 506
 507     minorStatus -= ERROR_TABLE_BASE_eapg;
 508
 509     store_uint32_be(majorStatus, &errorData[0]);
 510     store_uint32_be(minorStatus, &errorData[4]);
 511
 512     errorBuffer.length = sizeof(errorData);
 513     errorBuffer.value = errorData;
 514
 515     return duplicateBuffer(minor, &errorBuffer, outputToken);
 516 }
 517
 518 static struct gss_eap_acceptor_sm {
 519     enum gss_eap_token_type inputTokenType;
 520     enum gss_eap_token_type outputTokenType;
 521     OM_uint32 (*processToken)(OM_uint32 *,
 522                               gss_ctx_id_t,
 523                               gss_cred_id_t,
 524                               gss_buffer_t,
 525                               gss_channel_bindings_t,
 526                               gss_buffer_t);
 527 } eapGssAcceptorSm[] = {
 528     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,       eapGssSmAcceptIdentity           },
 529     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,       eapGssSmAcceptAuthenticate       },
 530     { TOK_TYPE_EXT_REQ,     TOK_TYPE_NONE,          eapGssSmAcceptExtensionsReq      },
 531     { TOK_TYPE_NONE,        TOK_TYPE_EXT_RESP,      eapGssSmAcceptExtensionsResp     },
 532     { TOK_TYPE_NONE,        TOK_TYPE_NONE,          eapGssSmAcceptEstablished        },
 533     { TOK_TYPE_NONE,        TOK_TYPE_CONTEXT_ERR,   NULL                             },
 534 #ifdef GSSEAP_ENABLE_REAUTH
 535     { TOK_TYPE_GSS_REAUTH,  TOK_TYPE_GSS_REAUTH,    eapGssSmAcceptGssReauth          },
 536 #endif
 537 };
 538
 539 OM_uint32
 540 gss_accept_sec_context(OM_uint32 *minor,
 541                        gss_ctx_id_t *context_handle,
 542                        gss_cred_id_t cred,
 543                        gss_buffer_t input_token,
 544                        gss_channel_bindings_t input_chan_bindings,
 545                        gss_name_t *src_name,
 546                        gss_OID *mech_type,
 547                        gss_buffer_t output_token,
 548                        OM_uint32 *ret_flags,
 549                        OM_uint32 *time_rec,
 550                        gss_cred_id_t *delegated_cred_handle)
 551 {
 552     OM_uint32 major;
 553     OM_uint32 tmpMajor, tmpMinor;
 554     gss_ctx_id_t ctx = *context_handle;
 555     struct gss_eap_acceptor_sm *sm = NULL;
 556     gss_buffer_desc innerInputToken = GSS_C_EMPTY_BUFFER;
 557     gss_buffer_desc innerOutputToken = GSS_C_EMPTY_BUFFER;
 558     enum gss_eap_token_type tokType;
 559     int initialContextToken = 0;
 560
 561     *minor = 0;
 562
 563     output_token->length = 0;
 564     output_token->value = NULL;
 565
 566     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 567         return GSS_S_DEFECTIVE_TOKEN;
 568     }
 569
 570     if (ctx == GSS_C_NO_CONTEXT) {
 571         major = gssEapAllocContext(minor, &ctx);
 572         if (GSS_ERROR(major))
 573             return major;
 574
 575         initialContextToken = 1;
 576         *context_handle = ctx;
 577     }
 578
 579     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 580
 581     /* Validate and lock credentials */
 582     if (cred != GSS_C_NO_CREDENTIAL) {
 583         GSSEAP_MUTEX_LOCK(&cred->mutex);
 584
 585         if ((cred->flags & CRED_FLAG_ACCEPT) == 0) {
 586             *minor = GSSEAP_CRED_USAGE_MISMATCH;
 587             major = GSS_S_NO_CRED;
 588             goto cleanup;
 589         }
 590     }
 591
 592     sm = &eapGssAcceptorSm[ctx->state];
 593
 594     major = gssEapVerifyToken(minor, ctx, input_token,
 595                               &tokType, &innerInputToken);
 596     if (GSS_ERROR(major))
 597         goto cleanup;
 598
 599     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 600         *minor = GSSEAP_WRONG_MECH;
 601         major = GSS_S_BAD_MECH;
 602         goto cleanup;
 603     }
 604
 605 #ifdef GSSEAP_ENABLE_REAUTH
 606     /*
 607      * If we're built with fast reauthentication support, it's valid
 608      * for an initiator to send a GSS reauthentication token as its
 609      * initial context token, causing us to short-circuit the state
 610      * machine and process Kerberos GSS messages instead.
