mech_eap/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 gssEapSupportedInitiatorExts[] = {
 129 };
 130
 131 static struct gss_eap_itok_map
 132 gssEapAcceptorExtsFlagMap[] = {
 133     { ITOK_TYPE_REAUTH_CREDS, CTX_FLAG_KRB_REAUTH_SUPPORTED },
 134 };
 135
 136 static OM_uint32
 137 eapGssSmAcceptExts(OM_uint32 *minor,
 138                    gss_cred_id_t cred,
 139                    gss_ctx_id_t ctx,
 140                    gss_name_t target,
 141                    gss_OID mech,
 142                    OM_uint32 reqFlags,
 143                    OM_uint32 timeReq,
 144                    gss_channel_bindings_t chanBindings,
 145                    gss_buffer_t inputToken,
 146                    gss_buffer_t outputToken,
 147                    OM_uint32 *smFlags)
 148 {
 149     OM_uint32 major;
 150
 151     major = gssEapProcessSupportedExts(minor, inputToken,
 152                                        gssEapAcceptorExtsFlagMap,
 153                                         sizeof(gssEapAcceptorExtsFlagMap) /
 154                                        sizeof(gssEapAcceptorExtsFlagMap[0]),
 155                                        &ctx->flags);
 156     if (GSS_ERROR(major))
 157         return major;
 158
 159     major = gssEapEncodeSupportedExts(minor,
 160                                       gssEapSupportedInitiatorExts,
 161                                       sizeof(gssEapSupportedInitiatorExts) /
 162                                         sizeof(gssEapSupportedInitiatorExts[0]),
 163                                       outputToken);
 164     if (GSS_ERROR(major))
 165         return major;
 166
 167     return GSS_S_CONTINUE_NEEDED;
 168 }
 169
 170 static OM_uint32
 171 eapGssSmAcceptAcceptorName(OM_uint32 *minor,
 172                            gss_cred_id_t cred,
 173                            gss_ctx_id_t ctx,
 174                            gss_name_t target,
 175                            gss_OID mech,
 176                            OM_uint32 reqFlags,
 177                            OM_uint32 timeReq,
 178                            gss_channel_bindings_t chanBindings,
 179                            gss_buffer_t inputToken,
 180                            gss_buffer_t outputToken,
 181                            OM_uint32 *smFlags)
 182 {
 183     OM_uint32 major;
 184
 185     /* XXX TODO import and validate name from inputToken */
 186
 187     if (ctx->acceptorName != GSS_C_NO_NAME) {
 188         /* Send desired target name to acceptor */
 189         major = gssEapDisplayName(minor, ctx->acceptorName,
 190                                   outputToken, NULL);
 191         if (GSS_ERROR(major))
 192             return major;
 193     }
 194
 195     return GSS_S_CONTINUE_NEEDED;
 196 }
 197
 198 #ifdef GSSEAP_DEBUG
 199 static OM_uint32
 200 eapGssSmAcceptVendorInfo(OM_uint32 *minor,
 201                          gss_cred_id_t cred,
 202                          gss_ctx_id_t ctx,
 203                          gss_name_t target,
 204                          gss_OID mech,
 205                          OM_uint32 reqFlags,
 206                          OM_uint32 timeReq,
 207                          gss_channel_bindings_t chanBindings,
 208                          gss_buffer_t inputToken,
 209                          gss_buffer_t outputToken,
 210                          OM_uint32 *smFlags)
 211 {
 212     fprintf(stderr, "GSS-EAP: vendor: %.*s\n",
 213             (int)inputToken->length, (char *)inputToken->value);
 214
 215     return GSS_S_CONTINUE_NEEDED;
 216 }
 217 #endif
 218
 219
 220 /*
 221  * Emit a identity EAP request to force the initiator (peer) to identify
 222  * itself.
