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->mechanismUsed,
  86                              &ctx->initiatorName);
  87     if (GSS_ERROR(major))
  88         return major;
  89
  90     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  91                                   PW_MS_MPPE_SEND_KEY, VENDORPEC_MS, &vp);
  92     if (GSS_ERROR(major)) {
  93         *minor = GSSEAP_KEY_UNAVAILABLE;
  94         return GSS_S_UNAVAILABLE;
  95     }
  96
  97     major = gssEapDeriveRfc3961Key(minor,
  98                                    vp->vp_octets,
  99                                    vp->length,
 100                                    ctx->encryptionType,
 101                                    &ctx->rfc3961Key);
 102     if (GSS_ERROR(major))
 103         return major;
 104
 105     major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 106                                        &ctx->checksumType);
 107     if (GSS_ERROR(major))
 108         return major;
 109
 110     major = sequenceInit(minor,
 111                          &ctx->seqState, ctx->recvSeq,
 112                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 113                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 114                          TRUE);
 115     if (GSS_ERROR(major))
 116         return major;
 117
 118     major = gssEapCreateAttrContext(minor, cred, ctx,
 119                                     &ctx->initiatorName->attrCtx,
 120                                     &ctx->expiryTime);
 121     if (GSS_ERROR(major))
 122         return major;
 123
 124     *minor = 0;
 125     return GSS_S_COMPLETE;
 126 }
 127
 128 static OM_uint32
 129 gssEapSupportedInitiatorExts[] = {
 130 };
 131
 132 static struct gss_eap_itok_map
 133 gssEapAcceptorExtsFlagMap[] = {
 134     { ITOK_TYPE_REAUTH_CREDS, CTX_FLAG_KRB_REAUTH_SUPPORTED },
 135 };
 136
 137 static OM_uint32
 138 eapGssSmAcceptExts(OM_uint32 *minor,
 139                    gss_cred_id_t cred GSSEAP_UNUSED,
 140                    gss_ctx_id_t ctx GSSEAP_UNUSED,
 141                    gss_name_t target GSSEAP_UNUSED,
 142                    gss_OID mech GSSEAP_UNUSED,
 143                    OM_uint32 reqFlags GSSEAP_UNUSED,
 144                    OM_uint32 timeReq GSSEAP_UNUSED,
 145                    gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 146                    gss_buffer_t inputToken,
 147                    gss_buffer_t outputToken,
 148                    OM_uint32 *smFlags GSSEAP_UNUSED)
 149 {
 150     OM_uint32 major;
 151
 152     major = gssEapProcessSupportedExts(minor, inputToken,
 153                                        gssEapAcceptorExtsFlagMap,
 154                                         sizeof(gssEapAcceptorExtsFlagMap) /
 155                                        sizeof(gssEapAcceptorExtsFlagMap[0]),
 156                                        &ctx->flags);
 157     if (GSS_ERROR(major))
 158         return major;
 159
 160     major = gssEapEncodeSupportedExts(minor,
 161                                       gssEapSupportedInitiatorExts,
 162                                       sizeof(gssEapSupportedInitiatorExts) /
 163                                         sizeof(gssEapSupportedInitiatorExts[0]),
 164                                       outputToken);
 165     if (GSS_ERROR(major))
 166         return major;
 167
 168     return GSS_S_CONTINUE_NEEDED;
 169 }
 170
 171 static OM_uint32
 172 eapGssSmAcceptAcceptorName(OM_uint32 *minor,
 173                            gss_cred_id_t cred GSSEAP_UNUSED,
 174                            gss_ctx_id_t ctx,
 175                            gss_name_t target GSSEAP_UNUSED,
 176                            gss_OID mech GSSEAP_UNUSED,
 177                            OM_uint32 reqFlags GSSEAP_UNUSED,
 178                            OM_uint32 timeReq GSSEAP_UNUSED,
 179                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 180                            gss_buffer_t inputToken GSSEAP_UNUSED,
 181                            gss_buffer_t outputToken,
 182                            OM_uint32 *smFlags GSSEAP_UNUSED)
 183 {
 184     OM_uint32 major;
 185
 186     /* XXX TODO import and validate name from inputToken */
 187
 188     if (ctx->acceptorName != GSS_C_NO_NAME) {
 189         /* Send desired target name to acceptor */
 190         major = gssEapDisplayName(minor, ctx->acceptorName,
 191                                   outputToken, NULL);
 192         if (GSS_ERROR(major))
 193             return major;
 194     }
 195
 196     return GSS_S_CONTINUE_NEEDED;
 197 }
 198
 199 #ifdef GSSEAP_DEBUG
 200 static OM_uint32
 201 eapGssSmAcceptVendorInfo(OM_uint32 *minor,
 202                          gss_cred_id_t cred GSSEAP_UNUSED,
 203                          gss_ctx_id_t ctx GSSEAP_UNUSED,
 204                          gss_name_t target GSSEAP_UNUSED,
 205                          gss_OID mech GSSEAP_UNUSED,
 206                          OM_uint32 reqFlags GSSEAP_UNUSED,
 207                          OM_uint32 timeReq GSSEAP_UNUSED,
 208                          gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 209                          gss_buffer_t inputToken,
 210                          gss_buffer_t outputToken GSSEAP_UNUSED,
 211                          OM_uint32 *smFlags GSSEAP_UNUSED)
 212 {
 213     fprintf(stderr, "GSS-EAP: vendor: %.*s\n",
 214             (int)inputToken->length, (char *)inputToken->value);
 215
 216     *minor = 0;
 217     return GSS_S_CONTINUE_NEEDED;
 218 }
 219 #endif
 220
 221
 222 /*
 223  * Emit a identity EAP request to force the initiator (peer) to identify
 224  * itself.
