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     rs_const_avp *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 && rs_avp_length(vp) != 0) {
  76         rs_avp_octets_value_byref((rs_avp *)vp,
  77                                   (unsigned char **)&nameBuf.value,
  78                                   &nameBuf.length);
  79     } else {
  80         ctx->gssFlags |= GSS_C_ANON_FLAG;
  81     }
  82
  83     major = gssEapImportName(minor, &nameBuf,
  84                              (ctx->gssFlags & GSS_C_ANON_FLAG) ?
  85                                 GSS_C_NT_ANONYMOUS : GSS_C_NT_USER_NAME,
  86                              ctx->mechanismUsed,
  87                              &ctx->initiatorName);
  88     if (GSS_ERROR(major))
  89         return major;
  90
  91     major = gssEapRadiusGetRawAvp(minor, ctx->acceptorCtx.vps,
  92                                   PW_MS_MPPE_SEND_KEY, VENDORPEC_MICROSOFT, &vp);
  93     if (GSS_ERROR(major)) {
  94         *minor = GSSEAP_KEY_UNAVAILABLE;
  95         return GSS_S_UNAVAILABLE;
  96     }
  97
  98     major = gssEapDeriveRfc3961Key(minor,
  99                                    rs_avp_octets_value_const_ptr(vp),
 100                                    rs_avp_length(vp),
 101                                    ctx->encryptionType,
 102                                    &ctx->rfc3961Key);
 103     if (GSS_ERROR(major))
 104         return major;
 105
 106     major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 107                                        &ctx->checksumType);
 108     if (GSS_ERROR(major))
 109         return major;
 110
 111     major = sequenceInit(minor,
 112                          &ctx->seqState, ctx->recvSeq,
 113                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 114                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 115                          TRUE);
 116     if (GSS_ERROR(major))
 117         return major;
 118
 119     major = gssEapCreateAttrContext(minor, cred, ctx,
 120                                     &ctx->initiatorName->attrCtx,
 121                                     &ctx->expiryTime);
 122     if (GSS_ERROR(major))
 123         return major;
 124
 125     if (ctx->expiryTime != 0 && ctx->expiryTime < time(NULL)) {
 126         *minor = GSSEAP_CRED_EXPIRED;
 127         return GSS_S_CREDENTIALS_EXPIRED;
 128     }
 129
 130     *minor = 0;
 131     return GSS_S_COMPLETE;
 132 }
 133
 134 static OM_uint32
 135 eapGssSmAcceptAcceptorName(OM_uint32 *minor,
 136                            gss_cred_id_t cred GSSEAP_UNUSED,
 137                            gss_ctx_id_t ctx,
 138                            gss_name_t target GSSEAP_UNUSED,
 139                            gss_OID mech GSSEAP_UNUSED,
 140                            OM_uint32 reqFlags GSSEAP_UNUSED,
 141                            OM_uint32 timeReq GSSEAP_UNUSED,
 142                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 143                            gss_buffer_t inputToken GSSEAP_UNUSED,
 144                            gss_buffer_t outputToken,
 145                            OM_uint32 *smFlags GSSEAP_UNUSED)
 146 {
 147     OM_uint32 major;
 148
 149     /* XXX TODO import and validate name from inputToken */
 150
 151     if (ctx->acceptorName != GSS_C_NO_NAME) {
 152         /* Send desired target name to acceptor */
 153         major = gssEapDisplayName(minor, ctx->acceptorName,
 154                                   outputToken, NULL);
 155         if (GSS_ERROR(major))
 156             return major;
 157     }
 158
 159     return GSS_S_CONTINUE_NEEDED;
 160 }
 161
 162 #ifdef GSSEAP_DEBUG
 163 static OM_uint32
 164 eapGssSmAcceptVendorInfo(OM_uint32 *minor,
 165                          gss_cred_id_t cred GSSEAP_UNUSED,
 166                          gss_ctx_id_t ctx GSSEAP_UNUSED,
 167                          gss_name_t target GSSEAP_UNUSED,
 168                          gss_OID mech GSSEAP_UNUSED,
 169                          OM_uint32 reqFlags GSSEAP_UNUSED,
 170                          OM_uint32 timeReq GSSEAP_UNUSED,
 171                          gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 172                          gss_buffer_t inputToken,
 173                          gss_buffer_t outputToken GSSEAP_UNUSED,
 174                          OM_uint32 *smFlags GSSEAP_UNUSED)
 175 {
 176     fprintf(stderr, "GSS-EAP: vendor: %.*s\n",
 177             (int)inputToken->length, (char *)inputToken->value);
 178
 179     *minor = 0;
 180     return GSS_S_CONTINUE_NEEDED;
 181 }
 182 #endif
 183
 184
 185 /*
 186  * Emit a identity EAP request to force the initiator (peer) to identify
 187  * itself.