 223  */
 224 static OM_uint32
 225 eapGssSmAcceptIdentity(OM_uint32 *minor,
 226                        gss_cred_id_t cred,
 227                        gss_ctx_id_t ctx,
 228                        gss_name_t target,
 229                        gss_OID mech,
 230                        OM_uint32 reqFlags,
 231                        OM_uint32 timeReq,
 232                        gss_channel_bindings_t chanBindings,
 233                        gss_buffer_t inputToken,
 234                        gss_buffer_t outputToken,
 235                        OM_uint32 *smFlags)
 236 {
 237     OM_uint32 major;
 238     struct wpabuf *reqData;
 239     gss_buffer_desc pktBuffer;
 240
 241     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 242         *minor = GSSEAP_CRED_MECH_MISMATCH;
 243         return GSS_S_BAD_MECH;
 244     }
 245
 246     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
 247         *minor = GSSEAP_WRONG_SIZE;
 248         return GSS_S_DEFECTIVE_TOKEN;
 249     }
 250
 251     reqData = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY, 0,
 252                             EAP_CODE_REQUEST, 0);
 253     if (reqData == NULL) {
 254         *minor = ENOMEM;
 255         return GSS_S_FAILURE;
 256     }
 257
 258     pktBuffer.length = wpabuf_len(reqData);
 259     pktBuffer.value = (void *)wpabuf_head(reqData);
 260
 261     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 262     if (GSS_ERROR(major))
 263         return major;
 264
 265     wpabuf_free(reqData);
 266
 267     GSSEAP_SM_TRANSITION_NEXT(ctx);
 268
 269     *minor = 0;
 270     *smFlags |= SM_FLAG_SEND_TOKEN | SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 271
 272     return GSS_S_CONTINUE_NEEDED;
 273 }
 274
 275 /*
 276  * Returns TRUE if the input token contains an EAP identity response.
 277  */
 278 static int
 279 isIdentityResponseP(gss_buffer_t inputToken)
 280 {
 281     struct wpabuf respData;
 282
 283     wpabuf_set(&respData, inputToken->value, inputToken->length);
 284
 285     return (eap_get_type(&respData) == EAP_TYPE_IDENTITY);
 286 }
 287
 288 /*
 289  * Save the asserted initiator identity from the EAP identity response.
 290  */
 291 static OM_uint32
 292 importInitiatorIdentity(OM_uint32 *minor,
 293                         gss_ctx_id_t ctx,
 294                         gss_buffer_t inputToken)
 295 {
 296     OM_uint32 tmpMinor;
 297     struct wpabuf respData;
 298     const unsigned char *pos;
 299     size_t len;
 300     gss_buffer_desc nameBuf;
 301
 302     wpabuf_set(&respData, inputToken->value, inputToken->length);
 303
 304     pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY,
 305                            &respData, &len);
 306     if (pos == NULL) {
 307         *minor = GSSEAP_PEER_BAD_MESSAGE;
 308         return GSS_S_DEFECTIVE_TOKEN;
 309     }
 310
 311     nameBuf.value = (void *)pos;
 312     nameBuf.length = len;
 313
 314     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
 315
 316     return gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
 317                             &ctx->initiatorName);
 318 }
 319
 320 /*
 321  * Pass the asserted initiator identity to the authentication server.
 322  */
 323 static OM_uint32
 324 setInitiatorIdentity(OM_uint32 *minor,
 325                      gss_ctx_id_t ctx,
 326                      VALUE_PAIR **vps)
 327 {
 328     OM_uint32 major, tmpMinor;
 329     gss_buffer_desc nameBuf;
 330
 331     /*
 332      * We should have got an EAP identity response, but if we didn't, then
 333      * we will just avoid sending User-Name. Note that radsecproxy requires
 334      * User-Name to be sent on every request (presumably so it can remain
 335      * stateless).
 336      */
 337     if (ctx->initiatorName != GSS_C_NO_NAME) {
 338         major = gssEapDisplayName(minor, ctx->initiatorName, &nameBuf, NULL);
 339         if (GSS_ERROR(major))
 340             return major;
 341
 342         major = gssEapRadiusAddAvp(minor, vps, PW_USER_NAME, 0, &nameBuf);
 343         if (GSS_ERROR(major))
 344             return major;
 345
 346         gss_release_buffer(&tmpMinor, &nameBuf);
 347     }
 348
 349     *minor = 0;
 350     return GSS_S_COMPLETE;
 351 }
 352
 353 /*
 354  * Pass the asserted acceptor identity to the authentication server.