 225  */
 226 static OM_uint32
 227 eapGssSmAcceptIdentity(OM_uint32 *minor,
 228                        gss_cred_id_t cred,
 229                        gss_ctx_id_t ctx,
 230                        gss_name_t target GSSEAP_UNUSED,
 231                        gss_OID mech GSSEAP_UNUSED,
 232                        OM_uint32 reqFlags GSSEAP_UNUSED,
 233                        OM_uint32 timeReq GSSEAP_UNUSED,
 234                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 235                        gss_buffer_t inputToken,
 236                        gss_buffer_t outputToken,
 237                        OM_uint32 *smFlags)
 238 {
 239     OM_uint32 major;
 240     struct wpabuf *reqData;
 241     gss_buffer_desc pktBuffer;
 242
 243     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 244         *minor = GSSEAP_CRED_MECH_MISMATCH;
 245         return GSS_S_BAD_MECH;
 246     }
 247
 248     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
 249         *minor = GSSEAP_WRONG_SIZE;
 250         return GSS_S_DEFECTIVE_TOKEN;
 251     }
 252
 253     reqData = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY, 0,
 254                             EAP_CODE_REQUEST, 0);
 255     if (reqData == NULL) {
 256         *minor = ENOMEM;
 257         return GSS_S_FAILURE;
 258     }
 259
 260     pktBuffer.length = wpabuf_len(reqData);
 261     pktBuffer.value = (void *)wpabuf_head(reqData);
 262
 263     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 264     if (GSS_ERROR(major))
 265         return major;
 266
 267     wpabuf_free(reqData);
 268
 269     GSSEAP_SM_TRANSITION_NEXT(ctx);
 270
 271     *minor = 0;
 272     *smFlags |= SM_FLAG_SEND_TOKEN | SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 273
 274     return GSS_S_CONTINUE_NEEDED;
 275 }
 276
 277 /*
 278  * Returns TRUE if the input token contains an EAP identity response.
 279  */
 280 static int
 281 isIdentityResponseP(gss_buffer_t inputToken)
 282 {
 283     struct wpabuf respData;
 284
 285     wpabuf_set(&respData, inputToken->value, inputToken->length);
 286
 287     return (eap_get_type(&respData) == EAP_TYPE_IDENTITY);
 288 }
 289
 290 /*
 291  * Save the asserted initiator identity from the EAP identity response.
 292  */
 293 static OM_uint32
 294 importInitiatorIdentity(OM_uint32 *minor,
 295                         gss_ctx_id_t ctx,
 296                         gss_buffer_t inputToken)
 297 {
 298     OM_uint32 tmpMinor;
 299     struct wpabuf respData;
 300     const unsigned char *pos;
 301     size_t len;
 302     gss_buffer_desc nameBuf;
 303
 304     wpabuf_set(&respData, inputToken->value, inputToken->length);
 305
 306     pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY,
 307                            &respData, &len);
 308     if (pos == NULL) {
 309         *minor = GSSEAP_PEER_BAD_MESSAGE;
 310         return GSS_S_DEFECTIVE_TOKEN;
 311     }
 312
 313     nameBuf.value = (void *)pos;
 314     nameBuf.length = len;
 315
 316     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
 317
 318     return gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
 319                             ctx->mechanismUsed, &ctx->initiatorName);
 320 }
 321
 322 /*
 323  * Pass the asserted initiator identity to the authentication server.
 324  */
 325 static OM_uint32
 326 setInitiatorIdentity(OM_uint32 *minor,
 327                      gss_ctx_id_t ctx,
 328                      VALUE_PAIR **vps)
 329 {
 330     OM_uint32 major, tmpMinor;
 331     gss_buffer_desc nameBuf;
 332
 333     /*
 334      * We should have got an EAP identity response, but if we didn't, then
 335      * we will just avoid sending User-Name. Note that radsecproxy requires
 336      * User-Name to be sent on every request (presumably so it can remain
 337      * stateless).
 338      */
 339     if (ctx->initiatorName != GSS_C_NO_NAME) {
 340         major = gssEapDisplayName(minor, ctx->initiatorName, &nameBuf, NULL);
 341         if (GSS_ERROR(major))
 342             return major;
 343
 344         major = gssEapRadiusAddAvp(minor, vps, PW_USER_NAME, 0, &nameBuf);
 345         if (GSS_ERROR(major))
 346             return major;
 347
 348         gss_release_buffer(&tmpMinor, &nameBuf);
 349     }
 350
 351     *minor = 0;
 352     return GSS_S_COMPLETE;
 353 }
 354
 355 /*
 356  * Pass the asserted acceptor identity to the authentication server.