 188  */
 189 static OM_uint32
 190 eapGssSmAcceptIdentity(OM_uint32 *minor,
 191                        gss_cred_id_t cred,
 192                        gss_ctx_id_t ctx,
 193                        gss_name_t target GSSEAP_UNUSED,
 194                        gss_OID mech GSSEAP_UNUSED,
 195                        OM_uint32 reqFlags GSSEAP_UNUSED,
 196                        OM_uint32 timeReq GSSEAP_UNUSED,
 197                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 198                        gss_buffer_t inputToken,
 199                        gss_buffer_t outputToken,
 200                        OM_uint32 *smFlags)
 201 {
 202     OM_uint32 major;
 203     struct wpabuf *reqData;
 204     gss_buffer_desc pktBuffer;
 205
 206     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 207         *minor = GSSEAP_CRED_MECH_MISMATCH;
 208         return GSS_S_BAD_MECH;
 209     }
 210
 211     if (inputToken != GSS_C_NO_BUFFER && inputToken->length != 0) {
 212         *minor = GSSEAP_WRONG_SIZE;
 213         return GSS_S_DEFECTIVE_TOKEN;
 214     }
 215
 216     reqData = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY, 0,
 217                             EAP_CODE_REQUEST, 0);
 218     if (reqData == NULL) {
 219         *minor = ENOMEM;
 220         return GSS_S_FAILURE;
 221     }
 222
 223     pktBuffer.length = wpabuf_len(reqData);
 224     pktBuffer.value = (void *)wpabuf_head(reqData);
 225
 226     major = duplicateBuffer(minor, &pktBuffer, outputToken);
 227     if (GSS_ERROR(major))
 228         return major;
 229
 230     wpabuf_free(reqData);
 231
 232     GSSEAP_SM_TRANSITION_NEXT(ctx);
 233
 234     *minor = 0;
 235     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 236
 237     return GSS_S_CONTINUE_NEEDED;
 238 }
 239
 240 /*
 241  * Returns TRUE if the input token contains an EAP identity response.
 242  */
 243 static int
 244 isIdentityResponseP(gss_buffer_t inputToken)
 245 {
 246     struct wpabuf respData;
 247
 248     wpabuf_set(&respData, inputToken->value, inputToken->length);
 249
 250     return (eap_get_type(&respData) == EAP_TYPE_IDENTITY);
 251 }
 252
 253 /*
 254  * Save the asserted initiator identity from the EAP identity response.
 255  */
 256 static OM_uint32
 257 importInitiatorIdentity(OM_uint32 *minor,
 258                         gss_ctx_id_t ctx,
 259                         gss_buffer_t inputToken)
 260 {
 261     OM_uint32 tmpMinor;
 262     struct wpabuf respData;
 263     const unsigned char *pos;
 264     size_t len;
 265     gss_buffer_desc nameBuf;
 266
 267     wpabuf_set(&respData, inputToken->value, inputToken->length);
 268
 269     pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IDENTITY,
 270                            &respData, &len);
 271     if (pos == NULL) {
 272         *minor = GSSEAP_PEER_BAD_MESSAGE;
 273         return GSS_S_DEFECTIVE_TOKEN;
 274     }
 275
 276     nameBuf.value = (void *)pos;
 277     nameBuf.length = len;
 278
 279     gssEapReleaseName(&tmpMinor, &ctx->initiatorName);
 280
 281     return gssEapImportName(minor, &nameBuf, GSS_C_NT_USER_NAME,
 282                             ctx->mechanismUsed, &ctx->initiatorName);
 283 }
 284
 285 /*
 286  * Pass the asserted initiator identity to the authentication server.
 287  */
 288 static OM_uint32
 289 setInitiatorIdentity(OM_uint32 *minor,
 290                      gss_ctx_id_t ctx,
 291                      struct rs_packet *req)
 292 {
 293     OM_uint32 major, tmpMinor;
 294     gss_buffer_desc nameBuf;
 295
 296     /*
 297      * We should have got an EAP identity response, but if we didn't, then
 298      * we will just avoid sending User-Name. Note that radsecproxy requires
 299      * User-Name to be sent on every request (presumably so it can remain
 300      * stateless).
 301      */
 302     if (ctx->initiatorName != GSS_C_NO_NAME) {
 303         major = gssEapDisplayName(minor, ctx->initiatorName, &nameBuf, NULL);
 304         if (GSS_ERROR(major))
 305             return major;
 306
 307         major = gssEapRadiusAddAvp(minor, req, PW_USER_NAME, 0, &nameBuf);
 308         if (GSS_ERROR(major))
 309             return major;
 310
 311         gss_release_buffer(&tmpMinor, &nameBuf);
 312     }
 313
 314     *minor = 0;
 315     return GSS_S_COMPLETE;
 316 }
 317
 318 /*
 319  * Pass the asserted acceptor identity to the authentication server.