 355  */
 356 static OM_uint32
 357 setAcceptorIdentity(OM_uint32 *minor,
 358                     gss_ctx_id_t ctx,
 359                     VALUE_PAIR **vps)
 360 {
 361     OM_uint32 major;
 362     gss_buffer_desc nameBuf;
 363     krb5_context krbContext = NULL;
 364     krb5_principal krbPrinc;
 365     struct rs_context *rc = ctx->acceptorCtx.radContext;
 366
 367     assert(rc != NULL);
 368
 369     if (ctx->acceptorName == GSS_C_NO_NAME) {
 370         *minor = 0;
 371         return GSS_S_COMPLETE;
 372     }
 373
 374     if ((ctx->acceptorName->flags & NAME_FLAG_SERVICE) == 0) {
 375         *minor = GSSEAP_BAD_SERVICE_NAME;
 376         return GSS_S_BAD_NAME;
 377     }
 378
 379     GSSEAP_KRB_INIT(&krbContext);
 380
 381     krbPrinc = ctx->acceptorName->krbPrincipal;
 382     assert(krbPrinc != NULL);
 383     assert(KRB_PRINC_LENGTH(krbPrinc) >= 2);
 384
 385     /* Acceptor-Service-Name */
 386     krbPrincComponentToGssBuffer(krbPrinc, 0, &nameBuf);
 387
 388     major = gssEapRadiusAddAvp(minor, vps,
 389                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 390                                VENDORPEC_UKERNA,
 391                                &nameBuf);
 392     if (GSS_ERROR(major))
 393         return major;
 394
 395     /* Acceptor-Host-Name */
 396     krbPrincComponentToGssBuffer(krbPrinc, 1, &nameBuf);
 397
 398     major = gssEapRadiusAddAvp(minor, vps,
 399                                PW_GSS_ACCEPTOR_HOST_NAME,
 400                                VENDORPEC_UKERNA,
 401                                &nameBuf);
 402     if (GSS_ERROR(major))
 403         return major;
 404
 405     if (KRB_PRINC_LENGTH(krbPrinc) > 2) {
 406         /* Acceptor-Service-Specific */
 407         krb5_principal_data ssiPrinc = *krbPrinc;
 408         char *ssi;
 409
 410         KRB_PRINC_LENGTH(&ssiPrinc) -= 2;
 411         KRB_PRINC_NAME(&ssiPrinc) += 2;
 412
 413         *minor = krb5_unparse_name_flags(krbContext, &ssiPrinc,
 414                                          KRB5_PRINCIPAL_UNPARSE_NO_REALM, &ssi);
 415         if (*minor != 0)
 416             return GSS_S_FAILURE;
 417
 418         nameBuf.value = ssi;
 419         nameBuf.length = strlen(ssi);
 420
 421         major = gssEapRadiusAddAvp(minor, vps,
 422                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFIC,
 423                                    VENDORPEC_UKERNA,
 424                                    &nameBuf);
 425
 426         if (GSS_ERROR(major)) {
 427             krb5_free_unparsed_name(krbContext, ssi);
 428             return major;
 429         }
 430         krb5_free_unparsed_name(krbContext, ssi);
 431     }
 432
 433     krbPrincRealmToGssBuffer(krbPrinc, &nameBuf);
 434     if (nameBuf.length != 0) {
 435         /* Acceptor-Realm-Name */
 436         major = gssEapRadiusAddAvp(minor, vps,
 437                                    PW_GSS_ACCEPTOR_REALM_NAME,
 438                                    VENDORPEC_UKERNA,
 439                                    &nameBuf);
 440         if (GSS_ERROR(major))
 441             return major;
 442     }
 443
 444     *minor = 0;
 445     return GSS_S_COMPLETE;
 446 }
 447
 448 /*
 449  * Allocate a RadSec handle
 450  */
 451 static OM_uint32
 452 createRadiusHandle(OM_uint32 *minor,
 453                    gss_cred_id_t cred,
 454                    gss_ctx_id_t ctx)
 455 {
 456     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 457     const char *configFile = RS_CONFIG_FILE;
 458     const char *configStanza = "gss-eap";
 459     struct rs_alloc_scheme ralloc;
 460     struct rs_error *err;
 461
 462     assert(actx->radContext == NULL);
 463     assert(actx->radConn == NULL);
 464
 465     if (rs_context_create(&actx->radContext, RS_DICT_FILE) != 0) {
 466         *minor = GSSEAP_RADSEC_CONTEXT_FAILURE;
 467         return GSS_S_FAILURE;
 468     }
 469
 470     if (cred->radiusConfigFile != NULL)
 471         configFile = cred->radiusConfigFile;
 472     if (cred->radiusConfigStanza != NULL)
 473         configStanza = cred->radiusConfigStanza;
 474
 475     ralloc.calloc  = GSSEAP_CALLOC;
 476     ralloc.malloc  = GSSEAP_MALLOC;
 477     ralloc.free    = GSSEAP_FREE;
 478     ralloc.realloc = GSSEAP_REALLOC;
 479
 480     rs_context_set_alloc_scheme(actx->radContext, &ralloc);
 481
 482     if (rs_context_read_config(actx->radContext, configFile) != 0) {
 483         err = rs_err_ctx_pop(actx->radContext);
 484         goto fail;
 485     }
 486
 487     if (rs_conn_create(actx->radContext, &actx->radConn, configStanza) != 0) {
 488         err = rs_err_conn_pop(actx->radConn);
 489         goto fail;
 490     }
 491
 492     if (actx->radServer != NULL) {
 493         if (rs_conn_select_peer(actx->radConn, actx->radServer) != 0) {
 494             err = rs_err_conn_pop(actx->radConn);
 495             goto fail;
 496         }
 497     }
 498
 499     *minor = 0;
 500     return GSS_S_COMPLETE;
 501
 502 fail:
 503     return gssEapRadiusMapError(minor, err);
 504 }
 505
 506 /*
 507  * Process a EAP response from the initiator.
