www.project-moonshot.org Git - mech_eap.orig/blob - accept_sec_context.c

   1 /*
   2  * Copyright (c) 2010, JANET(UK)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. Neither the name of JANET(UK) nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "gssapiP_eap.h"
  34
  35 //#define BUILTIN_EAP
  36
  37 #ifdef BUILTIN_EAP
  38 #define EAP_KEY_AVAILABLE(ctx)  ((ctx)->acceptorCtx.eapPolInterface->eapKeyAvailable)
  39 #define EAP_KEY_DATA(ctx)       ((ctx)->acceptorCtx.eapPolInterface->eapKeyData)
  40 #define EAP_KEY_LENGTH(ctx)     ((ctx)->acceptorCtx.eapPolInterface->eapKeyDataLen)
  41 #else
  42 #define EAP_KEY_AVAILABLE(ctx)  0
  43 #define EAP_KEY_DATA(ctx)       NULL
  44 #define EAP_KEY_LENGTH(ctx)     0
  45 #endif /* BUILTIN_EAP */
  46
  47 /*
  48  * Mark a context as ready for cryptographic operations
  49  */
  50 static OM_uint32
  51 acceptReady(OM_uint32 *minor, gss_ctx_id_t ctx)
  52 {
  53     OM_uint32 major;
  54
  55     /* Cache encryption type derived from selected mechanism OID */
  56     major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &ctx->encryptionType);
  57     if (GSS_ERROR(major))
  58         return major;
  59
  60     if (ctx->encryptionType != ENCTYPE_NULL &&
  61         EAP_KEY_AVAILABLE(ctx)) {
  62         major = gssEapDeriveRfc3961Key(minor,
  63                                        EAP_KEY_DATA(ctx),
  64                                        EAP_KEY_LENGTH(ctx),
  65                                        ctx->encryptionType,
  66                                        &ctx->rfc3961Key);
  67         if (GSS_ERROR(major))
  68             return major;
  69
  70         major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
  71                                            &ctx->checksumType);
  72         if (GSS_ERROR(major))
  73             return major;
  74     } else {
  75         /*
  76          * draft-howlett-eap-gss says that integrity/confidentialty should
  77          * always be advertised as available, but if we have no keying
  78          * material it seems confusing to the caller to advertise this.
  79          */
  80         ctx->gssFlags &= ~(GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
  81     }
  82
  83     major = sequenceInit(minor,
  84                          &ctx->seqState, ctx->recvSeq,
  85                          ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
  86                          ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
  87                          TRUE);
  88     if (GSS_ERROR(major))
  89         return major;
  90
  91     return GSS_S_COMPLETE;
  92 }
  93
  94 #ifdef BUILTIN_EAP
  95 #define EAP_MAX_METHODS 8
  96
  97 #define EAP_TTLS_AUTH_PAP 1
  98 #define EAP_TTLS_AUTH_CHAP 2
  99 #define EAP_TTLS_AUTH_MSCHAP 4
 100 #define EAP_TTLS_AUTH_MSCHAPV2 8
 101
 102 struct eap_user {
 103         struct {
 104                 int vendor;
 105                 u32 method;
 106         } methods[EAP_MAX_METHODS];
 107         u8 *password;
 108         size_t password_len;
 109         int password_hash; /* whether password is hashed with
 110                             * nt_password_hash() */
 111         int phase2;
 112         int force_version;
 113         int ttls_auth; /* bitfield of
 114                         * EAP_TTLS_AUTH_{PAP,CHAP,MSCHAP,MSCHAPV2} */
 115 };
 116
 117 struct eap_eapol_interface {
 118         /* Lower layer to full authenticator variables */
 119         Boolean eapResp; /* shared with EAPOL Backend Authentication */
 120         struct wpabuf *eapRespData;
 121         Boolean portEnabled;
 122         int retransWhile;
 123         Boolean eapRestart; /* shared with EAPOL Authenticator PAE */
 124         int eapSRTT;
 125         int eapRTTVAR;
 126
 127         /* Full authenticator to lower layer variables */
 128         Boolean eapReq; /* shared with EAPOL Backend Authentication */
 129         Boolean eapNoReq; /* shared with EAPOL Backend Authentication */
 130         Boolean eapSuccess;
 131         Boolean eapFail;
 132         Boolean eapTimeout;
 133         struct wpabuf *eapReqData;
 134         u8 *eapKeyData;
 135         size_t eapKeyDataLen;
 136         Boolean eapKeyAvailable; /* called keyAvailable in IEEE 802.1X-2004 */