 357  */
 358 static OM_uint32
 359 setAcceptorIdentity(OM_uint32 *minor,
 360                     gss_ctx_id_t ctx,
 361                     VALUE_PAIR **vps)
 362 {
 363     OM_uint32 major;
 364     gss_buffer_desc nameBuf;
 365     krb5_context krbContext = NULL;
 366     krb5_principal krbPrinc;
 367     struct rs_context *rc = ctx->acceptorCtx.radContext;
 368
 369     assert(rc != NULL);
 370
 371     if (ctx->acceptorName == GSS_C_NO_NAME) {
 372         *minor = 0;
 373         return GSS_S_COMPLETE;
 374     }
 375
 376     if ((ctx->acceptorName->flags & NAME_FLAG_SERVICE) == 0) {
 377         *minor = GSSEAP_BAD_SERVICE_NAME;
 378         return GSS_S_BAD_NAME;
 379     }
 380
 381     GSSEAP_KRB_INIT(&krbContext);
 382
 383     krbPrinc = ctx->acceptorName->krbPrincipal;
 384     assert(krbPrinc != NULL);
 385     assert(KRB_PRINC_LENGTH(krbPrinc) >= 2);
 386
 387     /* Acceptor-Service-Name */
 388     krbPrincComponentToGssBuffer(krbPrinc, 0, &nameBuf);
 389
 390     major = gssEapRadiusAddAvp(minor, vps,
 391                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 392                                VENDORPEC_UKERNA,
 393                                &nameBuf);
 394     if (GSS_ERROR(major))
 395         return major;
 396
 397     /* Acceptor-Host-Name */
 398     krbPrincComponentToGssBuffer(krbPrinc, 1, &nameBuf);
 399
 400     major = gssEapRadiusAddAvp(minor, vps,
 401                                PW_GSS_ACCEPTOR_HOST_NAME,
 402                                VENDORPEC_UKERNA,
 403                                &nameBuf);
 404     if (GSS_ERROR(major))
 405         return major;
 406
 407     if (KRB_PRINC_LENGTH(krbPrinc) > 2) {
 408         /* Acceptor-Service-Specific */
 409         krb5_principal_data ssiPrinc = *krbPrinc;
 410         char *ssi;
 411
 412         KRB_PRINC_LENGTH(&ssiPrinc) -= 2;
 413         KRB_PRINC_NAME(&ssiPrinc) += 2;
 414
 415         *minor = krb5_unparse_name_flags(krbContext, &ssiPrinc,
 416                                          KRB5_PRINCIPAL_UNPARSE_NO_REALM, &ssi);
 417         if (*minor != 0)
 418             return GSS_S_FAILURE;
 419
 420         nameBuf.value = ssi;
 421         nameBuf.length = strlen(ssi);
 422
 423         major = gssEapRadiusAddAvp(minor, vps,
 424                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFIC,
 425                                    VENDORPEC_UKERNA,
 426                                    &nameBuf);
 427
 428         if (GSS_ERROR(major)) {
 429             krb5_free_unparsed_name(krbContext, ssi);
 430             return major;
 431         }
 432         krb5_free_unparsed_name(krbContext, ssi);
 433     }
 434
 435     krbPrincRealmToGssBuffer(krbPrinc, &nameBuf);
 436     if (nameBuf.length != 0) {
 437         /* Acceptor-Realm-Name */
 438         major = gssEapRadiusAddAvp(minor, vps,
 439                                    PW_GSS_ACCEPTOR_REALM_NAME,
 440                                    VENDORPEC_UKERNA,
 441                                    &nameBuf);
 442         if (GSS_ERROR(major))
 443             return major;
 444     }
 445
 446     *minor = 0;
 447     return GSS_S_COMPLETE;
 448 }
 449
 450 /*
 451  * Allocate a RadSec handle
 452  */
 453 static OM_uint32
 454 createRadiusHandle(OM_uint32 *minor,
 455                    gss_cred_id_t cred,
 456                    gss_ctx_id_t ctx)
 457 {
 458     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 459     const char *configFile = RS_CONFIG_FILE;
 460     const char *configStanza = "gss-eap";
 461     struct rs_alloc_scheme ralloc;
 462     struct rs_error *err;
 463
 464     assert(actx->radContext == NULL);
 465     assert(actx->radConn == NULL);
 466
 467     if (rs_context_create(&actx->radContext, RS_DICT_FILE) != 0) {
 468         *minor = GSSEAP_RADSEC_CONTEXT_FAILURE;
 469         return GSS_S_FAILURE;
 470     }
 471
 472     if (cred->radiusConfigFile != NULL)
 473         configFile = cred->radiusConfigFile;
 474     if (cred->radiusConfigStanza != NULL)
 475         configStanza = cred->radiusConfigStanza;
 476
 477     ralloc.calloc  = GSSEAP_CALLOC;
 478     ralloc.malloc  = GSSEAP_MALLOC;
 479     ralloc.free    = GSSEAP_FREE;
 480     ralloc.realloc = GSSEAP_REALLOC;
 481
 482     rs_context_set_alloc_scheme(actx->radContext, &ralloc);
 483
 484     if (rs_context_read_config(actx->radContext, configFile) != 0) {
 485         err = rs_err_ctx_pop(actx->radContext);
 486         goto fail;
 487     }
 488
 489     if (rs_conn_create(actx->radContext, &actx->radConn, configStanza) != 0) {
 490         err = rs_err_conn_pop(actx->radConn);
 491         goto fail;
 492     }
 493
 494     if (actx->radServer != NULL) {
 495         if (rs_conn_select_peer(actx->radConn, actx->radServer) != 0) {
 496             err = rs_err_conn_pop(actx->radConn);
 497             goto fail;
 498         }
 499     }
 500
 501     *minor = 0;
 502     return GSS_S_COMPLETE;
 503
 504 fail:
 505     return gssEapRadiusMapError(minor, err);
 506 }
 507
 508 /*
 509  * Process a EAP response from the initiator.