 508  */
 509 static OM_uint32
 510 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 511                            gss_cred_id_t cred,
 512                            gss_ctx_id_t ctx,
 513                            gss_name_t target,
 514                            gss_OID mech,
 515                            OM_uint32 reqFlags,
 516                            OM_uint32 timeReq,
 517                            gss_channel_bindings_t chanBindings,
 518                            gss_buffer_t inputToken,
 519                            gss_buffer_t outputToken,
 520                            OM_uint32 *smFlags)
 521 {
 522     OM_uint32 major, tmpMinor;
 523     struct rs_connection *rconn;
 524     struct rs_request *request = NULL;
 525     struct rs_packet *req = NULL, *resp = NULL;
 526     struct radius_packet *frreq, *frresp;
 527
 528     if (ctx->acceptorCtx.radContext == NULL) {
 529         /* May be NULL from an imported partial context */
 530         major = createRadiusHandle(minor, cred, ctx);
 531         if (GSS_ERROR(major))
 532             goto cleanup;
 533     }
 534
 535     if (isIdentityResponseP(inputToken)) {
 536         major = importInitiatorIdentity(minor, ctx, inputToken);
 537         if (GSS_ERROR(major))
 538             return major;
 539     }
 540
 541     rconn = ctx->acceptorCtx.radConn;
 542
 543     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 544         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 545         goto cleanup;
 546     }
 547     frreq = rs_packet_frpkt(req);
 548
 549     major = setInitiatorIdentity(minor, ctx, &frreq->vps);
 550     if (GSS_ERROR(major))
 551         goto cleanup;
 552
 553     major = setAcceptorIdentity(minor, ctx, &frreq->vps);
 554     if (GSS_ERROR(major))
 555         goto cleanup;
 556
 557     major = gssEapRadiusAddAvp(minor, &frreq->vps,
 558                                PW_EAP_MESSAGE, 0, inputToken);
 559     if (GSS_ERROR(major))
 560         goto cleanup;
 561
 562     if (ctx->acceptorCtx.state.length != 0) {
 563         major = gssEapRadiusAddAvp(minor, &frreq->vps, PW_STATE, 0,
 564                                    &ctx->acceptorCtx.state);
 565         if (GSS_ERROR(major))
 566             goto cleanup;
 567
 568         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 569     }
 570
 571     if (rs_request_create(rconn, &request) != 0) {
 572         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 573         goto cleanup;
 574     }
 575
 576     rs_request_add_reqpkt(request, req);
 577     req = NULL;
 578
 579     if (rs_request_send(request, &resp) != 0) {
 580         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 581         goto cleanup;
 582     }
 583
 584     assert(resp != NULL);
 585
 586     frresp = rs_packet_frpkt(resp);
 587     switch (frresp->code) {
 588     case PW_ACCESS_CHALLENGE:
 589     case PW_AUTHENTICATION_ACK:
 590         break;
 591     case PW_AUTHENTICATION_REJECT:
 592         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 593         major = GSS_S_DEFECTIVE_CREDENTIAL;
 594         goto cleanup;
 595         break;
 596     default:
 597         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 598         major = GSS_S_FAILURE;
 599         goto cleanup;
 600         break;
 601     }
 602
 603     major = gssEapRadiusGetAvp(minor, frresp->vps, PW_EAP_MESSAGE, 0,
 604                                outputToken, TRUE);