 137
 138         /* AAA interface to full authenticator variables */
 139         Boolean aaaEapReq;
 140         Boolean aaaEapNoReq;
 141         Boolean aaaSuccess;
 142         Boolean aaaFail;
 143         struct wpabuf *aaaEapReqData;
 144         u8 *aaaEapKeyData;
 145         size_t aaaEapKeyDataLen;
 146         Boolean aaaEapKeyAvailable;
 147         int aaaMethodTimeout;
 148
 149         /* Full authenticator to AAA interface variables */
 150         Boolean aaaEapResp;
 151         struct wpabuf *aaaEapRespData;
 152         /* aaaIdentity -> eap_get_identity() */
 153         Boolean aaaTimeout;
 154 };
 155
 156 #define eapol_callbacks     SERVER_eapol_callbacks
 157
 158 struct eapol_callbacks {
 159         int (*get_eap_user)(void *ctx, const u8 *identity, size_t identity_len,
 160                             int phase2, struct eap_user *user);
 161         const char * (*get_eap_req_id_text)(void *ctx, size_t *len);
 162 };
 163
 164 #define eap_config          SERVER_eap_config
 165
 166 struct eap_config {
 167         void *ssl_ctx;
 168         void *msg_ctx;
 169         void *eap_sim_db_priv;
 170         Boolean backend_auth;
 171         int eap_server;
 172         u8 *pac_opaque_encr_key;
 173         u8 *eap_fast_a_id;
 174         size_t eap_fast_a_id_len;
 175         char *eap_fast_a_id_info;
 176         int eap_fast_prov;
 177         int pac_key_lifetime;
 178         int pac_key_refresh_time;
 179         int eap_sim_aka_result_ind;
 180         int tnc;
 181         struct wps_context *wps;
 182         const struct wpabuf *assoc_wps_ie;
 183         const u8 *peer_addr;
 184         int fragment_size;
 185 };
 186
 187 struct eap_sm * eap_server_sm_init(void *eapol_ctx,
 188                                    struct eapol_callbacks *eapol_cb,
 189                                    struct eap_config *eap_conf);
 190 void eap_server_sm_deinit(struct eap_sm *sm);
 191 int eap_server_sm_step(struct eap_sm *sm);
 192 void eap_sm_notify_cached(struct eap_sm *sm);
 193 void eap_sm_pending_cb(struct eap_sm *sm);
 194 int eap_sm_method_pending(struct eap_sm *sm);
 195 const u8 * eap_get_identity(struct eap_sm *sm, size_t *len);
 196 struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm);
 197
 198 #include <eap_server/eap_i.h>
 199
 200 static OM_uint32
 201 initTls(OM_uint32 *minor,
 202         gss_ctx_id_t ctx)
 203 {
 204     struct tls_config tconf;
 205     struct tls_connection_params tparams;
 206
 207     memset(&tconf, 0, sizeof(tconf));
 208     ctx->acceptorCtx.tlsContext = tls_init(&tconf);
 209     if (ctx->acceptorCtx.tlsContext == NULL)
 210         return GSS_S_FAILURE;
 211
 212     memset(&tparams, 0, sizeof(tparams));
 213     tparams.ca_cert = "ca.pem";
 214     tparams.client_cert = "server.pem";
 215     tparams.private_key = "server-key.pem";
 216
 217     if (tls_global_set_params(ctx->acceptorCtx.tlsContext, &tparams)) {
 218         return GSS_S_FAILURE;
 219     }
 220
 221     if (tls_global_set_verify(ctx->acceptorCtx.tlsContext, 0)) {
 222         return GSS_S_FAILURE;
 223     }
 224
 225     return GSS_S_COMPLETE;
 226 }
 227
 228 static int
 229 serverGetEapUser(void *ctx,
 230                  const unsigned char *identity,
 231                  size_t identityLength,
 232                  int phase2,
 233                  struct eap_user *user)
 234 {
 235     gss_ctx_id_t gssCtx = (gss_ctx_id_t)ctx;
 236     OM_uint32 major, minor;
 237     gss_buffer_desc buf;
 238
 239     memset(user, 0, sizeof(*user));
 240
 241     buf.length = identityLength;
 242     buf.value = (void *)identity;
 243
 244     if (phase2 == 0) {
 245         user->methods[0].vendor = EAP_VENDOR_IETF;
 246         user->methods[0].method = EAP_TYPE_PEAP;
 247         return 0;
 248     }
 249
 250     major = gssEapImportName(&minor, &buf, GSS_C_NT_USER_NAME,
 251                              &gssCtx->initiatorName);
 252     if (GSS_ERROR(major))
 253         return -1;
 254
 255     /*
 256      * OK, obviously there is no real security here, this is simply
 257      * for testing the token exchange; this code will be completely
 258      * replaced with libradsec once that library is available.