 320  */
 321 static OM_uint32
 322 setAcceptorIdentity(OM_uint32 *minor,
 323                     gss_ctx_id_t ctx,
 324                     struct rs_packet *req)
 325 {
 326     OM_uint32 major;
 327     gss_buffer_desc nameBuf;
 328     krb5_context krbContext = NULL;
 329     krb5_principal krbPrinc;
 330     struct rs_context *rc = ctx->acceptorCtx.radContext;
 331
 332     GSSEAP_ASSERT(rc != NULL);
 333
 334     if (ctx->acceptorName == GSS_C_NO_NAME) {
 335         *minor = 0;
 336         return GSS_S_COMPLETE;
 337     }
 338
 339     if ((ctx->acceptorName->flags & NAME_FLAG_SERVICE) == 0) {
 340         *minor = GSSEAP_BAD_SERVICE_NAME;
 341         return GSS_S_BAD_NAME;
 342     }
 343
 344     GSSEAP_KRB_INIT(&krbContext);
 345
 346     krbPrinc = ctx->acceptorName->krbPrincipal;
 347     GSSEAP_ASSERT(krbPrinc != NULL);
 348     GSSEAP_ASSERT(KRB_PRINC_LENGTH(krbPrinc) >= 2);
 349
 350     /* Acceptor-Service-Name */
 351     krbPrincComponentToGssBuffer(krbPrinc, 0, &nameBuf);
 352
 353     major = gssEapRadiusAddAvp(minor, req,
 354                                PW_GSS_ACCEPTOR_SERVICE_NAME,
 355                                0,
 356                                &nameBuf);
 357     if (GSS_ERROR(major))
 358         return major;
 359
 360     /* Acceptor-Host-Name */
 361     krbPrincComponentToGssBuffer(krbPrinc, 1, &nameBuf);
 362
 363     major = gssEapRadiusAddAvp(minor, req,
 364                                PW_GSS_ACCEPTOR_HOST_NAME,
 365                                0,
 366                                &nameBuf);
 367     if (GSS_ERROR(major))
 368         return major;
 369
 370     if (KRB_PRINC_LENGTH(krbPrinc) > 2) {
 371         /* Acceptor-Service-Specific */
 372         krb5_principal_data ssiPrinc = *krbPrinc;
 373         char *ssi;
 374
 375         KRB_PRINC_LENGTH(&ssiPrinc) -= 2;
 376         KRB_PRINC_NAME(&ssiPrinc) += 2;
 377
 378         *minor = krb5_unparse_name_flags(krbContext, &ssiPrinc,
 379                                          KRB5_PRINCIPAL_UNPARSE_NO_REALM, &ssi);
 380         if (*minor != 0)
 381             return GSS_S_FAILURE;
 382
 383         nameBuf.value = ssi;
 384         nameBuf.length = strlen(ssi);
 385
 386         major = gssEapRadiusAddAvp(minor, req,
 387                                    PW_GSS_ACCEPTOR_SERVICE_SPECIFICS,
 388                                    0,
 389                                    &nameBuf);
 390
 391         if (GSS_ERROR(major)) {
 392             krb5_free_unparsed_name(krbContext, ssi);
 393             return major;
 394         }
 395         krb5_free_unparsed_name(krbContext, ssi);
 396     }
 397
 398     krbPrincRealmToGssBuffer(krbPrinc, &nameBuf);
 399     if (nameBuf.length != 0) {
 400         /* Acceptor-Realm-Name */
 401         major = gssEapRadiusAddAvp(minor, req,
 402                                    PW_GSS_ACCEPTOR_REALM_NAME,
 403                                    0,
 404                                    &nameBuf);
 405         if (GSS_ERROR(major))
 406             return major;
 407     }
 408
 409     *minor = 0;
 410     return GSS_S_COMPLETE;
 411 }
 412
 413 /*
 414  * Allocate a RadSec handle
 415  */
 416 static OM_uint32
 417 createRadiusHandle(OM_uint32 *minor,
 418                    gss_cred_id_t cred,
 419                    gss_ctx_id_t ctx)
 420 {
 421     struct gss_eap_acceptor_ctx *actx = &ctx->acceptorCtx;
 422     struct rs_error *err;
 423     const char *configStanza = "gss-eap";
 424     OM_uint32 major;
 425
 426     GSSEAP_ASSERT(actx->radContext == NULL);
 427     GSSEAP_ASSERT(actx->radConn == NULL);
 428     GSSEAP_ASSERT(cred != GSS_C_NO_CREDENTIAL);
 429
 430     major = gssEapCreateRadiusContext(minor, cred, &actx->radContext);
 431     if (GSS_ERROR(major))
 432         return major;
 433
 434     if (cred->radiusConfigStanza.value != NULL)
 435         configStanza = (const char *)cred->radiusConfigStanza.value;
 436
 437     if (rs_conn_create(actx->radContext, &actx->radConn, configStanza) != 0) {
 438         err = rs_err_conn_pop(actx->radConn);
 439         return gssEapRadiusMapError(minor, err);
 440     }
 441
 442     if (actx->radServer != NULL) {
 443         if (rs_conn_select_peer(actx->radConn, actx->radServer) != 0) {
 444             err = rs_err_conn_pop(actx->radConn);
 445             return gssEapRadiusMapError(minor, err);
 446         }
 447     }
 448
 449     *minor = 0;
 450     return GSS_S_COMPLETE;
 451 }
 452
 453 /*
 454  * Process a EAP response from the initiator.