 605     if (major == GSS_S_UNAVAILABLE && frresp->code == PW_ACCESS_CHALLENGE) {
 606         *minor = GSSEAP_MISSING_EAP_REQUEST;
 607         major = GSS_S_DEFECTIVE_TOKEN;
 608         goto cleanup;
 609     } else if (GSS_ERROR(major))
 610         goto cleanup;
 611
 612     if (frresp->code == PW_ACCESS_CHALLENGE) {
 613         major = gssEapRadiusGetAvp(minor, frresp->vps, PW_STATE, 0,
 614                                    &ctx->acceptorCtx.state, TRUE);
 615         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 616             goto cleanup;
 617     } else {
 618         ctx->acceptorCtx.vps = frresp->vps;
 619         frresp->vps = NULL;
 620
 621         major = acceptReadyEap(minor, ctx, cred);
 622         if (GSS_ERROR(major))
 623             goto cleanup;
 624
 625         GSSEAP_SM_TRANSITION_NEXT(ctx);
 626     }
 627
 628     major = GSS_S_CONTINUE_NEEDED;
 629     *minor = 0;
 630     *smFlags |= SM_FLAG_SEND_TOKEN | SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 631
 632 cleanup:
 633     if (request != NULL)
 634         rs_request_destroy(request);
 635     if (req != NULL)
 636         rs_packet_destroy(req);
 637     if (resp != NULL)
 638         rs_packet_destroy(resp);
 639     if (GSSEAP_SM_STATE(ctx) == GSSEAP_STATE_INITIATOR_EXTS) {
 640         assert(major == GSS_S_CONTINUE_NEEDED);
 641
 642         rs_conn_destroy(ctx->acceptorCtx.radConn);
 643         ctx->acceptorCtx.radConn = NULL;
 644     }
 645
 646     return major;
 647 }
 648
 649 static OM_uint32
 650 eapGssSmAcceptGssChannelBindings(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, tmpMinor;
 663     gss_iov_buffer_desc iov[2];
 664
 665     if (ctx->flags & CTX_FLAG_KRB_REAUTH)
 666         return GSS_S_CONTINUE_NEEDED;
 667
 668     iov[0].type = GSS_IOV_BUFFER_TYPE_DATA | GSS_IOV_BUFFER_FLAG_ALLOCATE;
 669     iov[0].buffer.length = 0;
 670     iov[0].buffer.value = NULL;
 671
 672     iov[1].type = GSS_IOV_BUFFER_TYPE_STREAM;
 673     iov[1].buffer = *inputToken;
 674
 675     major = gssEapUnwrapOrVerifyMIC(minor, ctx, NULL, NULL,
 676                                     iov, 2, TOK_TYPE_WRAP);
 677     if (GSS_ERROR(major))
 678         return major;
 679
 680     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS &&
 681         !bufferEqual(&iov[0].buffer, &chanBindings->application_data)) {
 682         major = GSS_S_BAD_BINDINGS;
 683         *minor = GSSEAP_BINDINGS_MISMATCH;
 684     } else {
 685         major = GSS_S_CONTINUE_NEEDED;
 686         *minor = 0;
 687     }
 688
 689     gss_release_buffer(&tmpMinor, &iov[0].buffer);
 690
 691     return major;
 692 }
 693
 694 #ifdef GSSEAP_ENABLE_REAUTH
 695 static OM_uint32
 696 eapGssSmAcceptReauthCreds(OM_uint32 *minor,
 697                           gss_cred_id_t cred,
 698                           gss_ctx_id_t ctx,
 699                           gss_name_t target,
 700                           gss_OID mech,
 701                           OM_uint32 reqFlags,
 702                           OM_uint32 timeReq,
 703                           gss_channel_bindings_t chanBindings,
 704                           gss_buffer_t inputToken,
 705                           gss_buffer_t outputToken,
 706                           OM_uint32 *smFlags)
 707 {
 708     OM_uint32 major;
 709
 710     /*
 711      * If we're built with fast reauthentication enabled, then
 712      * fabricate a ticket from the initiator to ourselves.