 510  */
 511 static OM_uint32
 512 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 513                            gss_cred_id_t cred,
 514                            gss_ctx_id_t ctx,
 515                            gss_name_t target GSSEAP_UNUSED,
 516                            gss_OID mech GSSEAP_UNUSED,
 517                            OM_uint32 reqFlags GSSEAP_UNUSED,
 518                            OM_uint32 timeReq GSSEAP_UNUSED,
 519                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 520                            gss_buffer_t inputToken,
 521                            gss_buffer_t outputToken,
 522                            OM_uint32 *smFlags)
 523 {
 524     OM_uint32 major, tmpMinor;
 525     struct rs_connection *rconn;
 526     struct rs_request *request = NULL;
 527     struct rs_packet *req = NULL, *resp = NULL;
 528     struct radius_packet *frreq, *frresp;
 529
 530     if (ctx->acceptorCtx.radContext == NULL) {
 531         /* May be NULL from an imported partial context */
 532         major = createRadiusHandle(minor, cred, ctx);
 533         if (GSS_ERROR(major))
 534             goto cleanup;
 535     }
 536
 537     if (isIdentityResponseP(inputToken)) {
 538         major = importInitiatorIdentity(minor, ctx, inputToken);
 539         if (GSS_ERROR(major))
 540             return major;
 541     }
 542
 543     rconn = ctx->acceptorCtx.radConn;
 544
 545     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 546         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 547         goto cleanup;
 548     }
 549     frreq = rs_packet_frpkt(req);
 550
 551     major = setInitiatorIdentity(minor, ctx, &frreq->vps);
 552     if (GSS_ERROR(major))
 553         goto cleanup;
 554
 555     major = setAcceptorIdentity(minor, ctx, &frreq->vps);
 556     if (GSS_ERROR(major))
 557         goto cleanup;
 558
 559     major = gssEapRadiusAddAvp(minor, &frreq->vps,
 560                                PW_EAP_MESSAGE, 0, inputToken);
 561     if (GSS_ERROR(major))
 562         goto cleanup;
 563
 564     if (ctx->acceptorCtx.state.length != 0) {
 565         major = gssEapRadiusAddAvp(minor, &frreq->vps, PW_STATE, 0,
 566                                    &ctx->acceptorCtx.state);
 567         if (GSS_ERROR(major))
 568             goto cleanup;
 569
 570         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 571     }
 572
 573     if (rs_request_create(rconn, &request) != 0) {
 574         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 575         goto cleanup;
 576     }
 577
 578     rs_request_add_reqpkt(request, req);
 579     req = NULL;
 580
 581     if (rs_request_send(request, &resp) != 0) {
 582         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 583         goto cleanup;
 584     }
 585
 586     assert(resp != NULL);
 587
 588     frresp = rs_packet_frpkt(resp);
 589     switch (frresp->code) {
 590     case PW_ACCESS_CHALLENGE:
 591     case PW_AUTHENTICATION_ACK:
 592         break;
 593     case PW_AUTHENTICATION_REJECT:
 594         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 595         major = GSS_S_DEFECTIVE_CREDENTIAL;
 596         goto cleanup;
 597         break;
 598     default:
 599         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 600         major = GSS_S_FAILURE;
 601         goto cleanup;
 602         break;
 603     }
 604
 605     major = gssEapRadiusGetAvp(minor, frresp->vps, PW_EAP_MESSAGE, 0,
 606                                outputToken, TRUE);
 607     if (major == GSS_S_UNAVAILABLE && frresp->code == PW_ACCESS_CHALLENGE) {
 608         *minor = GSSEAP_MISSING_EAP_REQUEST;
 609         major = GSS_S_DEFECTIVE_TOKEN;
 610         goto cleanup;
 611     } else if (GSS_ERROR(major))
 612         goto cleanup;
 613
 614     if (frresp->code == PW_ACCESS_CHALLENGE) {
 615         major = gssEapRadiusGetAvp(minor, frresp->vps, PW_STATE, 0,
 616                                    &ctx->acceptorCtx.state, TRUE);
 617         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 618             goto cleanup;
 619     } else {
 620         ctx->acceptorCtx.vps = frresp->vps;
 621         frresp->vps = NULL;
 622
 623         major = acceptReadyEap(minor, ctx, cred);
 624         if (GSS_ERROR(major))
 625             goto cleanup;
 626
 627         GSSEAP_SM_TRANSITION_NEXT(ctx);
 628     }
 629
 630     major = GSS_S_CONTINUE_NEEDED;
 631     *minor = 0;
 632     *smFlags |= SM_FLAG_SEND_TOKEN | SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 633
