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