 713      */
 714     if (ctx->flags & CTX_FLAG_KRB_REAUTH_SUPPORTED)
 715         major = gssEapMakeReauthCreds(minor, ctx, cred, outputToken);
 716     else
 717         major = GSS_S_UNAVAILABLE;
 718
 719     if (major == GSS_S_UNAVAILABLE)
 720         major = GSS_S_COMPLETE;
 721
 722     return GSS_ERROR(major) ? major : GSS_S_CONTINUE_NEEDED;
 723 }
 724 #endif
 725
 726 static OM_uint32
 727 eapGssSmAcceptInitiatorMIC(OM_uint32 *minor,
 728                            gss_cred_id_t cred,
 729                            gss_ctx_id_t ctx,
 730                            gss_name_t target,
 731                            gss_OID mech,
 732                            OM_uint32 reqFlags,
 733                            OM_uint32 timeReq,
 734                            gss_channel_bindings_t chanBindings,
 735                            gss_buffer_t inputToken,
 736                            gss_buffer_t outputToken,
 737                            OM_uint32 *smFlags)
 738 {
 739     OM_uint32 major;
 740
 741     major = gssEapVerifyConversationMIC(minor, ctx, inputToken);
 742     if (GSS_ERROR(major))
 743         return major;
 744
 745     GSSEAP_SM_TRANSITION_NEXT(ctx);
 746
 747     *minor = 0;
 748
 749     return GSS_S_CONTINUE_NEEDED;
 750 }
 751
 752 static OM_uint32
 753 eapGssSmAcceptAcceptorMIC(OM_uint32 *minor,
 754                           gss_cred_id_t cred,
 755                           gss_ctx_id_t ctx,
 756                           gss_name_t target,
 757                           gss_OID mech,
 758                           OM_uint32 reqFlags,
 759                           OM_uint32 timeReq,
 760                           gss_channel_bindings_t chanBindings,
 761                           gss_buffer_t inputToken,
 762                           gss_buffer_t outputToken,
 763                           OM_uint32 *smFlags)
 764 {
 765     OM_uint32 major;
 766
 767     major = gssEapGetConversationMIC(minor, ctx, outputToken);
 768     if (GSS_ERROR(major))
 769         return major;
 770
 771     GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 772
 773     *minor = 0;
 774     *smFlags |= SM_FLAG_SEND_TOKEN | SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 775
 776     return GSS_S_COMPLETE;
 777 }
 778
 779 /*
 780  * Acceptor state machine.
 781  */
 782 static struct gss_eap_sm eapGssAcceptorSm[] = {
 783 #ifdef GSSEAP_ENABLE_REAUTH
 784     {
 785         ITOK_TYPE_REAUTH_REQ,
 786         ITOK_TYPE_REAUTH_RESP,
 787         GSSEAP_STATE_INITIAL | GSSEAP_STATE_REAUTHENTICATE,
 788         0,
 789         eapGssSmAcceptGssReauth,
 790     },
 791 #endif
 792     {
 793         ITOK_TYPE_ACCEPTOR_NAME_REQ,
 794         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 795         GSSEAP_STATE_INITIAL,
 796         0,
 797         eapGssSmAcceptAcceptorName
 798     },
 799     {
 800         ITOK_TYPE_SUPPORTED_ACCEPTOR_EXTS,
 801         ITOK_TYPE_SUPPORTED_INITIATOR_EXTS,
 802         GSSEAP_STATE_INITIAL,
 803         0,
 804         eapGssSmAcceptExts,
 805     },
 806 #ifdef GSSEAP_DEBUG
 807     {
 808         ITOK_TYPE_VENDOR_INFO,
 809         ITOK_TYPE_NONE,
 810         GSSEAP_STATE_INITIAL,
 811         0,
 812         eapGssSmAcceptVendorInfo,
 813     },
 814 #endif
 815     {
 816         ITOK_TYPE_NONE,
 817         ITOK_TYPE_EAP_REQ,
 818         GSSEAP_STATE_INITIAL,
 819         SM_ITOK_FLAG_REQUIRED,
 820         eapGssSmAcceptIdentity,
 821     },
 822     {
 823         ITOK_TYPE_EAP_RESP,
 824         ITOK_TYPE_EAP_REQ,
 825         GSSEAP_STATE_AUTHENTICATE,
 826         SM_ITOK_FLAG_REQUIRED,
 827         eapGssSmAcceptAuthenticate
 828     },
 829     {
 830         ITOK_TYPE_GSS_CHANNEL_BINDINGS,
 831         ITOK_TYPE_NONE,
 832         GSSEAP_STATE_INITIATOR_EXTS,
 833         0,
 834         eapGssSmAcceptGssChannelBindings,
 835     },
 836     {
 837         ITOK_TYPE_INITIATOR_MIC,
 838         ITOK_TYPE_NONE,
 839         GSSEAP_STATE_INITIATOR_EXTS,
 840         SM_ITOK_FLAG_REQUIRED,
 841         eapGssSmAcceptInitiatorMIC,
 842     },
 843 #ifdef GSSEAP_ENABLE_REAUTH
 844     {
 845         ITOK_TYPE_NONE,
 846         ITOK_TYPE_REAUTH_CREDS,
 847         GSSEAP_STATE_ACCEPTOR_EXTS,
 848         0,
 849         eapGssSmAcceptReauthCreds,