 634 cleanup:
 635     if (request != NULL)
 636         rs_request_destroy(request);
 637     if (req != NULL)
 638         rs_packet_destroy(req);
 639     if (resp != NULL)
 640         rs_packet_destroy(resp);
 641     if (GSSEAP_SM_STATE(ctx) == GSSEAP_STATE_INITIATOR_EXTS) {
 642         assert(major == GSS_S_CONTINUE_NEEDED);
 643
 644         rs_conn_destroy(ctx->acceptorCtx.radConn);
 645         ctx->acceptorCtx.radConn = NULL;
 646     }
 647
 648     return major;
 649 }
 650
 651 static OM_uint32
 652 eapGssSmAcceptGssFlags(OM_uint32 *minor,
 653                        gss_cred_id_t cred GSSEAP_UNUSED,
 654                        gss_ctx_id_t ctx,
 655                        gss_name_t target GSSEAP_UNUSED,
 656                        gss_OID mech GSSEAP_UNUSED,
 657                        OM_uint32 reqFlags GSSEAP_UNUSED,
 658                        OM_uint32 timeReq GSSEAP_UNUSED,
 659                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 660                        gss_buffer_t inputToken,
 661                        gss_buffer_t outputToken GSSEAP_UNUSED,
 662                        OM_uint32 *smFlags GSSEAP_UNUSED)
 663 {
 664     unsigned char *p;
 665     OM_uint32 initiatorGssFlags;
 666
 667     assert((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
 668
 669     if (inputToken->length < 4) {
 670         *minor = GSSEAP_TOK_TRUNC;
 671         return GSS_S_DEFECTIVE_TOKEN;
 672     }
 673
 674     /* allow flags to grow for future expansion */
 675     p = (unsigned char *)inputToken->value + inputToken->length - 4;
 676
 677     initiatorGssFlags = load_uint32_be(p);
 678     initiatorGssFlags &= GSSEAP_WIRE_FLAGS_MASK;
 679
 680     ctx->gssFlags |= initiatorGssFlags;
 681
 682     return GSS_S_CONTINUE_NEEDED;
 683 }
 684
 685 static OM_uint32
 686 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 687                                  gss_cred_id_t cred GSSEAP_UNUSED,
 688                                  gss_ctx_id_t ctx,
 689                                  gss_name_t target GSSEAP_UNUSED,
 690                                  gss_OID mech GSSEAP_UNUSED,
 691                                  OM_uint32 reqFlags GSSEAP_UNUSED,
 692                                  OM_uint32 timeReq GSSEAP_UNUSED,
 693                                  gss_channel_bindings_t chanBindings,
 694                                  gss_buffer_t inputToken,
 695                                  gss_buffer_t outputToken GSSEAP_UNUSED,
 696                                  OM_uint32 *smFlags GSSEAP_UNUSED)
 697 {
 698     OM_uint32 major, tmpMinor;
 699     gss_iov_buffer_desc iov[2];
 700
 701     assert((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
 702
 703     iov[0].type = GSS_IOV_BUFFER_TYPE_DATA | GSS_IOV_BUFFER_FLAG_ALLOCATE;
 704     iov[0].buffer.length = 0;
 705     iov[0].buffer.value = NULL;
 706
 707     iov[1].type = GSS_IOV_BUFFER_TYPE_STREAM;
 708     iov[1].buffer = *inputToken;
 709
 710     major = gssEapUnwrapOrVerifyMIC(minor, ctx, NULL, NULL,
 711                                     iov, 2, TOK_TYPE_WRAP);
 712     if (GSS_ERROR(major))
 713         return major;
 714
 715     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS &&
 716         !bufferEqual(&iov[0].buffer, &chanBindings->application_data)) {
 717         major = GSS_S_BAD_BINDINGS;
 718         *minor = GSSEAP_BINDINGS_MISMATCH;
 719     } else {
 720         major = GSS_S_CONTINUE_NEEDED;
 721         *minor = 0;
 722     }
 723
 724     gss_release_buffer(&tmpMinor, &iov[0].buffer);
 725
 726     return major;
 727 }
 728
 729 #ifdef GSSEAP_ENABLE_REAUTH
 730 static OM_uint32
 731 eapGssSmAcceptReauthCreds(OM_uint32 *minor,
 732                           gss_cred_id_t cred,
 733                           gss_ctx_id_t ctx,
 734                           gss_name_t target GSSEAP_UNUSED,
 735                           gss_OID mech GSSEAP_UNUSED,
 736                           OM_uint32 reqFlags GSSEAP_UNUSED,
 737                           OM_uint32 timeReq GSSEAP_UNUSED,
 738                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 739                           gss_buffer_t inputToken GSSEAP_UNUSED,
 740                           gss_buffer_t outputToken,
 741                           OM_uint32 *smFlags GSSEAP_UNUSED)
 742 {
 743     OM_uint32 major;
 744
 745     /*
 746      * If we're built with fast reauthentication enabled, then
 747      * fabricate a ticket from the initiator to ourselves.