 455  */
 456 static OM_uint32
 457 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 458                            gss_cred_id_t cred,
 459                            gss_ctx_id_t ctx,
 460                            gss_name_t target GSSEAP_UNUSED,
 461                            gss_OID mech GSSEAP_UNUSED,
 462                            OM_uint32 reqFlags GSSEAP_UNUSED,
 463                            OM_uint32 timeReq GSSEAP_UNUSED,
 464                            gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 465                            gss_buffer_t inputToken,
 466                            gss_buffer_t outputToken,
 467                            OM_uint32 *smFlags)
 468 {
 469     OM_uint32 major, tmpMinor;
 470     struct rs_connection *rconn;
 471     struct rs_request *request = NULL;
 472     struct rs_packet *req = NULL, *resp = NULL;
 473     int isAccessChallenge;
 474
 475     if (ctx->acceptorCtx.radContext == NULL) {
 476         /* May be NULL from an imported partial context */
 477         major = createRadiusHandle(minor, cred, ctx);
 478         if (GSS_ERROR(major))
 479             goto cleanup;
 480     }
 481
 482     if (isIdentityResponseP(inputToken)) {
 483         major = importInitiatorIdentity(minor, ctx, inputToken);
 484         if (GSS_ERROR(major))
 485             return major;
 486     }
 487
 488     rconn = ctx->acceptorCtx.radConn;
 489
 490     if (rs_packet_create_authn_request(rconn, &req, NULL, NULL) != 0) {
 491         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 492         goto cleanup;
 493     }
 494
 495     major = setInitiatorIdentity(minor, ctx, req);
 496     if (GSS_ERROR(major))
 497         goto cleanup;
 498
 499     major = setAcceptorIdentity(minor, ctx, req);
 500     if (GSS_ERROR(major))
 501         goto cleanup;
 502
 503     major = gssEapRadiusAddAvp(minor, req,
 504                                PW_EAP_MESSAGE, 0, inputToken);
 505     if (GSS_ERROR(major))
 506         goto cleanup;
 507
 508     if (ctx->acceptorCtx.state.length != 0) {
 509         major = gssEapRadiusAddAvp(minor, req, PW_STATE, 0,
 510                                    &ctx->acceptorCtx.state);
 511         if (GSS_ERROR(major))
 512             goto cleanup;
 513
 514         gss_release_buffer(&tmpMinor, &ctx->acceptorCtx.state);
 515     }
 516
 517     if (rs_request_create(rconn, &request) != 0) {
 518         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 519         goto cleanup;
 520     }
 521
 522     rs_request_add_reqpkt(request, req);
 523     req = NULL;
 524
 525     if (rs_request_send(request, &resp) != 0) {
 526         major = gssEapRadiusMapError(minor, rs_err_conn_pop(rconn));
 527         goto cleanup;
 528     }
 529
 530     GSSEAP_ASSERT(resp != NULL);
 531
 532     isAccessChallenge = 0;
 533
 534     switch (rs_packet_code(resp)) {
 535     case PW_ACCESS_CHALLENGE:
 536         isAccessChallenge = 1;
 537         break;
 538     case PW_ACCESS_ACCEPT:
 539         break;
 540     case PW_ACCESS_REJECT:
 541         *minor = GSSEAP_RADIUS_AUTH_FAILURE;
 542         major = GSS_S_DEFECTIVE_CREDENTIAL;
 543         goto cleanup;
 544         break;
 545     default:
 546         *minor = GSSEAP_UNKNOWN_RADIUS_CODE;
 547         major = GSS_S_FAILURE;
 548         goto cleanup;
 549         break;
 550     }
 551
 552     major = gssEapRadiusGetAvp(minor, resp, PW_EAP_MESSAGE, 0,
 553                                outputToken, TRUE);
 554     if (major == GSS_S_UNAVAILABLE && isAccessChallenge) {
 555         *minor = GSSEAP_MISSING_EAP_REQUEST;
 556         major = GSS_S_DEFECTIVE_TOKEN;
 557         goto cleanup;
 558     } else if (GSS_ERROR(major))
 559         goto cleanup;
 560
 561     if (isAccessChallenge) {
 562         major = gssEapRadiusGetAvp(minor, resp, PW_STATE, 0,
 563                                    &ctx->acceptorCtx.state, TRUE);
 564         if (GSS_ERROR(major) && *minor != GSSEAP_NO_SUCH_ATTR)
 565             goto cleanup;
 566     } else {
 567         rs_avp **vps;
 568
 569         rs_packet_avps(resp, &vps);
 570
 571         ctx->acceptorCtx.vps = *vps;
 572         *vps = NULL;
 573
 574         major = acceptReadyEap(minor, ctx, cred);
 575         if (GSS_ERROR(major))
 576             goto cleanup;
 577
 578         GSSEAP_SM_TRANSITION_NEXT(ctx);
 579     }
 580
 581     major = GSS_S_CONTINUE_NEEDED;
 582     *minor = 0;
 583     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 584
 585 cleanup:
 586     if (request != NULL)