 259      */
 260     user->methods[0].vendor = EAP_VENDOR_IETF;
 261     user->methods[0].method = EAP_TYPE_MSCHAPV2;
 262     user->password = (unsigned char *)strdup(" ");
 263     user->password_len = 1;
 264
 265     return 0;
 266 }
 267
 268 static const char *
 269 serverGetEapReqIdText(void *ctx,
 270                       size_t *len)
 271 {
 272     *len = 0;
 273     return NULL;
 274 }
 275
 276 static OM_uint32
 277 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 278                            gss_ctx_id_t ctx,
 279                            gss_cred_id_t cred,
 280                            gss_buffer_t inputToken,
 281                            gss_channel_bindings_t chanBindings,
 282                            gss_buffer_t outputToken)
 283 {
 284     OM_uint32 major;
 285     OM_uint32 tmpMinor, tmpMajor;
 286     int code;
 287     struct wpabuf respData;
 288     static struct eapol_callbacks cb = { serverGetEapUser, serverGetEapReqIdText };
 289     if (ctx->acceptorCtx.eap == NULL) {
 290         struct eap_config eapConfig;
 291
 292         major = initTls(minor, ctx);
 293         if (GSS_ERROR(major))
 294             goto cleanup;
 295
 296         memset(&eapConfig, 0, sizeof(eapConfig));
 297         eapConfig.eap_server = 1;
 298         eapConfig.ssl_ctx = ctx->acceptorCtx.tlsContext;
 299
 300         ctx->acceptorCtx.eap = eap_server_sm_init(ctx, &cb, &eapConfig);
 301         if (ctx->acceptorCtx.eap == NULL) {
 302             major = GSS_S_FAILURE;
 303             goto cleanup;
 304         }
 305
 306         ctx->acceptorCtx.eapPolInterface = eap_get_interface(ctx->acceptorCtx.eap);
 307         ctx->acceptorCtx.eapPolInterface->portEnabled = TRUE;
 308         ctx->acceptorCtx.eapPolInterface->eapRestart = TRUE;
 309     }
 310
 311     if (ctx->acceptorName == GSS_C_NO_NAME &&
 312         cred != GSS_C_NO_CREDENTIAL &&
 313         cred->name != GSS_C_NO_NAME) {
 314         major = gss_duplicate_name(minor, cred->name, &ctx->acceptorName);
 315         if (GSS_ERROR(major))
 316             goto cleanup;
 317     }
 318
 319     wpabuf_set(&respData, inputToken->value, inputToken->length);
 320     ctx->acceptorCtx.eapPolInterface->eapRespData = &respData;
 321     ctx->acceptorCtx.eapPolInterface->eapResp = TRUE;
 322
 323     code = eap_server_sm_step(ctx->acceptorCtx.eap);
 324
 325     if (ctx->acceptorCtx.eapPolInterface->eapReq) {
 326         ctx->acceptorCtx.eapPolInterface->eapReq = 0;
 327         major = GSS_S_CONTINUE_NEEDED;
 328     }
 329
 330     if (ctx->acceptorCtx.eapPolInterface->eapSuccess) {
 331         ctx->acceptorCtx.eapPolInterface->eapSuccess = 0;
 332         major = acceptReady(minor, ctx);
 333         if (GSS_ERROR(major))
 334             goto cleanup;
 335
 336         ctx->state = EAP_STATE_GSS_CHANNEL_BINDINGS;
 337         major = GSS_S_CONTINUE_NEEDED;
 338     } else if (ctx->acceptorCtx.eapPolInterface->eapFail) {
 339         ctx->acceptorCtx.eapPolInterface->eapFail = 0;
 340         major = GSS_S_FAILURE;
 341     } else if (code == 0) {
 342         major = GSS_S_FAILURE;
 343     }
 344
 345     if (ctx->acceptorCtx.eapPolInterface->eapReqData != NULL) {
 346         gss_buffer_desc buf;
 347
 348         buf.length = wpabuf_len(ctx->acceptorCtx.eapPolInterface->eapReqData);
 349         buf.value = (void *)wpabuf_head(ctx->acceptorCtx.eapPolInterface->eapReqData);
 350
 351         tmpMajor = duplicateBuffer(&tmpMinor, &buf, outputToken);
 352         if (GSS_ERROR(tmpMajor)) {
 353             major = tmpMajor;
 354             *minor = tmpMinor;
 355             goto cleanup;
 356         }
 357     }
 358
 359 cleanup:
 360     ctx->acceptorCtx.eapPolInterface->eapRespData = NULL;
 361
 362     return major;
 363 }
 364 #else
 365 static OM_uint32
 366 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 367                            gss_ctx_id_t ctx,