 611      */
 612     if (tokType == TOK_TYPE_GSS_REAUTH && initialContextToken) {
 613         ctx->state = EAP_STATE_KRB_REAUTH_GSS;
 614     } else
 615 #endif
 616     if (tokType != sm->inputTokenType) {
 617         *minor = GSSEAP_WRONG_TOK_ID;
 618         major = GSS_S_DEFECTIVE_TOKEN;
 619         goto cleanup;
 620     }
 621
 622     do {
 623         sm = &eapGssAcceptorSm[ctx->state];
 624
 625         major = (sm->processToken)(minor,
 626                                    ctx,
 627                                    cred,
 628                                    &innerInputToken,
 629                                    input_chan_bindings,
 630                                    &innerOutputToken);
 631         if (GSS_ERROR(major)) {
 632             /* Generate an error token */
 633             tmpMajor = makeErrorToken(&tmpMinor, major, *minor, &innerOutputToken);
 634             if (GSS_ERROR(tmpMajor)) {
 635                 major = tmpMajor;
 636                 goto cleanup;
 637             }
 638
 639             sm = &eapGssAcceptorSm[EAP_STATE_ERROR];
 640             goto send_token;
 641         }
 642     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.length == 0);
 643
 644     if (mech_type != NULL) {
 645         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 646             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 647     }
 648     if (ret_flags != NULL)
 649         *ret_flags = ctx->gssFlags;
 650     if (delegated_cred_handle != NULL)
 651         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 652
 653     if (major == GSS_S_COMPLETE) {
 654         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 655             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
 656             if (GSS_ERROR(major))
 657                 goto cleanup;
 658         }
 659         if (time_rec != NULL)
 660             gssEapContextTime(&tmpMinor, ctx, time_rec);
 661     }
 662
 663     assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 664
 665 send_token:
 666     if (innerOutputToken.value != NULL) {
 667         tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
 668                                    sm->outputTokenType, output_token);
 669         if (GSS_ERROR(tmpMajor)) {
 670             major = tmpMajor;
 671             *minor = tmpMinor;
 672             goto cleanup;
 673         }
 674     }
 675
 676 cleanup:
 677     if (cred != GSS_C_NO_CREDENTIAL)
 678         GSSEAP_MUTEX_UNLOCK(&cred->mutex);
 679     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 680
 681     if (GSS_ERROR(major))
 682         gssEapReleaseContext(&tmpMinor, context_handle);
 683
 684     gss_release_buffer(&tmpMinor, &innerOutputToken);
 685
 686     return major;
 687 }
 688
 689 #ifdef GSSEAP_ENABLE_REAUTH
 690 static OM_uint32
 691 acceptReadyKrb(OM_uint32 *minor,
 692                gss_ctx_id_t ctx,
 693                gss_cred_id_t cred,
 694                const gss_name_t initiator,
 695                const gss_OID mech,
 696                OM_uint32 timeRec)
 697 {
 698     OM_uint32 major;
 699
 700     major = gssEapGlueToMechName(minor, initiator, &ctx->initiatorName);
 701     if (GSS_ERROR(major))
 702         return major;
 703
 704     if (cred != GSS_C_NO_CREDENTIAL && cred->name != GSS_C_NO_NAME) {
 705         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 706         if (GSS_ERROR(major))
 707             return major;
 708     }
 709
 710     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
 711     if (GSS_ERROR(major))
 712         return major;
 713
 714     ctx->state = EAP_STATE_ESTABLISHED;
 715
 716     return GSS_S_COMPLETE;
 717 }
 718
 719 static OM_uint32
 720 eapGssSmAcceptGssReauth(OM_uint32 *minor,
 721                         gss_ctx_id_t ctx,
 722                         gss_cred_id_t cred,
 723                         gss_buffer_t inputToken,
 724                         gss_channel_bindings_t chanBindings,
 725                         gss_buffer_t outputToken)
 726 {
 727     OM_uint32 major, tmpMinor;
 728     gss_cred_id_t krbCred = GSS_C_NO_CREDENTIAL;
 729     gss_name_t krbInitiator = GSS_C_NO_NAME;
 730     gss_OID mech = GSS_C_NO_OID;
 731     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
 732
 733     ctx->flags |= CTX_FLAG_KRB_REAUTH_GSS;
 734
 735     if (cred != GSS_C_NO_CREDENTIAL)
 736         krbCred = cred->krbCred;
 737
 738     major = gssAcceptSecContext(minor,
 739                                 &ctx->kerberosCtx,
 740                                 krbCred,
 741                                 inputToken,
 742                                 chanBindings,
 743                                 &krbInitiator,
 744                                 &mech,
 745                                 outputToken,
 746                                 &gssFlags,
 747                                 &timeRec,
 748                                 NULL);
 749     if (major == GSS_S_COMPLETE) {
 750         major = acceptReadyKrb(minor, ctx, cred,
 751                                krbInitiator, mech, timeRec);
 752     }
 753
 754     ctx->gssFlags = gssFlags;
 755
 756     gssReleaseName(&tmpMinor, &krbInitiator);
 757
 758     return major;
 759 }
 760 #endif /* GSSEAP_ENABLE_REAUTH */