 748      */
 749     if (ctx->flags & CTX_FLAG_KRB_REAUTH_SUPPORTED)
 750         major = gssEapMakeReauthCreds(minor, ctx, cred, outputToken);
 751     else
 752         major = GSS_S_UNAVAILABLE;
 753
 754     if (major == GSS_S_UNAVAILABLE)
 755         major = GSS_S_COMPLETE;
 756
 757     return GSS_ERROR(major) ? major : GSS_S_CONTINUE_NEEDED;
 758 }
 759 #endif
 760
 761 static OM_uint32
 762 eapGssSmAcceptInitiatorMIC(OM_uint32 *minor,
 763                            gss_cred_id_t cred GSSEAP_UNUSED,
 764                            gss_ctx_id_t ctx,
 765                            gss_name_t target GSSEAP_UNUSED,
 766                            gss_OID mech GSSEAP_UNUSED,
 767                            OM_uint32 reqFlags GSSEAP_UNUSED,
 768                            OM_uint32 timeReq GSSEAP_UNUSED,
 769                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 770                            gss_buffer_t inputToken,
 771                            gss_buffer_t outputToken GSSEAP_UNUSED,
 772                            OM_uint32 *smFlags GSSEAP_UNUSED)
 773 {
 774     OM_uint32 major;
 775
 776     assert((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
 777
 778     major = gssEapVerifyConversationMIC(minor, ctx, inputToken);
 779     if (GSS_ERROR(major))
 780         return major;
 781
 782     GSSEAP_SM_TRANSITION_NEXT(ctx);
 783
 784     *minor = 0;
 785
 786     return GSS_S_CONTINUE_NEEDED;
 787 }
 788
 789 static OM_uint32
 790 eapGssSmAcceptAcceptorMIC(OM_uint32 *minor,
 791                           gss_cred_id_t cred GSSEAP_UNUSED,
 792                           gss_ctx_id_t ctx,
 793                           gss_name_t target GSSEAP_UNUSED,
 794                           gss_OID mech GSSEAP_UNUSED,
 795                           OM_uint32 reqFlags GSSEAP_UNUSED,
 796                           OM_uint32 timeReq GSSEAP_UNUSED,
 797                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 798                           gss_buffer_t inputToken GSSEAP_UNUSED,
 799                           gss_buffer_t outputToken,
 800                           OM_uint32 *smFlags)
 801 {
 802     OM_uint32 major;
 803
 804     major = gssEapGetConversationMIC(minor, ctx, outputToken);
 805     if (GSS_ERROR(major))
 806         return major;
 807
 808     GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 809
 810     *minor = 0;
 811     *smFlags |= SM_FLAG_SEND_TOKEN | SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 812
 813     return GSS_S_COMPLETE;
 814 }
 815
 816 /*
 817  * Acceptor state machine.
 818  */
 819 static struct gss_eap_sm eapGssAcceptorSm[] = {
 820 #ifdef GSSEAP_ENABLE_REAUTH
 821     {
 822         ITOK_TYPE_REAUTH_REQ,
 823         ITOK_TYPE_REAUTH_RESP,
 824         GSSEAP_STATE_INITIAL | GSSEAP_STATE_REAUTHENTICATE,
 825         0,
 826         eapGssSmAcceptGssReauth,
 827     },
 828 #endif
 829     {
 830         ITOK_TYPE_ACCEPTOR_NAME_REQ,
 831         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 832         GSSEAP_STATE_INITIAL,
 833         0,
 834         eapGssSmAcceptAcceptorName
 835     },
 836     {
 837         ITOK_TYPE_SUPPORTED_ACCEPTOR_EXTS,
 838         ITOK_TYPE_SUPPORTED_INITIATOR_EXTS,
 839         GSSEAP_STATE_INITIAL,
 840         0,
 841         eapGssSmAcceptExts,
 842     },
 843 #ifdef GSSEAP_DEBUG
 844     {
 845         ITOK_TYPE_VENDOR_INFO,
 846         ITOK_TYPE_NONE,
 847         GSSEAP_STATE_INITIAL,
 848         0,
 849         eapGssSmAcceptVendorInfo,
 850     },
 851 #endif
 852     {
 853         ITOK_TYPE_NONE,
 854         ITOK_TYPE_EAP_REQ,
 855         GSSEAP_STATE_INITIAL,
 856         SM_ITOK_FLAG_REQUIRED,
 857         eapGssSmAcceptIdentity,
 858     },
 859     {
 860         ITOK_TYPE_EAP_RESP,
 861         ITOK_TYPE_EAP_REQ,
 862         GSSEAP_STATE_AUTHENTICATE,
 863         SM_ITOK_FLAG_REQUIRED,
 864         eapGssSmAcceptAuthenticate
 865     },
 866     {
 867         ITOK_TYPE_GSS_FLAGS,
 868         ITOK_TYPE_NONE,
 869         GSSEAP_STATE_INITIATOR_EXTS,
 870         0,
 871         eapGssSmAcceptGssFlags
 872     },
 873     {
 874         ITOK_TYPE_GSS_CHANNEL_BINDINGS,
 875         ITOK_TYPE_NONE,
 876         GSSEAP_STATE_INITIATOR_EXTS,
 877         0,
 878         eapGssSmAcceptGssChannelBindings,
 879     },
 880     {
 881         ITOK_TYPE_INITIATOR_MIC,
 882         ITOK_TYPE_NONE,
 883         GSSEAP_STATE_INITIATOR_EXTS,
 884         SM_ITOK_FLAG_REQUIRED,
 885         eapGssSmAcceptInitiatorMIC,