 850     },
 851 #endif
 852     {
 853         ITOK_TYPE_NONE,
 854         ITOK_TYPE_ACCEPTOR_MIC,
 855         GSSEAP_STATE_ACCEPTOR_EXTS,
 856         0,
 857         eapGssSmAcceptAcceptorMIC
 858     },
 859 };
 860
 861 OM_uint32
 862 gss_accept_sec_context(OM_uint32 *minor,
 863                        gss_ctx_id_t *context_handle,
 864                        gss_cred_id_t cred,
 865                        gss_buffer_t input_token,
 866                        gss_channel_bindings_t input_chan_bindings,
 867                        gss_name_t *src_name,
 868                        gss_OID *mech_type,
 869                        gss_buffer_t output_token,
 870                        OM_uint32 *ret_flags,
 871                        OM_uint32 *time_rec,
 872                        gss_cred_id_t *delegated_cred_handle)
 873 {
 874     OM_uint32 major, tmpMinor;
 875     gss_ctx_id_t ctx = *context_handle;
 876
 877     *minor = 0;
 878
 879     output_token->length = 0;
 880     output_token->value = NULL;
 881
 882     if (src_name != NULL)
 883         *src_name = GSS_C_NO_NAME;
 884
 885     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 886         *minor = GSSEAP_TOK_TRUNC;
 887         return GSS_S_DEFECTIVE_TOKEN;
 888     }
 889
 890     if (ctx == GSS_C_NO_CONTEXT) {
 891         major = gssEapAllocContext(minor, &ctx);
 892         if (GSS_ERROR(major))
 893             return major;
 894
 895         *context_handle = ctx;
 896     }
 897
 898     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 899
 900     if (cred == GSS_C_NO_CREDENTIAL) {
 901         if (ctx->defaultCred == GSS_C_NO_CREDENTIAL) {
 902             major = gssEapAcquireCred(minor,
 903                                       GSS_C_NO_NAME,
 904                                       GSS_C_NO_BUFFER,
 905                                       GSS_C_INDEFINITE,
 906                                       GSS_C_NO_OID_SET,
 907                                       GSS_C_ACCEPT,
 908                                       &ctx->defaultCred,
 909                                       NULL,
 910                                       NULL);
 911             if (GSS_ERROR(major))
 912                 goto cleanup;
 913         }
 914
 915         cred = ctx->defaultCred;
 916     }
 917
 918     GSSEAP_MUTEX_LOCK(&cred->mutex);
 919
 920     if (cred->name != GSS_C_NO_NAME) {
 921         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 922         if (GSS_ERROR(major))
 923             goto cleanup;
 924     }
 925
 926     major = gssEapSmStep(minor,
 927                          cred,
 928                          ctx,
 929                          GSS_C_NO_NAME,
 930                          GSS_C_NO_OID,
 931                          0,
 932                          GSS_C_INDEFINITE,
 933                          input_chan_bindings,
 934                          input_token,
 935                          output_token,
 936                          eapGssAcceptorSm,
 937                          sizeof(eapGssAcceptorSm) / sizeof(eapGssAcceptorSm[0]));
 938     if (GSS_ERROR(major))
 939         goto cleanup;
 940
 941     if (mech_type != NULL) {
 942         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 943             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 944     }
 945     if (ret_flags != NULL)
 946         *ret_flags = ctx->gssFlags;
 947     if (delegated_cred_handle != NULL)
 948         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 949
 950     if (major == GSS_S_COMPLETE) {
 951         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 952             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
 953             if (GSS_ERROR(major))
 954                 goto cleanup;
 955         }
 956         if (time_rec != NULL) {
 957             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
 958             if (GSS_ERROR(major))
 959                 goto cleanup;
 960         }
 961     }
 962
 963     assert(CTX_IS_ESTABLISHED(ctx) || major == GSS_S_CONTINUE_NEEDED);
 964
 965 cleanup:
 966     if (cred != GSS_C_NO_CREDENTIAL)
 967         GSSEAP_MUTEX_UNLOCK(&cred->mutex);
 968     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 969