 587         rs_request_destroy(request);
 588     if (req != NULL)
 589         rs_packet_destroy(req);
 590     if (resp != NULL)
 591         rs_packet_destroy(resp);
 592     if (GSSEAP_SM_STATE(ctx) == GSSEAP_STATE_INITIATOR_EXTS) {
 593         GSSEAP_ASSERT(major == GSS_S_CONTINUE_NEEDED);
 594
 595         rs_conn_destroy(ctx->acceptorCtx.radConn);
 596         ctx->acceptorCtx.radConn = NULL;
 597     }
 598
 599     return major;
 600 }
 601
 602 static OM_uint32
 603 eapGssSmAcceptGssFlags(OM_uint32 *minor,
 604                        gss_cred_id_t cred GSSEAP_UNUSED,
 605                        gss_ctx_id_t ctx,
 606                        gss_name_t target GSSEAP_UNUSED,
 607                        gss_OID mech GSSEAP_UNUSED,
 608                        OM_uint32 reqFlags GSSEAP_UNUSED,
 609                        OM_uint32 timeReq GSSEAP_UNUSED,
 610                        gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 611                        gss_buffer_t inputToken,
 612                        gss_buffer_t outputToken GSSEAP_UNUSED,
 613                        OM_uint32 *smFlags GSSEAP_UNUSED)
 614 {
 615     unsigned char *p;
 616     OM_uint32 initiatorGssFlags;
 617
 618     GSSEAP_ASSERT((ctx->flags & CTX_FLAG_KRB_REAUTH) == 0);
 619
 620     if (inputToken->length < 4) {
 621         *minor = GSSEAP_TOK_TRUNC;
 622         return GSS_S_DEFECTIVE_TOKEN;
 623     }
 624
 625     /* allow flags to grow for future expansion */
 626     p = (unsigned char *)inputToken->value + inputToken->length - 4;
 627
 628     initiatorGssFlags = load_uint32_be(p);
 629     initiatorGssFlags &= GSSEAP_WIRE_FLAGS_MASK;
 630
 631     ctx->gssFlags |= initiatorGssFlags;
 632
 633     return GSS_S_CONTINUE_NEEDED;
 634 }
 635
 636 static OM_uint32
 637 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 638                                  gss_cred_id_t cred GSSEAP_UNUSED,
 639                                  gss_ctx_id_t ctx,
 640                                  gss_name_t target GSSEAP_UNUSED,
 641                                  gss_OID mech GSSEAP_UNUSED,
 642                                  OM_uint32 reqFlags GSSEAP_UNUSED,
 643                                  OM_uint32 timeReq GSSEAP_UNUSED,
 644                                  gss_channel_bindings_t chanBindings,
 645                                  gss_buffer_t inputToken,
 646                                  gss_buffer_t outputToken GSSEAP_UNUSED,
 647                                  OM_uint32 *smFlags GSSEAP_UNUSED)
 648 {
 649     krb5_error_code code;
 650     krb5_context krbContext;
 651     krb5_data data;
 652     krb5_checksum cksum;
 653     krb5_boolean valid = FALSE;
 654
 655     if (chanBindings == GSS_C_NO_CHANNEL_BINDINGS ||
 656         chanBindings->application_data.length == 0)
 657         return GSS_S_CONTINUE_NEEDED;
 658
 659     GSSEAP_KRB_INIT(&krbContext);
 660
 661     KRB_DATA_INIT(&data);
 662
 663     gssBufferToKrbData(&chanBindings->application_data, &data);
 664
 665     KRB_CHECKSUM_INIT(&cksum, ctx->checksumType, inputToken);
 666
 667     code = krb5_c_verify_checksum(krbContext, &ctx->rfc3961Key,
 668                                   KEY_USAGE_GSSEAP_CHBIND_MIC,
 669                                   &data, &cksum, &valid);
 670     if (code != 0) {
 671         *minor = code;
 672         return GSS_S_FAILURE;
 673     }
 674
 675     if (valid == FALSE) {
 676         *minor = GSSEAP_BINDINGS_MISMATCH;
 677         return GSS_S_BAD_BINDINGS;
 678     }
 679
 680     ctx->flags |= CTX_FLAG_CHANNEL_BINDINGS_VERIFIED;
 681
 682     *minor = 0;
 683     return GSS_S_CONTINUE_NEEDED;
 684 }
 685
 686 static OM_uint32
 687 eapGssSmAcceptInitiatorMIC(OM_uint32 *minor,
 688                            gss_cred_id_t cred GSSEAP_UNUSED,
 689                            gss_ctx_id_t ctx,
 690                            gss_name_t target GSSEAP_UNUSED,
 691                            gss_OID mech GSSEAP_UNUSED,
 692                            OM_uint32 reqFlags GSSEAP_UNUSED,
 693                            OM_uint32 timeReq GSSEAP_UNUSED,
 694                            gss_channel_bindings_t chanBindings,
 695                            gss_buffer_t inputToken,
 696                            gss_buffer_t outputToken GSSEAP_UNUSED,
 697                            OM_uint32 *smFlags GSSEAP_UNUSED)
 698 {
 699     OM_uint32 major;
 700
 701     /*
 702      * The channel binding token is optional, however if the caller indicated
 703      * bindings we must raise an error if it was absent.