 368                            gss_cred_id_t cred,
 369                            gss_buffer_t inputToken,
 370                            gss_channel_bindings_t chanBindings,
 371                            gss_buffer_t outputToken)
 372 {
 373     OM_uint32 major, tmpMinor;
 374
 375 cleanup:
 376     return major;
 377 }
 378 #endif /* BUILTIN_EAP */
 379
 380 static OM_uint32
 381 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 382                                  gss_ctx_id_t ctx,
 383                                  gss_cred_id_t cred,
 384                                  gss_buffer_t inputToken,
 385                                  gss_channel_bindings_t chanBindings,
 386                                  gss_buffer_t outputToken)
 387 {
 388     OM_uint32 major, tmpMinor;
 389     gss_iov_buffer_desc iov[2];
 390
 391     outputToken->length = 0;
 392     outputToken->value = NULL;
 393
 394     if (chanBindings == GSS_C_NO_CHANNEL_BINDINGS) {
 395         ctx->state = EAP_STATE_ESTABLISHED;
 396         return GSS_S_COMPLETE;
 397     }
 398
 399     if (inputToken->length < 14) {
 400         return GSS_S_DEFECTIVE_TOKEN;
 401     }
 402
 403     iov[0].type = GSS_IOV_BUFFER_TYPE_DATA;
 404     iov[0].buffer.length = 0;
 405     iov[0].buffer.value = NULL;
 406
 407     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS)
 408         iov[0].buffer = chanBindings->application_data;
 409
 410     iov[1].type = GSS_IOV_BUFFER_TYPE_HEADER;
 411     iov[1].buffer.length = 16;
 412     iov[1].buffer.value = (unsigned char *)inputToken->value - 2;
 413
 414     assert(load_uint16_be(iov[1].buffer.value) == TOK_TYPE_GSS_CB);
 415
 416     iov[2].type = GSS_IOV_BUFFER_TYPE_TRAILER;
 417     iov[2].buffer.length = inputToken->length - 14;
 418     iov[2].buffer.value = (unsigned char *)inputToken->value + 14;
 419
 420     major = gssEapUnwrapOrVerifyMIC(minor, ctx, NULL, NULL,
 421                                     iov, 3, TOK_TYPE_GSS_CB);
 422     if (major == GSS_S_COMPLETE) {
 423         ctx->state = EAP_STATE_ESTABLISHED;
 424     }
 425
 426 #if 0
 427     gss_release_buffer(&tmpMinor, &iov[0].buffer);
 428 #endif
 429
 430     return major;
 431 }
 432
 433 static OM_uint32
 434 eapGssSmAcceptEstablished(OM_uint32 *minor,
 435                           gss_ctx_id_t ctx,
 436                           gss_cred_id_t cred,
 437                           gss_buffer_t inputToken,
 438                           gss_channel_bindings_t chanBindings,
 439                           gss_buffer_t outputToken)
 440 {
 441     /* Called with already established context */
 442     *minor = EINVAL;
 443     return GSS_S_BAD_STATUS;
 444 }
 445
 446 static struct eap_gss_acceptor_sm {
 447     enum gss_eap_token_type inputTokenType;
 448     enum gss_eap_token_type outputTokenType;
 449     OM_uint32 (*processToken)(OM_uint32 *,
 450                               gss_ctx_id_t,
 451                               gss_cred_id_t,
 452                               gss_buffer_t,
 453                               gss_channel_bindings_t,
 454                               gss_buffer_t);
 455 } eapGssAcceptorSm[] = {
 456     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  eapGssSmAcceptAuthenticate       },
 457 #if 0
 458     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                             },
 459     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                             },
 460 #endif
 461     { TOK_TYPE_GSS_CB,      TOK_TYPE_NONE,     eapGssSmAcceptGssChannelBindings },
 462     { TOK_TYPE_NONE,        TOK_TYPE_NONE,     eapGssSmAcceptEstablished        },
 463 };
 464
 465 OM_uint32
 466 gss_accept_sec_context(OM_uint32 *minor,
 467                        gss_ctx_id_t *context_handle,
 468                        gss_cred_id_t cred,