 886     },
 887 #ifdef GSSEAP_ENABLE_REAUTH
 888     {
 889         ITOK_TYPE_NONE,
 890         ITOK_TYPE_REAUTH_CREDS,
 891         GSSEAP_STATE_ACCEPTOR_EXTS,
 892         0,
 893         eapGssSmAcceptReauthCreds,
 894     },
 895 #endif
 896     {
 897         ITOK_TYPE_NONE,
 898         ITOK_TYPE_ACCEPTOR_MIC,
 899         GSSEAP_STATE_ACCEPTOR_EXTS,
 900         0,
 901         eapGssSmAcceptAcceptorMIC
 902     },
 903 };
 904
 905 OM_uint32
 906 gss_accept_sec_context(OM_uint32 *minor,
 907                        gss_ctx_id_t *context_handle,
 908                        gss_cred_id_t cred,
 909                        gss_buffer_t input_token,
 910                        gss_channel_bindings_t input_chan_bindings,
 911                        gss_name_t *src_name,
 912                        gss_OID *mech_type,
 913                        gss_buffer_t output_token,
 914                        OM_uint32 *ret_flags,
 915                        OM_uint32 *time_rec,
 916                        gss_cred_id_t *delegated_cred_handle)
 917 {
 918     OM_uint32 major, tmpMinor;
 919     gss_ctx_id_t ctx = *context_handle;
 920
 921     *minor = 0;
 922
 923     output_token->length = 0;
 924     output_token->value = NULL;
 925
 926     if (src_name != NULL)
 927         *src_name = GSS_C_NO_NAME;
 928
 929     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 930         *minor = GSSEAP_TOK_TRUNC;
 931         return GSS_S_DEFECTIVE_TOKEN;
 932     }
 933
 934     if (ctx == GSS_C_NO_CONTEXT) {
 935         major = gssEapAllocContext(minor, &ctx);
 936         if (GSS_ERROR(major))
 937             return major;
 938
 939         *context_handle = ctx;
 940     }
 941
 942     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 943
 944     if (cred == GSS_C_NO_CREDENTIAL) {
 945         if (ctx->defaultCred == GSS_C_NO_CREDENTIAL) {
 946             major = gssEapAcquireCred(minor,
 947                                       GSS_C_NO_NAME,
 948                                       GSS_C_NO_BUFFER,
 949                                       GSS_C_INDEFINITE,
 950                                       GSS_C_NO_OID_SET,
 951                                       GSS_C_ACCEPT,
 952                                       &ctx->defaultCred,
 953                                       NULL,
 954                                       NULL);
 955             if (GSS_ERROR(major))
 956                 goto cleanup;
 957         }
 958
 959         cred = ctx->defaultCred;
 960     }
 961
 962     GSSEAP_MUTEX_LOCK(&cred->mutex);
 963
 964     if (cred->name != GSS_C_NO_NAME) {
 965         major = gssEapDuplicateName(minor, cred->name, &ctx->acceptorName);
 966         if (GSS_ERROR(major))
 967             goto cleanup;
 968     }
 969
 970     major = gssEapSmStep(minor,
 971                          cred,
 972                          ctx,
 973                          GSS_C_NO_NAME,
 974                          GSS_C_NO_OID,
 975                          0,
 976                          GSS_C_INDEFINITE,
 977                          input_chan_bindings,
 978                          input_token,
 979                          output_token,
 980                          eapGssAcceptorSm,
 981                          sizeof(eapGssAcceptorSm) / sizeof(eapGssAcceptorSm[0]));
 982     if (GSS_ERROR(major))
 983         goto cleanup;
 984
 985     if (mech_type != NULL) {
 986         OM_uint32 tmpMajor;
 987
 988         tmpMajor = gssEapCanonicalizeOid(&tmpMinor, ctx->mechanismUsed, 0, mech_type);
 989         if (GSS_ERROR(tmpMajor)) {
 990             major = tmpMajor;
 991             *minor = tmpMinor;
 992             goto cleanup;
 993         }
 994     }
 995     if (ret_flags != NULL)
 996         *ret_flags = ctx->gssFlags;
 997     if (delegated_cred_handle != NULL)
 998         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 999
1000     if (major == GSS_S_COMPLETE) {
1001         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
1002             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
1003             if (GSS_ERROR(major))
1004                 goto cleanup;
1005         }
1006         if (time_rec != NULL) {
1007             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
1008             if (GSS_ERROR(major))
1009                 goto cleanup;
1010         }
1011     }
1012
1013     assert(CTX_IS_ESTABLISHED(ctx) || major == GSS_S_CONTINUE_NEEDED);
1014
1015 cleanup:
1016     if (cred != GSS_C_NO_CREDENTIAL)
1017         GSSEAP_MUTEX_UNLOCK(&cred->mutex);
1018     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
1019
1020     if (GSS_ERROR(major))
1021         gssEapReleaseContext(&tmpMinor, context_handle);
1022
1023     return major;
1024 }
1025
1026 #ifdef GSSEAP_ENABLE_REAUTH
1027 static OM_uint32
1028 acceptReadyKrb(OM_uint32 *minor,
1029                gss_ctx_id_t ctx,
1030                gss_cred_id_t cred,
1031                const gss_name_t initiator,
1032                const gss_OID mech,
1033                OM_uint32 timeRec)
1034 {
1035     OM_uint32 major;
1036
1037     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
1038     if (GSS_ERROR(major))
1039         return major;
1040
1041     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
1042     if (GSS_ERROR(major))
1043         return major;
1044
1045     *minor = 0;
1046     return GSS_S_COMPLETE;
1047 }
1048
1049 static OM_uint32
1050 eapGssSmAcceptGssReauth(OM_uint32 *minor,
1051                         gss_cred_id_t cred,
1052                         gss_ctx_id_t ctx,
1053                         gss_name_t target GSSEAP_UNUSED,
1054                         gss_OID mech,
1055                         OM_uint32 reqFlags GSSEAP_UNUSED,
1056                         OM_uint32 timeReq GSSEAP_UNUSED,
1057                         gss_channel_bindings_t userChanBindings,
1058                         gss_buffer_t inputToken,
1059                         gss_buffer_t outputToken,
1060                         OM_uint32 *smFlags)
1061 {
1062     OM_uint32 major, tmpMinor;
1063     gss_name_t krbInitiator = GSS_C_NO_NAME;
1064     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
1065     struct gss_channel_bindings_struct wireChanBindings = { 0 };
1066
1067     /*
1068      * If we're built with fast reauthentication support, it's valid
1069      * for an initiator to send a GSS reauthentication token as its
1070      * initial context token, causing us to short-circuit the state
1071      * machine and process Kerberos GSS messages instead.
1072      */
1073
1074     ctx->flags |= CTX_FLAG_KRB_REAUTH;
1075
1076     /*
1077      * To avoid an additional round trip, we use GSS channel bindings
1078      * to integrity protect the rest of the initiator exchange. This
1079      * does have the disadvantage of making it impossible for the
1080      * acceptor to ignore application channel bindings, behaviour
1081      * which differs from normal Kerberos and GSS-EAP itself.
1082      */
1083     major = gssEapMakeTokenChannelBindings(minor, ctx,
1084                                            userChanBindings,
1085                                            inputToken,
1086                                            &wireChanBindings);
1087     if (GSS_ERROR(major))
1088         return major;
1089
1090     major = gssAcceptSecContext(minor,
1091                                 &ctx->kerberosCtx,
1092                                 cred->krbCred,
1093                                 inputToken,
1094                                 &wireChanBindings,
1095                                 &krbInitiator,
1096                                 &mech,
1097                                 outputToken,
1098                                 &gssFlags,
1099                                 &timeRec,
1100                                 NULL);
1101     if (major == GSS_S_COMPLETE) {
1102         major = acceptReadyKrb(minor, ctx, cred,
1103                                krbInitiator, mech, timeRec);
1104         if (major == GSS_S_COMPLETE) {
1105             /* Generate acceptor MIC */
1106             GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ACCEPTOR_EXTS);
1107         }
1108         ctx->gssFlags = gssFlags;
1109     } else if (GSS_ERROR(major) &&
1110         (*smFlags & SM_FLAG_INPUT_TOKEN_CRITICAL) == 0) {
1111         /* Fall back to EAP */
1112         gssDeleteSecContext(&tmpMinor, &ctx->kerberosCtx, GSS_C_NO_BUFFER);
1113         ctx->flags &= ~(CTX_FLAG_KRB_REAUTH);
1114         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_INITIAL);
1115     } else {
1116         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_REAUTHENTICATE);
1117     }
1118
1119     major = GSS_S_CONTINUE_NEEDED;
1120
1121     gssReleaseName(&tmpMinor, &krbInitiator);
1122     gss_release_buffer(&tmpMinor, &wireChanBindings.application_data);
1123
1124     return major;
1125 }
1126 #endif /* GSSEAP_ENABLE_REAUTH */