 704      *
 705      * In the future, we might use a context option to allow the caller to
 706      * indicate that missing bindings are acceptable.
 707      */
 708     if (chanBindings != NULL &&
 709         chanBindings->application_data.length != 0 &&
 710         (ctx->flags & CTX_FLAG_CHANNEL_BINDINGS_VERIFIED) == 0) {
 711         *minor = GSSEAP_MISSING_BINDINGS;
 712         return GSS_S_BAD_BINDINGS;
 713     }
 714
 715     major = gssEapVerifyTokenMIC(minor, ctx, inputToken);
 716     if (GSS_ERROR(major))
 717         return major;
 718
 719     GSSEAP_SM_TRANSITION_NEXT(ctx);
 720
 721     *minor = 0;
 722     return GSS_S_CONTINUE_NEEDED;
 723 }
 724
 725 #ifdef GSSEAP_ENABLE_REAUTH
 726 static OM_uint32
 727 eapGssSmAcceptReauthCreds(OM_uint32 *minor,
 728                           gss_cred_id_t cred,
 729                           gss_ctx_id_t ctx,
 730                           gss_name_t target GSSEAP_UNUSED,
 731                           gss_OID mech GSSEAP_UNUSED,
 732                           OM_uint32 reqFlags GSSEAP_UNUSED,
 733                           OM_uint32 timeReq GSSEAP_UNUSED,
 734                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 735                           gss_buffer_t inputToken GSSEAP_UNUSED,
 736                           gss_buffer_t outputToken,
 737                           OM_uint32 *smFlags GSSEAP_UNUSED)
 738 {
 739     OM_uint32 major;
 740
 741     /*
 742      * If we're built with fast reauthentication enabled, then
 743      * fabricate a ticket from the initiator to ourselves.
 744      */
 745     major = gssEapMakeReauthCreds(minor, ctx, cred, outputToken);
 746     if (major == GSS_S_UNAVAILABLE)
 747         major = GSS_S_COMPLETE;
 748     if (major == GSS_S_COMPLETE)
 749         major = GSS_S_CONTINUE_NEEDED;
 750
 751     return major;
 752 }
 753 #endif
 754
 755 static OM_uint32
 756 eapGssSmAcceptAcceptorMIC(OM_uint32 *minor,
 757                           gss_cred_id_t cred GSSEAP_UNUSED,
 758                           gss_ctx_id_t ctx,
 759                           gss_name_t target GSSEAP_UNUSED,
 760                           gss_OID mech GSSEAP_UNUSED,
 761                           OM_uint32 reqFlags GSSEAP_UNUSED,
 762                           OM_uint32 timeReq GSSEAP_UNUSED,
 763                           gss_channel_bindings_t chanBindings GSSEAP_UNUSED,
 764                           gss_buffer_t inputToken GSSEAP_UNUSED,
 765                           gss_buffer_t outputToken,
 766                           OM_uint32 *smFlags)
 767 {
 768     OM_uint32 major;
 769
 770     major = gssEapMakeTokenMIC(minor, ctx, outputToken);
 771     if (GSS_ERROR(major))
 772         return major;
 773
 774     GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
 775
 776     *minor = 0;
 777     *smFlags |= SM_FLAG_OUTPUT_TOKEN_CRITICAL;
 778
 779     return GSS_S_COMPLETE;
 780 }
 781
 782 static struct gss_eap_sm eapGssAcceptorSm[] = {
 783     {
 784         ITOK_TYPE_ACCEPTOR_NAME_REQ,
 785         ITOK_TYPE_ACCEPTOR_NAME_RESP,
 786         GSSEAP_STATE_INITIAL,
 787         0,
 788         eapGssSmAcceptAcceptorName
 789     },
 790 #ifdef GSSEAP_DEBUG
 791     {
 792         ITOK_TYPE_VENDOR_INFO,
 793         ITOK_TYPE_NONE,
 794         GSSEAP_STATE_INITIAL,
 795         0,
 796         eapGssSmAcceptVendorInfo,
 797     },
 798 #endif
 799 #ifdef GSSEAP_ENABLE_REAUTH
 800     {
 801         ITOK_TYPE_REAUTH_REQ,
 802         ITOK_TYPE_REAUTH_RESP,
 803         GSSEAP_STATE_INITIAL,
 804         0,
 805         eapGssSmAcceptGssReauth,
 806     },
 807 #endif
 808     {
 809         ITOK_TYPE_NONE,
 810         ITOK_TYPE_EAP_REQ,
 811         GSSEAP_STATE_INITIAL,
 812         SM_ITOK_FLAG_REQUIRED,
 813         eapGssSmAcceptIdentity,
 814     },
 815     {
 816         ITOK_TYPE_EAP_RESP,
 817         ITOK_TYPE_EAP_REQ,
 818         GSSEAP_STATE_AUTHENTICATE,
 819         SM_ITOK_FLAG_REQUIRED,
 820         eapGssSmAcceptAuthenticate
 821     },
 822     {
 823         ITOK_TYPE_GSS_FLAGS,
 824         ITOK_TYPE_NONE,
 825         GSSEAP_STATE_INITIATOR_EXTS,
 826         0,
 827         eapGssSmAcceptGssFlags
 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_NAME_RESP,
 855         GSSEAP_STATE_ACCEPTOR_EXTS,
 856         0,
 857         eapGssSmAcceptAcceptorName
 858     },
 859     {
 860         ITOK_TYPE_NONE,
 861         ITOK_TYPE_ACCEPTOR_MIC,
 862         GSSEAP_STATE_ACCEPTOR_EXTS,
 863         0,
 864         eapGssSmAcceptAcceptorMIC
 865     },
 866 };
 867
 868 OM_uint32
 869 gssEapAcceptSecContext(OM_uint32 *minor,
 870                        gss_ctx_id_t ctx,
 871                        gss_cred_id_t cred,
 872                        gss_buffer_t input_token,
 873                        gss_channel_bindings_t input_chan_bindings,
 874                        gss_name_t *src_name,
 875                        gss_OID *mech_type,