 469                        gss_buffer_t input_token,
 470                        gss_channel_bindings_t input_chan_bindings,
 471                        gss_name_t *src_name,
 472                        gss_OID *mech_type,
 473                        gss_buffer_t output_token,
 474                        OM_uint32 *ret_flags,
 475                        OM_uint32 *time_rec,
 476                        gss_cred_id_t *delegated_cred_handle)
 477 {
 478     OM_uint32 major;
 479     OM_uint32 tmpMajor, tmpMinor;
 480     gss_ctx_id_t ctx = *context_handle;
 481     struct eap_gss_acceptor_sm *sm = NULL;
 482     gss_buffer_desc innerInputToken, innerOutputToken;
 483
 484     *minor = 0;
 485
 486     innerOutputToken.length = 0;
 487     innerOutputToken.value = NULL;
 488
 489     output_token->length = 0;
 490     output_token->value = NULL;
 491
 492     if (cred != GSS_C_NO_CREDENTIAL && !(cred->flags & CRED_FLAG_ACCEPT)) {
 493         return GSS_S_NO_CRED;
 494     }
 495
 496     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 497         return GSS_S_DEFECTIVE_TOKEN;
 498     }
 499
 500     if (ctx == GSS_C_NO_CONTEXT) {
 501         major = gssEapAllocContext(minor, &ctx);
 502         if (GSS_ERROR(major))
 503             return major;
 504
 505         *context_handle = ctx;
 506     }
 507
 508     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 509
 510     sm = &eapGssAcceptorSm[ctx->state];
 511
 512     major = gssEapVerifyToken(minor, ctx, input_token,
 513                               sm->inputTokenType, &innerInputToken);
 514     if (GSS_ERROR(major))
 515         goto cleanup;
 516
 517     /* If credentials were provided, check they're usable with this mech */
 518     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 519         major = GSS_S_BAD_MECH;
 520         goto cleanup;
 521     }
 522
 523     do {
 524         sm = &eapGssAcceptorSm[ctx->state];
 525
 526         major = (sm->processToken)(minor,
 527                                    ctx,
 528                                    cred,
 529                                    &innerInputToken,
 530                                    input_chan_bindings,
 531                                    &innerOutputToken);
 532         if (GSS_ERROR(major))
 533             goto cleanup;
 534     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.length == 0);
 535
 536     if (mech_type != NULL) {
 537         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 538             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 539     }
 540     if (innerOutputToken.length != 0) {
 541         tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
 542                                    sm->outputTokenType, output_token);
 543         if (GSS_ERROR(tmpMajor)) {
 544             major = tmpMajor;
 545             *minor = tmpMinor;
 546             goto cleanup;
 547         }
 548     }
 549     if (ret_flags != NULL)
 550         *ret_flags = ctx->gssFlags;
 551     if (delegated_cred_handle != NULL)
 552         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 553
 554     if (major == GSS_S_COMPLETE) {
 555         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 556             major = gss_duplicate_name(&tmpMinor, ctx->initiatorName, src_name);
 557             if (GSS_ERROR(major))
 558                 goto cleanup;
 559         }
 560         if (time_rec != NULL)
 561             gss_context_time(&tmpMinor, ctx, time_rec);
 562     }
 563
 564     assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 565
 566 cleanup:
 567     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 568
 569     if (GSS_ERROR(major))
 570         gssEapReleaseContext(&tmpMinor, context_handle);
 571
 572     gss_release_buffer(&tmpMinor, &innerOutputToken);
 573
 574     return major;
 575 }