 970     if (GSS_ERROR(major))
 971         gssEapReleaseContext(&tmpMinor, context_handle);
 972
 973     return major;
 974 }
 975
 976 #ifdef GSSEAP_ENABLE_REAUTH
 977 static OM_uint32
 978 acceptReadyKrb(OM_uint32 *minor,
 979                gss_ctx_id_t ctx,
 980                gss_cred_id_t cred,
 981                const gss_name_t initiator,
 982                const gss_OID mech,
 983                OM_uint32 timeRec)
 984 {
 985     OM_uint32 major;
 986
 987     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
 988     if (GSS_ERROR(major))
 989         return major;
 990
 991     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
 992     if (GSS_ERROR(major))
 993         return major;
 994
 995     *minor = 0;
 996     return GSS_S_COMPLETE;
 997 }
 998
 999 static OM_uint32
1000 eapGssSmAcceptGssReauth(OM_uint32 *minor,
1001                         gss_cred_id_t cred,
1002                         gss_ctx_id_t ctx,
1003                         gss_name_t target,
1004                         gss_OID mech,
1005                         OM_uint32 reqFlags,
1006                         OM_uint32 timeReq,
1007                         gss_channel_bindings_t userChanBindings,
1008                         gss_buffer_t inputToken,
1009                         gss_buffer_t outputToken,
1010                         OM_uint32 *smFlags)
1011 {
1012     OM_uint32 major, tmpMinor;
1013     gss_name_t krbInitiator = GSS_C_NO_NAME;
1014     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
1015     struct gss_channel_bindings_struct wireChanBindings = { 0 };
1016
1017     /*
1018      * If we're built with fast reauthentication support, it's valid
1019      * for an initiator to send a GSS reauthentication token as its
1020      * initial context token, causing us to short-circuit the state
1021      * machine and process Kerberos GSS messages instead.
1022      */
1023
1024     ctx->flags |= CTX_FLAG_KRB_REAUTH;
1025
1026     /*
1027      * To avoid an additional round trip, we use GSS channel bindings
1028      * to integrity protect the rest of the initiator exchange. This
1029      * does have the disadvantage of making it impossible for the
1030      * acceptor to ignore application channel bindings, behaviour
1031      * which differs from normal Kerberos and GSS-EAP itself.
1032      */
1033     major = gssEapMakeTokenChannelBindings(minor, ctx,
1034                                            userChanBindings,
1035                                            inputToken,
1036                                            &wireChanBindings);
1037     if (GSS_ERROR(major))
1038         return major;
1039
1040     major = gssAcceptSecContext(minor,
1041                                 &ctx->kerberosCtx,
1042                                 cred->krbCred,
1043                                 inputToken,
1044                                 &wireChanBindings,
1045                                 &krbInitiator,
1046                                 &mech,
1047                                 outputToken,
1048                                 &gssFlags,
1049                                 &timeRec,
1050                                 NULL);
1051     if (major == GSS_S_COMPLETE) {
1052         major = acceptReadyKrb(minor, ctx, cred,
1053                                krbInitiator, mech, timeRec);
1054         if (major == GSS_S_COMPLETE) {
1055             /* Generate acceptor MIC */
1056             GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ACCEPTOR_EXTS);
1057         }
1058         ctx->gssFlags = gssFlags;
1059     } else if (GSS_ERROR(major) &&
1060         (*smFlags & SM_FLAG_INPUT_TOKEN_CRITICAL) == 0) {
1061         /* Fall back to EAP */
1062         gssDeleteSecContext(&tmpMinor, &ctx->kerberosCtx, GSS_C_NO_BUFFER);
1063         ctx->flags &= ~(CTX_FLAG_KRB_REAUTH);
1064         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_INITIAL);
1065     } else {
1066         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_REAUTHENTICATE);
1067     }
1068
1069     major = GSS_S_CONTINUE_NEEDED;
1070
1071     gssReleaseName(&tmpMinor, &krbInitiator);
1072     gss_release_buffer(&tmpMinor, &wireChanBindings.application_data);
1073
1074     return major;
1075 }
1076 #endif /* GSSEAP_ENABLE_REAUTH */