 876                        gss_buffer_t output_token,
 877                        OM_uint32 *ret_flags,
 878                        OM_uint32 *time_rec,
 879                        gss_cred_id_t *delegated_cred_handle)
 880 {
 881     OM_uint32 major, tmpMinor;
 882
 883     if (cred == GSS_C_NO_CREDENTIAL) {
 884         if (ctx->cred == GSS_C_NO_CREDENTIAL) {
 885             major = gssEapAcquireCred(minor,
 886                                       GSS_C_NO_NAME,
 887                                       GSS_C_INDEFINITE,
 888                                       GSS_C_NO_OID_SET,
 889                                       GSS_C_ACCEPT,
 890                                       &ctx->cred,
 891                                       NULL,
 892                                       NULL);
 893             if (GSS_ERROR(major))
 894                 goto cleanup;
 895         }
 896
 897         cred = ctx->cred;
 898     }
 899
 900     /*
 901      * Previously we acquired the credential mutex here, but it should not be
 902      * necessary as the acceptor does not access any mutable elements of the
 903      * credential handle.
 904      */
 905
 906     /*
 907      * Calling gssEapInquireCred() forces the default acceptor credential name
 908      * to be resolved.
 909      */
 910     major = gssEapInquireCred(minor, cred, &ctx->acceptorName, NULL, NULL, NULL);
 911     if (GSS_ERROR(major))
 912         goto cleanup;
 913
 914     major = gssEapSmStep(minor,
 915                          cred,
 916                          ctx,
 917                          GSS_C_NO_NAME,
 918                          GSS_C_NO_OID,
 919                          0,
 920                          GSS_C_INDEFINITE,
 921                          input_chan_bindings,
 922                          input_token,
 923                          output_token,
 924                          eapGssAcceptorSm,
 925                          sizeof(eapGssAcceptorSm) / sizeof(eapGssAcceptorSm[0]));
 926     if (GSS_ERROR(major))
 927         goto cleanup;
 928
 929     if (mech_type != NULL) {
 930         OM_uint32 tmpMajor;
 931
 932         tmpMajor = gssEapCanonicalizeOid(&tmpMinor, ctx->mechanismUsed, 0, mech_type);
 933         if (GSS_ERROR(tmpMajor)) {
 934             major = tmpMajor;
 935             *minor = tmpMinor;
 936             goto cleanup;
 937         }
 938     }
 939     if (ret_flags != NULL)
 940         *ret_flags = ctx->gssFlags;
 941     if (delegated_cred_handle != NULL)
 942         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 943
 944     if (major == GSS_S_COMPLETE) {
 945         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 946             major = gssEapDuplicateName(&tmpMinor, ctx->initiatorName, src_name);
 947             if (GSS_ERROR(major))
 948                 goto cleanup;
 949         }
 950         if (time_rec != NULL) {
 951             major = gssEapContextTime(&tmpMinor, ctx, time_rec);
 952             if (GSS_ERROR(major))
 953                 goto cleanup;
 954         }
 955     }
 956
 957     GSSEAP_ASSERT(CTX_IS_ESTABLISHED(ctx) || major == GSS_S_CONTINUE_NEEDED);
 958
 959 cleanup:
 960     return major;
 961 }
 962
 963 #ifdef GSSEAP_ENABLE_REAUTH
 964 static OM_uint32
 965 acceptReadyKrb(OM_uint32 *minor,
 966                gss_ctx_id_t ctx,
 967                gss_cred_id_t cred,
 968                const gss_name_t initiator,
 969                const gss_OID mech,
 970                OM_uint32 timeRec)
 971 {
 972     OM_uint32 major;
 973
 974     major = gssEapGlueToMechName(minor, ctx, initiator, &ctx->initiatorName);
 975     if (GSS_ERROR(major))
 976         return major;
 977
 978     major = gssEapReauthComplete(minor, ctx, cred, mech, timeRec);
 979     if (GSS_ERROR(major))
 980         return major;
 981
 982     *minor = 0;
 983     return GSS_S_COMPLETE;
 984 }
 985
 986 static OM_uint32
 987 eapGssSmAcceptGssReauth(OM_uint32 *minor,
 988                         gss_cred_id_t cred,
 989                         gss_ctx_id_t ctx,
 990                         gss_name_t target GSSEAP_UNUSED,
 991                         gss_OID mech,
 992                         OM_uint32 reqFlags GSSEAP_UNUSED,
 993                         OM_uint32 timeReq GSSEAP_UNUSED,
 994                         gss_channel_bindings_t chanBindings,
 995                         gss_buffer_t inputToken,
 996                         gss_buffer_t outputToken,
 997                         OM_uint32 *smFlags)
 998 {
 999     OM_uint32 major, tmpMinor;
1000     gss_name_t krbInitiator = GSS_C_NO_NAME;
1001     OM_uint32 gssFlags, timeRec = GSS_C_INDEFINITE;
1002
1003     /*
1004      * If we're built with fast reauthentication support, it's valid
1005      * for an initiator to send a GSS reauthentication token as its
1006      * initial context token, causing us to short-circuit the state
1007      * machine and process Kerberos GSS messages instead.
1008      */
1009
1010     ctx->flags |= CTX_FLAG_KRB_REAUTH;
1011
1012     major = gssAcceptSecContext(minor,
1013                                 &ctx->reauthCtx,
1014                                 cred->reauthCred,
1015                                 inputToken,
1016                                 chanBindings,
1017                                 &krbInitiator,
1018                                 &mech,
1019                                 outputToken,
1020                                 &gssFlags,
1021                                 &timeRec,
1022                                 NULL);
1023     if (major == GSS_S_COMPLETE) {
1024         major = acceptReadyKrb(minor, ctx, cred,
1025                                krbInitiator, mech, timeRec);
1026         if (major == GSS_S_COMPLETE) {
1027             GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_ESTABLISHED);
1028         }
1029         ctx->gssFlags = gssFlags;
1030     } else if (GSS_ERROR(major) &&
1031         (*smFlags & SM_FLAG_INPUT_TOKEN_CRITICAL) == 0) {
1032         /* pretend reauthentication attempt never happened */
1033         gssDeleteSecContext(&tmpMinor, &ctx->reauthCtx, GSS_C_NO_BUFFER);
1034         ctx->flags &= ~(CTX_FLAG_KRB_REAUTH);
1035         GSSEAP_SM_TRANSITION(ctx, GSSEAP_STATE_INITIAL);
1036         major = GSS_S_CONTINUE_NEEDED;
1037     }
1038
1039     gssReleaseName(&tmpMinor, &krbInitiator);
1040
1041     return major;
1042 }
1043 #endif /* GSSEAP_ENABLE_REAUTH */
1044
1045 OM_uint32 GSSAPI_CALLCONV
1046 gss_accept_sec_context(OM_uint32 *minor,
1047                        gss_ctx_id_t *context_handle,
1048                        gss_cred_id_t cred,
1049                        gss_buffer_t input_token,
1050                        gss_channel_bindings_t input_chan_bindings,
1051                        gss_name_t *src_name,
1052                        gss_OID *mech_type,
1053                        gss_buffer_t output_token,
1054                        OM_uint32 *ret_flags,
1055                        OM_uint32 *time_rec,
1056                        gss_cred_id_t *delegated_cred_handle)
1057 {
1058     OM_uint32 major, tmpMinor;
1059     gss_ctx_id_t ctx = *context_handle;
1060
1061     *minor = 0;
1062
1063     output_token->length = 0;
1064     output_token->value = NULL;
1065
1066     if (src_name != NULL)
1067         *src_name = GSS_C_NO_NAME;
1068
1069     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
1070         *minor = GSSEAP_TOK_TRUNC;
1071         return GSS_S_DEFECTIVE_TOKEN;
1072     }
1073
1074     if (ctx == GSS_C_NO_CONTEXT) {
1075         major = gssEapAllocContext(minor, &ctx);
1076         if (GSS_ERROR(major))
1077             return major;
1078
1079         *context_handle = ctx;
1080     }
1081
1082     GSSEAP_MUTEX_LOCK(&ctx->mutex);
1083
1084     major = gssEapAcceptSecContext(minor,
1085                                    ctx,
1086                                    cred,
1087                                    input_token,
1088                                    input_chan_bindings,
1089                                    src_name,
1090                                    mech_type,
1091                                    output_token,
1092                                    ret_flags,
1093                                    time_rec,
1094                                    delegated_cred_handle);
1095
1096     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
1097
1098     if (GSS_ERROR(major))
1099         gssEapReleaseContext(&tmpMinor, context_handle);
1100
1101     return major;
1102 }